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    2e unofficial reference manual (May 2024)
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    <para>
      This document is an unofficial reference manual for
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      , a document preparation system, version of May 2024.
    </para>
    <para>
      This manual was originally translated from
      <file>
        LATEX.HLP
      </file>
       v1.0a in the VMS Help Library. The pre-translation version was written by George
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      D. Greenwade of Sam Houston State University. The
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      2.09 version was written by Stephen Gilmore. The
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      2e version was adapted from this by Torsten Martinsen. Karl Berry made further updates and additions, and gratefully acknowledges using
      <cite>
        Hypertext Help with
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      </cite>
      , by Sheldon Green, and
      <citeDefault handler: &latex;
>
         Command Summary
      </cite>
       (for
Default handler: &latex;
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      2.09) by L.
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      Botway and C.
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      Biemesderfer (published by the
Default handler: &tex;
       Users Group as
      <citeDefault handler: &tex;
>
        niques
      </cite>
       number 10), as reference material. We also gratefully acknowledge additional material appearing in latex2e-reference by Martin Herbert Dietze. (From these references no text was directly copied.)
    </para>
    <para>
      Copyright 2007, 2008, 2009, 2010, 2011, 2012, 2013, 2014, 2015, 2016, 2017, 2018, 2019, 2020, 2021, 2022 Karl Berry.
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       Copyright 1988, 1994, 2007 Stephen Gilmore.
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       Copyright 1994, 1995, 1996 Torsten Martinsen.
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      Permission is granted to make and distribute verbatim copies of this manual provided the copyright notice and this permission notice are preserved on all copies.
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      Permission is granted to copy and distribute translations of this manual into another language, under the above conditions for modified versions.
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    TeX
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        *
      </menuleadingtext>
      <menutitle>
        LaTeX2e
      </menutitle>
      <menuseparator>
        :
      </menuseparator>
      <menunode>
        (latex2e)
      </menunode>
      <menuseparator>
        .
      </menuseparator>
      <menudescription>
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          Unofficial LaTeX reference manual.
        </pre>
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    <
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    p
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    This is an unofficial reference manual for LaTeX. See below for the
    <
    a href='#SEC_Overview'
    >
    Table of Contents
    <
    /a
    >
    . If you want a tutorial then please instead visit
    <
    a href=
    "
    https://www.learnlatex.org/
    "
    >
    <
    code
    >
    learnlatex.org
    <
    /code
    >
    <
    /a
    >
     or see
    <
    a href='https://ctan.org/topic/tut-latex'
    >
    this long list
    <
    /a
    >
    .
    <
    /p
    >
    <
    p
    >
    This manual has two versions. One has
    <
    a href=
    "
    https://latexref.xyz/
    "
    >
    separate web pages for each section or subsection
    <
    /a
    >
    . It's also available as a
    <
    a href=
    "
    https://latexref.xyz/dev/latex2e.html
    "
    >
    single web page
    <
    /a
    >
     and as a
    <
    a href=
    "
    https://latexref.xyz/dev/latex2e.pdf
    "
    >
    pdf
    <
    /a
    >
    . Translations to French and Spanish are available at @url{https://ctan.org/pkg/latex2e-help-texinfo}; they're maintained separately.
    <
    p
    >
     This document is not official. It has not been reviewed by the LaTeX maintainers. Our ultimate goal is to cover all (non-private) LaTeX commands. Your comments and contributions, including bug reports, are very welcome. See
    <
    a href='https://latexref.xyz/dev/'
    >
    our project page
    <
    /a
    >
     for more, including
    <
    a href='https://latexref.xyz/dev/#license'
    >
    license information
    <
    /a
    >
     and information on how you can
    <
    a href='https://latexref.xyz/dev/writing.html'
    >
    contribute to this manual
    <
    /a
    >
     as well as
    <
    a href='https://latexref.xyz/dev/mirroring.html'
    >
    mirror it
    <
    /a
    >
    .
    <
    /p
    >
    <
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    <title spaces=" "Default handler: &latex;
>
      2e: An unofficial reference manual
    </title>
    <subtitle spaces=" ">
      May 2024
    </subtitle>
    <author spaces=" ">
      <url>
        <urefurl>
          https://latexref.xyz
        </urefurl>
      </url>
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      Top
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      About this document
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  <top spaces=" ">
    <sectiontitleDefault handler: &latex;
>
      2e: An unofficial reference manual
    </sectiontitle>
    <para>
      This document is an unofficial reference manual (version of May 2024) for
Default handler: &latex;
      2e, a document preparation system.
    </para>
    <menu endspaces=" ">
      <menuentry>
        <menuleadingtext>
          *
        </menuleadingtext>
        <menunode>
          About this document
        </menunode>
        <menuseparator>
          ::
        </menuseparator>
        <menudescription>
          <pre xml:space="preserve">
            Bug reporting, etc.
          </pre>
        </menudescription>
      </menuentry>
      <menuentry>
        <menuleadingtext>
          *
        </menuleadingtext>
        <menunode>
          Overview
        </menunode>
        <menuseparator>
          ::
        </menuseparator>
        <menudescription>
          <pre xml:space="preserve">
            What is
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            ?
          </pre>
        </menudescription>
      </menuentry>
      <menuentry>
        <menuleadingtext>
          *
        </menuleadingtext>
        <menunode>
          Document classes
        </menunode>
        <menuseparator>
          ::
        </menuseparator>
        <menudescription>
          <pre xml:space="preserve">
            Some of the various classes available.
          </pre>
        </menudescription>
      </menuentry>
      <menuentry>
        <menuleadingtext>
          *
        </menuleadingtext>
        <menunode>
          Fonts
        </menunode>
        <menuseparator>
          ::
        </menuseparator>
        <menudescription>
          <pre xml:space="preserve">
            Italic, bold, typewriter, etc.
          </pre>
        </menudescription>
      </menuentry>
      <menuentry>
        <menuleadingtext>
          *
        </menuleadingtext>
        <menunode>
          Layout
        </menunode>
        <menuseparator>
          ::
        </menuseparator>
        <menudescription>
          <pre xml:space="preserve">
            Controlling the page layout.
          </pre>
        </menudescription>
      </menuentry>
      <menuentry>
        <menuleadingtext>
          *
        </menuleadingtext>
        <menunode>
          Sectioning
        </menunode>
        <menuseparator>
          ::
        </menuseparator>
        <menudescription>
          <pre xml:space="preserve">
            Parts, Chapters, Sections, etc.
          </pre>
        </menudescription>
      </menuentry>
      <menuentry>
        <menuleadingtext>
          *
        </menuleadingtext>
        <menunode>
          Cross references
        </menunode>
        <menuseparator>
          ::
        </menuseparator>
        <menudescription>
          <pre xml:space="preserve">
            Automatic referencing.
          </pre>
        </menudescription>
      </menuentry>
      <menuentry>
        <menuleadingtext>
          *
        </menuleadingtext>
        <menunode>
          Environments
        </menunode>
        <menuseparator>
          ::
        </menuseparator>
        <menudescription>
          <pre xml:space="preserve">
            Such as enumerate
            &
             itemize.
          </pre>
        </menudescription>
      </menuentry>
      <menuentry>
        <menuleadingtext>
          *
        </menuleadingtext>
        <menunode>
          Line breaking
        </menunode>
        <menuseparator>
          ::
        </menuseparator>
        <menudescription>
          <pre xml:space="preserve">
            Influencing line breaks.
          </pre>
        </menudescription>
      </menuentry>
      <menuentry>
        <menuleadingtext>
          *
        </menuleadingtext>
        <menunode>
          Page breaking
        </menunode>
        <menuseparator>
          ::
        </menuseparator>
        <menudescription>
          <pre xml:space="preserve">
            Influencing page breaks.
          </pre>
        </menudescription>
      </menuentry>
      <menuentry>
        <menuleadingtext>
          *
        </menuleadingtext>
        <menunode>
          Footnotes
        </menunode>
        <menuseparator>
          ::
        </menuseparator>
        <menudescription>
          <pre xml:space="preserve">
            How to produce footnotes.
          </pre>
        </menudescription>
      </menuentry>
      <menuentry>
        <menuleadingtext>
          *
        </menuleadingtext>
        <menunode>
          Definitions
        </menunode>
        <menuseparator>
          ::
        </menuseparator>
        <menudescription>
          <pre xml:space="preserve">
            Define your own commands, etc.
          </pre>
        </menudescription>
      </menuentry>
      <menuentry>
        <menuleadingtext>
          *
        </menuleadingtext>
        <menunode>
          Counters
        </menunode>
        <menuseparator>
          ::
        </menuseparator>
        <menudescription>
          <pre xml:space="preserve">
            Internal counters used by
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            .
          </pre>
        </menudescription>
      </menuentry>
      <menuentry>
        <menuleadingtext>
          *
        </menuleadingtext>
        <menunode>
          Lengths
        </menunode>
        <menuseparator>
          ::
        </menuseparator>
        <menudescription>
          <pre xml:space="preserve">
            The length commands.
          </pre>
        </menudescription>
      </menuentry>
      <menuentry>
        <menuleadingtext>
          *
        </menuleadingtext>
        <menunode>
          Making paragraphs
        </menunode>
        <menuseparator>
          ::
        </menuseparator>
        <menudescription>
          <pre xml:space="preserve">
            Paragraph commands.
          </pre>
        </menudescription>
      </menuentry>
      <menuentry>
        <menuleadingtext>
          *
        </menuleadingtext>
        <menunode>
          Math formulas
        </menunode>
        <menuseparator>
          ::
        </menuseparator>
        <menudescription>
          <pre xml:space="preserve">
            How to create mathematical formulas.
          </pre>
        </menudescription>
      </menuentry>
      <menuentry>
        <menuleadingtext>
          *
        </menuleadingtext>
        <menunode>
          Modes
        </menunode>
        <menuseparator>
          ::
        </menuseparator>
        <menudescription>
          <pre xml:space="preserve">
            Paragraph, Math or LR modes.
          </pre>
        </menudescription>
      </menuentry>
      <menuentry>
        <menuleadingtext>
          *
        </menuleadingtext>
        <menunode>
          Page styles
        </menunode>
        <menuseparator>
          ::
        </menuseparator>
        <menudescription>
          <pre xml:space="preserve">
            Various styles of page layout.
          </pre>
        </menudescription>
      </menuentry>
      <menuentry>
        <menuleadingtext>
          *
        </menuleadingtext>
        <menunode>
          Spaces
        </menunode>
        <menuseparator>
          ::
        </menuseparator>
        <menudescription>
          <pre xml:space="preserve">
            Horizontal and vertical space.
          </pre>
        </menudescription>
      </menuentry>
      <menuentry>
        <menuleadingtext>
          *
        </menuleadingtext>
        <menunode>
          Boxes
        </menunode>
        <menuseparator>
          ::
        </menuseparator>
        <menudescription>
          <pre xml:space="preserve">
            Making boxes.
          </pre>
        </menudescription>
      </menuentry>
      <menuentry>
        <menuleadingtext>
          *
        </menuleadingtext>
        <menunode>
          Graphics
        </menunode>
        <menuseparator>
          ::
        </menuseparator>
        <menudescription>
          <pre xml:space="preserve">
            Importing graphics from outside
Default handler: &latex;
            .
          </pre>
        </menudescription>
      </menuentry>
      <menuentry>
        <menuleadingtext>
          *
        </menuleadingtext>
        <menunode>
          Color
        </menunode>
        <menuseparator>
          ::
        </menuseparator>
        <menudescription>
          <pre xml:space="preserve">
            Defining and using colors.
          </pre>
        </menudescription>
      </menuentry>
      <menuentry>
        <menuleadingtext>
          *
        </menuleadingtext>
        <menunode>
          Special insertions
        </menunode>
        <menuseparator>
          ::
        </menuseparator>
        <menudescription>
          <pre xml:space="preserve">
            Inserting reserved and special characters.
          </pre>
        </menudescription>
      </menuentry>
      <menuentry>
        <menuleadingtext>
          *
        </menuleadingtext>
        <menunode>
          Splitting the input
        </menunode>
        <menuseparator>
          ::
        </menuseparator>
        <menudescription>
          <pre xml:space="preserve">
            Dealing with big files by splitting.
          </pre>
        </menudescription>
      </menuentry>
      <menuentry>
        <menuleadingtext>
          *
        </menuleadingtext>
        <menunode>
          Front/back matter
        </menunode>
        <menuseparator>
          ::
        </menuseparator>
        <menudescription>
          <pre xml:space="preserve">
            Tables of contents, glossaries, indexes.
          </pre>
        </menudescription>
      </menuentry>
      <menuentry>
        <menuleadingtext>
          *
        </menuleadingtext>
        <menunode>
          Letters
        </menunode>
        <menuseparator>
          ::
        </menuseparator>
        <menudescription>
          <pre xml:space="preserve">
            The
            <code>
              letter
            </code>
             class.
          </pre>
        </menudescription>
      </menuentry>
      <menuentry>
        <menuleadingtext>
          *
        </menuleadingtext>
        <menunode>
          Input/output
        </menunode>
        <menuseparator>
          ::
        </menuseparator>
        <menudescription>
          <pre xml:space="preserve">
            User interaction.
          </pre>
        </menudescription>
      </menuentry>
      <menuentry>
        <menuleadingtext>
          *
        </menuleadingtext>
        <menunode>
          Command line interface
        </menunode>
        <menuseparator>
          ::
        </menuseparator>
        <menudescription>
          <pre xml:space="preserve">
            Common command-line options.
          </pre>
        </menudescription>
      </menuentry>
      <menuentry>
        <menuleadingtext>
          *
        </menuleadingtext>
        <menunode>
          Document templates
        </menunode>
        <menuseparator>
          ::
        </menuseparator>
        <menudescription>
          <pre xml:space="preserve">
            Starter templates for various document classes.
          </pre>
        </menudescription>
      </menuentry>
      <menuentry>
        <menuleadingtext>
          *
        </menuleadingtext>
        <menunode>
          Index
        </menunode>
        <menuseparator>
          ::
        </menuseparator>
        <menudescription>
          <pre xml:space="preserve">
            General index.
          </pre>
        </menudescription>
      </menuentry>
    </menu>
  </top>
  <node name="About-this-document" spaces=" ">
    <nodename>
      About this document
    </nodename>
    <nodenext automatic="on">
      Overview
    </nodenext>
    <nodeprev automatic="on">
      Top
    </nodeprev>
    <nodeup automatic="on">
      Top
    </nodeup>
  </node>
  <chapter spaces=" ">
    <sectiontitle>
      About this document
    </sectiontitle>
    <cindex index="cp" spaces=" ">
      <indexterm index="cp" number="1">
        home page for manual
      </indexterm>
    </cindex>
    <para>
      This is an unofficial reference manual for the
Default handler: &latex;
      2e document preparation system, which is a macro package for the
Default handler: &tex;
       typesetting program (
      <pxref label="Overview">
        <xrefnodename>
          Overview
        </xrefnodename>
      </pxref>
      ).
    </para>
    <para>
      This document
Default handler: &textrsquo;
      s home page is
      <url>
        <urefurl>
          https://latexref.xyz
        </urefurl>
      </url>
      ; it has separate web pages for each topic. Alternatively.
      <url>
        <urefurl>
          https://latexref.xyz/dev/latex2e.html
        </urefurl>
      </url>
       has the entire document on a single page. For other output formats, the sources, and plenty more information, see
      <url>
        <urefurl>
          https://latexref.xyz/dev/
        </urefurl>
      </url>
      .
    </para>
    <cindex index="cp" spaces=" ">
      <indexterm index="cp" number="2"Default handler: &latex;
>
         vs.
Default handler: &noeos;
Default handler: &latex;
        2e
      </indexterm>
    </cindex>
    <para>
      In this document, we will mostly just use
Default handler: &textlsquo;
Default handler: &latex;
Default handler: &textrsquo;
       rather than
Default handler: &textlsquo;
Default handler: &latex;
      2e
Default handler: &textrsquo;
      , since the previous version of
Default handler: &latex;
Default handler: &nbsp;
      (2.09) was frozen decades ago.
    </para>
    <cindex index="cp" spaces=" ">
      <indexterm index="cp" number="3">
        unofficial nature of this manual
      </indexterm>
    </cindex>
    <cindex index="cp" spaces=" ">
      <indexterm index="cp" number="4"Default handler: &latex;
>
         Project team
      </indexterm>
    </cindex>
    <findex index="fn" spaces=" ">
      <indexterm index="fn" number="1" mergedindex="cp">
        <email>
          <emailaddress>
            latexrefman
Default handler: &arobase;
            tug.org
          </emailaddress>
        </email>
        <r>
          email address
        </r>
      </indexterm>
    </findex>
    <paraDefault handler: &latex;
>
       is maintained by a group of volunteers (
      <url>
        <urefurl>
          https://latex-project.org
        </urefurl>
      </url>
      ). The official documentation written by the
Default handler: &latex;
       project is available from their web site. The present document is completely unofficial and has not been written or reviewed by the
Default handler: &latex;
       maintainers.
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="5">
          bug reporting
        </indexterm>
      </cindex>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="6">
          reporting bugs
        </indexterm>
      </cindex>
       Do not send bug reports or anything else about this document to them. Instead, please send all comments to
      <email>
        <emailaddress>
          latexrefman
Default handler: &arobase;
          tug.org
        </emailaddress>
      </email>
      . This is a public list; you can (un)subscribe, view the archives, etc., at
      <url>
        <urefurl>
          https://lists.tug.org/latexrefman
        </urefurl>
      </url>
      .
    </para>
    <para>
      This document is a reference, not a tutorial. There is a vast array of other information available about
Default handler: &latex;
      , at all levels. Here are a few introductions.
    </para>
    <table commandarg="url" spaces=" " endspaces=" ">
      <tableentry>
        <tableterm>
          <item spaces=" ">
            <itemformat command="url">
              https://ctan.org/pkg/latex-doc-ptr
            </itemformat>
          </item>
        </tableterm>
        <tableitem>
          <findex index="fn" spaces=" ">
            <indexterm index="fn" number="2" mergedindex="cp">
              latex-doc-ptr
              <r>
                document
              </r>
            </indexterm>
          </findex>
          <para>
            Two pages of recommended references to
Default handler: &latex;
             documentation.
          </para>
        </tableitem>
      </tableentry>
      <tableentry>
        <tableterm>
          <item spaces=" ">
            <itemformat command="url">
              https://ctan.org/pkg/first-latex-doc
            </itemformat>
          </item>
        </tableterm>
        <tableitem>
          <findex index="fn" spaces=" ">
            <indexterm index="fn" number="3" mergedindex="cp">
              first-latex-doc
              <r>
                document
              </r>
            </indexterm>
          </findex>
          <para>
            Writing your first document, with a bit of both text and math.
          </para>
        </tableitem>
      </tableentry>
      <tableentry>
        <tableterm>
          <item spaces=" ">
            <itemformat command="url">
              https://ctan.org/pkg/lshort
            </itemformat>
          </item>
        </tableterm>
        <tableitem>
          <findex index="fn" spaces=" ">
            <indexterm index="fn" number="4" mergedindex="cp">
              lshort
              <r>
                document
              </r>
            </indexterm>
          </findex>
          <para>
            A longer introduction to
Default handler: &latex;
            , translated to many languages.
          </para>
        </tableitem>
      </tableentry>
      <tableentry>
        <tableterm>
          <item spaces=" ">
            <itemformat command="url">
              https://tug.org/begin.html
            </itemformat>
          </item>
        </tableterm>
        <tableitem>
          <para>
            Overview of getting started with
Default handler: &tex;
             and
Default handler: &latex;
            .
          </para>
        </tableitem>
      </tableentry>
    </table>
  </chapter>
  <node name="Overview" spaces=" ">
    <nodename>
      Overview
    </nodename>
    <nodenext automatic="on">
      Document classes
    </nodenext>
    <nodeprev automatic="on">
      About this document
    </nodeprev>
    <nodeup automatic="on">
      Top
    </nodeup>
  </node>
  <chapter spaces=" ">
    <sectiontitle>
      Overview of
Default handler: &latex;
    </sectiontitle>
    <cindex index="cp" spaces=" ">
      <indexterm index="cp" number="7">
        overview of
Default handler: &latex;
      </indexterm>
    </cindex>
    <cindex index="cp" spaces=" ">
      <indexterm index="cp" number="8">
        basics of
Default handler: &latex;
      </indexterm>
    </cindex>
    <cindex index="cp" spaces=" ">
      <indexterm index="cp" number="9">
        Knuth, Donald E.
      </indexterm>
    </cindex>
    <cindex index="cp" spaces=" ">
      <indexterm index="cp" number="10">
        Lamport, Leslie
      </indexterm>
    </cindex>
    <cindex index="cp" spaces=" ">
      <indexterm index="cp" number="11"Default handler: &latex;
>
         overview
      </indexterm>
    </cindex>
    <paraDefault handler: &latex;
>
       is a system for typesetting documents. It was originally created by Leslie Lamport in 1984, but has been maintained by a group of volunteers for many years now (
      <url>
        <urefurl>
          https://latex-project.org
        </urefurl>
      </url>
      ). It is widely used, particularly but not exclusively for mathematical and technical documents.
    </para>
    <cindex index="cp" spaces=" ">
      <indexterm index="cp" number="12">
        UTF-8, default
Default handler: &latex;
         input encoding
      </indexterm>
    </cindex>
    <para>
      A
Default handler: &latex;
       user writes an input file containing text to be typeset along with interspersed commands. The default encoding for the text is UTF-8 (as of 2018). The commands specify, for example, how the text should be formatted.
    </para>
    <paraDefault handler: &latex;
>
       is implemented as a set of so-called
Default handler: &textldquo;
      macros
Default handler: &textrdquo;
       (a
Default handler: &tex;
      <dfn>
        format
      </dfn>
      ) which use Donald
Default handler: &nbsp;
      E. Knuth
Default handler: &textrsquo;
      s
Default handler: &tex;
       typesetting program or one of its derivatives, collectively known as
Default handler: &textldquo;
      engines
Default handler: &textrdquo;
      . Thus, the user produces output, typically PDF, by giving the input file to a
Default handler: &tex;
       engine. The following sections describe all this in more detail.
    </para>
    <para>
      The term
Default handler: &latex;
       is also sometimes used to mean the language in which the input document is marked up, that is, to mean the set of commands available to a
Default handler: &latex;
       user.
    </para>
    <cindex index="cp" spaces=" ">
      <indexterm index="cp" number="13">
        Lamport
Default handler: &tex;
      </indexterm>
    </cindex>
    <cindex index="cp" spaces=" ">
      <indexterm index="cp" number="14">
        pronunciation
      </indexterm>
    </cindex>
    <para>
      The name
Default handler: &latex;
       is short for
Default handler: &textldquo;
      Lamport
Default handler: &tex;
Default handler: &textrdquo;
      . It is pronounced LAH-teck or LAY-teck, or sometimes LAY-tecks. Inside a document, produce the logo with
      <code>
        \LaTeX
      </code>
      . Where use of the logo is not sensible, such as in plain text, write it as
      <samp>
        LaTeX
      </samp>
      .
    </para>
    <menu endspaces=" ">
      <menuentry>
        <menuleadingtext>
          *
        </menuleadingtext>
        <menunode>
          Starting and ending
        </menunode>
        <menuseparator>
          ::
        </menuseparator>
        <menudescription>
          <pre xml:space="preserve">
            The standard beginning and end of a document.
          </pre>
        </menudescription>
      </menuentry>
      <menuentry>
        <menuleadingtext>
          *
        </menuleadingtext>
        <menunode>
          Output files
        </menunode>
        <menuseparator>
          ::
        </menuseparator>
        <menudescription>
          <pre xml:space="preserve">
            Files produced.
          </pre>
        </menudescription>
      </menuentry>
      <menuentry>
        <menuleadingtext>
          *
        </menuleadingtext>
        <menunodeDefault handler: &tex;
>
           engines
        </menunode>
        <menuseparator>
          ::
        </menuseparator>
        <menudescription>
          <pre xml:space="preserve">
            Programs that can compile
Default handler: &tex;
             and
Default handler: &latex;
            .
          </pre>
        </menudescription>
      </menuentry>
      <menuentry>
        <menuleadingtext>
          *
        </menuleadingtext>
        <menunode>
          Input text
        </menunode>
        <menuseparator>
          ::
        </menuseparator>
        <menudescription>
          <pre xml:space="preserve">
            Input encodings and special characters.
          </pre>
        </menudescription>
      </menuentry>
      <menuentry>
        <menuleadingtext>
          *
        </menuleadingtext>
        <menunodeDefault handler: &latex;
>
           command syntax
        </menunode>
        <menuseparator>
          ::
        </menuseparator>
        <menudescription>
          <pre xml:space="preserve">
            General syntax of
Default handler: &latex;
             commands.
          </pre>
        </menudescription>
      </menuentry>
      <menuentry>
        <menuleadingtext>
          *
        </menuleadingtext>
        <menunode>
          Environment syntax
        </menunode>
        <menuseparator>
          ::
        </menuseparator>
        <menudescription>
          <pre xml:space="preserve">
            \begin
Default handler: &lbrace;
            envname
Default handler: &rbrace;
             ... \end
Default handler: &lbrace;
            envname
Default handler: &rbrace;
            .
          </pre>
        </menudescription>
      </menuentry>
      <menuentry>
        <menuleadingtext>
          *
        </menuleadingtext>
        <menunode>
          \DocumentMetadata
        </menunode>
        <menuseparator>
          ::
        </menuseparator>
        <menudescription>
          <pre xml:space="preserve">
            Towards accessible PDF output.
          </pre>
        </menudescription>
      </menuentry>
      <menuentry>
        <menuleadingtext>
          *
        </menuleadingtext>
        <menunode>
          CTAN
        </menunode>
        <menuseparator>
          ::
        </menuseparator>
        <menudescription>
          <pre xml:space="preserve">
            The TeX world
Default handler: &textrsquo;
            s general repository.
          </pre>
        </menudescription>
      </menuentry>
    </menu>
    <node name="Starting-and-ending" spaces=" ">
      <nodename>
        Starting and ending
      </nodename>
      <nodenext automatic="on">
        Output files
      </nodenext>
      <nodeup automatic="on">
        Overview
      </nodeup>
    </node>
    <section spaces=" ">
      <sectiontitle>
        Starting and ending
      </sectiontitle>
      <anchor name="Starting-_0026-ending">
        Starting
        &
         ending
      </anchor>
Default handler: <!-- c old name -->
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="15">
          starting and ending
        </indexterm>
      </cindex>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="16">
          ending and starting
        </indexterm>
      </cindex>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="17">
          hello, world
        </indexterm>
      </cindex>
      <paraDefault handler: &latex;
>
         files have a simple global structure, with a standard beginning and ending. Here is a small example:
      </para>
      <example endspaces=" ">
        <pre xml:space="preserve">
          \documentclass
Default handler: &lbrace;
          article
Default handler: &rbrace;
           \begin
Default handler: &lbrace;
          document
Default handler: &rbrace;
           Hello, \LaTeX\ world. \end
Default handler: &lbrace;
          document
Default handler: &rbrace;
        </pre>
      </example>
      <noindent/>
      <para>
        Every
Default handler: &latex;
         document has a
        <code>
          \begin
Default handler: &lbrace;
          document
Default handler: &rbrace;
        </code>
         line and an
        <code>
          \end
Default handler: &lbrace;
          document
Default handler: &rbrace;
        </code>
         line.
      </para>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="18">
          document class, defined
        </indexterm>
      </cindex>
      <noindent/>
      <para>
        Here, the
        <samp>
          article
        </samp>
         is the
        <dfn>
          document class
        </dfn>
        . It is implemented in a file
        <file>
          article.cls
        </file>
        . You can use any document class available on your system. A few document classes are defined by
Default handler: &latex;
         itself, and a vast array of others are available.
        <xref label="Document-classes">
          <xrefnodename>
            Document classes
          </xrefnodename>
        </xref>
        .
      </para>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="19">
          preamble, defined
        </indexterm>
      </cindex>
      <para>
        You can include other
Default handler: &latex;
         commands between the
        <code>
          \documentclass
        </code>
         and the
        <code>
          \begin
Default handler: &lbrace;
          document
Default handler: &rbrace;
        </code>
         commands. This area is called the
        <dfn>
          preamble
        </dfn>
        .
      </para>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="20">
          environment
        </indexterm>
      </cindex>
      <para>
        The
        <code>
          \begin
Default handler: &lbrace;
          document
Default handler: &rbrace;
        </code>
Default handler: &dots;
        <code>
          \end
Default handler: &lbrace;
          document
Default handler: &rbrace;
        </code>
         pair defines an
        <dfn>
          environment
        </dfn>
        ; the
        <samp>
          document
        </samp>
         environment (and no others) is required in all
Default handler: &latex;
         documents (
        <pxref label="document">
          <xrefnodename>
            document
          </xrefnodename>
        </pxref>
        ).
Default handler: &latex;
         provides many environments that are documented here (
        <pxref label="Environments">
          <xrefnodename>
            Environments
          </xrefnodename>
        </pxref>
        ). Many more are available to you from external packages, most importantly those available at CTAN (
        <pxref label="CTAN">
          <xrefnodename>
            CTAN
          </xrefnodename>
        </pxref>
        ).
      </para>
      <para>
        The following sections discuss how to produce PDF or other output from a
Default handler: &latex;
         input file.
      </para>
    </section>
    <node name="Output-files" spaces=" ">
      <nodename>
        Output files
      </nodename>
      <nodenext automatic="on"Default handler: &tex;
>
         engines
      </nodenext>
      <nodeprev automatic="on">
        Starting and ending
      </nodeprev>
      <nodeup automatic="on">
        Overview
      </nodeup>
    </node>
    <section spaces=" ">
      <sectiontitle>
        Output files
      </sectiontitle>
      <paraDefault handler: &latex;
>
         produces a main output file and at least two auxiliary files. The main output file
Default handler: &textrsquo;
        s name ends in either
        <file>
          .dvi
        </file>
         or
        <file>
          .pdf
        </file>
        .
      </para>
      <table commandarg="code" spaces=" " endspaces=" ">
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                .dvi
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <findex index="fn" spaces=" ">
              <indexterm index="fn" number="5" mergedindex="cp">
                .dvi
                <r>
                  file
                </r>
              </indexterm>
            </findex>
            <findex index="fn" spaces=" ">
              <indexterm index="fn" number="6" mergedindex="cp">
                latex
                <r>
                  command
                </r>
              </indexterm>
            </findex>
            <findex index="fn" spaces=" ">
              <indexterm index="fn" number="7" mergedindex="cp">
                xdvi
                <r>
                  command
                </r>
              </indexterm>
            </findex>
            <findex index="fn" spaces=" ">
              <indexterm index="fn" number="8" mergedindex="cp">
                dvips
                <r>
                  command
                </r>
              </indexterm>
            </findex>
            <findex index="fn" spaces=" ">
              <indexterm index="fn" number="9" mergedindex="cp">
                dvipdfmx
                <r>
                  command
                </r>
              </indexterm>
            </findex>
            <findex index="fn" spaces=" ">
              <indexterm index="fn" number="10" mergedindex="cp">
                dvitype
                <r>
                  command
                </r>
              </indexterm>
            </findex>
            <anchor name="output-files-dvi">
              output files dvi
            </anchor>
            <para>
              If
Default handler: &latex;
               is invoked with the system command
              <command>
                latex
              </command>
               then it produces a DeVice Independent file, with extension
              <file>
                .dvi
              </file>
              . You can view this file with a command such as
              <command>
                xdvi
              </command>
              , or convert it to a PostScript
              <code>
                .ps
              </code>
               file with
              <command>
                dvips
              </command>
               or to a Portable Document Format
              <code>
                .pdf
              </code>
               file with
              <command>
                dvipdfmx
              </command>
              . The contents of the file can be dumped in human-readable form with
              <command>
                dvitype
              </command>
              . A vast array of other DVI utility programs are available (
              <url>
                <urefurl>
                  https://mirror.ctan.org/dviware
                </urefurl>
              </url>
              ).
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                .pdf
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <findex index="fn" spaces=" ">
              <indexterm index="fn" number="11" mergedindex="cp">
                .pdf
                <r>
                  file
                </r>
              </indexterm>
            </findex>
            <cindex index="cp" spaces=" ">
              <indexterm index="cp" number="21">
                pdf
Default handler: &tex;
              </indexterm>
            </cindex>
            <findex index="fn" spaces=" ">
              <indexterm index="fn" number="12" mergedindex="cp">
                pdflatex
                <r>
                  command
                </r>
              </indexterm>
            </findex>
            <anchor name="output-files-pdf">
              output files pdf
            </anchor>
            <para>
              If
Default handler: &latex;
               is invoked via the system command
              <command>
                pdflatex
              </command>
              , among other commands (
              <pxref label="TeX-engines">
                <xrefnodenameDefault handler: &tex;
>
                   engines
                </xrefnodename>
              </pxref>
              ), then the main output is a Portable Document Format (PDF) file. Typically this is a self-contained file, with all fonts and images included.
            </para>
          </tableitem>
        </tableentry>
      </table>
      <paraDefault handler: &latex;
>
         always produces at least two additional files.
      </para>
      <table commandarg="code" spaces=" " endspaces=" ">
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                .log
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <cindex index="cp" spaces=" ">
              <indexterm index="cp" number="22">
                transcript file
              </indexterm>
            </cindex>
            <cindex index="cp" spaces=" ">
              <indexterm index="cp" number="23">
                log file
              </indexterm>
            </cindex>
            <findex index="fn" spaces=" ">
              <indexterm index="fn" number="13" mergedindex="cp">
                .log
                <r>
                  file
                </r>
              </indexterm>
            </findex>
            <anchor name="output-files-log">
              output files log
            </anchor>
            <para>
              This transcript file contains summary information such as a list of loaded packages. It also includes diagnostic messages and perhaps additional information for any errors.
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                .aux
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <cindex index="cp" spaces=" ">
              <indexterm index="cp" number="24">
                auxiliary file
              </indexterm>
            </cindex>
            <findex index="fn" spaces=" ">
              <indexterm index="fn" number="14" mergedindex="cp">
                .aux
                <r>
                  file
                </r>
              </indexterm>
            </findex>
            <cindex index="cp" spaces=" ">
              <indexterm index="cp" number="25">
                cross references, resolving
              </indexterm>
            </cindex>
            <cindex index="cp" spaces=" ">
              <indexterm index="cp" number="26">
                forward references, resolving
              </indexterm>
            </cindex>
            <cindex index="cp" spaces=" ">
              <indexterm index="cp" number="27">
                references, resolving forward
              </indexterm>
            </cindex>
            <anchor name="output-files-aux">
              output files aux
            </anchor>
            <para>
              Auxiliary information is used by
Default handler: &latex;
               for things such as cross references. For example, the first time that
Default handler: &latex;
               finds a forward reference
Default handler: &textmdash;
              a cross reference to something that has not yet appeared in the source
Default handler: &textmdash;
              it will appear in the output as a doubled question mark
              <code>
                ??
              </code>
              . When the referred-to spot does eventually appear in the source then
Default handler: &latex;
               writes its location information to this
              <code>
                .aux
              </code>
               file. On the next invocation,
Default handler: &latex;
               reads the location information from this file and uses it to resolve the reference, replacing the double question mark with the remembered location.
            </para>
          </tableitem>
        </tableentry>
      </table>
      <findex index="fn" spaces=" ">
        <indexterm index="fn" number="15" mergedindex="cp">
          .lof
          <r>
            file
          </r>
        </indexterm>
      </findex>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="28">
          list of figures file
        </indexterm>
      </cindex>
      <findex index="fn" spaces=" ">
        <indexterm index="fn" number="16" mergedindex="cp">
          .lot
          <r>
            file
          </r>
        </indexterm>
      </findex>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="29">
          list of tables file
        </indexterm>
      </cindex>
      <findex index="fn" spaces=" ">
        <indexterm index="fn" number="17" mergedindex="cp">
          .toc
          <r>
            file
          </r>
        </indexterm>
      </findex>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="30">
          table of contents file
        </indexterm>
      </cindex>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="31">
          contents file
        </indexterm>
      </cindex>
      <paraDefault handler: &latex;
>
         may produce yet more files, characterized by the filename ending. These include a
        <code>
          .lof
        </code>
         file that is used to make a list of figures, a
        <code>
          .lot
        </code>
         file used to make a list of tables, and a
        <code>
          .toc
        </code>
         file used to make a table of contents (
        <pxref label="Table-of-contents-etc_002e">
          <xrefnodename>
            Table of contents etc.
          </xrefnodename>
        </pxref>
        ). A particular class may create others; the list is open-ended.
      </para>
    </section>
    <node name="TeX-engines" spaces=" ">
      <nodenameDefault handler: &tex;
>
         engines
      </nodename>
      <nodenext automatic="on">
        Input text
      </nodenext>
      <nodeprev automatic="on">
        Output files
      </nodeprev>
      <nodeup automatic="on">
        Overview
      </nodeup>
    </node>
    <section spaces=" ">
      <sectiontitleDefault handler: &tex;
>
         engines
      </sectiontitle>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="32">
          engines,
Default handler: &tex;
        </indexterm>
      </cindex>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="33">
          implementations of
Default handler: &tex;
        </indexterm>
      </cindex>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="34">
          UTF-8, engine support for
        </indexterm>
      </cindex>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="35">
          Unicode input, native
        </indexterm>
      </cindex>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="36">
          TrueType fonts
        </indexterm>
      </cindex>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="37">
          OpenType fonts
        </indexterm>
      </cindex>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="38"Default handler: &tex;
>
           format (
          <code>
            .fmt
          </code>
          ) files
        </indexterm>
      </cindex>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="39"Default handler: &latex;
>
           format (
          <code>
            .fmt
          </code>
          ) files
        </indexterm>
      </cindex>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="40">
          format files,
Default handler: &tex;
        </indexterm>
      </cindex>
      <findex index="fn" spaces=" ">
        <indexterm index="fn" number="18" mergedindex="cp">
          .fmt
          <r>
            file
          </r>
        </indexterm>
      </findex>
      <paraDefault handler: &latex;
>
         is a large set of commands (macros) that is executed by a
Default handler: &tex;
         program (
        <pxref label="Overview">
          <xrefnodename>
            Overview
          </xrefnodename>
        </pxref>
        ). Such a set of commands is called a
        <dfn>
          format
        </dfn>
        , and is embodied in a binary
        <code>
          .fmt
        </code>
         file, which can be read much more quickly than the corresponding
Default handler: &tex;
         source.
      </para>
      <para>
        This section gives a terse overview of the
Default handler: &tex;
         programs that are commonly available (see also
        <ref label="Command-line-interface">
          <xrefnodename>
            Command line interface
          </xrefnodename>
        </ref>
        ).
      </para>
      <ftable commandarg="code" spaces=" " endspaces=" ">
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                <indexterm index="fn" number="19" mergedindex="cp">
                  latex
                </indexterm>
                latex
              </itemformat>
            </item>
            <itemx spaces=" ">
              <itemformat command="code">
                <indexterm index="fn" number="20" mergedindex="cp">
                  pdflatex
                </indexterm>
                pdflatex
              </itemformat>
            </itemx>
          </tableterm>
          <tableitem>
            <findex index="fn" spaces=" ">
              <indexterm index="fn" number="21" mergedindex="cp">
                etex
                <r>
                  command
                </r>
              </indexterm>
            </findex>
            <cindex index="cp" spaces=" ">
              <indexterm index="cp" number="41">
                pdf
Default handler: &tex;
                 engine
              </indexterm>
            </cindex>
            <cindex index="cp" spaces=" ">
              <indexterm index="cp" number="42">
                e-
Default handler: &tex;
              </indexterm>
            </cindex>
            <anchor name="tex-engines-latex">
              tex engines latex
            </anchor>
            <para>
              In
Default handler: &tex;
               Live (
              <url>
                <urefurl>
                  https://tug.org/texlive
                </urefurl>
              </url>
              ), if
Default handler: &latex;
               is invoked via either the system command
              <command>
                latex
              </command>
               or
              <command>
                pdflatex
              </command>
              , then the pdf
Default handler: &tex;
               engine is run (
              <url>
                <urefurl>
                  https://ctan.org/pkg/pdftex
                </urefurl>
              </url>
              ). When invoked as
              <command>
                latex
              </command>
              , the main output is a
              <file>
                .dvi
              </file>
               file; as
              <command>
                pdflatex
              </command>
              , the main output is a
              <file>
                .pdf
              </file>
               file.
            </para>
            <para>
              pdf
Default handler: &tex;
               incorporates the e-
Default handler: &tex;
               extensions to Knuth
Default handler: &textrsquo;
              s original program (
              <url>
                <urefurl>
                  https://ctan.org/pkg/etex
                </urefurl>
              </url>
              ), including additional programming features and bi-directional typesetting, and has plenty of extensions of its own. e-
Default handler: &tex;
               is available on its own as the system command
              <command>
                etex
              </command>
              , but this is plain
Default handler: &tex;
               (and produces
              <file>
                .dvi
              </file>
              ).
            </para>
            <para>
              In other
Default handler: &tex;
               distributions,
              <command>
                latex
              </command>
               may invoke e-
Default handler: &tex;
               rather than pdf
Default handler: &tex;
              . In any case, the e-
Default handler: &tex;
               extensions can be assumed to be available in
Default handler: &latex;
              , and a few extensions beyond e-
Default handler: &tex;
              , particularly for file manipulation.
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                <indexterm index="fn" number="22" mergedindex="cp">
                  lualatex
                </indexterm>
                lualatex
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <cindex index="cp" spaces=" ">
              <indexterm index="cp" number="43">
                Lua
Default handler: &tex;
              </indexterm>
            </cindex>
            <anchor name="tex-engines-lualatex">
              tex engines lualatex
            </anchor>
            <para>
              If
Default handler: &latex;
               is invoked via the system command
              <command>
                lualatex
              </command>
              , the Lua
Default handler: &tex;
               engine is run (
              <url>
                <urefurl>
                  https://ctan.org/pkg/luatex
                </urefurl>
              </url>
              ). This program allows code written in the scripting language Lua (
              <url>
                <urefurl>
                  http://luatex.org
                </urefurl>
              </url>
              ) to interact with
Default handler: &tex;
Default handler: &textrsquo;
              s typesetting. Lua
Default handler: &tex;
               handles UTF-8 Unicode input natively, can handle OpenType and TrueType fonts, and produces a
              <file>
                .pdf
              </file>
               file by default. There is also
              <command>
                dvilualatex
              </command>
               to produce a
              <file>
                .dvi
              </file>
               file.
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                <indexterm index="fn" number="23" mergedindex="cp">
                  xelatex
                </indexterm>
                xelatex
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <cindex index="cp" spaces=" ">
              <indexterm index="cp" number="44">
                Xe
Default handler: &tex;
              </indexterm>
            </cindex>
            <findex index="fn" spaces=" ">
              <indexterm index="fn" number="24" mergedindex="cp">
                .xdv
                <r>
                  file
                </r>
              </indexterm>
            </findex>
            <findex index="fn" spaces=" ">
              <indexterm index="fn" number="25" mergedindex="cp">
                xdvipdfmx
              </indexterm>
            </findex>
            <anchor name="tex-engines-xelatex">
              tex engines xelatex
            </anchor>
            <para>
              If
Default handler: &latex;
               is invoked with the system command
              <command>
                xelatex
              </command>
              , the Xe
Default handler: &tex;
               engine is run (
              <url>
                <urefurl>
                  https://tug.org/xetex
                </urefurl>
              </url>
              ). Like Lua
Default handler: &tex;
              , Xe
Default handler: &tex;
               natively supports UTF-8 Unicode and TrueType and OpenType fonts, though the implementation is completely different, mainly using external libraries instead of internal code. Xe
Default handler: &tex;
               produces a
              <file>
                .pdf
              </file>
               file as output; it does not support DVI output.
            </para>
            <para>
              Internally, Xe
Default handler: &tex;
               creates an
              <code>
                .xdv
              </code>
               file, a variant of DVI, and translates that to PDF using the (
              <code>
                x
              </code>
              )
              <code>
                dvipdfmx
              </code>
               program, but this process is automatic. The
              <code>
                .xdv
              </code>
               file is only useful for debugging.
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                <indexterm index="fn" number="26" mergedindex="cp">
                  hilatex
                </indexterm>
                hilatex
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <cindex index="cp" spaces=" ">
              <indexterm index="cp" number="45">
                Hi
Default handler: &tex;
              </indexterm>
            </cindex>
            <cindex index="cp" spaces=" ">
              <indexterm index="cp" number="46">
                HINT format
              </indexterm>
            </cindex>
            <cindex index="cp" spaces=" ">
              <indexterm index="cp" number="47">
                mobile output
              </indexterm>
            </cindex>
            <para>
              If
Default handler: &latex;
               is invoked via the system command
              <command>
                hilatex
              </command>
              , the Hi
Default handler: &tex;
               engine is run (
              <url>
                <urefurl>
                  https://ctan.org/pkg/hitex
                </urefurl>
              </url>
              ). This program produces its own format, named HINT, designed especially for high-quality typesetting on mobile devices.
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                <indexterm index="fn" number="27" mergedindex="cp">
                  platex
                </indexterm>
                platex
              </itemformat>
            </item>
            <itemx spaces=" ">
              <itemformat command="code">
                <indexterm index="fn" number="28" mergedindex="cp">
                  uplatex
                </indexterm>
                uplatex
              </itemformat>
            </itemx>
          </tableterm>
          <tableitem>
            <para>
              These commands provide significant additional support for Japanese and other languages; the
              <code>
                u
              </code>
               variant supports Unicode. See
              <url>
                <urefurl>
                  https://ctan.org/pkg/ptex
                </urefurl>
              </url>
               and
              <url>
                <urefurl>
                  https://ctan.org/pkg/uptex
                </urefurl>
              </url>
              .
            </para>
          </tableitem>
        </tableentry>
      </ftable>
      <para>
        As of 2019, there is a companion
        <code>
          -dev
        </code>
         command and format for all of the above, except
        <code>
          hitex
        </code>
        :
      </para>
      <ftable commandarg="code" spaces=" " endspaces=" ">
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                <indexterm index="fn" number="29" mergedindex="cp">
                  dvilualatex-dev
                </indexterm>
                dvilualatex-dev
              </itemformat>
            </item>
            <itemx spaces=" ">
              <itemformat command="code">
                <indexterm index="fn" number="30" mergedindex="cp">
                  latex-dev
                </indexterm>
                latex-dev
              </itemformat>
            </itemx>
            <itemx spaces=" ">
              <itemformat command="code">
                <indexterm index="fn" number="31" mergedindex="cp">
                  lualatex-dev
                </indexterm>
                lualatex-dev
              </itemformat>
            </itemx>
            <itemx spaces=" ">
              <itemformat command="code">
                <indexterm index="fn" number="32" mergedindex="cp">
                  pdflatex-dev
                </indexterm>
                pdflatex-dev
              </itemformat>
            </itemx>
            <itemx spaces=" ">
              <itemformat command="code">
                <indexterm index="fn" number="33" mergedindex="cp">
                  platex-dev
                </indexterm>
                platex-dev
              </itemformat>
            </itemx>
            <itemx spaces=" ">
              <itemformat command="code">
                <indexterm index="fn" number="34" mergedindex="cp">
                  uplatex-dev
                </indexterm>
                uplatex-dev
              </itemformat>
            </itemx>
            <itemx spaces=" ">
              <itemformat command="code">
                <indexterm index="fn" number="35" mergedindex="cp">
                  xelatex-dev
                </indexterm>
                xelatex-dev
              </itemformat>
            </itemx>
          </tableterm>
          <tableitem>
            <cindex index="cp" spaces=" ">
              <indexterm index="cp" number="48">
                release candidates
              </indexterm>
            </cindex>
            <cindex index="cp" spaces=" ">
              <indexterm index="cp" number="49">
                prerelease testing
              </indexterm>
            </cindex>
            <para>
              These are candidates for an upcoming
Default handler: &latex;
               release. The main purpose is to find and address compatibility problems before an official release.
            </para>
            <para>
              These
              <code>
                -dev
              </code>
               formats make it easy for anyone to help test documents and code: you can run, say,
              <code>
                pdflatex-dev
              </code>
               instead of
              <code>
                pdflatex
              </code>
              , without changing anything else in your environment. Indeed, it is easiest and most helpful to always run the
              <code>
                -dev
              </code>
               versions instead of bothering to switch back and forth. During quiet times after a release, the commands will be equivalent.
            </para>
            <para>
              These are not daily snapshots or untested development code. They undergo the same extensive regression testing by the
Default handler: &latex;
               team before being released.
            </para>
            <para>
              For more information, see
Default handler: &textldquo;
              The
Default handler: &latex;
               release workflow and the
Default handler: &latex;
              <code>
                dev
              </code>
               formats
Default handler: &textrdquo;
               by Frank Mittelbach,
              <cite>
                TUGboat
              </cite>
               40:2,
              <url>
                <urefurl>
                  https://tug.org/TUGboat/tb40-2/tb125mitt-dev.pdf
                </urefurl>
              </url>
              .
            </para>
          </tableitem>
        </tableentry>
      </ftable>
    </section>
    <node name="Input-text" spaces=" ">
      <nodename>
        Input text
      </nodename>
      <nodenext automatic="on"Default handler: &latex;
>
         command syntax
      </nodenext>
      <nodeprev automatic="on"Default handler: &tex;
>
         engines
      </nodeprev>
      <nodeup automatic="on">
        Overview
      </nodeup>
    </node>
    <section spaces=" ">
      <sectiontitle>
        Input text
      </sectiontitle>
      <para>
        To a first approximation, most input characters in
Default handler: &latex;
         print as themselves. But there are exceptions, as discussed in the following sections.
      </para>
      <menu endspaces=" ">
        <menuentry>
          <menuleadingtext>
            *
          </menuleadingtext>
          <menunode>
            Input encodings
          </menunode>
          <menuseparator>
            ::
          </menuseparator>
          <menudescription>
            <pre xml:space="preserve"/>
          </menudescription>
        </menuentry>
        <menuentry>
          <menuleadingtext>
            *
          </menuleadingtext>
          <menunode>
            Ligatures
          </menunode>
          <menuseparator>
            ::
          </menuseparator>
          <menudescription>
            <pre xml:space="preserve">
              Combined characters: ff fi fl ffi ffl
Default handler: &textldquo;
Default handler: &textrdquo;
Default handler: &textndash;
Default handler: &textmdash;
Default handler: &textlsquo;
              !
Default handler: &textlsquo;
              ?
            </pre>
          </menudescription>
        </menuentry>
        <menuentry>
          <menuleadingtext>
            *
          </menuleadingtext>
          <menunode>
            Special characters
          </menunode>
          <menuseparator>
            ::
          </menuseparator>
          <menudescription>
            <pre xml:space="preserve">
              With special meaning:
              <code>
                \
Default handler: &lbrace;
Default handler: &rbrace;
                 % $
                &
                 _ ^ # ~
              </code>
            </pre>
          </menudescription>
        </menuentry>
      </menu>
      <node name="Input-encodings" spaces=" ">
        <nodename>
          Input encodings
        </nodename>
        <nodenext automatic="on">
          Ligatures
        </nodenext>
        <nodeup automatic="on">
          Input text
        </nodeup>
      </node>
      <subsection spaces=" ">
        <sectiontitle>
          Input encodings
        </sectiontitle>
        <cindex index="cp" spaces=" ">
          <indexterm index="cp" number="50">
            character encoding
          </indexterm>
        </cindex>
        <cindex index="cp" spaces=" ">
          <indexterm index="cp" number="51">
            input encodings
          </indexterm>
        </cindex>
        <cindex index="cp" spaces=" ">
          <indexterm index="cp" number="52">
            encodings, input
          </indexterm>
        </cindex>
        <para>
          The input to
Default handler: &tex;
           (or any computer program) ultimately consists of a sequence of bytes. (Nowadays, a byte is almost universally an eight-bit number, i.e., an integer between 0 and 255, inclusive.) The input encoding defines how to interpret that sequence of bytes, and thus how
Default handler: &latex;
           behaves.
        </para>
Default handler: <!-- c UTF-8 -->
        <cindex index="cp" spaces=" ">
          <indexterm index="cp" number="53">
            Unicode
          </indexterm>
        </cindex>
        <para>
          Today, by far the most common way to encode text is with
          <dfn>
            UTF-8
          </dfn>
          , a so-called
Default handler: &textldquo;
          Unicode Transformation Format
Default handler: &textrdquo;
           which specifies how to transform a sequence of 8-bit bytes to Unicode code points, which are defined independent of any particular representation. The Unicode encoding defines code points for virtually all characters used today in written text.
        </para>
        <para>
          When
Default handler: &tex;
           was created, Unicode and UTF-8 did not exist and the 7-bit ASCII encoding was by far the most widely used. So
Default handler: &tex;
           does not require Unicode for text input. UTF-8 is a superset of ASCII, so a pure 7-bit ASCII document is also UTF-8.
        </para>
        <para>
          Since 2018, the default input encoding for
Default handler: &latex;
           is UTF-8. Some methods for handling documents written in some other encoding, such as ISO-8859-1 (Latin 1), are explained in
          <ref label="inputenc-package">
            <xrefnodename>
              inputenc package
            </xrefnodename>
          </ref>
          .
        </para>
        <para>
          You can easily find more about all these topics in any introductory computer text or online. For example, you might start at:
          <url>
            <urefurl>
              https://en.wikipedia.org/wiki/Unicode
            </urefurl>
          </url>
          .
        </para>
      </subsection>
      <node name="Ligatures" spaces=" ">
        <nodename>
          Ligatures
        </nodename>
        <nodenext automatic="on">
          Special characters
        </nodenext>
        <nodeprev automatic="on">
          Input encodings
        </nodeprev>
        <nodeup automatic="on">
          Input text
        </nodeup>
      </node>
      <subsection spaces=" ">
        <sectiontitle>
          Ligatures
        </sectiontitle>
        <cindex index="cp" spaces=" ">
          <indexterm index="cp" number="54">
            ligatures
          </indexterm>
        </cindex>
        <para>
          A
          <dfn>
            ligature
          </dfn>
           combines two or more letters (more generally, characters) into a single glyph. For example, in Latin-based typography, the two letters
          <samp>
            f
          </samp>
           and
          <samp>
            i
          </samp>
           are often combined into the glyph
Default handler: &textlsquo;
          fi
Default handler: &textrsquo;
          .
        </para>
        <paraDefault handler: &tex;
>
           supports ligatures automatically. To continue the example, if the input has the word
          <samp>
            fine
          </samp>
          , written as four separate ASCII characters,
Default handler: &tex;
           will output the word
Default handler: &textlsquo;
          fine
Default handler: &textrsquo;
           (with the default fonts), with three typeset glyphs.
        </para>
        <para>
          In traditional
Default handler: &tex;
          , the available ligatures, if any, are defined by the current font.
Default handler: &tex;
           also uses the ligature mechanism to produce a few typographical characters which were not available in any computer encoding when
Default handler: &tex;
           was invented. In all, in the original Computer Modern fonts, the following input character sequences are defined to lead to ligatures:
        </para>
        <cindex index="cp" spaces=" ">
          <indexterm index="cp" number="55">
            f-ligatures
          </indexterm>
        </cindex>
        <cindex index="cp" spaces=" ">
          <indexterm index="cp" number="56">
            double quotation marks, as ligatures
          </indexterm>
        </cindex>
        <cindex index="cp" spaces=" ">
          <indexterm index="cp" number="57">
            quotation marks, as ligatures
          </indexterm>
        </cindex>
        <cindex index="cp" spaces=" ">
          <indexterm index="cp" number="58">
            en-dash, as ligature
          </indexterm>
        </cindex>
        <cindex index="cp" spaces=" ">
          <indexterm index="cp" number="59">
            em-dash, as ligature
          </indexterm>
        </cindex>
        <cindex index="cp" spaces=" ">
          <indexterm index="cp" number="60">
            inverted exclamation mark, as ligature
          </indexterm>
        </cindex>
        <cindex index="cp" spaces=" ">
          <indexterm index="cp" number="61">
            inverted question mark, as ligature
          </indexterm>
        </cindex>
        <cindex index="cp" spaces=" ">
          <indexterm index="cp" number="62">
            Spanish exclamation mark, as ligature
          </indexterm>
        </cindex>
        <cindex index="cp" spaces=" ">
          <indexterm index="cp" number="63">
            Spanish question mark, as ligature
          </indexterm>
        </cindex>
        <table commandarg="samp" spaces=" " endspaces=" ">
          <tableentry>
            <tableterm>
              <item spaces=" ">
                <itemformat command="samp">
                  ff
                </itemformat>
              </item>
            </tableterm>
            <tableitem>
              <para>
                ff (f
                <r/>
                f ligature, U+FB00)
              </para>
            </tableitem>
          </tableentry>
          <tableentry>
            <tableterm>
              <item spaces=" ">
                <itemformat command="samp">
                  fi
                </itemformat>
              </item>
            </tableterm>
            <tableitem>
              <para>
                fi (f
                <r/>
                i ligature, U+FB01)
              </para>
            </tableitem>
          </tableentry>
          <tableentry>
            <tableterm>
              <item spaces=" ">
                <itemformat command="samp">
                  fl
                </itemformat>
              </item>
            </tableterm>
            <tableitem>
              <para>
                fl (f
                <r/>
                l ligature, U+FB02)
              </para>
            </tableitem>
          </tableentry>
          <tableentry>
            <tableterm>
              <item spaces=" ">
                <itemformat command="samp">
                  ffi
                </itemformat>
              </item>
            </tableterm>
            <tableitem>
              <para>
                ffi (f
                <r/>
                f
                <r/>
                i ligature, U+FB03)
              </para>
            </tableitem>
          </tableentry>
          <tableentry>
            <tableterm>
              <item spaces=" ">
                <itemformat command="samp">
                  ffl
                </itemformat>
              </item>
            </tableterm>
            <tableitem>
              <para>
                ffl (f
                <r/>
                f
                <r/>
                l ligature, U+FB04)
              </para>
            </tableitem>
          </tableentry>
          <tableentry>
            <tableterm>
              <item spaces=" ">
                <itemformat command="samp">
                  ``
                </itemformat>
              </item>
            </tableterm>
            <tableitem>
              <paraDefault handler: &textldquo;
>
                 (left double quotation mark, U+201C)
              </para>
            </tableitem>
          </tableentry>
          <tableentry>
            <tableterm>
              <item spaces=" ">
                <itemformat command="samp">
                  ''
                </itemformat>
              </item>
            </tableterm>
            <tableitem>
              <paraDefault handler: &textrdquo;
>
                 (right double quotation mark, U+201D)
              </para>
            </tableitem>
          </tableentry>
          <tableentry>
            <tableterm>
              <item spaces=" ">
                <itemformat command="samp">
                  --
                </itemformat>
              </item>
            </tableterm>
            <tableitem>
              <paraDefault handler: &textndash;
>
                 (en-dash, U+2013)
              </para>
            </tableitem>
          </tableentry>
          <tableentry>
            <tableterm>
              <item spaces=" ">
                <itemformat command="samp">
                  ---
                </itemformat>
              </item>
            </tableterm>
            <tableitem>
              <paraDefault handler: &textmdash;
>
                 (em-dash, U+2014)
              </para>
            </tableitem>
          </tableentry>
          <tableentry>
            <tableterm>
              <item spaces=" ">
                <itemformat command="samp">
                  !`
                </itemformat>
              </item>
            </tableterm>
            <tableitem>
              <para>
                !
Default handler: &textlsquo;
                 (inverted exclamation mark, U+00A1)
              </para>
            </tableitem>
          </tableentry>
          <tableentry>
            <tableterm>
              <item spaces=" ">
                <itemformat command="samp">
                  ?`
                </itemformat>
              </item>
            </tableterm>
            <tableitem>
              <para>
                ?
Default handler: &textlsquo;
                 (inverted question mark, U+00BF)
              </para>
            </tableitem>
          </tableentry>
        </table>
        <noindent/>
        <para>
          (For the f-ligatures above, the text in parentheses shows the individual characters, so in the typeset output you can easily see the difference between the ligature and the original character sequence.)
        </para>
        <para>
          Nowadays it
Default handler: &textrsquo;
          s usually possible to directly input the punctuation characters as Unicode characters, and
Default handler: &latex;
           supports that (see previous section). But even today, it can still often be useful to use the ASCII ligature input form; for example, the difference between an en-dash and em-dash, as a single glyph, can be all but impossible to discern, but the difference between two and three ASCII hyphen characters is clear. Similarly with quotation marks, in some fonts.
        </para>
        <para>
          Thus, even the engines with native support for UTF-8, namely Lua
Default handler: &tex;
           and Xe
Default handler: &tex;
          , also support the ASCII ligature input sequences by default, independent of the font used. They also need to do so for compatibility.
        </para>
        <cindex index="cp" spaces=" ">
          <indexterm index="cp" number="64">
            alphabetic presentation forms Unicode block
          </indexterm>
        </cindex>
        <para>
          By the way, the f-ligatures are also available in Unicode (the
Default handler: &textldquo;
          Alphabetic Presentation Forms
Default handler: &textrdquo;
           block starting at U+FB00), but it
Default handler: &textrsquo;
          s almost never desirable to use them as input characters, since in principle it should be up to the typesetter and the current font whether to use ligatures. Also, in practice, using them will typically cause searches to fail, that is, a search for the two characters
          <samp>
            fi
          </samp>
           will not be matched by the ligature
Default handler: &textlsquo;
          fi
Default handler: &textrsquo;
           at U+FB01.
        </para>
      </subsection>
      <node name="Special-characters" spaces=" ">
        <nodename>
          Special characters
        </nodename>
        <nodeprev automatic="on">
          Ligatures
        </nodeprev>
        <nodeup automatic="on">
          Input text
        </nodeup>
      </node>
      <subsection spaces=" ">
        <sectiontitle>
          Special characters:
          <code>
            \
Default handler: &lbrace;
Default handler: &rbrace;
             % $
            &
             _ ^ # ~
          </code>
        </sectiontitle>
        <anchor name="Reserved-characters">
          Reserved characters
        </anchor>
Default handler: <!-- c old node name -->
        <cindex index="cp" spaces=" ">
          <indexterm index="cp" number="65">
            reserved characters, meaning of
          </indexterm>
        </cindex>
        <cindex index="cp" spaces=" ">
          <indexterm index="cp" number="66">
            special characters, meaning of
          </indexterm>
        </cindex>
        <cindex index="cp" spaces=" ">
          <indexterm index="cp" number="67">
            meaning of special characters
          </indexterm>
        </cindex>
        <para>
          Besides ligatures (see previous section), a few individual characters have special meaning to
Default handler: &latex;
          . They are called
          <dfn>
            reserved characters
          </dfn>
           or
          <dfn>
            special characters
          </dfn>
          . Here they are:
        </para>
        <table commandarg="samp" spaces=" " endspaces=" ">
          <tableentry>
            <tableterm>
              <item spaces=" ">
                <itemformat command="samp">
                  \
                </itemformat>
              </item>
            </tableterm>
            <tableitem>
              <findex index="fn" spaces=" ">
                <indexterm index="fn" number="36" mergedindex="cp">
                  \
                  <r>
                    character
                  </r>
                  , meaning of
                </indexterm>
              </findex>
              <cindex index="cp" spaces=" ">
                <indexterm index="cp" number="68">
                  backslash, meaning of
                </indexterm>
              </cindex>
              <para>
                Introduces a command name, as seen throughout this manual.
              </para>
            </tableitem>
          </tableentry>
          <tableentry>
            <tableterm>
              <item spaces=" ">
                <itemformat command="samp"Default handler: &lbrace;
/>
              </item>
              <itemx spaces=" ">
                <itemformat command="samp"Default handler: &rbrace;
/>
              </itemx>
            </tableterm>
            <tableitem>
              <findex index="fn" spaces=" ">
                <indexterm index="fn" number="37" mergedindex="cp"Default handler: &lbrace;
>
                  <r>
                    character
                  </r>
                  , meaning of
                </indexterm>
              </findex>
              <findex index="fn" spaces=" ">
                <indexterm index="fn" number="38" mergedindex="cp"Default handler: &rbrace;
>
                  <r>
                    character
                  </r>
                  , meaning of
                </indexterm>
              </findex>
              <cindex index="cp" spaces=" ">
                <indexterm index="cp" number="69">
                  left brace, meaning of
                </indexterm>
              </cindex>
              <cindex index="cp" spaces=" ">
                <indexterm index="cp" number="70">
                  right brace, meaning of
                </indexterm>
              </cindex>
              <cindex index="cp" spaces=" ">
                <indexterm index="cp" number="71">
                  braces, meaning of
                </indexterm>
              </cindex>
              <cindex index="cp" spaces=" ">
                <indexterm index="cp" number="72">
                  curly braces, meaning of
                </indexterm>
              </cindex>
              <para>
                Delimits a required argument to a command or a level of grouping, as seen throughout this manual.
              </para>
            </tableitem>
          </tableentry>
          <tableentry>
            <tableterm>
              <item spaces=" ">
                <itemformat command="samp">
                  %
                </itemformat>
              </item>
            </tableterm>
            <tableitem>
              <findex index="fn" spaces=" ">
                <indexterm index="fn" number="39" mergedindex="cp">
                  %
                  <r>
                    character
                  </r>
                  , meaning of
                </indexterm>
              </findex>
              <cindex index="cp" spaces=" ">
                <indexterm index="cp" number="73">
                  percent character, meaning of
                </indexterm>
              </cindex>
              <para>
                Starts a comment: the
                <samp>
                  %
                </samp>
                 and all remaining characters on the current line are ignored.
              </para>
            </tableitem>
          </tableentry>
          <tableentry>
            <tableterm>
              <item spaces=" ">
                <itemformat command="samp">
                  $
                </itemformat>
              </item>
            </tableterm>
            <tableitem>
              <findex index="fn" spaces=" ">
                <indexterm index="fn" number="40" mergedindex="cp">
                  $
                  <r>
                    character
                  </r>
                  , meaning of
                </indexterm>
              </findex>
              <cindex index="cp" spaces=" ">
                <indexterm index="cp" number="74">
                  dollar sign character, meaning of
                </indexterm>
              </cindex>
              <para>
                Starts and ends math mode (
                <pxref label="Math-formulas">
                  <xrefnodename>
                    Math formulas
                  </xrefnodename>
                </pxref>
                ).
              </para>
            </tableitem>
          </tableentry>
          <tableentry>
            <tableterm>
              <item spaces=" ">
                <itemformat command="samp">
                  &
                </itemformat>
              </item>
            </tableterm>
            <tableitem>
              <findex index="fn" spaces=" ">
                <indexterm index="fn" number="41" mergedindex="cp">
                  &
                  <r>
                    character
                  </r>
                  , meaning of
                </indexterm>
              </findex>
              <cindex index="cp" spaces=" ">
                <indexterm index="cp" number="75">
                  ampersand character, meaning of
                </indexterm>
              </cindex>
              <para>
                Separates cells in a table (
                <pxref label="tabular">
                  <xrefnodename>
                    tabular
                  </xrefnodename>
                </pxref>
                ).
              </para>
            </tableitem>
          </tableentry>
          <tableentry>
            <tableterm>
              <item spaces=" ">
                <itemformat command="samp">
                  _
                </itemformat>
              </item>
              <itemx spaces=" ">
                <itemformat command="samp">
                  ^
                </itemformat>
              </itemx>
            </tableterm>
            <tableitem>
              <findex index="fn" spaces=" ">
                <indexterm index="fn" number="42" mergedindex="cp">
                  _
                  <r>
                    character
                  </r>
                  , meaning of
                </indexterm>
              </findex>
              <findex index="fn" spaces=" ">
                <indexterm index="fn" number="43" mergedindex="cp">
                  ^
                  <r>
                    character
                  </r>
                  , meaning of
                </indexterm>
              </findex>
              <cindex index="cp" spaces=" ">
                <indexterm index="cp" number="76">
                  underscore character, meaning of
                </indexterm>
              </cindex>
              <cindex index="cp" spaces=" ">
                <indexterm index="cp" number="77">
                  hat character, meaning of
                </indexterm>
              </cindex>
              <cindex index="cp" spaces=" ">
                <indexterm index="cp" number="78">
                  caret character, meaning of
                </indexterm>
              </cindex>
              <para>
                Introduce a subscript or superscript, respectively, in math (
                <pxref label="Subscripts-_0026-superscripts">
                  <xrefnodename>
                    Subscripts
                    &
                     superscripts
                  </xrefnodename>
                </pxref>
                ); they produce an error outside math mode. As a little-used special feature, two superscript characters in a row can introduce special notation for an arbitrary character.
              </para>
            </tableitem>
          </tableentry>
          <tableentry>
            <tableterm>
              <item spaces=" ">
                <itemformat command="samp">
                  #
                </itemformat>
              </item>
            </tableterm>
            <tableitem>
              <findex index="fn" spaces=" ">
                <indexterm index="fn" number="44" mergedindex="cp">
                  #
                  <r>
                    character
                  </r>
                  , meaning of
                </indexterm>
              </findex>
              <cindex index="cp" spaces=" ">
                <indexterm index="cp" number="79">
                  number sign character (
                  <code>
                    #
                  </code>
                  ), meaning of
                </indexterm>
              </cindex>
              <cindex index="cp" spaces=" ">
                <indexterm index="cp" number="80">
                  sharp character (
                  <code>
                    #
                  </code>
                  ), meaning of
                </indexterm>
              </cindex>
              <cindex index="cp" spaces=" ">
                <indexterm index="cp" number="81">
                  hash character (
                  <code>
                    #
                  </code>
                  ), meaning of
                </indexterm>
              </cindex>
              <para>
                Stands for arguments in a macro definition (
                <pxref label="_005cnewcommand-_0026-_005crenewcommand">
                  <xrefnodename>
                    \newcommand
                    &
                     \renewcommand
                  </xrefnodename>
                </pxref>
                ).
              </para>
            </tableitem>
          </tableentry>
          <tableentry>
            <tableterm>
              <item spaces=" ">
                <itemformat command="samp">
                  ~
                </itemformat>
              </item>
            </tableterm>
            <tableitem>
              <findex index="fn" spaces=" ">
                <indexterm index="fn" number="45" mergedindex="cp">
                  ~
                  <r>
                    character
                  </r>
                  , meaning of
                </indexterm>
              </findex>
              <cindex index="cp" spaces=" ">
                <indexterm index="cp" number="82">
                  tilde character, meaning of
                </indexterm>
              </cindex>
              <para>
                Produces a nonbreakable interword space (
                <pxref label="_007e">
                  <xrefnodename>
                    ~
                  </xrefnodename>
                </pxref>
                ).
              </para>
            </tableitem>
          </tableentry>
        </table>
        <para>
          <xref label="Printing-special-characters">
            <xrefnodename>
              Printing special characters
            </xrefnodename>
          </xref>
          , for how to typeset these characters when you need them literally.
        </para>
      </subsection>
    </section>
    <node name="LaTeX-command-syntax" spaces=" ">
      <nodenameDefault handler: &latex;
>
         command syntax
      </nodename>
      <nodenext automatic="on">
        Environment syntax
      </nodenext>
      <nodeprev automatic="on">
        Input text
      </nodeprev>
      <nodeup automatic="on">
        Overview
      </nodeup>
    </node>
    <section spaces=" ">
      <sectiontitleDefault handler: &latex;
>
         command syntax
      </sectiontitle>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="83">
          command syntax
        </indexterm>
      </cindex>
      <findex index="fn" spaces=" ">
        <indexterm index="fn" number="46" mergedindex="cp">
          \
          <r>
            character starting commands
          </r>
        </indexterm>
      </findex>
      <findex index="fn" spaces=" ">
        <indexterm index="fn" number="47" mergedindex="cp">
          [...]
          <r>
            (for optional arguments)
          </r>
        </indexterm>
      </findex>
      <findex index="fn" spaces=" ">
        <indexterm index="fn" number="48" mergedindex="cp"Default handler: &lbrace;
>
          ...
Default handler: &rbrace;
          <r>
            (for required arguments)
          </r>
        </indexterm>
      </findex>
      <para>
        In the
Default handler: &latex;
         input file, a command name starts with a backslash character,
        <code>
          \
        </code>
        . The name itself then consists of either (a)
Default handler: &nbsp;
        a string of letters or (b)
Default handler: &nbsp;
        a single non-letter.
      </para>
      <paraDefault handler: &latex;
>
         commands names are case sensitive; for example,
        <code>
          \pagebreak
        </code>
         differs from
        <code>
          \Pagebreak
        </code>
         (the latter is not a standard command). Most command names are lowercase, but in any event you must enter all commands in the same case as they are defined.
      </para>
      <para>
        A command may be followed by zero, one, or more arguments. These arguments may be either required or optional. Required arguments are contained in curly braces,
        <codeDefault handler: &lbrace;
>
          ...
Default handler: &rbrace;
        </code>
        . Optional arguments are contained in square brackets,
        <code>
          [...]
        </code>
        . Generally, but not universally, if the command accepts an optional argument, it comes first, before any required arguments; optional arguments could come after required arguments, or both before and after.
      </para>
      <para>
        Inside of an optional argument, to use the character close square bracket
Default handler: &nbsp;
        (
        <code>
          ]
        </code>
        ) hide it inside curly braces, as in
Default handler: &nbsp;
        <code>
          \item[closing bracket
Default handler: &lbrace;
          ]
Default handler: &rbrace;
          ]
        </code>
        . Similarly, if an optional argument comes last, with no required argument after it, then to make the first character of the following text be an open square bracket, hide it inside curly braces.
      </para>
      <paraDefault handler: &latex;
>
         has the convention that some commands have a
        <code>
          *
        </code>
         form that is closely related to the form without a
        <code>
          *
        </code>
        , such as
        <code>
          \chapter
        </code>
         and
        <code>
          \chapter*
        </code>
        . The difference in behavior varies from command to command.
      </para>
      <para>
        This manual describes all accepted options and
        <code>
          *
        </code>
        -forms for the commands it covers (barring unintentional omissions, a.k.a.
Default handler: &noeos;
         bugs).
      </para>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="84">
          <r>
            package
          </r>
          ,
          <code>
            expl3
          </code>
        </indexterm>
      </cindex>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="85">
          <code>
            expl3
          </code>
          <r>
            package
          </r>
        </indexterm>
      </cindex>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="86">
          <r>
            package
          </r>
          ,
          <code>
            xparse
          </code>
        </indexterm>
      </cindex>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="87">
          <code>
            xparse
          </code>
          <r>
            package
          </r>
        </indexterm>
      </cindex>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="88"Default handler: &latex;
>
          3 syntax
        </indexterm>
      </cindex>
      <para>
        As of the 2020-10-01 release of
Default handler: &latex;
        , the
        <code>
          expl3
        </code>
         and
        <code>
          xparse
        </code>
         packages are part of the
Default handler: &latex;
        2e format. They provide a completely different underlying programming language syntax. We won
Default handler: &textrsquo;
        t try to cover that in this document; see the related package documentation and other
Default handler: &latex;
         manuals.
      </para>
    </section>
    <node name="Environment-syntax" spaces=" ">
      <nodename>
        Environment syntax
      </nodename>
      <nodenext automatic="on">
        \DocumentMetadata
      </nodenext>
      <nodeprev automatic="on"Default handler: &latex;
>
         command syntax
      </nodeprev>
      <nodeup automatic="on">
        Overview
      </nodeup>
    </node>
    <section spaces=" ">
      <sectiontitle>
        Environment syntax
      </sectiontitle>
      <para>
        Synopsis:
      </para>
      <example endspaces=" ">
        <pre xml:space="preserve">
          \begin
Default handler: &lbrace;
          <var>
            environment-name
          </var>
Default handler: &rbrace;
           ... \end
Default handler: &lbrace;
          <var>
            environment-name
          </var>
Default handler: &rbrace;
        </pre>
      </example>
      <para>
        An
        <dfn>
          environment
        </dfn>
         is an area of
Default handler: &latex;
         source, inside of which there is a distinct behavior. For instance, for poetry in
Default handler: &latex;
         put the lines between
        <code>
          \begin
Default handler: &lbrace;
          verse
Default handler: &rbrace;
        </code>
         and
        <code>
          \end
Default handler: &lbrace;
          verse
Default handler: &rbrace;
        </code>
        .
      </para>
      <example endspaces=" ">
        <pre xml:space="preserve">
          \begin
Default handler: &lbrace;
          verse
Default handler: &rbrace;
           There once was a man from Nantucket \\ ... \end
Default handler: &lbrace;
          verse
Default handler: &rbrace;
        </pre>
      </example>
      <para>
        <xref label="Environments">
          <xrefnodename>
            Environments
          </xrefnodename>
        </xref>
        , for a list of environments. Particularly notable is that every
Default handler: &latex;
         document must have a
        <code>
          document
        </code>
         environment, a
        <code>
          \begin
Default handler: &lbrace;
          document
Default handler: &rbrace;
           ... \end
Default handler: &lbrace;
          document
Default handler: &rbrace;
        </code>
         pair.
      </para>
      <para>
        The
        <var>
          environment-name
        </var>
         at the beginning must exactly match that at the end. This includes the case where
        <var>
          environment-name
        </var>
         ends in a star
Default handler: &nbsp;
        (
        <code>
          *
        </code>
        ); both the
        <code>
          \begin
        </code>
         and
        <code>
          \end
        </code>
         texts must include the star.
      </para>
      <para>
        Environments may have arguments, including optional arguments. This example produces a table. The first argument is optional (and causes the table to be aligned on its top row) while the second argument is required (it specifies the formatting of columns).
      </para>
      <example endspaces=" ">
        <pre xml:space="preserve">
          \begin
Default handler: &lbrace;
          tabular
Default handler: &rbrace;
          [t]
Default handler: &lbrace;
          r|l
Default handler: &rbrace;
           ...
          <var>
            rows-of-table
          </var>
           ... \end
Default handler: &lbrace;
          tabular
Default handler: &rbrace;
        </pre>
      </example>
    </section>
    <node name="_005cDocumentMetadata" spaces=" ">
      <nodename>
        \DocumentMetadata
      </nodename>
      <nodenext automatic="on">
        CTAN
      </nodenext>
      <nodeprev automatic="on">
        Environment syntax
      </nodeprev>
      <nodeup automatic="on">
        Overview
      </nodeup>
    </node>
    <section spaces=" ">
      <sectiontitle>
        <code>
          \DocumentMetadata
        </code>
        : Producing tagged PDF output
      </sectiontitle>
      <findex index="fn" spaces=" ">
        <indexterm index="fn" number="49" mergedindex="cp">
          \DocumentMetadata
        </indexterm>
      </findex>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="89">
          tagged PDF
        </indexterm>
      </cindex>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="90">
          PDF, tagged
        </indexterm>
      </cindex>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="91">
          metadata, adding
        </indexterm>
      </cindex>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="92">
          accessibility
        </indexterm>
      </cindex>
      <para>
        The
        <code>
          \DocumentMetadata
        </code>
         command was added to
Default handler: &latex;
         in 2022. It enables so-called
Default handler: &textldquo;
        tagging
Default handler: &textrdquo;
         of the PDF output, aiding accessibility of the PDF. It is supported best with Lua
Default handler: &latex;
        ; pdf
Default handler: &latex;
         and Xe
Default handler: &latex;
         are supported as well as possible (
        <pxref label="TeX-engines">
          <xrefnodenameDefault handler: &tex;
>
             engines
          </xrefnodename>
        </pxref>
        ).
      </para>
      <para>
        It is unlike nearly any other command in
Default handler: &latex;
         in that it must occur before the
        <code>
          \documentclass
        </code>
         command that starts a
Default handler: &latex;
         document proper (
        <pxref label="_005cdocumentclass">
          <xrefnodename>
            \documentclass
          </xrefnodename>
        </pxref>
        ). Therefore it must be called with
        <code>
          \RequirePackage
        </code>
         rather than
        <code>
          \usepackage
        </code>
         (
        <pxref label="_005cRequirePackage">
          <xrefnodename>
            \RequirePackage
          </xrefnodename>
        </pxref>
        ).
      </para>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="93">
          <r>
            package
          </r>
          ,
          <code>
            latex-lab
          </code>
        </indexterm>
      </cindex>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="94">
          <code>
            latex-lab
          </code>
          <r>
            package
          </r>
        </indexterm>
      </cindex>
      <findex index="fn" spaces=" ">
        <indexterm index="fn" number="50" mergedindex="cp">
          documentmetadata-support-doc
          <r>
            document
          </r>
        </indexterm>
      </findex>
      <para>
        This support is still in development, so we will not try to list all the possible settings. Please see the
        <code>
          documentmetadata-support-doc
        </code>
         document, part of the
        <code>
          latex-lab
        </code>
         package (
        <url>
          <urefurl>
            https://ctan.org/pkg/latex-lab
          </urefurl>
        </url>
        ). Here is a simple example which enables most tagging currently implemented:
      </para>
      <example endspaces=" ">
        <pre xml:space="preserve">
          \DocumentMetadata
Default handler: &lbrace;
          testphase=
Default handler: &lbrace;
          phase-III,firstaid
Default handler: &rbrace;
Default handler: &rbrace;
           \documentclass
Default handler: &lbrace;
          article
Default handler: &rbrace;
           ...
        </pre>
      </example>
      <para>
        As you can see from the key name
        <code>
          testphase
        </code>
        , this is all still in an experimental phase. The
Default handler: &latex;
         developers strongly encourage users to give it a try and report problems, so it can be improved.
      </para>
    </section>
    <node name="CTAN" spaces=" ">
      <nodename>
        CTAN
      </nodename>
      <nodeprev automatic="on">
        \DocumentMetadata
      </nodeprev>
      <nodeup automatic="on">
        Overview
      </nodeup>
    </node>
    <section spaces=" ">
      <sectiontitle>
        CTAN: The Comprehensive
Default handler: &tex;
         Archive Network
      </sectiontitle>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="95">
          CTAN
        </indexterm>
      </cindex>
      <para>
        The Comprehensive
Default handler: &tex;
         Archive Network, CTAN, is the
Default handler: &tex;
         and
Default handler: &latex;
         community
Default handler: &textrsquo;
        s repository of free material. It is a set of Internet sites around the world that offer material related to
Default handler: &latex;
         for download. Visit CTAN on the web at
        <url>
          <urefurl>
            https://ctan.org
          </urefurl>
        </url>
        .
      </para>
      <para>
        This material is organized into packages, discrete bundles that typically offer some coherent functionality and are maintained by one person or a small number of people. For instance, many publishers have a package that allows authors to format papers to that publisher
Default handler: &textrsquo;
        s specifications.
      </para>
      <para>
        In addition to its massive holdings, the
        <code>
          ctan.org
        </code>
         web site offers features such as search by name or by functionality.
      </para>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="96">
          DANTE e.V.
        </indexterm>
      </cindex>
      <para>
        CTAN is not a single host, but instead is a set of hosts, one of which is the so-called
Default handler: &textldquo;
        master
Default handler: &textrdquo;
        . The master host actively manages the material, for instance, by accepting uploads of new or updated packages. For many years, it has been hosted by the German
Default handler: &tex;
         group, DANTE e.V.
      </para>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="97">
          mirrors of CTAN
        </indexterm>
      </cindex>
      <para>
        Other sites around the world help out by mirroring, that is, automatically syncing their collections with the master site and then in turn making their copies publicly available. This gives users close to their location better access and relieves the load on the master site. The list of mirrors is at
        <url>
          <urefurl>
            https://ctan.org/mirrors
          </urefurl>
        </url>
        .
      </para>
    </section>
  </chapter>
  <node name="Document-classes" spaces=" ">
    <nodename>
      Document classes
    </nodename>
    <nodenext automatic="on">
      Fonts
    </nodenext>
    <nodeprev automatic="on">
      Overview
    </nodeprev>
    <nodeup automatic="on">
      Top
    </nodeup>
  </node>
  <chapter spaces=" ">
    <sectiontitle>
      Document classes
    </sectiontitle>
    <anchor name="_005cdocumentclass">
      \documentclass
    </anchor>
    <cindex index="cp" spaces=" ">
      <indexterm index="cp" number="98">
        document classes
      </indexterm>
    </cindex>
    <cindex index="cp" spaces=" ">
      <indexterm index="cp" number="99">
        classes of documents
      </indexterm>
    </cindex>
    <findex index="fn" spaces=" ">
      <indexterm index="fn" number="51" mergedindex="cp">
        \documentclass
      </indexterm>
    </findex>
    <para>
      The document
Default handler: &textrsquo;
      s overall class is defined with the
      <code>
        \documentclass
      </code>
       command, which is normally the first command in a
Default handler: &latex;
       source file.
    </para>
    <example endspaces=" ">
      <pre xml:space="preserve">
        \documentclass[
        <var>
          options
        </var>
        ]
Default handler: &lbrace;
        <var>
          class
        </var>
Default handler: &rbrace;
      </pre>
    </example>
    <findex index="fn" spaces=" ">
      <indexterm index="fn" number="52" mergedindex="cp">
        article
        <r>
          class
        </r>
      </indexterm>
    </findex>
    <findex index="fn" spaces=" ">
      <indexterm index="fn" number="53" mergedindex="cp">
        report
        <r>
          class
        </r>
      </indexterm>
    </findex>
    <findex index="fn" spaces=" ">
      <indexterm index="fn" number="54" mergedindex="cp">
        book
        <r>
          class
        </r>
      </indexterm>
    </findex>
    <findex index="fn" spaces=" ">
      <indexterm index="fn" number="55" mergedindex="cp">
        letter
        <r>
          class
        </r>
      </indexterm>
    </findex>
    <findex index="fn" spaces=" ">
      <indexterm index="fn" number="56" mergedindex="cp">
        slides
        <r>
          class
        </r>
      </indexterm>
    </findex>
    <para>
      The following document
      <var>
        class
      </var>
       names are built into
Default handler: &latex;
      . Many other document classes are available as separate packages (
      <pxref label="Overview">
        <xrefnodename>
          Overview
        </xrefnodename>
      </pxref>
      ).
    </para>
    <table commandarg="code" spaces=" " endspaces=" ">
      <tableentry>
        <tableterm>
          <item spaces=" ">
            <itemformat command="code">
              article
            </itemformat>
          </item>
        </tableterm>
        <tableitem>
          <anchor name="document-classes-article">
            document classes article
          </anchor>
          <para>
            For a journal article, a presentation, and miscellaneous general use.
          </para>
        </tableitem>
      </tableentry>
      <tableentry>
        <tableterm>
          <item spaces=" ">
            <itemformat command="code">
              book
            </itemformat>
          </item>
        </tableterm>
        <tableitem>
          <anchor name="document-classes-book">
            document classes book
          </anchor>
          <para>
            Full-length books, including chapters and possibly including front matter, such as a preface, and back matter, such as an appendix (
            <pxref label="Front_002fback-matter">
              <xrefnodename>
                Front/back matter
              </xrefnodename>
            </pxref>
            ).
          </para>
        </tableitem>
      </tableentry>
      <tableentry>
        <tableterm>
          <item spaces=" ">
            <itemformat command="code">
              letter
            </itemformat>
          </item>
        </tableterm>
        <tableitem>
          <anchor name="document-classes-letter">
            document classes letter
          </anchor>
          <para>
            Mail, optionally including mailing labels (
            <pxref label="Letters">
              <xrefnodename>
                Letters
              </xrefnodename>
            </pxref>
            ).
          </para>
        </tableitem>
      </tableentry>
      <tableentry>
        <tableterm>
          <item spaces=" ">
            <itemformat command="code">
              report
            </itemformat>
          </item>
        </tableterm>
        <tableitem>
          <anchor name="document-classes-report">
            document classes report
          </anchor>
          <para>
            For documents of length between an
            <code>
              article
            </code>
             and a
            <code>
              book
            </code>
            , such as technical reports or theses, which may contain several chapters.
          </para>
        </tableitem>
      </tableentry>
      <tableentry>
        <tableterm>
          <item spaces=" ">
            <itemformat command="code">
              slides
            </itemformat>
          </item>
        </tableterm>
        <tableitem>
          <anchor name="document-classes-slides">
            document classes slides
          </anchor>
          <para>
            For slide presentations
Default handler: &textmdash;
            rarely used nowadays. The
            <code>
              beamer
            </code>
             package is perhaps the most prevalent replacement (
            <url>
              <urefurl>
                https://ctan.org/pkg/beamer
              </urefurl>
            </url>
            ).
            <xref label="beamer-template">
              <xrefnodename>
                beamer template
              </xrefnodename>
            </xref>
            , for a small template for a beamer document.
          </para>
        </tableitem>
      </tableentry>
    </table>
    <para>
      Standard
      <var>
        options
      </var>
       are described in the next section.
    </para>
    <menu endspaces=" ">
      <menuentry>
        <menuleadingtext>
          *
        </menuleadingtext>
        <menunode>
          Document class options
        </menunode>
        <menuseparator>
          ::
        </menuseparator>
        <menudescription>
          <pre xml:space="preserve">
            Global options.
          </pre>
        </menudescription>
      </menuentry>
      <menuentry>
        <menuleadingtext>
          *
        </menuleadingtext>
        <menunode>
          \usepackage
        </menunode>
        <menuseparator>
          ::
        </menuseparator>
        <menudescription>
          <pre xml:space="preserve">
            Bring in additional packages.
          </pre>
        </menudescription>
      </menuentry>
      <menuentry>
        <menuleadingtext>
          *
        </menuleadingtext>
        <menunode>
          Class and package creation
        </menunode>
        <menuseparator>
          ::
        </menuseparator>
        <menudescription>
          <pre xml:space="preserve">
            Writing new classes and packages.
          </pre>
        </menudescription>
      </menuentry>
    </menu>
    <node name="Document-class-options" spaces=" ">
      <nodename>
        Document class options
      </nodename>
      <nodenext automatic="on">
        \usepackage
      </nodenext>
      <nodeup automatic="on">
        Document classes
      </nodeup>
    </node>
    <section spaces=" ">
      <sectiontitle>
        Document class options
      </sectiontitle>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="100">
          document class options
        </indexterm>
      </cindex>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="101">
          options, document class
        </indexterm>
      </cindex>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="102">
          class options
        </indexterm>
      </cindex>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="103">
          global options
        </indexterm>
      </cindex>
      <para>
        You can specify
        <dfn>
          global options
        </dfn>
         or
        <dfn>
          class options
        </dfn>
         to the
        <code>
          \documentclass
        </code>
         command by enclosing them in square brackets. To specify more than one
        <var>
          option
        </var>
        , separate them with a comma.
      </para>
      <example endspaces=" ">
        <pre xml:space="preserve">
          \documentclass[
          <var>
            option1
          </var>
          ,
          <var>
            option2
          </var>
          ,...]
Default handler: &lbrace;
          <var>
            class
          </var>
Default handler: &rbrace;
        </pre>
      </example>
      <paraDefault handler: &latex;
>
         automatically passes options specified for
        <code>
          \documentclass
        </code>
         on to any other loaded classes that can handle them.
      </para>
      <para>
        Here is the list of the standard class options.
      </para>
      <findex index="fn" spaces=" ">
        <indexterm index="fn" number="57" mergedindex="cp">
          10pt
          <r>
            option
          </r>
        </indexterm>
      </findex>
      <findex index="fn" spaces=" ">
        <indexterm index="fn" number="58" mergedindex="cp">
          11pt
          <r>
            option
          </r>
        </indexterm>
      </findex>
      <findex index="fn" spaces=" ">
        <indexterm index="fn" number="59" mergedindex="cp">
          12pt
          <r>
            option
          </r>
        </indexterm>
      </findex>
      <para>
        All of the standard classes except
        <code>
          slides
        </code>
         accept the following options for selecting the typeface size; the default is
        <code>
          10pt
        </code>
        :
      </para>
      <example endspaces=" ">
        <pre xml:space="preserve">
          10pt 11pt 12pt
        </pre>
      </example>
      <findex index="fn" spaces=" ">
        <indexterm index="fn" number="60" mergedindex="cp">
          a4paper
          <r>
            option
          </r>
        </indexterm>
      </findex>
      <findex index="fn" spaces=" ">
        <indexterm index="fn" number="61" mergedindex="cp">
          a5paper
          <r>
            option
          </r>
        </indexterm>
      </findex>
      <findex index="fn" spaces=" ">
        <indexterm index="fn" number="62" mergedindex="cp">
          b5paper
          <r>
            option
          </r>
        </indexterm>
      </findex>
      <findex index="fn" spaces=" ">
        <indexterm index="fn" number="63" mergedindex="cp">
          executivepaper
          <r>
            option
          </r>
        </indexterm>
      </findex>
      <findex index="fn" spaces=" ">
        <indexterm index="fn" number="64" mergedindex="cp">
          legalpaper
          <r>
            option
          </r>
        </indexterm>
      </findex>
      <findex index="fn" spaces=" ">
        <indexterm index="fn" number="65" mergedindex="cp">
          letterpaper
          <r>
            option
          </r>
        </indexterm>
      </findex>
      <para>
        All of the standard classes accept these options for selecting the paper size (dimensions are listed height by width):
      </para>
      <table commandarg="code" spaces=" " endspaces=" ">
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                a4paper
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <para>
              210 by 297
              <dmn>
                mm
              </dmn>
               (about 8.25 by 11.75
Default handler: &nbsp;
              inches)
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                a5paper
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <para>
              148 by 210
              <dmn>
                mm
              </dmn>
               (about 5.8 by 8.3
Default handler: &nbsp;
              inches)
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                b5paper
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <para>
              176 by 250
              <dmn>
                mm
              </dmn>
               (about 6.9 by 9.8
Default handler: &nbsp;
              inches)
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                executivepaper
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <para>
              7.25 by 10.5
Default handler: &nbsp;
              inches
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                legalpaper
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <para>
              8.5 by 14
Default handler: &nbsp;
              inches
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                letterpaper
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <para>
              8.5 by 11
Default handler: &nbsp;
              inches (the default)
            </para>
          </tableitem>
        </tableentry>
      </table>
      <findex index="fn" spaces=" ">
        <indexterm index="fn" number="66" mergedindex="cp">
          \pdfpagewidth
        </indexterm>
      </findex>
      <findex index="fn" spaces=" ">
        <indexterm index="fn" number="67" mergedindex="cp">
          \pdfpageheight
        </indexterm>
      </findex>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="104">
          <r>
            package
          </r>
          ,
          <code>
            geometry
          </code>
        </indexterm>
      </cindex>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="105">
          <code>
            geometry
          </code>
          <r>
            package
          </r>
        </indexterm>
      </cindex>
      <para>
        When using one of the engines pdf
Default handler: &latex;
        , Lua
Default handler: &latex;
        , or Xe
Default handler: &latex;
         (
        <pxref label="TeX-engines">
          <xrefnodenameDefault handler: &tex;
>
             engines
          </xrefnodename>
        </pxref>
        ), options other than
        <code>
          letterpaper
        </code>
         set the print area but you must also set the physical paper size. Usually, the
        <code>
          geometry
        </code>
         package is the best way to do that; it provides flexible ways of setting the print area and physical page size. Otherwise, setting the paper size is engine-dependent. For example, with pdf
Default handler: &latex;
        , you could include
        <code>
          \pdfpagewidth=\paperwidth
        </code>
         and
        <code>
          \pdfpageheight=\paperheight
        </code>
         in the preamble.
      </para>
      <findex index="fn" spaces=" ">
        <indexterm index="fn" number="68" mergedindex="cp">
          draft
          <r>
            option
          </r>
        </indexterm>
      </findex>
      <findex index="fn" spaces=" ">
        <indexterm index="fn" number="69" mergedindex="cp">
          final
          <r>
            option
          </r>
        </indexterm>
      </findex>
      <findex index="fn" spaces=" ">
        <indexterm index="fn" number="70" mergedindex="cp">
          fleqn
          <r>
            option
          </r>
        </indexterm>
      </findex>
      <findex index="fn" spaces=" ">
        <indexterm index="fn" number="71" mergedindex="cp">
          landscape
          <r>
            option
          </r>
        </indexterm>
      </findex>
      <findex index="fn" spaces=" ">
        <indexterm index="fn" number="72" mergedindex="cp">
          leqno
          <r>
            option
          </r>
        </indexterm>
      </findex>
      <findex index="fn" spaces=" ">
        <indexterm index="fn" number="73" mergedindex="cp">
          openbib
          <r>
            option
          </r>
        </indexterm>
      </findex>
      <findex index="fn" spaces=" ">
        <indexterm index="fn" number="74" mergedindex="cp">
          titlepage
          <r>
            option
          </r>
        </indexterm>
      </findex>
      <findex index="fn" spaces=" ">
        <indexterm index="fn" number="75" mergedindex="cp">
          notitlepage
          <r>
            option
          </r>
        </indexterm>
      </findex>
      <para>
        Miscellaneous other options:
      </para>
      <table commandarg="code" spaces=" " endspaces=" ">
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                draft
              </itemformat>
            </item>
            <itemx spaces=" ">
              <itemformat command="code">
                final
              </itemformat>
            </itemx>
          </tableterm>
          <tableitem>
            <cindex index="cp" spaces=" ">
              <indexterm index="cp" number="106">
                black boxes, omitting
              </indexterm>
            </cindex>
            <para>
              Mark (
              <code>
                draft
              </code>
              ) or do not mark (
              <code>
                final
              </code>
              ) overfull boxes with a black box in the margin; default is
              <code>
                final
              </code>
              .
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                fleqn
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <cindex index="cp" spaces=" ">
              <indexterm index="cp" number="107">
                flush left equations
              </indexterm>
            </cindex>
            <cindex index="cp" spaces=" ">
              <indexterm index="cp" number="108">
                centered equations
              </indexterm>
            </cindex>
            <cindex index="cp" spaces=" ">
              <indexterm index="cp" number="109">
                equations, flush left vs.
Default handler: &noeos;
                 centered
              </indexterm>
            </cindex>
            <para>
              Put displayed formulas flush left; default is centered.
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                landscape
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <cindex index="cp" spaces=" ">
              <indexterm index="cp" number="110">
                landscape orientation
              </indexterm>
            </cindex>
            <cindex index="cp" spaces=" ">
              <indexterm index="cp" number="111">
                portrait orientation
              </indexterm>
            </cindex>
            <para>
              Selects landscape format; default is portrait.
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                leqno
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <cindex index="cp" spaces=" ">
              <indexterm index="cp" number="112">
                left-hand equation numbers
              </indexterm>
            </cindex>
            <cindex index="cp" spaces=" ">
              <indexterm index="cp" number="113">
                right-hand equation numbers
              </indexterm>
            </cindex>
            <cindex index="cp" spaces=" ">
              <indexterm index="cp" number="114">
                equation numbers, left vs.
Default handler: &noeos;
                 right
              </indexterm>
            </cindex>
            <para>
              Put equation numbers on the left side of equations; default is the right side.
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                openbib
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <cindex index="cp" spaces=" ">
              <indexterm index="cp" number="115">
                bibliography format, open
              </indexterm>
            </cindex>
            <para>
              Use
Default handler: &textldquo;
              open
Default handler: &textrdquo;
               bibliography format.
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                titlepage
              </itemformat>
            </item>
            <itemx spaces=" ">
              <itemformat command="code">
                notitlepage
              </itemformat>
            </itemx>
          </tableterm>
          <tableitem>
            <cindex index="cp" spaces=" ">
              <indexterm index="cp" number="116">
                title page, separate or run-in
              </indexterm>
            </cindex>
            <para>
              Specifies whether there is a separate page for the title information and for the abstract also, if there is one. The default for the
              <code>
                report
              </code>
               class is
              <code>
                titlepage
              </code>
              , for the other classes it is
              <code>
                notitlepage
              </code>
              .
            </para>
          </tableitem>
        </tableentry>
      </table>
      <para>
        The following options are not available with the
        <code>
          slides
        </code>
         class.
      </para>
      <findex index="fn" spaces=" ">
        <indexterm index="fn" number="76" mergedindex="cp">
          onecolumn
          <r>
            option
          </r>
        </indexterm>
      </findex>
      <findex index="fn" spaces=" ">
        <indexterm index="fn" number="77" mergedindex="cp">
          twocolumn
          <r>
            option
          </r>
        </indexterm>
      </findex>
      <findex index="fn" spaces=" ">
        <indexterm index="fn" number="78" mergedindex="cp">
          oneside
          <r>
            option
          </r>
        </indexterm>
      </findex>
      <findex index="fn" spaces=" ">
        <indexterm index="fn" number="79" mergedindex="cp">
          twoside
          <r>
            option
          </r>
        </indexterm>
      </findex>
      <findex index="fn" spaces=" ">
        <indexterm index="fn" number="80" mergedindex="cp">
          openright
          <r>
            option
          </r>
        </indexterm>
      </findex>
      <findex index="fn" spaces=" ">
        <indexterm index="fn" number="81" mergedindex="cp">
          openany
          <r>
            option
          </r>
        </indexterm>
      </findex>
      <table commandarg="code" spaces=" " endspaces=" ">
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                onecolumn
              </itemformat>
            </item>
            <itemx spaces=" ">
              <itemformat command="code">
                twocolumn
              </itemformat>
            </itemx>
          </tableterm>
          <tableitem>
            <para>
              Typeset in one or two columns; default is
              <code>
                onecolumn
              </code>
              .
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                oneside
              </itemformat>
            </item>
            <itemx spaces=" ">
              <itemformat command="code">
                twoside
              </itemformat>
            </itemx>
          </tableterm>
          <tableitem>
            <findex index="fn" spaces=" ">
              <indexterm index="fn" number="82" mergedindex="cp">
                \evensidemargin
              </indexterm>
            </findex>
            <findex index="fn" spaces=" ">
              <indexterm index="fn" number="83" mergedindex="cp">
                \oddsidemargin
              </indexterm>
            </findex>
Default handler: <!-- c xx TODO re-align on the French version which is more accurate. -->
            <para>
              Selects one- or two-sided layout; default is
              <code>
                oneside
              </code>
              , except that in the
              <code>
                book
              </code>
               class the default is
              <code>
                twoside
              </code>
              .
            </para>
            <para>
              For one-sided printing, the text is centered on the page. For two-sided printing, the
              <code>
                \evensidemargin
              </code>
               (
              <code>
                \oddsidemargin
              </code>
              ) parameter determines the distance on even (odd) numbered pages between the left side of the page and the text
Default handler: &textrsquo;
              s left margin, with
              <code>
                \oddsidemargin
              </code>
               being 40% of the difference between
              <code>
                \paperwidth
              </code>
               and
              <code>
                \textwidth
              </code>
              , and
              <code>
                \evensidemargin
              </code>
               is the remainder.
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                openright
              </itemformat>
            </item>
            <itemx spaces=" ">
              <itemformat command="code">
                openany
              </itemformat>
            </itemx>
          </tableterm>
          <tableitem>
            <para>
              Determines if a chapter should start on a right-hand page; default is
              <code>
                openright
              </code>
               for
              <code>
                book
              </code>
              , and
              <code>
                openany
              </code>
               for
              <code>
                report
              </code>
              .
            </para>
          </tableitem>
        </tableentry>
      </table>
      <findex index="fn" spaces=" ">
        <indexterm index="fn" number="84" mergedindex="cp">
          clock
          <r>
            option to
            <code>
              slides
            </code>
             class
          </r>
        </indexterm>
      </findex>
      <para>
        The
        <code>
          slides
        </code>
         class offers the option
        <code>
          clock
        </code>
         for printing the time at the bottom of each note.
      </para>
    </section>
    <node name="_005cusepackage" spaces=" ">
      <nodename>
        \usepackage
      </nodename>
      <nodenext automatic="on">
        Class and package creation
      </nodenext>
      <nodeprev automatic="on">
        Document class options
      </nodeprev>
      <nodeup automatic="on">
        Document classes
      </nodeup>
    </node>
    <section spaces=" ">
      <sectiontitle>
        <code>
          \usepackage
        </code>
        : Additional packages
      </sectiontitle>
      <anchor name="Additional-packages">
        Additional packages
      </anchor>
Default handler: <!-- c original node name -->
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="117">
          loading additional packages
        </indexterm>
      </cindex>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="118">
          packages, loading additional
        </indexterm>
      </cindex>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="119">
          additional packages, loading
        </indexterm>
      </cindex>
      <findex index="fn" spaces=" ">
        <indexterm index="fn" number="85" mergedindex="cp">
          \usepackage
        </indexterm>
      </findex>
      <para>
        To load a package
        <var>
          pkg
        </var>
        , with the package options given in the comma-separated list
        <var>
          options
        </var>
        :
      </para>
      <example endspaces=" ">
        <pre xml:space="preserve">
          \usepackage[
          <var>
            options
          </var>
          ]
Default handler: &lbrace;
          <var>
            pkg
          </var>
Default handler: &rbrace;
          [
          <var>
            mindate
          </var>
          ]
        </pre>
      </example>
      <para>
        To specify more than one package you can separate them with a comma, as in
        <code>
          \usepackage
Default handler: &lbrace;
          <var>
            pkg1
          </var>
          ,
          <var>
            pkg2
          </var>
          ,...
Default handler: &rbrace;
        </code>
        , or use multiple
        <code>
          \usepackage
        </code>
         commands.
      </para>
      <para>
        If the
        <var>
          mindate
        </var>
         optional argument is given,
Default handler: &latex;
         gives a warning if the loaded package has an earlier date, i.e., is too old. The
        <var>
          mindate
        </var>
         argument must be in the form
        <code>
          YYYY/MM/DD
        </code>
        . More info on this:
        <url>
          <urefurl>
            https://tex.stackexchange.com/questions/47743
          </urefurl>
        </url>
        .
      </para>
      <para>
        <code>
          \usepackage
        </code>
         must be used in the document preamble, between the
        <code>
          \documentclass
        </code>
         declaration and the
        <code>
          \begin
Default handler: &lbrace;
          document
Default handler: &rbrace;
        </code>
        . Occasionally it is necessary to load packages before the
        <code>
          \documentclass
        </code>
        ; see
        <code>
          \RequirePackage
        </code>
         for that (
        <pxref label="_005cRequirePackage">
          <xrefnodename>
            \RequirePackage
          </xrefnodename>
        </pxref>
        ).
      </para>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="120">
          global options
        </indexterm>
      </cindex>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="121">
          options, global
        </indexterm>
      </cindex>
      <para>
        Any options given in the global
        <code>
          \documentclass
        </code>
         command that are unknown to the selected document class are passed on to the packages loaded with
        <code>
          \usepackage
        </code>
        .
      </para>
    </section>
    <node name="Class-and-package-creation" spaces=" ">
      <nodename>
        Class and package creation
      </nodename>
      <nodeprev automatic="on">
        \usepackage
      </nodeprev>
      <nodeup automatic="on">
        Document classes
      </nodeup>
    </node>
    <section spaces=" ">
      <sectiontitle>
        Class and package creation
      </sectiontitle>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="122">
          document class commands
        </indexterm>
      </cindex>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="123">
          commands, document class
        </indexterm>
      </cindex>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="124">
          new class commands
        </indexterm>
      </cindex>
      <para>
        You can create new document classes and new packages. For instance, if your memos must satisfy some local requirements, such as a standard header for each page, then you could create a new class
        <code>
          smcmemo.cls
        </code>
         and begin your documents with
        <code>
          \documentclass
Default handler: &lbrace;
          smcmemo
Default handler: &rbrace;
        </code>
        .
      </para>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="125">
          class and package difference
        </indexterm>
      </cindex>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="126">
          difference between class and package
        </indexterm>
      </cindex>
      <para>
        What separates a package from a document class is that the commands in a package are useful across classes while those in a document class are specific to that class. Thus, a command to set page headers is for a package while a command to make the page headers be
        <code>
          Memo from the SMC Math Department
        </code>
         is for a class.
      </para>
      <para>
        Inside of a class or package definition you can use the at-sign
        <codeDefault handler: &arobase;
/>
         as a character in command names without having to surround the code containing that command with
        <code>
          \makeatletter
        </code>
         and
        <code>
          \makeatother
        </code>
         (
        <pxref label="_005cmakeatletter-_0026-_005cmakeatother">
          <xrefnodename>
            \makeatletter
            &
             \makeatother
          </xrefnodename>
        </pxref>
        ). This allows you to create commands that users will not accidentally redefine.
      </para>
      <para>
        It is also highly desirable to prefix class- or package-specific commands with your package name or similar string, to prevent your definitions from clashing with those from other packages. For instance, the class
        <code>
          smcmemo
        </code>
         might have commands
        <code>
          \smc
Default handler: &arobase;
          tolist
        </code>
        ,
        <code>
          \smc
Default handler: &arobase;
          fromlist
        </code>
        , etc.
      </para>
      <menu endspaces=" ">
        <menuentry>
          <menuleadingtext>
            *
          </menuleadingtext>
          <menunode>
            Class and package structure
          </menunode>
          <menuseparator>
            ::
          </menuseparator>
          <menudescription>
            <pre xml:space="preserve">
              Layout of the file.
            </pre>
          </menudescription>
        </menuentry>
      </menu>
      <node name="Class-and-package-structure" spaces=" ">
        <nodename>
          Class and package structure
        </nodename>
        <nodeup automatic="on">
          Class and package creation
        </nodeup>
      </node>
      <subsection spaces=" ">
        <sectiontitle>
          Class and package structure
        </sectiontitle>
        <cindex index="cp" spaces=" ">
          <indexterm index="cp" number="127">
            class and package structure
          </indexterm>
        </cindex>
        <cindex index="cp" spaces=" ">
          <indexterm index="cp" number="128">
            class file layout
          </indexterm>
        </cindex>
        <cindex index="cp" spaces=" ">
          <indexterm index="cp" number="129">
            package file layout
          </indexterm>
        </cindex>
        <cindex index="cp" spaces=" ">
          <indexterm index="cp" number="130">
            options, document class
          </indexterm>
        </cindex>
        <cindex index="cp" spaces=" ">
          <indexterm index="cp" number="131">
            options, package
          </indexterm>
        </cindex>
        <cindex index="cp" spaces=" ">
          <indexterm index="cp" number="132">
            class options
          </indexterm>
        </cindex>
        <cindex index="cp" spaces=" ">
          <indexterm index="cp" number="133">
            package options
          </indexterm>
        </cindex>
        <para>
          A class file or package file typically has four parts.
        </para>
        <enumerate first="1" endspaces=" ">
          <listitem>
            <para>
              In the
              <dfn>
                identification part
              </dfn>
              , the file says that it is a
Default handler: &latex;
               package or class and describes itself, using the
              <code>
                \NeedsTeXFormat
              </code>
               and
              <code>
                \ProvidesClass
              </code>
               or
              <code>
                \ProvidesPackage
              </code>
               commands.
            </para>
          </listitem>
          <listitem>
            <para>
              The
              <dfn>
                preliminary declarations part
              </dfn>
               declares some commands and can also load other files. Usually these commands will be those needed for the code used in the next part. For example, an
              <code>
                smcmemo
              </code>
               class might be called with an option to read in a file with a list of people for the to-head, as
              <code>
                \documentclass[mathto]
Default handler: &lbrace;
                smcmemo
Default handler: &rbrace;
              </code>
              , and therefore needs to define a command
              <code>
                \newcommand
Default handler: &lbrace;
                \setto
Default handler: &rbrace;
                [1]
Default handler: &lbrace;
                \def\
Default handler: &arobase;
                tolist
Default handler: &lbrace;
                #1
Default handler: &rbrace;
Default handler: &rbrace;
              </code>
               used in that file.
            </para>
          </listitem>
          <listitem>
            <para>
              In the
              <dfn>
                handle options part
              </dfn>
               the class or package declares and processes its options. Class options allow a user to start their document as
              <code>
                \documentclass[
                <var>
                  option list
                </var>
                ]
Default handler: &lbrace;
                <var>
                  class name
                </var>
Default handler: &rbrace;
              </code>
              , to modify the behavior of the class. An example is when you declare
              <code>
                \documentclass[11pt]
Default handler: &lbrace;
                article
Default handler: &rbrace;
              </code>
               to set the default document font size.
            </para>
          </listitem>
          <listitem>
            <para>
              Finally, in the
              <dfn>
                more declarations part
              </dfn>
               the class or package usually does most of its work: declaring new variables, commands and fonts, and loading other files.
            </para>
          </listitem>
        </enumerate>
        <cindex index="cp" spaces=" ">
          <indexterm index="cp" number="134">
            class file example
          </indexterm>
        </cindex>
        <para>
          Here is a starting class file, which should be saved as
          <file>
            stub.cls
          </file>
           where
Default handler: &latex;
           can find it, for example in the same directory as the
          <file>
            .tex
          </file>
           file.
        </para>
        <example endspaces=" ">
          <pre xml:space="preserve">
            \NeedsTeXFormat
Default handler: &lbrace;
            LaTeX2e
Default handler: &rbrace;
             \ProvidesClass
Default handler: &lbrace;
            stub
Default handler: &rbrace;
            [2017/07/06 stub to start building classes from] \DeclareOption*
Default handler: &lbrace;
            \PassOptionsToClass
Default handler: &lbrace;
            \CurrentOption
Default handler: &rbrace;
Default handler: &lbrace;
            article
Default handler: &rbrace;
Default handler: &rbrace;
             \ProcessOptions\relax \LoadClass
Default handler: &lbrace;
            article
Default handler: &rbrace;
          </pre>
        </example>
        <noindent/>
        <para>
          It identifies itself, handles the class options via the default of passing them all to the
          <code>
            article
          </code>
           class, and then loads the
          <code>
            article
          </code>
           class to provide the basis for this class
Default handler: &textrsquo;
          s code.
        </para>
        <findex index="fn" spaces=" ">
          <indexterm index="fn" number="86" mergedindex="cp">
            clsguide
            <r>
              document
            </r>
          </indexterm>
        </findex>
        <cindex index="cp" spaces=" ">
          <indexterm index="cp" number="135">
            Class Guide, document
          </indexterm>
        </cindex>
        <cindex index="cp" spaces=" ">
          <indexterm index="cp" number="136">
            class writing tutorial document
          </indexterm>
        </cindex>
        <para>
          For more, see the official guide for class and package writers, the Class Guide, at
          <url>
            <urefurl>
              https://ctan.org/pkg/clsguide
            </urefurl>
          </url>
           (much of the description here derives from this document), or the tutorial at
          <url>
            <urefurl>
              https://tug.org/TUGboat/tb26-3/tb84heff.pdf
            </urefurl>
          </url>
          .
        </para>
        <para>
          <xref label="Class-and-package-commands">
            <xrefnodename>
              Class and package commands
            </xrefnodename>
          </xref>
          , for some of the commands specifically intended for class and package writers.
        </para>
      </subsection>
    </section>
  </chapter>
  <node name="Fonts" spaces=" ">
    <nodename>
      Fonts
    </nodename>
    <nodenext automatic="on">
      Layout
    </nodenext>
    <nodeprev automatic="on">
      Document classes
    </nodeprev>
    <nodeup automatic="on">
      Top
    </nodeup>
  </node>
  <chapter spaces=" ">
    <sectiontitle>
      Fonts
    </sectiontitle>
    <anchor name="Typefaces">
      Typefaces
    </anchor>
Default handler: <!-- c old name -->
    <cindex index="cp" spaces=" ">
      <indexterm index="cp" number="137">
        typefaces
      </indexterm>
    </cindex>
    <cindex index="cp" spaces=" ">
      <indexterm index="cp" number="138">
        fonts
      </indexterm>
    </cindex>
    <paraDefault handler: &latex;
>
       comes with powerful font capacities. For one thing, its New Font Selection Scheme allows you to work easily with the font families in your document (for instance, see
Default handler: &nbsp;
      <ref label="Font-styles">
        <xrefnodename>
          Font styles
        </xrefnodename>
      </ref>
      ). And,
Default handler: &latex;
       documents can use most fonts that are available today, including versions of Times Roman, Helvetica, Courier, etc. (Note, though, that many fonts do not have support for mathematics.)
    </para>
    <para>
      The first typeface in the
Default handler: &tex;
       world was the Computer Modern family, developed by Donald Knuth. It is the default for
Default handler: &latex;
       documents and is still the most widely used. But changing to another font often only involves a few commands. For instance, putting the following in your preamble gives you a Palatino-like font, which is handsome and more readable online than many other fonts, while still allowing you to typeset mathematics. (This example is from Michael Sharpe,
      <url>
        <urefurl>
          https://math.ucsd.edu/~msharpe/RcntFnts.pdf
        </urefurl>
      </url>
      .)
    </para>
    <example endspaces=" ">
      <pre xml:space="preserve">
        \usepackage[osf]
Default handler: &lbrace;
        newpxtext
Default handler: &rbrace;
         % osf for text, not math \usepackage
Default handler: &lbrace;
        cabin
Default handler: &rbrace;
         % sans serif \usepackage[varqu,varl]
Default handler: &lbrace;
        inconsolata
Default handler: &rbrace;
         % sans serif typewriter \usepackage[bigdelims,vvarbb]
Default handler: &lbrace;
        newpxmath
Default handler: &rbrace;
         % bb from STIX \usepackage[cal=boondoxo]
Default handler: &lbrace;
        mathalfa
Default handler: &rbrace;
         % mathcal
      </pre>
    </example>
    <noindent/>
    <para>
      In addition, the
      <command>
        xelatex
      </command>
       or
      <command>
        lualatex
      </command>
       engines allow you to use any fonts on your system that are in OpenType or TrueType format (
      <pxref label="TeX-engines">
        <xrefnodenameDefault handler: &tex;
>
           engines
        </xrefnodename>
      </pxref>
      ).
    </para>
    <para>
      The
Default handler: &latex;
       Font Catalogue (
      <url>
        <urefurl>
          https://tug.org/FontCatalogue
        </urefurl>
      </url>
      ) shows font sample graphics and copy-and-pasteable source to use many fonts, including many with support for mathematics. It aims to cover all Latin alphabet free fonts available for easy use with
Default handler: &latex;
      .
    </para>
    <para>
      More information is also available from the
Default handler: &tex;
       Users Group, at
      <url>
        <urefurl>
          https://www.tug.org/fonts/
        </urefurl>
      </url>
      .
    </para>
    <menu endspaces=" ">
      <menuentry>
        <menuleadingtext>
          *
        </menuleadingtext>
        <menunode>
          fontenc package
        </menunode>
        <menuseparator>
          ::
        </menuseparator>
        <menudescription>
          <pre xml:space="preserve">
            Encoding of the font.
          </pre>
        </menudescription>
      </menuentry>
      <menuentry>
        <menuleadingtext>
          *
        </menuleadingtext>
        <menunode>
          Font styles
        </menunode>
        <menuseparator>
          ::
        </menuseparator>
        <menudescription>
          <pre xml:space="preserve">
            Select roman, italics, etc.
          </pre>
        </menudescription>
      </menuentry>
      <menuentry>
        <menuleadingtext>
          *
        </menuleadingtext>
        <menunode>
          Font sizes
        </menunode>
        <menuseparator>
          ::
        </menuseparator>
        <menudescription>
          <pre xml:space="preserve">
            Select point size.
          </pre>
        </menudescription>
      </menuentry>
      <menuentry>
        <menuleadingtext>
          *
        </menuleadingtext>
        <menunode>
          Low-level font commands
        </menunode>
        <menuseparator>
          ::
        </menuseparator>
        <menudescription>
          <pre xml:space="preserve">
            Select encoding, family, series, shape.
          </pre>
        </menudescription>
      </menuentry>
    </menu>
    <node name="fontenc-package" spaces=" ">
      <nodename>
        fontenc package
      </nodename>
      <nodenext automatic="on">
        Font styles
      </nodenext>
      <nodeup automatic="on">
        Fonts
      </nodeup>
    </node>
    <section spaces=" ">
      <sectiontitle>
        <code>
          fontenc
        </code>
         package
      </sectiontitle>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="139">
          font encoding
        </indexterm>
      </cindex>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="140">
          UTF-8, font support for
        </indexterm>
      </cindex>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="141">
          T1
        </indexterm>
      </cindex>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="142">
          OT1
        </indexterm>
      </cindex>
      <findex index="fn" spaces=" ">
        <indexterm index="fn" number="87" mergedindex="cp">
          fontenc
        </indexterm>
      </findex>
      <para>
        Synopsis:
      </para>
      <example endspaces=" ">
        <pre xml:space="preserve">
          \usepackage[
          <var>
            font_encoding
          </var>
          ]
Default handler: &lbrace;
          fontenc
Default handler: &rbrace;
        </pre>
      </example>
      <para>
        or
      </para>
      <example endspaces=" ">
        <pre xml:space="preserve">
          \usepackage[
          <var>
            font_encoding1
          </var>
          ,
          <var>
            font_encoding2
          </var>
          , ...]
Default handler: &lbrace;
          fontenc
Default handler: &rbrace;
        </pre>
      </example>
      <para>
        Specify the font encodings. A font encoding is a mapping of the character codes to the font glyphs that are used to typeset your output.
      </para>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="143">
          <r>
            package
          </r>
          ,
          <code>
            fontspec
          </code>
        </indexterm>
      </cindex>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="144">
          <code>
            fontspec
          </code>
          <r>
            package
          </r>
        </indexterm>
      </cindex>
      <para>
        This package only applies if you use the
        <code>
          pdflatex
        </code>
         engine (
        <pxref label="TeX-engines">
          <xrefnodenameDefault handler: &tex;
>
             engines
          </xrefnodename>
        </pxref>
        ). If you use the
        <command>
          xelatex
        </command>
         or
        <command>
          lualatex
        </command>
         engine then instead use the
        <code>
          fontspec
        </code>
         package.
      </para>
      <paraDefault handler: &tex;
Default handler: &textrsquo;
>
        s original font family, Computer Modern, has a limited character set. For instance, to make common accented characters you must use
        <code>
          \accent
        </code>
         (
        <pxref label="_005caccent">
          <xrefnodename>
            \accent
          </xrefnodename>
        </pxref>
        ) but this disables hyphenation.
Default handler: &tex;
         users have agreed on a number of standards to access the larger sets of characters provided by modern fonts. If you are using
        <command>
          pdflatex
        </command>
         then put this in the preamble
      </para>
      <example endspaces=" ">
        <pre xml:space="preserve">
          \usepackage[T1]
Default handler: &lbrace;
          fontenc
Default handler: &rbrace;
        </pre>
      </example>
      <noindent/>
      <para>
        gives you support for the most widespread European languages, including French, German, Italian, Polish, and others. In particular, if you have words with accented letters then
Default handler: &latex;
         will hyphenate them and your output can be copied and pasted. (The optional second line allows you to directly enter accented characters into your source file.)
      </para>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="145">
          <r>
            package
          </r>
          ,
          <code>
            lmodern
          </code>
        </indexterm>
      </cindex>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="146">
          <code>
            lmodern
          </code>
          <r>
            package
          </r>
        </indexterm>
      </cindex>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="147">
          <r>
            package
          </r>
          ,
          <code>
            cm-super
          </code>
        </indexterm>
      </cindex>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="148">
          <code>
            cm-super
          </code>
          <r>
            package
          </r>
        </indexterm>
      </cindex>
      <para>
        If you are using an encoding such as
        <code>
          T1
        </code>
         and the characters appear blurry or do not magnify well then your fonts may be bitmapped, sometimes called raster or Type
Default handler: &nbsp;
        3. You want vector fonts. Use a package such as
        <code>
          lmodern
        </code>
         or
        <code>
          cm-super
        </code>
         to get a font that extends
Default handler: &latex;
Default handler: &textrsquo;
        s default using vector fonts.
      </para>
      <para>
        For each
        <var>
          font_encoding
        </var>
         given as an option but not already declared, this package loads the encoding definition files, named
        <file>
          <var>
            font_encoding
          </var>
          enc.def
        </file>
        . It also sets
        <code>
          \encodingdefault
        </code>
         to be the last encoding in the option list.
      </para>
      <para>
        These are the common values for
        <var>
          font_encoding
        </var>
        :
      </para>
      <table commandarg="code" spaces=" " endspaces=" ">
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                OT1
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <cindex index="cp" spaces=" ">
              <indexterm index="cp" number="149">
                OT1 encoding
              </indexterm>
            </cindex>
            <para>
              The original 7-bit encoding for
Default handler: &tex;
              . Limited to mostly English characters.
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                OMS, OML
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <para>
              Math symbols and math letters encoding.
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                T1
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <cindex index="cp" spaces=" ">
              <indexterm index="cp" number="150">
                T1 encoding
              </indexterm>
            </cindex>
            <cindex index="cp" spaces=" ">
              <indexterm index="cp" number="151">
                Cork encoding
              </indexterm>
            </cindex>
            <paraDefault handler: &tex;
>
               text extended. Sometimes called the Cork encoding for the users group meeting where it was developed (1990). Gives access to most European accented characters. The most common option for this package.
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                TS1
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <cindex index="cp" spaces=" ">
              <indexterm index="cp" number="152">
                TS1 (text companion) encoding
              </indexterm>
            </cindex>
            <para>
              Text Companion encoding.
            </para>
          </tableitem>
        </tableentry>
      </table>
      <noindent/>
      <paraDefault handler: &latex;
Default handler: &textrsquo;
>
        s default is to load
        <code>
          OML
        </code>
        ,
        <code>
          T1
        </code>
        ,
        <code>
          OT1
        </code>
        , and then
        <code>
          OMS
        </code>
        , and set the default to
        <code>
          OT1
        </code>
        .
      </para>
      <para>
        Even if you do not use accented letters, you may need to specify a font encoding if your font requires it.
      </para>
      <para>
        If you use
        <code>
          T1
        </code>
Default handler: &nbsp;
        encoded fonts other than the default Computer Modern family then you may need to load the package that selects your fonts before loading
        <file>
          fontenc
        </file>
        , to prevent the system from loading any
        <code>
          T1
        </code>
Default handler: &nbsp;
        encoded fonts from the default.
      </para>
      <para>
        The
Default handler: &latex;
         team reserves encoding names starting with:
        <samp>
          T
        </samp>
         for the standard text encodings with 256 characters,
        <samp>
          TS
        </samp>
         for symbols that extend the corresponding T encodings,
        <samp>
          X
        </samp>
         for test encodings,
        <samp>
          M
        </samp>
         for standard math encodings with 256 characters,
        <samp>
          A
        </samp>
         for special applications,
        <samp>
          OT
        </samp>
         for standard text encodings with 128 characters, and
        <samp>
          OM
        </samp>
         for standard math encodings with 128 characters (
        <samp>
          O
        </samp>
         stands for
        <samp>
          obsolete
        </samp>
        ).
      </para>
      <para>
        This package provides a number of commands, detailed below. Many of them are encoding-specific, so if you have defined a command that works for one encoding but the current encoding is different then the command is not in effect.
      </para>
      <menu endspaces=" ">
        <menuentry>
          <menuleadingtext>
            *
          </menuleadingtext>
          <menunode>
            \DeclareFontEncoding
          </menunode>
          <menuseparator>
            ::
          </menuseparator>
          <menudescription>
            <pre xml:space="preserve">
              Define an encoding.
            </pre>
          </menudescription>
        </menuentry>
        <menuentry>
          <menuleadingtext>
            *
          </menuleadingtext>
          <menunode>
            \DeclareTextAccent
          </menunode>
          <menuseparator>
            ::
          </menuseparator>
          <menudescription>
            <pre xml:space="preserve">
              Define an accent in the encoding.
            </pre>
          </menudescription>
        </menuentry>
        <menuentry>
          <menuleadingtext>
            *
          </menuleadingtext>
          <menunode>
            \DeclareTextAccentDefault
          </menunode>
          <menuseparator>
            ::
          </menuseparator>
          <menudescription>
            <pre xml:space="preserve">
              Fallback for using an accent in the encoding.
            </pre>
          </menudescription>
        </menuentry>
        <menuentry>
          <menuleadingtext>
            *
          </menuleadingtext>
          <menunode>
            \DeclareTextCommand
            &
             \ProvideTextCommand
          </menunode>
          <menuseparator>
            ::
          </menuseparator>
          <menudescription>
            <pre xml:space="preserve">
              New encoding-specific command.
            </pre>
          </menudescription>
        </menuentry>
        <menuentry>
          <menuleadingtext>
            *
          </menuleadingtext>
          <menunode>
            \DeclareTextCommandDefault
            &
             \ProvideTextCommandDefault
          </menunode>
          <menuseparator>
            ::
          </menuseparator>
          <menudescription>
            <pre xml:space="preserve">
              Fallback for encoding-specific commands.
            </pre>
          </menudescription>
        </menuentry>
        <menuentry>
          <menuleadingtext>
            *
          </menuleadingtext>
          <menunode>
            \DeclareTextComposite
          </menunode>
          <menuseparator>
            ::
          </menuseparator>
          <menudescription>
            <pre xml:space="preserve">
              Directly access an accented glyph, in the encoding.
            </pre>
          </menudescription>
        </menuentry>
        <menuentry>
          <menuleadingtext>
            *
          </menuleadingtext>
          <menunode>
            \DeclareTextCompositeCommand
          </menunode>
          <menuseparator>
            ::
          </menuseparator>
          <menudescription>
            <pre xml:space="preserve">
              Run code in slot, in the encoding.
            </pre>
          </menudescription>
        </menuentry>
        <menuentry>
          <menuleadingtext>
            *
          </menuleadingtext>
          <menunode>
            \DeclareTextSymbol
          </menunode>
          <menuseparator>
            ::
          </menuseparator>
          <menudescription>
            <pre xml:space="preserve">
              Define a symbol in the encoding.
            </pre>
          </menudescription>
        </menuentry>
        <menuentry>
          <menuleadingtext>
            *
          </menuleadingtext>
          <menunode>
            \DeclareTextSymbolDefault
          </menunode>
          <menuseparator>
            ::
          </menuseparator>
          <menudescription>
            <pre xml:space="preserve">
              Fallback for a symbol in the encoding.
            </pre>
          </menudescription>
        </menuentry>
        <menuentry>
          <menuleadingtext>
            *
          </menuleadingtext>
          <menunode>
            \LastDeclaredEncoding
          </menunode>
          <menuseparator>
            ::
          </menuseparator>
          <menudescription>
            <pre xml:space="preserve">
              Save most recently declared encoding.
            </pre>
          </menudescription>
        </menuentry>
        <menuentry>
          <menuleadingtext>
            *
          </menuleadingtext>
          <menunode>
            \UseTextSymbol
            &
             \UseTextAccent
          </menunode>
          <menuseparator>
            ::
          </menuseparator>
          <menudescription>
            <pre xml:space="preserve">
              Temporarily switch to another encoding.
            </pre>
          </menudescription>
        </menuentry>
      </menu>
      <node name="_005cDeclareFontEncoding" spaces=" ">
        <nodename>
          \DeclareFontEncoding
        </nodename>
        <nodenext automatic="on">
          \DeclareTextAccent
        </nodenext>
        <nodeup automatic="on">
          fontenc package
        </nodeup>
      </node>
      <subsection spaces=" ">
        <sectiontitle>
          <code>
            \DeclareFontEncoding
          </code>
        </sectiontitle>
        <cindex index="cp" spaces=" ">
          <indexterm index="cp" number="153">
            font encoding, declaring
          </indexterm>
        </cindex>
        <cindex index="cp" spaces=" ">
          <indexterm index="cp" number="154">
            encoding, font
          </indexterm>
        </cindex>
        <cindex index="cp" spaces=" ">
          <indexterm index="cp" number="155">
            accents, defining
          </indexterm>
        </cindex>
        <findex index="fn" spaces=" ">
          <indexterm index="fn" number="88" mergedindex="cp">
            \DeclareFontEncoding
          </indexterm>
        </findex>
        <para>
          Synopsis:
        </para>
        <example endspaces=" ">
          <pre xml:space="preserve">
            \DeclareFontEncoding
Default handler: &lbrace;
            <var>
              encoding
            </var>
Default handler: &rbrace;
Default handler: &lbrace;
            <var>
              text-settings
            </var>
Default handler: &rbrace;
Default handler: &lbrace;
            <var>
              math-settings
            </var>
Default handler: &rbrace;
          </pre>
        </example>
        <para>
          Declare the font encoding
          <var>
            encoding
          </var>
          . It also saves the value of
          <var>
            encoding
          </var>
           in
          <code>
            \LastDeclaredEncoding
          </code>
           (
          <pxref label="_005cLastDeclaredEncoding">
            <xrefnodename>
              \LastDeclaredEncoding
            </xrefnodename>
          </pxref>
          ).
        </para>
        <para>
          The file
          <file>
            t1enc.def
          </file>
           contains this line (followed by many others).
        </para>
        <example endspaces=" ">
          <pre xml:space="preserve">
            \DeclareFontEncoding
Default handler: &lbrace;
            T1
Default handler: &rbrace;
Default handler: &lbrace;
Default handler: &rbrace;
Default handler: &lbrace;
Default handler: &rbrace;
          </pre>
        </example>
        <para>
          The
          <var>
            text-settings
          </var>
           are the commands that
Default handler: &latex;
           will run every time it switches from one encoding to another with the
          <code>
            \selectfont
          </code>
           and
          <code>
            \fontencoding
          </code>
           commands. The
          <var>
            math-settings
          </var>
           are the commands that
Default handler: &latex;
           will use whenever the font is accessed as a math alphabet.
        </para>
        <paraDefault handler: &latex;
>
           ignores any space characters inside
          <var>
            text-settings
          </var>
           and
          <var>
            math-settings
          </var>
          , to prevent unintended spaces in the output.
        </para>
        <para>
          If you invent an encoding you should pick a two or three letter name starting with
          <samp>
            L
          </samp>
           for
          <samp>
            local
          </samp>
          , or
          <samp>
            E
          </samp>
           for
          <samp>
            experimental
          </samp>
          .
        </para>
        <para>
          Note that output encoding files may be read several times by
Default handler: &latex;
           so using, e.g.,
          <code>
            \newcommand
          </code>
           may cause an error. In addition, such files should contain
          <code>
            \ProvidesFile
          </code>
           line (
          <pxref label="Class-and-package-commands">
            <xrefnodename>
              Class and package commands
            </xrefnodename>
          </pxref>
          ).
        </para>
        <para>
          Note also that you should use the
          <code>
            \...Default
          </code>
           commands only in a package, not in the encoding definition files, since those files should only contain declarations specific to that encoding.
        </para>
      </subsection>
      <node name="_005cDeclareTextAccent" spaces=" ">
        <nodename>
          \DeclareTextAccent
        </nodename>
        <nodenext automatic="on">
          \DeclareTextAccentDefault
        </nodenext>
        <nodeprev automatic="on">
          \DeclareFontEncoding
        </nodeprev>
        <nodeup automatic="on">
          fontenc package
        </nodeup>
      </node>
      <subsection spaces=" ">
        <sectiontitle>
          <code>
            \DeclareTextAccent
          </code>
        </sectiontitle>
        <cindex index="cp" spaces=" ">
          <indexterm index="cp" number="156">
            font encoding
          </indexterm>
        </cindex>
        <cindex index="cp" spaces=" ">
          <indexterm index="cp" number="157">
            accents, defining
          </indexterm>
        </cindex>
        <findex index="fn" spaces=" ">
          <indexterm index="fn" number="89" mergedindex="cp">
            \DeclareTextAccent
          </indexterm>
        </findex>
        <para>
          Synopsis:
        </para>
        <example endspaces=" ">
          <pre xml:space="preserve">
            \DeclareTextAccent
Default handler: &lbrace;
            <var>
              cmd
            </var>
Default handler: &rbrace;
Default handler: &lbrace;
            <var>
              encoding
            </var>
Default handler: &rbrace;
Default handler: &lbrace;
            <var>
              slot
            </var>
Default handler: &rbrace;
          </pre>
        </example>
        <para>
          Define an accent, to be put on top of other glyphs, in the encoding
          <var>
            encoding
          </var>
           at the location
          <var>
            slot
          </var>
          .
        </para>
        <cindex index="cp" spaces=" ">
          <indexterm index="cp" number="158">
            slot, font
          </indexterm>
        </cindex>
        <para>
          A
          <dfn>
            slot
          </dfn>
           is the number identifying a glyph within a font.
        </para>
        <para>
          This line from
          <file>
            t1enc.def
          </file>
           declares that to make a circumflex accent as in
          <code>
            \^A
          </code>
          , the system will put the accent in slot
Default handler: &nbsp;
          2 over the
          <samp>
            A
          </samp>
           character, which is represented in ASCII as
Default handler: &nbsp;
          65. (This holds unless there is a relevant
          <code>
            DeclareTextComposite
          </code>
           or
          <code>
            \DeclareTextCompositeCommand
          </code>
           declaration;
          <pxref label="_005cDeclareTextComposite">
            <xrefnodename>
              \DeclareTextComposite
            </xrefnodename>
          </pxref>
          .)
        </para>
        <example endspaces=" ">
          <pre xml:space="preserve">
            \DeclareTextAccent
Default handler: &lbrace;
            \^
Default handler: &rbrace;
Default handler: &lbrace;
            T1
Default handler: &rbrace;
Default handler: &lbrace;
            2
Default handler: &rbrace;
          </pre>
        </example>
        <para>
          If
          <var>
            cmd
          </var>
           has already been defined then
          <code>
            \DeclareTextAccent
          </code>
           does not give an error but it does log the redefinition in the transcript file.
        </para>
      </subsection>
      <node name="_005cDeclareTextAccentDefault" spaces=" ">
        <nodename>
          \DeclareTextAccentDefault
        </nodename>
        <nodenext automatic="on">
          \DeclareTextCommand
          &
           \ProvideTextCommand
        </nodenext>
        <nodeprev automatic="on">
          \DeclareTextAccent
        </nodeprev>
        <nodeup automatic="on">
          fontenc package
        </nodeup>
      </node>
      <subsection spaces=" ">
        <sectiontitle>
          <code>
            \DeclareTextAccentDefault
          </code>
        </sectiontitle>
        <cindex index="cp" spaces=" ">
          <indexterm index="cp" number="159">
            accents, defining
          </indexterm>
        </cindex>
        <findex index="fn" spaces=" ">
          <indexterm index="fn" number="90" mergedindex="cp">
            \DeclareTextAccent
          </indexterm>
        </findex>
        <findex index="fn" spaces=" ">
          <indexterm index="fn" number="91" mergedindex="cp">
            \DeclareTextAccentDefault
          </indexterm>
        </findex>
        <para>
          Synopsis:
        </para>
        <example endspaces=" ">
          <pre xml:space="preserve">
            \DeclareTextAccentDefault
Default handler: &lbrace;
            \
            <var>
              cmd
            </var>
Default handler: &rbrace;
Default handler: &lbrace;
            <var>
              encoding
            </var>
Default handler: &rbrace;
          </pre>
        </example>
        <para>
          If there is an encoding-specific accent command \
          <var>
            cmd
          </var>
           but there is no associated
          <code>
            \DeclareTextAccent
          </code>
           for that encoding then this command will pick up the slack, by saying to use it as described for
          <var>
            encoding
          </var>
          .
        </para>
        <para>
          For example, to make the encoding
          <code>
            OT1
          </code>
           be the default encoding for the accent
          <code>
            \
            "
          </code>
          , declare this.
        </para>
        <example endspaces=" ">
          <pre xml:space="preserve">
            \DeclareTextAccentDefault
Default handler: &lbrace;
            \
            "
Default handler: &rbrace;
Default handler: &lbrace;
            OT1
Default handler: &rbrace;
          </pre>
        </example>
        <noindent/>
        <para>
          If you issue a
          <code>
            \
            "
          </code>
           when the current encoding does not have a definition for that accent then
Default handler: &latex;
           will use the definition from
          <code>
            OT1
          </code>
        </para>
        <para>
          That is, this command is equivalent to this call (
          <pxref label="_005cUseTextSymbol-_0026-_005cUseTextAccent">
            <xrefnodename>
              \UseTextSymbol
              &
               \UseTextAccent
            </xrefnodename>
          </pxref>
          ).
        </para>
        <example endspaces=" ">
          <pre xml:space="preserve">
            \DeclareTextCommandDefault[1]
Default handler: &lbrace;
            \
            <var>
              cmd
            </var>
Default handler: &rbrace;
Default handler: &lbrace;
            \UseTextAccent
Default handler: &lbrace;
            <var>
              encoding
            </var>
Default handler: &rbrace;
Default handler: &lbrace;
            \
            <var>
              cmd
            </var>
Default handler: &rbrace;
Default handler: &lbrace;
            #1
Default handler: &rbrace;
Default handler: &rbrace;
          </pre>
        </example>
        <para>
          Note that
          <code>
            \DeclareTextAccentDefault
          </code>
           works for any one-argument
          <file>
            fontenc
          </file>
           command, not just the accent command.
        </para>
      </subsection>
      <node name="_005cDeclareTextCommand-_0026-_005cProvideTextCommand" spaces=" ">
        <nodename>
          \DeclareTextCommand
          &
           \ProvideTextCommand
        </nodename>
        <nodenext automatic="on">
          \DeclareTextCommandDefault
          &
           \ProvideTextCommandDefault
        </nodenext>
        <nodeprev automatic="on">
          \DeclareTextAccentDefault
        </nodeprev>
        <nodeup automatic="on">
          fontenc package
        </nodeup>
      </node>
      <subsection spaces=" ">
        <sectiontitle>
          <code>
            \DeclareTextCommand
          </code>
          &
          <code>
            \ProvideTextCommand
          </code>
        </sectiontitle>
        <anchor name="_005cDeclareTextCommand">
          \DeclareTextCommand
        </anchor>
        <anchor name="_005cProvideTextCommand">
          \ProvideTextCommand
        </anchor>
        <findex index="fn" spaces=" ">
          <indexterm index="fn" number="92" mergedindex="cp">
            \DeclareTextCommand
          </indexterm>
        </findex>
        <findex index="fn" spaces=" ">
          <indexterm index="fn" number="93" mergedindex="cp">
            \ProvideTextCommand
          </indexterm>
        </findex>
        <para>
          Synopsis, one of:
        </para>
        <example endspaces=" ">
          <pre xml:space="preserve">
            \DeclareTextCommand
Default handler: &lbrace;
            \
            <var>
              cmd
            </var>
Default handler: &rbrace;
Default handler: &lbrace;
            <var>
              encoding
            </var>
Default handler: &rbrace;
Default handler: &lbrace;
            <var>
              defn
            </var>
Default handler: &rbrace;
             \DeclareTextCommand
Default handler: &lbrace;
            \
            <var>
              cmd
            </var>
Default handler: &rbrace;
Default handler: &lbrace;
            <var>
              encoding
            </var>
Default handler: &rbrace;
            [
            <var>
              nargs
            </var>
            ]
Default handler: &lbrace;
            <var>
              defn
Default handler: &rbrace;
            </var>
             \DeclareTextCommand
Default handler: &lbrace;
            \
            <var>
              cmd
            </var>
Default handler: &rbrace;
Default handler: &lbrace;
            <var>
              encoding
            </var>
Default handler: &rbrace;
            [
            <var>
              nargs
            </var>
            ][
            <var>
              optargdefault
            </var>
            ]
Default handler: &lbrace;
            <var>
              defn
            </var>
Default handler: &rbrace;
          </pre>
        </example>
        <para>
          or one of:
        </para>
        <example endspaces=" ">
          <pre xml:space="preserve">
            \ProvideTextCommand
Default handler: &lbrace;
            \
            <var>
              cmd
            </var>
Default handler: &rbrace;
Default handler: &lbrace;
            <var>
              encoding
            </var>
Default handler: &rbrace;
Default handler: &lbrace;
            <var>
              defn
            </var>
Default handler: &rbrace;
             \ProvideTextCommand
Default handler: &lbrace;
            \
            <var>
              cmd
            </var>
Default handler: &rbrace;
Default handler: &lbrace;
            <var>
              encoding
            </var>
Default handler: &rbrace;
            [
            <var>
              nargs
            </var>
            ]
Default handler: &lbrace;
            <var>
              defn
            </var>
Default handler: &rbrace;
             \ProvideTextCommand
Default handler: &lbrace;
            \
            <var>
              cmd
            </var>
Default handler: &rbrace;
Default handler: &lbrace;
            <var>
              encoding
            </var>
Default handler: &rbrace;
            [
            <var>
              nargs
            </var>
            ][
            <var>
              optargdefault
            </var>
            ]
Default handler: &lbrace;
            <var>
              defn
            </var>
Default handler: &rbrace;
          </pre>
        </example>
        <para>
          Define the command
          <code>
            \
            <var>
              cmd
            </var>
          </code>
          , which will be specific to one encoding. The command name
          <var>
            cmd
          </var>
           must be preceded by a backslash,
          <code>
            \
          </code>
          . These commands can only appear in the preamble. Redefining \
          <var>
            cmd
          </var>
           does not cause an error. The defined command will be robust even if the code in
          <var>
            defn
          </var>
           is fragile (
          <pxref label="_005cprotect">
            <xrefnodename>
              \protect
            </xrefnodename>
          </pxref>
          ).
        </para>
        <para>
          For example, the file
          <file>
            t1enc.def
          </file>
           contains this line.
        </para>
        <example endspaces=" ">
          <pre xml:space="preserve">
            \DeclareTextCommand
Default handler: &lbrace;
            \textperthousand
Default handler: &rbrace;
Default handler: &lbrace;
            T1
Default handler: &rbrace;
Default handler: &lbrace;
            \%\char 24
Default handler: &rbrace;
          </pre>
        </example>
        <para>
          With that, you can express parts per thousand.
        </para>
        <example endspaces=" ">
          <pre xml:space="preserve">
            \usepackage[T1]
Default handler: &lbrace;
            fontenc
Default handler: &rbrace;
             % in preamble ... Legal limit is \( 0.8 \)\textperthousand.
          </pre>
        </example>
        <noindent/>
        <para>
          If you change the font encoding to
          <code>
            OT1
          </code>
           then you get an error like
          <samp>
            LaTeX Error: Command \textperthousand unavailable in encoding OT1
          </samp>
          .
        </para>
        <findex index="fn" spaces=" ">
          <indexterm index="fn" number="94" mergedindex="cp">
            \DeclareTextSymbol
          </indexterm>
        </findex>
        <para>
          The
          <code>
            \ProvideTextCommand
          </code>
           variant does the same, except that it does nothing if
          <code>
            \
            <var>
              cmd
            </var>
          </code>
           is already defined. The
          <code>
            \DeclareTextSymbol
          </code>
           command is faster than this one for simple slot-to-glyph association (
          <pxref label="_005cDeclareTextSymbol">
            <xrefnodename>
              \DeclareTextSymbol
            </xrefnodename>
          </pxref>
          )
        </para>
        <para>
          The optional
          <var>
            nargs
          </var>
           and
          <var>
            optargdefault
          </var>
           arguments play the same role here as in
          <code>
            \newcommand
          </code>
           (
          <pxref label="_005cnewcommand-_0026-_005crenewcommand">
            <xrefnodename>
              \newcommand
              &
               \renewcommand
            </xrefnodename>
          </pxref>
          ). Briefly,
          <var>
            nargs
          </var>
           is an integer from 0 to 9 specifying the number of arguments that the defined command
          <code>
            \
            <var>
              cmd
            </var>
          </code>
           takes. This number includes any optional argument. Omitting this argument is the same as specifying 0, meaning that
          <code>
            \
            <var>
              cmd
            </var>
          </code>
           will have no arguments. And, if
          <var>
            optargdefault
          </var>
           is present then the first argument of
          <code>
            \
            <var>
              cmd
            </var>
          </code>
           is optional, with default value
          <var>
            optargdefault
          </var>
           (which may be the empty string). If
          <var>
            optargdefault
          </var>
           is not present then
          <code>
            \
            <var>
              cmd
            </var>
          </code>
           does not take an optional argument.
        </para>
      </subsection>
      <node name="_005cDeclareTextCommandDefault-_0026-_005cProvideTextCommandDefault" spaces=" ">
        <nodename>
          \DeclareTextCommandDefault
          &
           \ProvideTextCommandDefault
        </nodename>
        <nodenext automatic="on">
          \DeclareTextComposite
        </nodenext>
        <nodeprev automatic="on">
          \DeclareTextCommand
          &
           \ProvideTextCommand
        </nodeprev>
        <nodeup automatic="on">
          fontenc package
        </nodeup>
      </node>
      <subsection spaces=" ">
        <sectiontitle>
          <code>
            \DeclareTextCommandDefault
          </code>
          &
          <code>
            \ProvideTextCommandDefault
          </code>
        </sectiontitle>
        <anchor name="_005cDeclareTextCommandDefault">
          \DeclareTextCommandDefault
        </anchor>
        <anchor name="_005cProvideTextCommandDefault">
          \ProvideTextCommandDefault
        </anchor>
        <findex index="fn" spaces=" ">
          <indexterm index="fn" number="95" mergedindex="cp">
            \DeclareTextCommandDefault
          </indexterm>
        </findex>
        <findex index="fn" spaces=" ">
          <indexterm index="fn" number="96" mergedindex="cp">
            \ProvideTextCommandDefault
          </indexterm>
        </findex>
        <para>
          Synopsis:
        </para>
        <example endspaces=" ">
          <pre xml:space="preserve">
            \DeclareTextCommandDefault
Default handler: &lbrace;
            \
            <var>
              cmd
            </var>
Default handler: &rbrace;
Default handler: &lbrace;
            <var>
              defn
            </var>
Default handler: &rbrace;
          </pre>
        </example>
        <para>
          or:
        </para>
        <example endspaces=" ">
          <pre xml:space="preserve">
            \ProvideTextCommandDefault
Default handler: &lbrace;
            \
            <var>
              cmd
            </var>
Default handler: &rbrace;
Default handler: &lbrace;
            <var>
              defn
            </var>
Default handler: &rbrace;
          </pre>
        </example>
        <para>
          Give a default definition for
          <code>
            \
            <var>
              cmd
            </var>
          </code>
          , for when that command is not defined in the encoding currently in force. This default should only use encodings known to be available.
        </para>
        <para>
          This makes
          <code>
            \copyright
          </code>
           available.
        </para>
        <example endspaces=" ">
          <pre xml:space="preserve">
            \DeclareTextCommandDefault
Default handler: &lbrace;
            \copyright
Default handler: &rbrace;
Default handler: &lbrace;
            \textcircled
Default handler: &lbrace;
            c
Default handler: &rbrace;
Default handler: &rbrace;
          </pre>
        </example>
        <noindent/>
        <para>
          It uses only an encoding (OMS) that is always available.
        </para>
        <para>
          The
          <code>
            \DeclareTextCommandDefault
          </code>
           should not occur in the encoding definition files since those files should declare only commands for use when you select that encoding. It should instead be in a package.
        </para>
        <para>
          As with the related non-default commands, the
          <code>
            \ProvideTextCommandDefault
          </code>
           has exactly the same behavior as
          <code>
            \DeclareTextCommandDefault
          </code>
           except that it does nothing if
          <code>
            \
            <var>
              cmd
            </var>
          </code>
           is already defined (
          <pxref label="_005cDeclareTextCommand-_0026-_005cProvideTextCommand">
            <xrefnodename>
              \DeclareTextCommand
              &
               \ProvideTextCommand
            </xrefnodename>
          </pxref>
          ). So, packages can use it to provide fallbacks that other packages can improve upon.
        </para>
      </subsection>
      <node name="_005cDeclareTextComposite" spaces=" ">
        <nodename>
          \DeclareTextComposite
        </nodename>
        <nodenext automatic="on">
          \DeclareTextCompositeCommand
        </nodenext>
        <nodeprev automatic="on">
          \DeclareTextCommandDefault
          &
           \ProvideTextCommandDefault
        </nodeprev>
        <nodeup automatic="on">
          fontenc package
        </nodeup>
      </node>
      <subsection spaces=" ">
        <sectiontitle>
          <code>
            \DeclareTextComposite
          </code>
        </sectiontitle>
        <cindex index="cp" spaces=" ">
          <indexterm index="cp" number="160">
            accents, defining
          </indexterm>
        </cindex>
        <findex index="fn" spaces=" ">
          <indexterm index="fn" number="97" mergedindex="cp">
            \DeclareTextComposite
          </indexterm>
        </findex>
        <para>
          Synopsis:
        </para>
        <example endspaces=" ">
          <pre xml:space="preserve">
            \DeclareTextComposite
Default handler: &lbrace;
            \
            <var>
              cmd
            </var>
Default handler: &rbrace;
Default handler: &lbrace;
            <var>
              encoding
            </var>
Default handler: &rbrace;
Default handler: &lbrace;
            <var>
              simple_object
            </var>
Default handler: &rbrace;
Default handler: &lbrace;
            <var>
              slot
            </var>
Default handler: &rbrace;
          </pre>
        </example>
        <para>
          Access an accented glyph directly, that is, without having to put an accent over a separate character.
        </para>
        <para>
          This line from
          <file>
            t1enc.def
          </file>
           means that
          <code>
            \^o
          </code>
           will cause
Default handler: &latex;
           to typeset lowercase
Default handler: &nbsp;
          <samp>
            o
          </samp>
           by taking the character directly from slot 224 in the font.
        </para>
        <example endspaces=" ">
          <pre xml:space="preserve">
            \DeclareTextComposite
Default handler: &lbrace;
            \^
Default handler: &rbrace;
Default handler: &lbrace;
            T1
Default handler: &rbrace;
Default handler: &lbrace;
            o
Default handler: &rbrace;
Default handler: &lbrace;
            244
Default handler: &rbrace;
          </pre>
        </example>
        <para>
          <xref label="fontenc-package">
            <xrefnodename>
              fontenc package
            </xrefnodename>
          </xref>
          , for a list of common encodings. The
          <var>
            simple_object
          </var>
           should be a single character or a single command. The
          <var>
            slot
          </var>
           argument is usually a positive integer represented in decimal (although octal or hexadecimal are possible). Normally \
          <var>
            cmd
          </var>
           has already been declared for this encoding, either with
          <code>
            \DeclareTextAccent
          </code>
           or with a one-argument
          <code>
            \DeclareTextCommand
          </code>
          . In
          <file>
            t1enc.def
          </file>
          , the above line follows the
          <code>
            \DeclareTextAccent
Default handler: &lbrace;
            \^
Default handler: &rbrace;
Default handler: &lbrace;
            T1
Default handler: &rbrace;
Default handler: &lbrace;
            2
Default handler: &rbrace;
          </code>
           command.
        </para>
      </subsection>
      <node name="_005cDeclareTextCompositeCommand" spaces=" ">
        <nodename>
          \DeclareTextCompositeCommand
        </nodename>
        <nodenext automatic="on">
          \DeclareTextSymbol
        </nodenext>
        <nodeprev automatic="on">
          \DeclareTextComposite
        </nodeprev>
        <nodeup automatic="on">
          fontenc package
        </nodeup>
      </node>
      <subsection spaces=" ">
        <sectiontitle>
          <code>
            \DeclareTextCompositeCommand
          </code>
        </sectiontitle>
        <cindex index="cp" spaces=" ">
          <indexterm index="cp" number="161">
            accents, defining
          </indexterm>
        </cindex>
        <findex index="fn" spaces=" ">
          <indexterm index="fn" number="98" mergedindex="cp">
            \DeclareTextCompositeCommand
          </indexterm>
        </findex>
        <para>
          Synopsis:
        </para>
        <example endspaces=" ">
          <pre xml:space="preserve">
            \DeclareTextCompositeCommand
Default handler: &lbrace;
            \
            <var>
              cmd
            </var>
Default handler: &rbrace;
Default handler: &lbrace;
            <var>
              encoding
            </var>
Default handler: &rbrace;
Default handler: &lbrace;
            <var>
              arg
            </var>
Default handler: &rbrace;
Default handler: &lbrace;
            <var>
              code
            </var>
Default handler: &rbrace;
          </pre>
        </example>
        <para>
          A more general version of
          <code>
            \DeclareTextComposite
          </code>
           that runs arbitrary code with
          <code>
            \
            <var>
              cmd
            </var>
          </code>
          .
        </para>
        <para>
          This allows accents on
          <samp>
            i
          </samp>
           to act like accents on dotless
Default handler: &nbsp;
          i,
          <code>
            \i
          </code>
          .
        </para>
        <example endspaces=" ">
          <pre xml:space="preserve">
            \DeclareTextCompositeCommand
Default handler: &lbrace;
            \'
Default handler: &rbrace;
Default handler: &lbrace;
            OT1
Default handler: &rbrace;
Default handler: &lbrace;
            i
Default handler: &rbrace;
Default handler: &lbrace;
            \'\i
Default handler: &rbrace;
          </pre>
        </example>
        <para>
          <xref label="fontenc-package">
            <xrefnodename>
              fontenc package
            </xrefnodename>
          </xref>
          , for a list of common encodings. Normally
          <code>
            \
            <var>
              cmd
            </var>
          </code>
           will have already been declared with
          <code>
            \DeclareTextAccent
          </code>
           or as a one argument
          <code>
            \DeclareTextCommand
          </code>
          .
        </para>
      </subsection>
      <node name="_005cDeclareTextSymbol" spaces=" ">
        <nodename>
          \DeclareTextSymbol
        </nodename>
        <nodenext automatic="on">
          \DeclareTextSymbolDefault
        </nodenext>
        <nodeprev automatic="on">
          \DeclareTextCompositeCommand
        </nodeprev>
        <nodeup automatic="on">
          fontenc package
        </nodeup>
      </node>
      <subsection spaces=" ">
        <sectiontitle>
          <code>
            \DeclareTextSymbol
          </code>
        </sectiontitle>
        <cindex index="cp" spaces=" ">
          <indexterm index="cp" number="162">
            symbol, defining
          </indexterm>
        </cindex>
        <findex index="fn" spaces=" ">
          <indexterm index="fn" number="99" mergedindex="cp">
            \DeclareTextSymbol
          </indexterm>
        </findex>
        <para>
          Synopsis:
        </para>
        <example endspaces=" ">
          <pre xml:space="preserve">
            \DeclareTextSymbol
Default handler: &lbrace;
            \
            <var>
              cmd
            </var>
Default handler: &rbrace;
Default handler: &lbrace;
            <var>
              encoding
            </var>
Default handler: &rbrace;
Default handler: &lbrace;
            <var>
              slot
            </var>
Default handler: &rbrace;
          </pre>
        </example>
        <para>
          Define a symbol in the encoding
          <var>
            encoding
          </var>
           at the location
          <var>
            slot
          </var>
          . Symbols defined in this way are for use in text, not mathematics.
        </para>
        <para>
          For example, this line from
          <file>
            t1enc.def
          </file>
           declares the number of the glyph to use for
          <u>
            00AB
          </u>
          , the left guillemet.
        </para>
        <example endspaces=" ">
          <pre xml:space="preserve">
            \DeclareTextSymbol
Default handler: &lbrace;
            \guillemetleft
Default handler: &rbrace;
Default handler: &lbrace;
            T1
Default handler: &rbrace;
Default handler: &lbrace;
            19
Default handler: &rbrace;
          </pre>
        </example>
        <noindent/>
        <para>
          The command
          <code>
            \DeclareTextCommand
Default handler: &lbrace;
            \guillemetleft
Default handler: &rbrace;
Default handler: &lbrace;
            T1
Default handler: &rbrace;
Default handler: &lbrace;
            \char 19
Default handler: &rbrace;
          </code>
           has the same effect but is slower (
          <pxref label="_005cDeclareTextCommand-_0026-_005cProvideTextCommand">
            <xrefnodename>
              \DeclareTextCommand
              &
               \ProvideTextCommand
            </xrefnodename>
          </pxref>
          ).
        </para>
        <para>
          <xref label="fontenc-package">
            <xrefnodename>
              fontenc package
            </xrefnodename>
          </xref>
          , for a list of common encodings. The
          <var>
            slot
          </var>
           can be specified in decimal, or octal (as in
          <code>
            '023
          </code>
          ), or hexadecimal (as in
          <code>
            "
            13
          </code>
          ), although decimal has the advantage that single quote or double quote could be redefined by another package.
        </para>
        <para>
          If
          <code>
            \
            <var>
              cmd
            </var>
          </code>
           has already been defined then
          <code>
            \DeclareTextSymbol
          </code>
           does not give an error but it does log the redefinition in the transcript file.
        </para>
      </subsection>
      <node name="_005cDeclareTextSymbolDefault" spaces=" ">
        <nodename>
          \DeclareTextSymbolDefault
        </nodename>
        <nodenext automatic="on">
          \LastDeclaredEncoding
        </nodenext>
        <nodeprev automatic="on">
          \DeclareTextSymbol
        </nodeprev>
        <nodeup automatic="on">
          fontenc package
        </nodeup>
      </node>
      <subsection spaces=" ">
        <sectiontitle>
          <code>
            \DeclareTextSymbolDefault
          </code>
        </sectiontitle>
        <cindex index="cp" spaces=" ">
          <indexterm index="cp" number="163">
            accents, defining
          </indexterm>
        </cindex>
        <findex index="fn" spaces=" ">
          <indexterm index="fn" number="100" mergedindex="cp">
            \DeclareTextSymbol
          </indexterm>
        </findex>
        <findex index="fn" spaces=" ">
          <indexterm index="fn" number="101" mergedindex="cp">
            \DeclareTextSymbolDefault
          </indexterm>
        </findex>
        <para>
          Synopsis:
        </para>
        <example endspaces=" ">
          <pre xml:space="preserve">
            \DeclareTextSymbolDefault
Default handler: &lbrace;
            \
            <var>
              cmd
            </var>
Default handler: &rbrace;
Default handler: &lbrace;
            <var>
              encoding
            </var>
Default handler: &rbrace;
          </pre>
        </example>
        <para>
          If there is an encoding-specific symbol command
          <code>
            \
            <var>
              cmd
            </var>
          </code>
           but there is no associated
          <code>
            \DeclareTextSymbol
          </code>
           for that encoding, then this command will pick up the slack, by saying to get the symbol as described for
          <var>
            encoding
          </var>
          .
        </para>
        <para>
          For example, to declare that if the current encoding has no meaning for
          <code>
            \textdollar
          </code>
           then use the one from
          <code>
            OT1
          </code>
          , declare this.
        </para>
        <example endspaces=" ">
          <pre xml:space="preserve">
            \DeclareTextSymbolDefault
Default handler: &lbrace;
            \textdollar
Default handler: &rbrace;
Default handler: &lbrace;
            OT1
Default handler: &rbrace;
          </pre>
        </example>
        <para>
          That is, this command is equivalent to this call (
          <pxref label="_005cUseTextSymbol-_0026-_005cUseTextAccent">
            <xrefnodename>
              \UseTextSymbol
              &
               \UseTextAccent
            </xrefnodename>
          </pxref>
          ).
        </para>
        <example endspaces=" ">
          <pre xml:space="preserve">
            \DeclareTextCommandDefault
Default handler: &lbrace;
            \
            <var>
              cmd
            </var>
Default handler: &rbrace;
Default handler: &lbrace;
            \UseTextSymbol
Default handler: &lbrace;
            <var>
              encoding
            </var>
Default handler: &rbrace;
Default handler: &lbrace;
            \
            <var>
              cmd
            </var>
Default handler: &rbrace;
Default handler: &rbrace;
          </pre>
        </example>
        <para>
          Note that
          <code>
            \DeclareTextSymbolDefault
          </code>
           can be used to define a default for any zero-argument
          <file>
            fontenc
          </file>
           command.
        </para>
      </subsection>
      <node name="_005cLastDeclaredEncoding" spaces=" ">
        <nodename>
          \LastDeclaredEncoding
        </nodename>
        <nodenext automatic="on">
          \UseTextSymbol
          &
           \UseTextAccent
        </nodenext>
        <nodeprev automatic="on">
          \DeclareTextSymbolDefault
        </nodeprev>
        <nodeup automatic="on">
          fontenc package
        </nodeup>
      </node>
      <subsection spaces=" ">
        <sectiontitle>
          <code>
            \LastDeclaredEncoding
          </code>
        </sectiontitle>
        <findex index="fn" spaces=" ">
          <indexterm index="fn" number="102" mergedindex="cp">
            \LastDeclaredEncoding
          </indexterm>
        </findex>
        <para>
          Synopsis:
        </para>
        <example endspaces=" ">
          <pre xml:space="preserve">
            \LastDeclaredEncoding
          </pre>
        </example>
        <para>
          Get the name of the most recently declared encoding. The
          <code>
            \DeclareFontEncoding
          </code>
           command stores the name so that it can be retrieved with this command (
          <pxref label="_005cDeclareFontEncoding">
            <xrefnodename>
              \DeclareFontEncoding
            </xrefnodename>
          </pxref>
          ).
        </para>
        <para>
          This relies on
          <code>
            \LastDeclaredEncoding
          </code>
           rather than give the name of the encoding explicitly.
        </para>
        <example endspaces=" ">
          <pre xml:space="preserve">
            \DeclareFontEncoding
Default handler: &lbrace;
            JH1
Default handler: &rbrace;
Default handler: &lbrace;
Default handler: &rbrace;
Default handler: &lbrace;
Default handler: &rbrace;
             \DeclareTextAccent
Default handler: &lbrace;
            \'
Default handler: &rbrace;
Default handler: &lbrace;
            \LastDeclaredEncoding
Default handler: &rbrace;
Default handler: &lbrace;
            0
Default handler: &rbrace;
          </pre>
        </example>
      </subsection>
      <node name="_005cUseTextSymbol-_0026-_005cUseTextAccent" spaces=" ">
        <nodename>
          \UseTextSymbol
          &
           \UseTextAccent
        </nodename>
        <nodeprev automatic="on">
          \LastDeclaredEncoding
        </nodeprev>
        <nodeup automatic="on">
          fontenc package
        </nodeup>
      </node>
      <subsection spaces=" ">
        <sectiontitle>
          <code>
            \UseTextSymbol
          </code>
          &
          <code>
            \UseTextAccent
          </code>
        </sectiontitle>
        <anchor name="_005cUseTextSymbol">
          \UseTextSymbol
        </anchor>
        <anchor name="_005cUseTextAccent">
          \UseTextAccent
        </anchor>
        <findex index="fn" spaces=" ">
          <indexterm index="fn" number="103" mergedindex="cp">
            \UseTextSymbol
          </indexterm>
        </findex>
        <findex index="fn" spaces=" ">
          <indexterm index="fn" number="104" mergedindex="cp">
            \UseTextAccent
          </indexterm>
        </findex>
        <para>
          Synopsis:
        </para>
        <example endspaces=" ">
          <pre xml:space="preserve">
            \UseTextSymbol
Default handler: &lbrace;
            <var>
              encoding
            </var>
Default handler: &rbrace;
Default handler: &lbrace;
            \
            <var>
              cmd
            </var>
Default handler: &rbrace;
          </pre>
        </example>
        <para>
          or:
        </para>
        <example endspaces=" ">
          <pre xml:space="preserve">
            \UseTextAccent
Default handler: &lbrace;
            <var>
              encoding
            </var>
Default handler: &rbrace;
Default handler: &lbrace;
            \
            <var>
              cmd
            </var>
Default handler: &rbrace;
Default handler: &lbrace;
            <var>
              text
            </var>
Default handler: &rbrace;
          </pre>
        </example>
        <para>
          Use a symbol or accent not from the current encoding.
        </para>
        <para>
          In general, to use a
          <file>
            fontenc
          </file>
           command in an encoding where it is not defined, and if the command has no arguments, then you can use it like this:
        </para>
        <example endspaces=" ">
          <pre xml:space="preserve">
            \UseTextSymbol
Default handler: &lbrace;
            OT1
Default handler: &rbrace;
Default handler: &lbrace;
            \ss
Default handler: &rbrace;
          </pre>
        </example>
        <noindent/>
        <para>
          which is equivalent to this (note the outer braces form a group, so
Default handler: &latex;
           reverts back to the prior encoding after the
          <code>
            \ss
          </code>
          ):
        </para>
        <example endspaces=" ">
          <pre xml:space="preserve"Default handler: &lbrace;
>
            \fontencoding
Default handler: &lbrace;
            OT1
Default handler: &rbrace;
            \selectfont\ss
Default handler: &rbrace;
          </pre>
        </example>
        <para>
          Similarly, to use a
          <file>
            fontenc
          </file>
           command in an encoding where it is not defined, and if the command has one argument, you can use it like this:
        </para>
        <example endspaces=" ">
          <pre xml:space="preserve">
            \UseTextAccent
Default handler: &lbrace;
            OT1
Default handler: &rbrace;
Default handler: &lbrace;
            \'
Default handler: &rbrace;
Default handler: &lbrace;
            a
Default handler: &rbrace;
          </pre>
        </example>
        <noindent/>
        <para>
          which is equivalent to this (again note the outer braces forming a group):
        </para>
        <example endspaces=" ">
          <pre xml:space="preserve"Default handler: &lbrace;
>
            fontencoding
Default handler: &lbrace;
            OT1
Default handler: &rbrace;
            \selectfont\'
Default handler: &lbrace;
            \fontencoding
Default handler: &lbrace;
            <var>
              enc_in_use
            </var>
Default handler: &rbrace;
            \selectfont a
Default handler: &rbrace;
Default handler: &rbrace;
          </pre>
        </example>
        <noindent/>
        <para>
          Here,
          <var>
            enc_in_use
          </var>
           is the encoding in force before this sequence of commands, so that
          <samp>
            a
          </samp>
           is typeset using the current encoding and only the accent is taken from
          <code>
            OT1
          </code>
          .
        </para>
      </subsection>
    </section>
    <node name="Font-styles" spaces=" ">
      <nodename>
        Font styles
      </nodename>
      <nodenext automatic="on">
        Font sizes
      </nodenext>
      <nodeprev automatic="on">
        fontenc package
      </nodeprev>
      <nodeup automatic="on">
        Fonts
      </nodeup>
    </node>
    <section spaces=" ">
      <sectiontitle>
        Font styles
      </sectiontitle>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="164">
          font styles
        </indexterm>
      </cindex>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="165">
          type styles
        </indexterm>
      </cindex>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="166">
          styles of text
        </indexterm>
      </cindex>
      <para>
        The following type style commands are supported by
Default handler: &latex;
        .
      </para>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="167">
          declaration form of font style commands
        </indexterm>
      </cindex>
      <para>
        In the table below the listed commands, the
        <code>
          \text...
        </code>
         commands, are used with an argument as in
        <code>
          \textit
Default handler: &lbrace;
          <var>
            text
          </var>
Default handler: &rbrace;
        </code>
        . This is the preferred form. But shown after it in parenthesis is the corresponding
        <dfn>
          declaration form
        </dfn>
        , which is often useful. This form takes no arguments, as in
        <codeDefault handler: &lbrace;
>
          \itshape
          <var>
            text
          </var>
Default handler: &rbrace;
        </code>
        . The scope of the declaration form lasts until the next type style command or the end of the current group. In addition, each has an environment form such as
        <code>
          \begin
Default handler: &lbrace;
          itshape
Default handler: &rbrace;
          ...\end
Default handler: &lbrace;
          itshape
Default handler: &rbrace;
        </code>
        , which we
Default handler: &textrsquo;
        ll describe further at the end of the section.
      </para>
      <para>
        These commands, in any of the three forms, are cumulative; for instance you can get bold sans serif by saying either of
        <code>
          \sffamily\bfseries
        </code>
         or
        <code>
          \bfseries\sffamily
        </code>
        .
      </para>
      <anchor name="_005cnocorrlist">
        \nocorrlist
      </anchor>
      <anchor name="_005cnocorr">
        \nocorr
      </anchor>
      <findex index="fn" spaces=" ">
        <indexterm index="fn" number="105" mergedindex="cp">
          \nocorrlist
        </indexterm>
      </findex>
      <findex index="fn" spaces=" ">
        <indexterm index="fn" number="106" mergedindex="cp">
          \nocorr
        </indexterm>
      </findex>
      <para>
        One advantage of these commands is that they automatically insert italic corrections if needed (
        <pxref label="_005c_002f">
          <xrefnodename>
            \/
          </xrefnodename>
        </pxref>
        ). Specifically, they insert the italic correction unless the following character is in the list
        <code>
          \nocorrlist
        </code>
        , which by default consists of period and comma. To suppress the automatic insertion of italic correction, use
        <code>
          \nocorr
        </code>
         at the start or end of the command argument, such as
        <code>
          \textit
Default handler: &lbrace;
          \nocorr text
Default handler: &rbrace;
        </code>
         or
        <code>
          \textsc
Default handler: &lbrace;
          text \nocorr
Default handler: &rbrace;
        </code>
        .
      </para>
      <table commandarg="code" spaces=" " endspaces=" ">
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                \textrm (\rmfamily)
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <findex index="fn" spaces=" ">
              <indexterm index="fn" number="107" mergedindex="cp">
                \textrm
              </indexterm>
            </findex>
            <findex index="fn" spaces=" ">
              <indexterm index="fn" number="108" mergedindex="cp">
                \rmfamily
              </indexterm>
            </findex>
            <para>
              Roman.
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                \textit (\itshape)
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <findex index="fn" spaces=" ">
              <indexterm index="fn" number="109" mergedindex="cp">
                \textit
              </indexterm>
            </findex>
            <findex index="fn" spaces=" ">
              <indexterm index="fn" number="110" mergedindex="cp">
                \itshape
              </indexterm>
            </findex>
            <para>
              Italics.
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                \textmd (\mdseries)
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <findex index="fn" spaces=" ">
              <indexterm index="fn" number="111" mergedindex="cp">
                \textmd
              </indexterm>
            </findex>
            <findex index="fn" spaces=" ">
              <indexterm index="fn" number="112" mergedindex="cp">
                \mdseries
              </indexterm>
            </findex>
            <para>
              Medium weight (default).
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                \textbf (\bfseries)
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <findex index="fn" spaces=" ">
              <indexterm index="fn" number="113" mergedindex="cp">
                \textbf
              </indexterm>
            </findex>
            <findex index="fn" spaces=" ">
              <indexterm index="fn" number="114" mergedindex="cp">
                \bfseries
              </indexterm>
            </findex>
            <para>
              Boldface.
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                \textup (\upshape)
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <findex index="fn" spaces=" ">
              <indexterm index="fn" number="115" mergedindex="cp">
                \textup
              </indexterm>
            </findex>
            <findex index="fn" spaces=" ">
              <indexterm index="fn" number="116" mergedindex="cp">
                \upshape
              </indexterm>
            </findex>
            <para>
              Upright (default).
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                \textsl (\slshape)
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <findex index="fn" spaces=" ">
              <indexterm index="fn" number="117" mergedindex="cp">
                \textsl
              </indexterm>
            </findex>
            <findex index="fn" spaces=" ">
              <indexterm index="fn" number="118" mergedindex="cp">
                \slshape
              </indexterm>
            </findex>
            <para>
              Slanted.
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                \textsf (\sffamily)
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <findex index="fn" spaces=" ">
              <indexterm index="fn" number="119" mergedindex="cp">
                \textsf
              </indexterm>
            </findex>
            <findex index="fn" spaces=" ">
              <indexterm index="fn" number="120" mergedindex="cp">
                \sffamily
              </indexterm>
            </findex>
            <para>
              Sans serif.
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                \textsc (\scshape)
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <findex index="fn" spaces=" ">
              <indexterm index="fn" number="121" mergedindex="cp">
                \textsc
              </indexterm>
            </findex>
            <findex index="fn" spaces=" ">
              <indexterm index="fn" number="122" mergedindex="cp">
                \scshape
              </indexterm>
            </findex>
            <para>
              Small caps.
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                \texttt (\ttfamily)
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <findex index="fn" spaces=" ">
              <indexterm index="fn" number="123" mergedindex="cp">
                \texttt
              </indexterm>
            </findex>
            <findex index="fn" spaces=" ">
              <indexterm index="fn" number="124" mergedindex="cp">
                \ttfamily
              </indexterm>
            </findex>
            <para>
              Typewriter.
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                \textnormal (\normalfont)
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <findex index="fn" spaces=" ">
              <indexterm index="fn" number="125" mergedindex="cp">
                \textnormal
              </indexterm>
            </findex>
            <findex index="fn" spaces=" ">
              <indexterm index="fn" number="126" mergedindex="cp">
                \normalfont
              </indexterm>
            </findex>
            <para>
              Main document font.
            </para>
          </tableitem>
        </tableentry>
      </table>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="168">
          emphasis
        </indexterm>
      </cindex>
      <findex index="fn" spaces=" ">
        <indexterm index="fn" number="127" mergedindex="cp">
          \emph
        </indexterm>
      </findex>
      <para>
        Although it also changes fonts, the
        <code>
          \emph
Default handler: &lbrace;
          <var>
            text
          </var>
Default handler: &rbrace;
        </code>
         command is semantic, for
        <var>
          text
        </var>
         to be emphasized, and should not be used as a substitute for
        <code>
          \textit
        </code>
        . For example,
        <code>
          \emph
Default handler: &lbrace;
          <var>
            start text
          </var>
           \emph
Default handler: &lbrace;
          <var>
            middle text
          </var>
Default handler: &rbrace;
          <var>
            end text
          </var>
Default handler: &rbrace;
        </code>
         will result in the
        <var>
          start text
        </var>
         and
        <var>
          end text
        </var>
         in italics, but
        <var>
          middle text
        </var>
         will be in roman.
      </para>
      <paraDefault handler: &latex;
>
         also provides the following commands, which unconditionally switch to the given style, that is, are
        <emph>
          not
        </emph>
         cumulative. They are used as declarations:
        <codeDefault handler: &lbrace;
>
          \
          <var>
            cmd
          </var>
          ...
Default handler: &rbrace;
        </code>
         instead of
        <code>
          \
          <var>
            cmd
          </var>
Default handler: &lbrace;
          ...
Default handler: &rbrace;
        </code>
        .
      </para>
      <para>
        (The unconditional commands below are an older version of font switching. The earlier commands are an improvement in most circumstances. But sometimes an unconditional font switch is what is needed.)
      </para>
      <ftable commandarg="code" spaces=" " endspaces=" ">
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                <indexterm index="fn" number="128" mergedindex="cp">
                  \bf
                </indexterm>
                \bf
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <cindex index="cp" spaces=" ">
              <indexterm index="cp" number="169">
                bold font
              </indexterm>
            </cindex>
            <para>
              Switch to bold face.
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                <indexterm index="fn" number="129" mergedindex="cp">
                  \cal
                </indexterm>
                \cal
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <cindex index="cp" spaces=" ">
              <indexterm index="cp" number="170">
                script letters for math
              </indexterm>
            </cindex>
            <cindex index="cp" spaces=" ">
              <indexterm index="cp" number="171">
                calligraphic letters for math
              </indexterm>
            </cindex>
            <para>
              Switch to calligraphic letters for math.
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                <indexterm index="fn" number="130" mergedindex="cp">
                  \it
                </indexterm>
                \it
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <cindex index="cp" spaces=" ">
              <indexterm index="cp" number="172">
                italic font
              </indexterm>
            </cindex>
            <para>
              Italics.
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                <indexterm index="fn" number="131" mergedindex="cp">
                  \rm
                </indexterm>
                \rm
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <cindex index="cp" spaces=" ">
              <indexterm index="cp" number="173">
                roman font
              </indexterm>
            </cindex>
            <para>
              Roman.
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                <indexterm index="fn" number="132" mergedindex="cp">
                  \sc
                </indexterm>
                \sc
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <cindex index="cp" spaces=" ">
              <indexterm index="cp" number="174">
                small caps font
              </indexterm>
            </cindex>
            <para>
              Small caps.
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                <indexterm index="fn" number="133" mergedindex="cp">
                  \sf
                </indexterm>
                \sf
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <cindex index="cp" spaces=" ">
              <indexterm index="cp" number="175">
                sans serif font
              </indexterm>
            </cindex>
            <para>
              Sans serif.
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                <indexterm index="fn" number="134" mergedindex="cp">
                  \sl
                </indexterm>
                \sl
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <cindex index="cp" spaces=" ">
              <indexterm index="cp" number="176">
                slanted font
              </indexterm>
            </cindex>
            <cindex index="cp" spaces=" ">
              <indexterm index="cp" number="177">
                oblique font
              </indexterm>
            </cindex>
            <para>
              Slanted (oblique).
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                <indexterm index="fn" number="135" mergedindex="cp">
                  \tt
                </indexterm>
                \tt
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <cindex index="cp" spaces=" ">
              <indexterm index="cp" number="178">
                typewriter font
              </indexterm>
            </cindex>
            <cindex index="cp" spaces=" ">
              <indexterm index="cp" number="179">
                monospace font
              </indexterm>
            </cindex>
            <cindex index="cp" spaces=" ">
              <indexterm index="cp" number="180">
                fixed-width font
              </indexterm>
            </cindex>
            <para>
              Typewriter (monospace, fixed-width).
            </para>
          </tableitem>
        </tableentry>
      </ftable>
      <para>
        The
        <code>
          \em
        </code>
         command is the unconditional version of
        <code>
          \emph
        </code>
        .
      </para>
      <para>
        The following commands are for use in math mode. They are not cumulative, so
        <code>
          \mathbf
Default handler: &lbrace;
          \mathit
Default handler: &lbrace;
          <var>
            symbol
          </var>
Default handler: &rbrace;
Default handler: &rbrace;
        </code>
         does not create a boldface and italic
        <var>
          symbol
        </var>
        ; instead, it will just be in italics. This is because typically math symbols need consistent typographic treatment, regardless of the surrounding environment.
      </para>
      <table commandarg="code" spaces=" " endspaces=" ">
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                \mathrm
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <findex index="fn" spaces=" ">
              <indexterm index="fn" number="136" mergedindex="cp">
                \mathrm
              </indexterm>
            </findex>
            <para>
              Roman, for use in math mode.
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                \mathbf
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <findex index="fn" spaces=" ">
              <indexterm index="fn" number="137" mergedindex="cp">
                \mathbf
              </indexterm>
            </findex>
            <para>
              Boldface, for use in math mode.
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                \mathsf
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <findex index="fn" spaces=" ">
              <indexterm index="fn" number="138" mergedindex="cp">
                \mathsf
              </indexterm>
            </findex>
            <para>
              Sans serif, for use in math mode.
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                \mathtt
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <findex index="fn" spaces=" ">
              <indexterm index="fn" number="139" mergedindex="cp">
                \mathtt
              </indexterm>
            </findex>
            <para>
              Typewriter, for use in math mode.
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                \mathit
              </itemformat>
            </item>
            <itemx spaces=" ">
              <itemformat command="code">
                (\mit)
              </itemformat>
            </itemx>
          </tableterm>
          <tableitem>
            <para>
              Italics, for use in math mode.
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                \mathnormal
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <findex index="fn" spaces=" ">
              <indexterm index="fn" number="140" mergedindex="cp">
                \mathnormal
              </indexterm>
            </findex>
            <para>
              For use in math mode, e.g., inside another type style declaration.
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                \mathcal
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <findex index="fn" spaces=" ">
              <indexterm index="fn" number="141" mergedindex="cp">
                \mathcal
              </indexterm>
            </findex>
            <para>
              Calligraphic letters, for use in math mode.
            </para>
          </tableitem>
        </tableentry>
      </table>
      <anchor name="_005cmathversion">
        \mathversion
      </anchor>
      <findex index="fn" spaces=" ">
        <indexterm index="fn" number="142" mergedindex="cp">
          \mathversion
        </indexterm>
      </findex>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="181">
          math, bold
        </indexterm>
      </cindex>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="182">
          bold math
        </indexterm>
      </cindex>
      <para>
        In addition, the command
        <code>
          \mathversion
Default handler: &lbrace;
          bold
Default handler: &rbrace;
        </code>
         can be used for switching to bold letters and symbols in formulas.
        <code>
          \mathversion
Default handler: &lbrace;
          normal
Default handler: &rbrace;
        </code>
         restores the default.
      </para>
      <anchor name="_005coldstylenums">
        \oldstylenums
      </anchor>
      <findex index="fn" spaces=" ">
        <indexterm index="fn" number="143" mergedindex="cp">
          \oldstylenums
        </indexterm>
      </findex>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="183">
          numerals, old-style
        </indexterm>
      </cindex>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="184">
          old-style numerals
        </indexterm>
      </cindex>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="185">
          lining numerals
        </indexterm>
      </cindex>
      <para>
        Finally, the command
        <code>
          \oldstylenums
Default handler: &lbrace;
          <var>
            numerals
          </var>
Default handler: &rbrace;
        </code>
         will typeset so-called
Default handler: &textldquo;
        old-style
Default handler: &textrdquo;
         numerals, which have differing heights and depths (and sometimes widths) from the standard
Default handler: &textldquo;
        lining
Default handler: &textrdquo;
         numerals, which all have the same height as uppercase letters.
Default handler: &latex;
Default handler: &textrsquo;
        s default fonts support this, and will respect
        <code>
          \textbf
        </code>
         (but not other styles; there are no italic old-style numerals in Computer Modern). Many other fonts have old-style numerals also; sometimes package options are provided to make them the default. FAQ entry:
        <url>
          <urefurl>
            https://www.texfaq.org/FAQ-osf
          </urefurl>
        </url>
        .
      </para>
    </section>
    <node name="Font-sizes" spaces=" ">
      <nodename>
        Font sizes
      </nodename>
      <nodenext automatic="on">
        Low-level font commands
      </nodenext>
      <nodeprev automatic="on">
        Font styles
      </nodeprev>
      <nodeup automatic="on">
        Fonts
      </nodeup>
    </node>
    <section spaces=" ">
      <sectiontitle>
        Font sizes
      </sectiontitle>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="186">
          font sizes
        </indexterm>
      </cindex>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="187">
          typeface sizes
        </indexterm>
      </cindex>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="188">
          sizes of text
        </indexterm>
      </cindex>
      <para>
        The following standard type size commands are supported by
Default handler: &latex;
        . The table shows the command name and the corresponding actual font size used (in points) with the
        <samp>
          10pt
        </samp>
        ,
        <samp>
          11pt
        </samp>
        , and
        <samp>
          12pt
        </samp>
         document size options, respectively (
        <pxref label="Document-class-options">
          <xrefnodename>
            Document class options
          </xrefnodename>
        </pxref>
        ).
      </para>
      <findex index="fn" spaces=" ">
        <indexterm index="fn" number="144" mergedindex="cp">
          \tiny
        </indexterm>
      </findex>
      <findex index="fn" spaces=" ">
        <indexterm index="fn" number="145" mergedindex="cp">
          \scriptsize
        </indexterm>
      </findex>
      <findex index="fn" spaces=" ">
        <indexterm index="fn" number="146" mergedindex="cp">
          \footnotesize
        </indexterm>
      </findex>
      <findex index="fn" spaces=" ">
        <indexterm index="fn" number="147" mergedindex="cp">
          \small
        </indexterm>
      </findex>
      <findex index="fn" spaces=" ">
        <indexterm index="fn" number="148" mergedindex="cp">
          \normalsize
        </indexterm>
      </findex>
      <findex index="fn" spaces=" ">
        <indexterm index="fn" number="149" mergedindex="cp">
          \large
        </indexterm>
      </findex>
      <findex index="fn" spaces=" ">
        <indexterm index="fn" number="150" mergedindex="cp">
          \Large
        </indexterm>
      </findex>
      <findex index="fn" spaces=" ">
        <indexterm index="fn" number="151" mergedindex="cp">
          \LARGE
        </indexterm>
      </findex>
      <findex index="fn" spaces=" ">
        <indexterm index="fn" number="152" mergedindex="cp">
          \huge
        </indexterm>
      </findex>
      <findex index="fn" spaces=" ">
        <indexterm index="fn" number="153" mergedindex="cp">
          \Huge
        </indexterm>
      </findex>
      <multitable spaces=" " endspaces=" ">
        <columnprototypes>
          <columnprototype bracketed="on">
            <code>
              \normalsize
            </code>
             (default)
            <spacecmd type="spc"/>
            <spacecmd type="spc"/>
          </columnprototype>
          <columnprototype bracketed="on">
            24.88
            <spacecmd type="spc"/>
            <spacecmd type="spc"/>
          </columnprototype>
          <columnprototype bracketed="on">
            24.88
            <spacecmd type="spc"/>
            <spacecmd type="spc"/>
          </columnprototype>
          <columnprototype bracketed="on">
            24.88
          </columnprototype>
        </columnprototypes>
        <thead>
          <row>
            <entry command="headitem">
              <para>
                Command
              </para>
            </entry>
            <entry command="tab">
              <para>
                <code>
                  10pt
                </code>
              </para>
            </entry>
            <entry command="tab">
              <para>
                <code>
                  11pt
                </code>
              </para>
            </entry>
            <entry command="tab">
              <para>
                <code>
                  12pt
                </code>
              </para>
            </entry>
          </row>
        </thead>
        <tbody>
          <row>
            <entry command="item">
              <para>
                <code>
                  \tiny
                </code>
              </para>
            </entry>
            <entry command="tab">
              <para>
                5
              </para>
            </entry>
            <entry command="tab">
              <para>
                6
              </para>
            </entry>
            <entry command="tab">
              <para>
                6
              </para>
            </entry>
          </row>
          <row>
            <entry command="item">
              <para>
                <code>
                  \scriptsize
                </code>
              </para>
            </entry>
            <entry command="tab">
              <para>
                7
              </para>
            </entry>
            <entry command="tab">
              <para>
                8
              </para>
            </entry>
            <entry command="tab">
              <para>
                8
              </para>
            </entry>
          </row>
          <row>
            <entry command="item">
              <para>
                <code>
                  \footnotesize
                </code>
              </para>
            </entry>
            <entry command="tab">
              <para>
                8
              </para>
            </entry>
            <entry command="tab">
              <para>
                9
              </para>
            </entry>
            <entry command="tab">
              <para>
                10
              </para>
            </entry>
          </row>
          <row>
            <entry command="item">
              <para>
                <code>
                  \small
                </code>
              </para>
            </entry>
            <entry command="tab">
              <para>
                9
              </para>
            </entry>
            <entry command="tab">
              <para>
                10
              </para>
            </entry>
            <entry command="tab">
              <para>
                10.95
              </para>
            </entry>
          </row>
          <row>
            <entry command="item">
              <para>
                <code>
                  \normalsize
                </code>
                 (default)
              </para>
            </entry>
            <entry command="tab">
              <para>
                10
              </para>
            </entry>
            <entry command="tab">
              <para>
                10.95
              </para>
            </entry>
            <entry command="tab">
              <para>
                12
              </para>
            </entry>
          </row>
          <row>
            <entry command="item">
              <para>
                <code>
                  \large
                </code>
              </para>
            </entry>
            <entry command="tab">
              <para>
                12
              </para>
            </entry>
            <entry command="tab">
              <para>
                12
              </para>
            </entry>
            <entry command="tab">
              <para>
                14.4
              </para>
            </entry>
          </row>
          <row>
            <entry command="item">
              <para>
                <code>
                  \Large
                </code>
              </para>
            </entry>
            <entry command="tab">
              <para>
                14.4
              </para>
            </entry>
            <entry command="tab">
              <para>
                14.4
              </para>
            </entry>
            <entry command="tab">
              <para>
                17.28
              </para>
            </entry>
          </row>
          <row>
            <entry command="item">
              <para>
                <code>
                  \LARGE
                </code>
              </para>
            </entry>
            <entry command="tab">
              <para>
                17.28
              </para>
            </entry>
            <entry command="tab">
              <para>
                17.28
              </para>
            </entry>
            <entry command="tab">
              <para>
                20.74
              </para>
            </entry>
          </row>
          <row>
            <entry command="item">
              <para>
                <code>
                  \huge
                </code>
              </para>
            </entry>
            <entry command="tab">
              <para>
                20.74
              </para>
            </entry>
            <entry command="tab">
              <para>
                20.74
              </para>
            </entry>
            <entry command="tab">
              <para>
                24.88
              </para>
            </entry>
          </row>
          <row>
            <entry command="item">
              <para>
                <code>
                  \Huge
                </code>
              </para>
            </entry>
            <entry command="tab">
              <para>
                24.88
              </para>
            </entry>
            <entry command="tab">
              <para>
                24.88
              </para>
            </entry>
            <entry command="tab">
              <para>
                24.88
              </para>
            </entry>
          </row>
        </tbody>
      </multitable>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="189">
          declaration form of font size commands
        </indexterm>
      </cindex>
      <para>
        The commands are listed here in declaration (not environment) form, since that is how they are typically used. For example.
      </para>
      <example endspaces=" ">
        <pre xml:space="preserve">
          \begin
Default handler: &lbrace;
          quotation
Default handler: &rbrace;
           \small The Tao that can be named is not the eternal Tao. \end
Default handler: &lbrace;
          quotation
Default handler: &rbrace;
        </pre>
      </example>
      <noindent/>
      <para>
        Here, the scope of the
        <code>
          \small
        </code>
         lasts until the end of the
        <code>
          quotation
        </code>
         environment. It would also end at the next type style command or the end of the current group, so you could enclose it in curly braces
        <codeDefault handler: &lbrace;
>
          \small This text is typeset in the small font.
Default handler: &rbrace;
        </code>
        .
      </para>
      <para>
        Trying to use these commands in math, as with
        <code>
          $\small mv^2/2$
        </code>
        , results in
        <samp>
          LaTeX Font Warning: Command \small invalid in math mode
        </samp>
        , and the font size doesn
Default handler: &textrsquo;
        t change. To work with a too-large formula, often the best option is to use the
        <code>
          displaymath
        </code>
         environment (
        <pxref label="Math-formulas">
          <xrefnodename>
            Math formulas
          </xrefnodename>
        </pxref>
        ), or one of the environments from the
        <code>
          amsmath
        </code>
         package. For inline mathematics, such as in a table of formulas, an alternative is something like
        <codeDefault handler: &lbrace;
>
          \small $mv^2/2$
Default handler: &rbrace;
        </code>
        . (Sometimes
        <code>
          \scriptsize
        </code>
         and
        <code>
          \scriptstyle
        </code>
         are confused. Both change the font size, but the latter also changes a number of other aspects of how mathematics is typeset.
        <xref label="Math-styles">
          <xrefnodename>
            Math styles
          </xrefnodename>
        </xref>
        .)
      </para>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="190">
          environment form of font size commands
        </indexterm>
      </cindex>
      <para>
        An
        <dfn>
          environment form
        </dfn>
         of each of these commands is also defined; for instance,
        <code>
          \begin
Default handler: &lbrace;
          tiny
Default handler: &rbrace;
          ...\end
Default handler: &lbrace;
          tiny
Default handler: &rbrace;
        </code>
        . However, in practice this form can easily lead to unwanted spaces at the beginning and/or end of the environment without careful consideration, so it
Default handler: &textrsquo;
        s generally less error-prone to stick to the declaration form.
      </para>
      <para>
        (Aside: Technically, due to the way
Default handler: &latex;
         defines
        <code>
          \begin
        </code>
         and
        <code>
          \end
        </code>
        , nearly every command that does not take an argument technically has an environment form. But in almost all cases, it would only cause confusion to use it. The reason for mentioning the environment form of the font size declarations specifically is that this particular use is not rare.)
      </para>
    </section>
    <node name="Low_002dlevel-font-commands" spaces=" ">
      <nodename>
        Low-level font commands
      </nodename>
      <nodeprev automatic="on">
        Font sizes
      </nodeprev>
      <nodeup automatic="on">
        Fonts
      </nodeup>
    </node>
    <section spaces=" ">
      <sectiontitle>
        Low-level font commands
      </sectiontitle>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="191">
          low-level font commands
        </indexterm>
      </cindex>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="192">
          font commands, low-level
        </indexterm>
      </cindex>
      <para>
        These commands are primarily intended for writers of macros and packages. The commands listed here are only a subset of the available ones.
Default handler: <!-- c xx but it should be complete -->
Default handler: <!-- c xx something about ultimately reading ENCFAM.fd? -->
      </para>
      <table commandarg="code" spaces=" " endspaces=" ">
        <beforefirstitem>
          <anchor name="low-level-font-commands-fontencoding">
            low level font commands fontencoding
          </anchor>
        </beforefirstitem>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                \fontencoding
Default handler: &lbrace;
                <var>
                  encoding
                </var>
Default handler: &rbrace;
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <findex index="fn" spaces=" ">
              <indexterm index="fn" number="154" mergedindex="cp">
                \fontencoding
              </indexterm>
            </findex>
            <para>
              Select the font encoding, the encoding of the output font. There are a large number of valid encodings. The most common are
              <code>
                OT1
              </code>
              , Knuth
Default handler: &textrsquo;
              s original encoding for Computer Modern (the default), and
              <code>
                T1
              </code>
              , also known as the Cork encoding, which has support for the accented characters used by the most widespread European languages (German, French, Italian, Polish and others), which allows
Default handler: &tex;
               to hyphenate words containing accented letters. For more, see
              <url>
                <urefurl>
                  https://ctan.org/pkg/encguide
                </urefurl>
              </url>
              .
            </para>
            <anchor name="low-level-font-commands-fontfamily">
              low level font commands fontfamily
            </anchor>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                \fontfamily
Default handler: &lbrace;
                <var>
                  family
                </var>
Default handler: &rbrace;
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <findex index="fn" spaces=" ">
              <indexterm index="fn" number="155" mergedindex="cp">
                \fontfamily
              </indexterm>
            </findex>
            <cindex index="cp" spaces=" ">
              <indexterm index="cp" number="193">
                families, of fonts
              </indexterm>
            </cindex>
            <cindex index="cp" spaces=" ">
              <indexterm index="cp" number="194">
                font catalogue
              </indexterm>
            </cindex>
            <para>
              Select the font family. The web page
              <url>
                <urefurl>
                  https://tug.org/FontCatalogue/
                </urefurl>
              </url>
               provides one way to browse through many of the fonts easily used with
Default handler: &latex;
              . Here are examples of some common families.
            </para>
            <multitable spaces=" " endspaces=" ">
              <columnprototypes>
                <columnprototype bracketed="on">
                  font
                </columnprototype>
                <columnprototype bracketed="on">
                  Computer Modern Typewriter more space
                </columnprototype>
              </columnprototypes>
              <tbody>
                <row>
                  <entry command="item">
                    <para>
                      <code>
                        pag
                      </code>
                    </para>
                  </entry>
                  <entry command="tab">
                    <para>
                      Avant Garde
                    </para>
                  </entry>
                </row>
                <row>
                  <entry command="item">
                    <para>
                      <code>
                        fvs
                      </code>
                    </para>
                  </entry>
                  <entry command="tab">
                    <para>
                      Bitstream Vera Sans
                    </para>
                  </entry>
                </row>
                <row>
                  <entry command="item">
                    <para>
                      <code>
                        pbk
                      </code>
                    </para>
                  </entry>
                  <entry command="tab">
                    <para>
                      Bookman
                    </para>
                  </entry>
                </row>
                <row>
                  <entry command="item">
                    <para>
                      <code>
                        bch
                      </code>
                    </para>
                  </entry>
                  <entry command="tab">
                    <para>
                      Charter
                    </para>
                  </entry>
                </row>
                <row>
                  <entry command="item">
                    <para>
                      <code>
                        ccr
                      </code>
                    </para>
                  </entry>
                  <entry command="tab">
                    <para>
                      Computer Concrete
                    </para>
                  </entry>
                </row>
                <row>
                  <entry command="item">
                    <para>
                      <code>
                        cmr
                      </code>
                    </para>
                  </entry>
                  <entry command="tab">
                    <para>
                      Computer Modern
                    </para>
                  </entry>
                </row>
                <row>
                  <entry command="item">
                    <para>
                      <code>
                        cmss
                      </code>
                    </para>
                  </entry>
                  <entry command="tab">
                    <para>
                      Computer Modern Sans Serif
                    </para>
                  </entry>
                </row>
                <row>
                  <entry command="item">
                    <para>
                      <code>
                        cmtt
                      </code>
                    </para>
                  </entry>
                  <entry command="tab">
                    <para>
                      Computer Modern Typewriter
                    </para>
                  </entry>
                </row>
                <row>
                  <entry command="item">
                    <para>
                      <code>
                        pcr
                      </code>
                    </para>
                  </entry>
                  <entry command="tab">
                    <para>
                      Courier
                    </para>
                  </entry>
                </row>
                <row>
                  <entry command="item">
                    <para>
                      <code>
                        phv
                      </code>
                    </para>
                  </entry>
                  <entry command="tab">
                    <para>
                      Helvetica
                    </para>
                  </entry>
                </row>
                <row>
                  <entry command="item">
                    <para>
                      <code>
                        fi4
                      </code>
                    </para>
                  </entry>
                  <entry command="tab">
                    <para>
                      Inconsolata
                    </para>
                  </entry>
                </row>
                <row>
                  <entry command="item">
                    <para>
                      <code>
                        lmr
                      </code>
                    </para>
                  </entry>
                  <entry command="tab">
                    <para>
                      Latin Modern
                    </para>
                  </entry>
                </row>
                <row>
                  <entry command="item">
                    <para>
                      <code>
                        lmss
                      </code>
                    </para>
                  </entry>
                  <entry command="tab">
                    <para>
                      Latin Modern Sans
                    </para>
                  </entry>
                </row>
                <row>
                  <entry command="item">
                    <para>
                      <code>
                        lmtt
                      </code>
                    </para>
                  </entry>
                  <entry command="tab">
                    <para>
                      Latin Modern Typewriter
                    </para>
                  </entry>
                </row>
                <row>
                  <entry command="item">
                    <para>
                      <code>
                        pnc
                      </code>
                    </para>
                  </entry>
                  <entry command="tab">
                    <para>
                      New Century Schoolbook
                    </para>
                  </entry>
                </row>
                <row>
                  <entry command="item">
                    <para>
                      <code>
                        ppl
                      </code>
                    </para>
                  </entry>
                  <entry command="tab">
                    <para>
                      Palatino
                    </para>
                  </entry>
                </row>
                <row>
                  <entry command="item">
                    <para>
                      <code>
                        ptm
                      </code>
                    </para>
                  </entry>
                  <entry command="tab">
                    <para>
                      Times
                    </para>
                  </entry>
                </row>
                <row>
                  <entry command="item">
                    <para>
                      <code>
                        uncl
                      </code>
                    </para>
                  </entry>
                  <entry command="tab">
                    <para>
                      Uncial
                    </para>
                  </entry>
                </row>
                <row>
                  <entry command="item">
                    <para>
                      <code>
                        put
                      </code>
                    </para>
                  </entry>
                  <entry command="tab">
                    <para>
                      Utopia
                    </para>
                  </entry>
                </row>
                <row>
                  <entry command="item">
                    <para>
                      <code>
                        pzc
                      </code>
                    </para>
                  </entry>
                  <entry command="tab">
                    <para>
                      Zapf Chancery
                    </para>
                  </entry>
                </row>
              </tbody>
            </multitable>
            <anchor name="low-level-font-commands-fontseries">
              low level font commands fontseries
            </anchor>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                \fontseries
Default handler: &lbrace;
                <var>
                  series
                </var>
Default handler: &rbrace;
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <findex index="fn" spaces=" ">
              <indexterm index="fn" number="156" mergedindex="cp">
                \fontseries
              </indexterm>
            </findex>
            <cindex index="cp" spaces=" ">
              <indexterm index="cp" number="195">
                series, of fonts
              </indexterm>
            </cindex>
            <para>
              Select the font series. A
              <dfn>
                series
              </dfn>
               combines a
              <dfn>
                weight
              </dfn>
               and a
              <dfn>
                width
              </dfn>
              . Typically, a font supports only a few of the possible combinations. Some common combined series values include:
            </para>
            <multitable spaces=" " endspaces=" ">
              <columnprototypes>
                <columnprototype bracketed="on">
                  xx
                </columnprototype>
                <columnprototype bracketed="on">
                  Medium (normal)xx
                </columnprototype>
              </columnprototypes>
              <tbody>
                <row>
                  <entry command="item">
                    <para>
                      <code>
                        m
                      </code>
                    </para>
                  </entry>
                  <entry command="tab">
                    <para>
                      Medium (normal)
                    </para>
                  </entry>
                </row>
                <row>
                  <entry command="item">
                    <para>
                      <code>
                        b
                      </code>
                    </para>
                  </entry>
                  <entry command="tab">
                    <para>
                      Bold
                    </para>
                  </entry>
                </row>
                <row>
                  <entry command="item">
                    <para>
                      <code>
                        c
                      </code>
                    </para>
                  </entry>
                  <entry command="tab">
                    <para>
                      Condensed
                    </para>
                  </entry>
                </row>
                <row>
                  <entry command="item">
                    <para>
                      <code>
                        bc
                      </code>
                    </para>
                  </entry>
                  <entry command="tab">
                    <para>
                      Bold condensed
                    </para>
                  </entry>
                </row>
                <row>
                  <entry command="item">
                    <para>
                      <code>
                        bx
                      </code>
                    </para>
                  </entry>
                  <entry command="tab">
                    <para>
                      Bold extended
                    </para>
                  </entry>
                </row>
              </tbody>
            </multitable>
            <cindex index="cp" spaces=" ">
              <indexterm index="cp" number="196">
                weights, of fonts
              </indexterm>
            </cindex>
            <para>
              The possible values for weight, individually, are:
            </para>
            <multitable spaces=" " endspaces=" ">
              <columnprototypes>
                <columnprototype bracketed="on">
                  xx
                </columnprototype>
                <columnprototype bracketed="on">
                  Medium (normal) xx
                </columnprototype>
              </columnprototypes>
              <tbody>
                <row>
                  <entry command="item">
                    <para>
                      <code>
                        ul
                      </code>
                    </para>
                  </entry>
                  <entry command="tab">
                    <para>
                      Ultra light
                    </para>
                  </entry>
                </row>
                <row>
                  <entry command="item">
                    <para>
                      <code>
                        el
                      </code>
                    </para>
                  </entry>
                  <entry command="tab">
                    <para>
                      Extra light
                    </para>
                  </entry>
                </row>
                <row>
                  <entry command="item">
                    <para>
                      <code>
                        l
                      </code>
                    </para>
                  </entry>
                  <entry command="tab">
                    <para>
                      Light
                    </para>
                  </entry>
                </row>
                <row>
                  <entry command="item">
                    <para>
                      <code>
                        sl
                      </code>
                    </para>
                  </entry>
                  <entry command="tab">
                    <para>
                      Semi light
                    </para>
                  </entry>
                </row>
                <row>
                  <entry command="item">
                    <para>
                      <code>
                        m
                      </code>
                    </para>
                  </entry>
                  <entry command="tab">
                    <para>
                      Medium (normal)
                    </para>
                  </entry>
                </row>
                <row>
                  <entry command="item">
                    <para>
                      <code>
                        sb
                      </code>
                    </para>
                  </entry>
                  <entry command="tab">
                    <para>
                      Semi bold
                    </para>
                  </entry>
                </row>
                <row>
                  <entry command="item">
                    <para>
                      <code>
                        b
                      </code>
                    </para>
                  </entry>
                  <entry command="tab">
                    <para>
                      Bold
                    </para>
                  </entry>
                </row>
                <row>
                  <entry command="item">
                    <para>
                      <code>
                        eb
                      </code>
                    </para>
                  </entry>
                  <entry command="tab">
                    <para>
                      Extra bold
                    </para>
                  </entry>
                </row>
                <row>
                  <entry command="item">
                    <para>
                      <code>
                        ub
                      </code>
                    </para>
                  </entry>
                  <entry command="tab">
                    <para>
                      Ultra bold
                    </para>
                  </entry>
                </row>
              </tbody>
            </multitable>
            <cindex index="cp" spaces=" ">
              <indexterm index="cp" number="197">
                widths, of fonts
              </indexterm>
            </cindex>
            <para>
              The possible values for width, individually, are (the meaning and relationship of these terms varies with individual typefaces):
            </para>
            <multitable spaces=" " endspaces=" ">
              <columnprototypes>
                <columnprototype bracketed="on">
                  xx
                </columnprototype>
                <columnprototype bracketed="on">
                  Ultra condensed
                </columnprototype>
              </columnprototypes>
              <tbody>
                <row>
                  <entry command="item">
                    <para>
                      <code>
                        uc
                      </code>
                    </para>
                  </entry>
                  <entry command="tab">
                    <para>
                      Ultra condensed
                    </para>
                  </entry>
                </row>
                <row>
                  <entry command="item">
                    <para>
                      <code>
                        ec
                      </code>
                    </para>
                  </entry>
                  <entry command="tab">
                    <para>
                      Extra condensed
                    </para>
                  </entry>
                </row>
                <row>
                  <entry command="item">
                    <para>
                      <code>
                        c
                      </code>
                    </para>
                  </entry>
                  <entry command="tab">
                    <para>
                      Condensed
                    </para>
                  </entry>
                </row>
                <row>
                  <entry command="item">
                    <para>
                      <code>
                        sc
                      </code>
                    </para>
                  </entry>
                  <entry command="tab">
                    <para>
                      Semi condensed
                    </para>
                  </entry>
                </row>
                <row>
                  <entry command="item">
                    <para>
                      <code>
                        m
                      </code>
                    </para>
                  </entry>
                  <entry command="tab">
                    <para>
                      Medium
                    </para>
                  </entry>
                </row>
                <row>
                  <entry command="item">
                    <para>
                      <code>
                        sx
                      </code>
                    </para>
                  </entry>
                  <entry command="tab">
                    <para>
                      Semi expanded
                    </para>
                  </entry>
                </row>
                <row>
                  <entry command="item">
                    <para>
                      <code>
                        x
                      </code>
                    </para>
                  </entry>
                  <entry command="tab">
                    <para>
                      Expanded
                    </para>
                  </entry>
                </row>
                <row>
                  <entry command="item">
                    <para>
                      <code>
                        ex
                      </code>
                    </para>
                  </entry>
                  <entry command="tab">
                    <para>
                      Extra expanded
                    </para>
                  </entry>
                </row>
                <row>
                  <entry command="item">
                    <para>
                      <code>
                        ux
                      </code>
                    </para>
                  </entry>
                  <entry command="tab">
                    <para>
                      Ultra expanded
                    </para>
                  </entry>
                </row>
              </tbody>
            </multitable>
            <para>
              When forming the
              <var>
                series
              </var>
               string from the weight and width, drop the
              <code>
                m
              </code>
               that stands for medium weight or medium width, unless both weight and width are
              <code>
                m
              </code>
              , in which case use just one (
              <samp>
                <code>
                  m
                </code>
              </samp>
              ).
            </para>
            <anchor name="low-level-font-commands-fontshape">
              low level font commands fontshape
            </anchor>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                \fontshape
Default handler: &lbrace;
                <var>
                  shape
                </var>
Default handler: &rbrace;
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <findex index="fn" spaces=" ">
              <indexterm index="fn" number="157" mergedindex="cp">
                \fontshape
              </indexterm>
            </findex>
            <cindex index="cp" spaces=" ">
              <indexterm index="cp" number="198">
                shapes, of fonts
              </indexterm>
            </cindex>
            <para>
              Select font shape. Valid shapes are:
            </para>
            <multitable spaces=" " endspaces=" ">
              <columnprototypes>
                <columnprototype bracketed="on">
                  xx
                </columnprototype>
                <columnprototype bracketed="on">
                  Slanted (oblique)xx
                </columnprototype>
              </columnprototypes>
              <tbody>
                <row>
                  <entry command="item">
                    <para>
                      <code>
                        n
                      </code>
                    </para>
                  </entry>
                  <entry command="tab">
                    <para>
                      Upright (normal)
                    </para>
                  </entry>
                </row>
                <row>
                  <entry command="item">
                    <para>
                      <code>
                        it
                      </code>
                    </para>
                  </entry>
                  <entry command="tab">
                    <para>
                      Italic
                    </para>
                  </entry>
                </row>
                <row>
                  <entry command="item">
                    <para>
                      <code>
                        sl
                      </code>
                    </para>
                  </entry>
                  <entry command="tab">
                    <para>
                      Slanted (oblique)
                    </para>
                  </entry>
                </row>
                <row>
                  <entry command="item">
                    <para>
                      <code>
                        sc
                      </code>
                    </para>
                  </entry>
                  <entry command="tab">
                    <para>
                      Small caps
                    </para>
                  </entry>
                </row>
                <row>
                  <entry command="item">
                    <para>
                      <code>
                        ui
                      </code>
                    </para>
                  </entry>
                  <entry command="tab">
                    <para>
                      Upright italics
                    </para>
                  </entry>
                </row>
                <row>
                  <entry command="item">
                    <para>
                      <code>
                        ol
                      </code>
                    </para>
                  </entry>
                  <entry command="tab">
                    <para>
                      Outline
                    </para>
                  </entry>
                </row>
              </tbody>
            </multitable>
            <para>
              The two last shapes are not available for most font families, and small caps are often missing as well.
            </para>
            <anchor name="low-level-font-commands-fontsize">
              low level font commands fontsize
            </anchor>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                \fontsize
Default handler: &lbrace;
                <var>
                  size
                </var>
Default handler: &rbrace;
Default handler: &lbrace;
                <var>
                  skip
                </var>
Default handler: &rbrace;
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <findex index="fn" spaces=" ">
              <indexterm index="fn" number="158" mergedindex="cp">
                \fontsize
              </indexterm>
            </findex>
            <cindex index="cp" spaces=" ">
              <indexterm index="cp" number="199">
                font size
              </indexterm>
            </cindex>
            <findex index="fn" spaces=" ">
              <indexterm index="fn" number="159" mergedindex="cp">
                \baselineskip
              </indexterm>
            </findex>
            <para>
              Set the font size and the line spacing. The unit of both parameters defaults to points (
              <code>
                pt
              </code>
              ). The line spacing is the nominal vertical space between lines, baseline to baseline. It is stored in the parameter
              <code>
                \baselineskip
              </code>
              . The default
              <code>
                \baselineskip
              </code>
               for the Computer Modern typeface is 1.2 times the
              <code>
                \fontsize
              </code>
              . Changing
              <code>
                \baselineskip
              </code>
               directly is inadvisable since its value is reset every time a size change happens; instead use
              <code>
                \baselinestretch
              </code>
              . (
              <pxref label="_005cbaselineskip-_0026-_005cbaselinestretch">
                <xrefnodename>
                  \baselineskip
                  &
                   \baselinestretch
                </xrefnodename>
              </pxref>
              ).
            </para>
            <anchor name="low-level-font-commands-linespread">
              low level font commands linespread
            </anchor>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                \linespread
Default handler: &lbrace;
                <var>
                  factor
                </var>
Default handler: &rbrace;
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <findex index="fn" spaces=" ">
              <indexterm index="fn" number="160" mergedindex="cp">
                \linespread
              </indexterm>
            </findex>
            <para>
              Equivalent to
              <code>
                \renewcommand
Default handler: &lbrace;
                \baselinestretch
Default handler: &rbrace;
Default handler: &lbrace;
                <var>
                  factor
                </var>
Default handler: &rbrace;
              </code>
              , and therefore must be followed by
              <code>
                \selectfont
              </code>
               to have any effect. Best specified in the preamble.
              <xref label="_005cbaselineskip-_0026-_005cbaselinestretch">
                <xrefnodename>
                  \baselineskip
                  &
                   \baselinestretch
                </xrefnodename>
              </xref>
              , for using
              <code>
                setspace
              </code>
               package instead.
            </para>
            <anchor name="low-level-font-commands-selectfont">
              low level font commands selectfont
            </anchor>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                \selectfont
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <findex index="fn" spaces=" ">
              <indexterm index="fn" number="161" mergedindex="cp">
                \selectfont
              </indexterm>
            </findex>
            <para>
              The effects of the font commands described above do not happen until
              <code>
                \selectfont
              </code>
               is called, as in
              <code>
                \fontfamily
Default handler: &lbrace;
                <var>
                  familyname
                </var>
Default handler: &rbrace;
                \selectfont
              </code>
              . It is often useful to put this in a macro:
Default handler: &linebreak;
              <code>
                \newcommand*
Default handler: &lbrace;
                \myfont
Default handler: &rbrace;
Default handler: &lbrace;
                \fontfamily
Default handler: &lbrace;
                <var>
                  familyname
                </var>
Default handler: &rbrace;
                \selectfont
Default handler: &rbrace;
              </code>
Default handler: &linebreak;
               (
              <pxref label="_005cnewcommand-_0026-_005crenewcommand">
                <xrefnodename>
                  \newcommand
                  &
                   \renewcommand
                </xrefnodename>
              </pxref>
              ).
            </para>
            <anchor name="low-level-font-commands-usefont">
              low level font commands usefont
            </anchor>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                \usefont
Default handler: &lbrace;
                <var>
                  enc
                </var>
Default handler: &rbrace;
Default handler: &lbrace;
                <var>
                  family
                </var>
Default handler: &rbrace;
Default handler: &lbrace;
                <var>
                  series
                </var>
Default handler: &rbrace;
Default handler: &lbrace;
                <var>
                  shape
                </var>
Default handler: &rbrace;
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <findex index="fn" spaces=" ">
              <indexterm index="fn" number="162" mergedindex="cp">
                \usefont
              </indexterm>
            </findex>
            <para>
              The same as invoking
              <code>
                \fontencoding
              </code>
              ,
              <code>
                \fontfamily
              </code>
              ,
              <code>
                \fontseries
              </code>
               and
              <code>
                \fontshape
              </code>
               with the given parameters, followed by
              <code>
                \selectfont
              </code>
              . For example:
            </para>
            <example endspaces=" ">
              <pre xml:space="preserve">
                \usefont
Default handler: &lbrace;
                ot1
Default handler: &rbrace;
Default handler: &lbrace;
                cmr
Default handler: &rbrace;
Default handler: &lbrace;
                m
Default handler: &rbrace;
Default handler: &lbrace;
                n
Default handler: &rbrace;
              </pre>
            </example>
          </tableitem>
        </tableentry>
      </table>
    </section>
  </chapter>
  <node name="Layout" spaces=" ">
    <nodename>
      Layout
    </nodename>
    <nodenext automatic="on">
      Sectioning
    </nodenext>
    <nodeprev automatic="on">
      Fonts
    </nodeprev>
    <nodeup automatic="on">
      Top
    </nodeup>
  </node>
  <chapter spaces=" ">
    <sectiontitle>
      Layout
    </sectiontitle>
    <cindex index="cp" spaces=" ">
      <indexterm index="cp" number="200">
        layout commands
      </indexterm>
    </cindex>
    <para>
      Commands for controlling the general page layout.
    </para>
    <menu endspaces=" ">
      <menuentry>
        <menuleadingtext>
          *
        </menuleadingtext>
        <menunode>
          \onecolumn
        </menunode>
        <menuseparator>
          ::
        </menuseparator>
        <menudescription>
          <pre xml:space="preserve">
            Use one-column layout.
          </pre>
        </menudescription>
      </menuentry>
      <menuentry>
        <menuleadingtext>
          *
        </menuleadingtext>
        <menunode>
          \twocolumn
        </menunode>
        <menuseparator>
          ::
        </menuseparator>
        <menudescription>
          <pre xml:space="preserve">
            Use two-column layout.
          </pre>
        </menudescription>
      </menuentry>
      <menuentry>
        <menuleadingtext>
          *
        </menuleadingtext>
        <menunode>
          \flushbottom
        </menunode>
        <menuseparator>
          ::
        </menuseparator>
        <menudescription>
          <pre xml:space="preserve">
            Make all text pages the same height.
          </pre>
        </menudescription>
      </menuentry>
      <menuentry>
        <menuleadingtext>
          *
        </menuleadingtext>
        <menunode>
          \raggedbottom
        </menunode>
        <menuseparator>
          ::
        </menuseparator>
        <menudescription>
          <pre xml:space="preserve">
            Allow text pages of differing height.
          </pre>
        </menudescription>
      </menuentry>
      <menuentry>
        <menuleadingtext>
          *
        </menuleadingtext>
        <menunode>
          Page layout parameters
        </menunode>
        <menuseparator>
          ::
        </menuseparator>
        <menudescription>
          <pre xml:space="preserve">
            <code>
              \headheight
            </code>
            <code>
              \footskip
            </code>
            .
          </pre>
        </menudescription>
      </menuentry>
      <menuentry>
        <menuleadingtext>
          *
        </menuleadingtext>
        <menunode>
          \baselineskip
          &
           \baselinestretch
        </menunode>
        <menuseparator>
          ::
        </menuseparator>
        <menudescription>
          <pre xml:space="preserve">
            Space between lines.
          </pre>
        </menudescription>
      </menuentry>
      <menuentry>
        <menuleadingtext>
          *
        </menuleadingtext>
        <menunode>
          Floats
        </menunode>
        <menuseparator>
          ::
        </menuseparator>
        <menudescription>
          <pre xml:space="preserve">
            Figures, tables, etc.
          </pre>
        </menudescription>
      </menuentry>
    </menu>
    <node name="_005conecolumn" spaces=" ">
      <nodename>
        \onecolumn
      </nodename>
      <nodenext automatic="on">
        \twocolumn
      </nodenext>
      <nodeup automatic="on">
        Layout
      </nodeup>
    </node>
    <section spaces=" ">
      <sectiontitle>
        <code>
          \onecolumn
        </code>
      </sectiontitle>
      <findex index="fn" spaces=" ">
        <indexterm index="fn" number="163" mergedindex="cp">
          \onecolumn
        </indexterm>
      </findex>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="201">
          one-column output
        </indexterm>
      </cindex>
      <para>
        Synopsis:
      </para>
      <example endspaces=" ">
        <pre xml:space="preserve">
          \onecolumn
        </pre>
      </example>
      <para>
        Start a new page and produce single-column output. If the document is given the class option
        <code>
          onecolumn
        </code>
         then this is the default behavior (
        <pxref label="Document-class-options">
          <xrefnodename>
            Document class options
          </xrefnodename>
        </pxref>
        ). This command is fragile (
        <pxref label="_005cprotect">
          <xrefnodename>
            \protect
          </xrefnodename>
        </pxref>
        ).
      </para>
    </section>
    <node name="_005ctwocolumn" spaces=" ">
      <nodename>
        \twocolumn
      </nodename>
      <nodenext automatic="on">
        \flushbottom
      </nodenext>
      <nodeprev automatic="on">
        \onecolumn
      </nodeprev>
      <nodeup automatic="on">
        Layout
      </nodeup>
    </node>
    <section spaces=" ">
      <sectiontitle>
        <code>
          \twocolumn
        </code>
      </sectiontitle>
      <findex index="fn" spaces=" ">
        <indexterm index="fn" number="164" mergedindex="cp">
          \twocolumn
        </indexterm>
      </findex>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="202">
          multicolumn text
        </indexterm>
      </cindex>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="203">
          two-column output
        </indexterm>
      </cindex>
      <para>
        Synopses:
      </para>
      <example endspaces=" ">
        <pre xml:space="preserve">
          \twocolumn \twocolumn[
          <var>
            prelim one column text
          </var>
          ]
        </pre>
      </example>
      <para>
        Start a new page and produce two-column output. If the document is given the class option
        <code>
          twocolumn
        </code>
         then this is the default (
        <pxref label="Document-class-options">
          <xrefnodename>
            Document class options
          </xrefnodename>
        </pxref>
        ). This command is fragile (
        <pxref label="_005cprotect">
          <xrefnodename>
            \protect
          </xrefnodename>
        </pxref>
        ).
      </para>
      <para>
        If the optional
        <var>
          prelim one column text
        </var>
         argument is present, it is typeset in one-column mode before the two-column typesetting starts.
      </para>
      <para>
        These parameters control typesetting in two-column output:
      </para>
      <ftable commandarg="code" spaces=" " endspaces=" ">
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                <indexterm index="fn" number="165" mergedindex="cp">
                  \columnsep
                </indexterm>
                \columnsep
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <anchor name="twocolumn-columnsep">
              twocolumn columnsep
            </anchor>
            <para>
              The distance between columns. The default is 35pt. Change it with a command such as
              <code>
                \setlength
Default handler: &lbrace;
                \columnsep
Default handler: &rbrace;
Default handler: &lbrace;
                40pt
Default handler: &rbrace;
              </code>
              . You must change it before the two column mode starts; in the preamble is a good place.
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                <indexterm index="fn" number="166" mergedindex="cp">
                  \columnseprule
                </indexterm>
                \columnseprule
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <anchor name="twocolumn-columnseprule">
              twocolumn columnseprule
            </anchor>
            <para>
              The width of the rule between columns. The default is 0pt, meaning that there is no rule. Otherwise, the rule appears halfway between the two columns. Change it with a command such as
              <code>
                \setlength
Default handler: &lbrace;
                \columnseprule
Default handler: &rbrace;
Default handler: &lbrace;
                0.4pt
Default handler: &rbrace;
              </code>
              , before the two-column mode starts.
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                <indexterm index="fn" number="167" mergedindex="cp">
                  \columnwidth
                </indexterm>
                \columnwidth
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <anchor name="twocolumn-columnwidth">
              twocolumn columnwidth
            </anchor>
            <para>
              The width of a single column. In one-column mode this is equal to
              <code>
                \textwidth
              </code>
              . In two-column mode by default
Default handler: &latex;
               sets the width of each of the two columns,
              <code>
                \columnwidth
              </code>
              , to be half of
              <code>
                \textwidth
              </code>
               minus
              <code>
                \columnsep
              </code>
              .
            </para>
          </tableitem>
        </tableentry>
      </ftable>
      <para>
        In a two-column document, the starred environments
        <code>
          table*
        </code>
         and
        <code>
          figure*
        </code>
         are two columns wide, whereas the unstarred environments
        <code>
          table
        </code>
         and
        <code>
          figure
        </code>
         take up only one column (
        <pxref label="figure">
          <xrefnodename>
            figure
          </xrefnodename>
        </pxref>
         and
        <pxref label="table">
          <xrefnodename>
            table
          </xrefnodename>
        </pxref>
        ).
Default handler: &latex;
         places starred floats at the top of a page. The following parameters control float behavior of two-column output.
      </para>
      <ftable commandarg="code" spaces=" " endspaces=" ">
        <beforefirstitem>
          <anchor name="twocolumn-dbltopfraction">
            twocolumn dbltopfraction
          </anchor>
        </beforefirstitem>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                <indexterm index="fn" number="168" mergedindex="cp">
                  \dbltopfraction
                </indexterm>
                \dbltopfraction
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <para>
              The maximum fraction at the top of a two-column page that may be occupied by two-column wide floats. The default is 0.7, meaning that the height of a
              <code>
                table*
              </code>
               or
              <code>
                figure*
              </code>
               environment must not exceed
              <code>
                0.7\textheight
              </code>
              . If the height of your starred float environment exceeds this then you can take one of the following actions to prevent it from floating all the way to the back of the document:
            </para>
            <itemize commandarg="bullet" spaces=" " endspaces=" ">
              <itemprepend>
                <formattingcommand command="bullet"/>
              </itemprepend>
              <listitem>
                <prependDefault handler: &bullet;
/>
                <para>
                  Use the
                  <code>
                    [tp]
                  </code>
                   location specifier to tell
Default handler: &latex;
                   to try to put the bulky float on a page by itself, as well as at the top of a page.
                </para>
              </listitem>
              <listitem>
                <prependDefault handler: &bullet;
/>
                <para>
                  Use the
                  <code>
                    [t!]
                  </code>
                   location specifier to override the effect of
                  <code>
                    \dbltopfraction
                  </code>
                   for this particular float.
                </para>
              </listitem>
              <listitem>
                <prependDefault handler: &bullet;
/>
                <para>
                  Increase the value of
                  <code>
                    \dbltopfraction
                  </code>
                   to a suitably large number, to avoid going to float pages so soon.
                </para>
              </listitem>
            </itemize>
            <para>
              You can redefine it, as with
              <code>
                \renewcommand
Default handler: &lbrace;
                \dbltopfraction
Default handler: &rbrace;
Default handler: &lbrace;
                0.9
Default handler: &rbrace;
              </code>
              .
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                <indexterm index="fn" number="169" mergedindex="cp">
                  \dblfloatpagefraction
                </indexterm>
                \dblfloatpagefraction
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <anchor name="twocolumn-dblfloatpagefraction">
              twocolumn dblfloatpagefraction
            </anchor>
            <para>
              For a float page of two-column wide floats, this is the minimum fraction that must be occupied by floats, limiting the amount of blank space.
Default handler: &latex;
Default handler: &textrsquo;
              s default is
              <code>
                0.5
              </code>
              . Change it with
              <code>
                \renewcommand
              </code>
              .
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                <indexterm index="fn" number="170" mergedindex="cp">
                  \dblfloatsep
                </indexterm>
                \dblfloatsep
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <anchor name="twocolumn-dblfloatsep">
              twocolumn dblfloatsep
            </anchor>
            <para>
              On a float page of two-column wide floats, this length is the distance between floats, at both the top and bottom of the page. The default is
              <code>
                12pt plus2pt minus2pt
              </code>
               for a document set at
              <code>
                10pt
              </code>
               or
              <code>
                11pt
              </code>
              , and
              <code>
                14pt plus2pt minus4pt
              </code>
               for a document set at
              <code>
                12pt
              </code>
              .
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                <indexterm index="fn" number="171" mergedindex="cp">
                  \dbltextfloatsep
                </indexterm>
                \dbltextfloatsep
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <anchor name="twocolumn-dbltextfloatsep">
              twocolumn dbltextfloatsep
            </anchor>
            <para>
              This length is the distance between a multi-column float at the top or bottom of a page and the main text. The default is
              <code>
                20pt plus2pt minus4pt
              </code>
              .
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                <indexterm index="fn" number="172" mergedindex="cp">
                  \dbltopnumber
                </indexterm>
                \dbltopnumber
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <anchor name="twocolumn-dbltopnumber">
              twocolumn dbltopnumber
            </anchor>
            <para>
              On a float page of two-column wide floats, this counter gives the maximum number of floats allowed at the top of the page. The
Default handler: &latex;
               default is
              <code>
                2
              </code>
              .
            </para>
          </tableitem>
        </tableentry>
      </ftable>
Default handler: <!-- c From egreg at http://tex.stackexchange.com/a/142232/339 -->
      <para>
        This example uses
        <code>
          \twocolumn
        </code>
Default handler: &textrsquo;
        s optional argument of to create a title that spans the two-column article:
      </para>
      <example endspaces=" ">
        <pre xml:space="preserve">
          \documentclass[twocolumn]
Default handler: &lbrace;
          article
Default handler: &rbrace;
           \newcommand
Default handler: &lbrace;
          \authormark
Default handler: &rbrace;
          [1]
Default handler: &lbrace;
          \textsuperscript
Default handler: &lbrace;
          #1
Default handler: &rbrace;
Default handler: &rbrace;
           \begin
Default handler: &lbrace;
          document
Default handler: &rbrace;
           \twocolumn[
Default handler: &lbrace;
          % inside this optional argument goes one-column text \centering \LARGE The Title \\[1.5em] \large Author One\authormark
Default handler: &lbrace;
          1
Default handler: &rbrace;
          , Author Two\authormark
Default handler: &lbrace;
          2
Default handler: &rbrace;
          , Author Three\authormark
Default handler: &lbrace;
          1
Default handler: &rbrace;
           \\[1em] \normalsize \begin
Default handler: &lbrace;
          tabular
Default handler: &rbrace;
Default handler: &lbrace;
          p
Default handler: &lbrace;
          .2\textwidth
Default handler: &rbrace;
Default handler: &arobase;
Default handler: &lbrace;
          \hspace
Default handler: &lbrace;
          2em
Default handler: &rbrace;
Default handler: &rbrace;
          p
Default handler: &lbrace;
          .2\textwidth
Default handler: &rbrace;
Default handler: &rbrace;
           \authormark
Default handler: &lbrace;
          1
Default handler: &rbrace;
          Department one
          &
          \authormark
Default handler: &lbrace;
          2
Default handler: &rbrace;
          Department two \\ School one
          &
          School two \end
Default handler: &lbrace;
          tabular
Default handler: &rbrace;
          \\[3em] % space below title part
Default handler: &rbrace;
          ] Two column text here.
        </pre>
      </example>
    </section>
    <node name="_005cflushbottom" spaces=" ">
      <nodename>
        \flushbottom
      </nodename>
      <nodenext automatic="on">
        \raggedbottom
      </nodenext>
      <nodeprev automatic="on">
        \twocolumn
      </nodeprev>
      <nodeup automatic="on">
        Layout
      </nodeup>
    </node>
    <section spaces=" ">
      <sectiontitle>
        <code>
          \flushbottom
        </code>
      </sectiontitle>
      <findex index="fn" spaces=" ">
        <indexterm index="fn" number="173" mergedindex="cp">
          \flushbottom
        </indexterm>
      </findex>
      <para>
        Make all pages in the document after this declaration have the same height, by stretching the vertical space where necessary to fill out the page. This is most often used when making two-sided documents since the differences in facing pages can be glaring.
      </para>
      <para>
        If
Default handler: &tex;
         cannot satisfactorily stretch the vertical space in a page then you get a message like
        <samp>
          Underfull \vbox (badness 10000) has occurred while \output is active
        </samp>
        . If you get that, one option is to change to
        <code>
          \raggedbottom
        </code>
         (
        <pxref label="_005craggedbottom">
          <xrefnodename>
            \raggedbottom
          </xrefnodename>
        </pxref>
        ). Alternatively, you can adjust the
        <code>
          textheight
        </code>
         to make compatible pages, or you can add some vertical stretch glue between lines or between paragraphs, as in
        <code>
          \setlength
Default handler: &lbrace;
          \parskip
Default handler: &rbrace;
Default handler: &lbrace;
          0ex plus0.1ex
Default handler: &rbrace;
        </code>
        . Your last option is to, in a final editing stage, adjust the height of individual pages (
        <pxref label="_005cenlargethispage">
          <xrefnodename>
            \enlargethispage
          </xrefnodename>
        </pxref>
        ).
      </para>
      <para>
        The
        <code>
          \flushbottom
        </code>
         state is the default only if you select the
        <code>
          twocolumn
        </code>
         document class option (
        <pxref label="Document-class-options">
          <xrefnodename>
            Document class options
          </xrefnodename>
        </pxref>
        ), and for indexes made using
        <code>
          makeidx
        </code>
        .
      </para>
    </section>
    <node name="_005craggedbottom" spaces=" ">
      <nodename>
        \raggedbottom
      </nodename>
      <nodenext automatic="on">
        Page layout parameters
      </nodenext>
      <nodeprev automatic="on">
        \flushbottom
      </nodeprev>
      <nodeup automatic="on">
        Layout
      </nodeup>
    </node>
    <section spaces=" ">
      <sectiontitle>
        <code>
          \raggedbottom
        </code>
      </sectiontitle>
      <findex index="fn" spaces=" ">
        <indexterm index="fn" number="174" mergedindex="cp">
          \raggedbottom
        </indexterm>
      </findex>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="204">
          stretch, omitting vertical
        </indexterm>
      </cindex>
      <para>
        Make all later pages the natural height of the material on that page; no rubber vertical lengths will be stretched. Thus, in a two-sided document the facing pages may be different heights. This command can go at any point in the document body.
        <xref label="_005cflushbottom">
          <xrefnodename>
            \flushbottom
          </xrefnodename>
        </xref>
        .
      </para>
      <para>
        This is the default unless you select the
        <code>
          twocolumn
        </code>
         document class option (
        <pxref label="Document-class-options">
          <xrefnodename>
            Document class options
          </xrefnodename>
        </pxref>
        ).
      </para>
    </section>
    <node name="Page-layout-parameters" spaces=" ">
      <nodename>
        Page layout parameters
      </nodename>
      <nodenext automatic="on">
        \baselineskip
        &
         \baselinestretch
      </nodenext>
      <nodeprev automatic="on">
        \raggedbottom
      </nodeprev>
      <nodeup automatic="on">
        Layout
      </nodeup>
    </node>
    <section spaces=" ">
      <sectiontitle>
        Page layout parameters
      </sectiontitle>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="205">
          page layout parameters
        </indexterm>
      </cindex>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="206">
          parameters, page layout
        </indexterm>
      </cindex>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="207">
          layout, page parameters for
        </indexterm>
      </cindex>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="208">
          header, parameters for
        </indexterm>
      </cindex>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="209">
          footer, parameters for
        </indexterm>
      </cindex>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="210">
          running header and footer
        </indexterm>
      </cindex>
      <ftable commandarg="code" spaces=" " endspaces=" ">
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                <indexterm index="fn" number="175" mergedindex="cp">
                  \columnsep
                </indexterm>
                \columnsep
              </itemformat>
            </item>
            <itemx spaces=" ">
              <itemformat command="code">
                <indexterm index="fn" number="176" mergedindex="cp">
                  \columnseprule
                </indexterm>
                \columnseprule
              </itemformat>
            </itemx>
            <itemx spaces=" ">
              <itemformat command="code">
                <indexterm index="fn" number="177" mergedindex="cp">
                  \columnwidth
                </indexterm>
                \columnwidth
              </itemformat>
            </itemx>
          </tableterm>
          <tableitem>
            <findex index="fn" spaces=" ">
              <indexterm index="fn" number="178" mergedindex="cp">
                \columnsep
              </indexterm>
            </findex>
            <findex index="fn" spaces=" ">
              <indexterm index="fn" number="179" mergedindex="cp">
                \columnseprule
              </indexterm>
            </findex>
            <findex index="fn" spaces=" ">
              <indexterm index="fn" number="180" mergedindex="cp">
                \columnwidth
              </indexterm>
            </findex>
            <anchor name="page-layout-parameters-columnsep">
              page layout parameters columnsep
            </anchor>
            <anchor name="page-layout-parameters-columnseprule">
              page layout parameters columnseprule
            </anchor>
            <anchor name="page-layout-parameters-columnwidth">
              page layout parameters columnwidth
            </anchor>
            <para>
              The distance between the two columns, the width of a rule between the columns, and the width of the columns, when the document class option
              <code>
                twocolumn
              </code>
               is in effect (
              <pxref label="Document-class-options">
                <xrefnodename>
                  Document class options
                </xrefnodename>
              </pxref>
              ).
              <xref label="_005ctwocolumn">
                <xrefnodename>
                  \twocolumn
                </xrefnodename>
              </xref>
              .
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                <indexterm index="fn" number="181" mergedindex="cp">
                  \headheight
                </indexterm>
                \headheight
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <findex index="fn" spaces=" ">
              <indexterm index="fn" number="182" mergedindex="cp">
                \headheight
              </indexterm>
            </findex>
            <anchor name="page-layout-parameters-headheight">
              page layout parameters headheight
            </anchor>
            <para>
              Height of the box that contains the running head. The default in the
              <code>
                article
              </code>
              ,
              <code>
                report
              </code>
              , and
              <code>
                book
              </code>
               classes is
              <samp>
                12pt
              </samp>
              , at all type sizes.
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                <indexterm index="fn" number="183" mergedindex="cp">
                  \headsep
                </indexterm>
                \headsep
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <findex index="fn" spaces=" ">
              <indexterm index="fn" number="184" mergedindex="cp">
                \headsep
              </indexterm>
            </findex>
            <anchor name="page-layout-parameters-headsep">
              page layout parameters headsep
            </anchor>
            <para>
              Vertical distance between the bottom of the header line and the top of the main text. The default in the
              <code>
                article
              </code>
               and
              <code>
                report
              </code>
               classes is
              <samp>
                25pt
              </samp>
              . In the
              <code>
                book
              </code>
               class the default is: if the document is set at 10pt then it is
              <samp>
                0.25in
              </samp>
              , and at 11pt or 12pt it is
              <samp>
                0.275in
              </samp>
              .
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                <indexterm index="fn" number="185" mergedindex="cp">
                  \footskip
                </indexterm>
                \footskip
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <findex index="fn" spaces=" ">
              <indexterm index="fn" number="186" mergedindex="cp">
                \footskip
              </indexterm>
            </findex>
            <anchor name="page-layout-parameters-footskip">
              page layout parameters footskip
            </anchor>
            <para>
              Distance from the baseline of the last line of text to the baseline of the page footer. The default in the
              <code>
                article
              </code>
               and
              <code>
                report
              </code>
               classes is
              <samp>
                30pt
              </samp>
              . In the
              <code>
                book
              </code>
               class the default is: when the type size is 10pt the default is
              <samp>
                0.35in
              </samp>
              , while at 11pt it is
              <samp>
                0.38in
              </samp>
              , and at 12pt it is
              <samp>
                30pt
              </samp>
              .
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                <indexterm index="fn" number="187" mergedindex="cp">
                  \linewidth
                </indexterm>
                \linewidth
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <findex index="fn" spaces=" ">
              <indexterm index="fn" number="188" mergedindex="cp">
                \linewidth
              </indexterm>
            </findex>
            <anchor name="page-layout-parameters-linewidth">
              page layout parameters linewidth
            </anchor>
            <para>
              Width of the current line, decreased for each nested
              <code>
                list
              </code>
               (
              <pxref label="list">
                <xrefnodename>
                  list
                </xrefnodename>
              </pxref>
              ). That is, the nominal value for
              <code>
                \linewidth
              </code>
               is to equal
              <code>
                \textwidth
              </code>
               but for each nested list the
              <code>
                \linewidth
              </code>
               is decreased by the sum of that list
Default handler: &textrsquo;
              s
              <code>
                \leftmargin
              </code>
               and
              <code>
                \rightmargin
              </code>
               (
              <pxref label="itemize">
                <xrefnodename>
                  itemize
                </xrefnodename>
              </pxref>
              ).
Default handler: <!-- c The default varies with the font size, paper width, two-column mode, -->
Default handler: <!-- c etc. For an @code{article} document set in 10pt, the default is -->
Default handler: <!-- c @samp{345pt}, while in two-column mode that becomes @samp{229.5pt}. -->
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                <indexterm index="fn" number="189" mergedindex="cp">
                  \marginparpush
                </indexterm>
                \marginparpush
              </itemformat>
            </item>
            <itemx spaces=" ">
              <itemformat command="code">
                <indexterm index="fn" number="190" mergedindex="cp">
                  \marginsep
                </indexterm>
                \marginsep
              </itemformat>
            </itemx>
            <itemx spaces=" ">
              <itemformat command="code">
                <indexterm index="fn" number="191" mergedindex="cp">
                  \marginparwidth
                </indexterm>
                \marginparwidth
              </itemformat>
            </itemx>
          </tableterm>
          <tableitem>
            <findex index="fn" spaces=" ">
              <indexterm index="fn" number="192" mergedindex="cp">
                \marginparpush
              </indexterm>
            </findex>
            <findex index="fn" spaces=" ">
              <indexterm index="fn" number="193" mergedindex="cp">
                \marginsep
              </indexterm>
            </findex>
            <findex index="fn" spaces=" ">
              <indexterm index="fn" number="194" mergedindex="cp">
                \marginparwidth
              </indexterm>
            </findex>
            <anchor name="page-layout-parameters-marginparpush">
              page layout parameters marginparpush
            </anchor>
            <anchor name="page-layout-parameters-marginsep">
              page layout parameters marginsep
            </anchor>
            <anchor name="page-layout-parameters-marginparwidth">
              page layout parameters marginparwidth
            </anchor>
            <para>
              The minimum vertical space between two marginal notes, the horizontal space between the text body and the marginal notes, and the horizontal width of the notes.
            </para>
            <para>
              Normally marginal notes appear on the outside of the page, but the declaration
              <code>
                \reversemarginpar
              </code>
               changes that (and
              <code>
                \normalmarginpar
              </code>
               changes it back).
            </para>
            <para>
              The defaults for
              <code>
                \marginparpush
              </code>
               in both
              <code>
                book
              </code>
               and
              <code>
                article
              </code>
               classes are:
              <samp>
                7pt
              </samp>
               if the document is set at 12pt, and
              <samp>
                5pt
              </samp>
               if the document is set at 11pt or 10pt.
            </para>
            <para>
              For
              <code>
                \marginsep
              </code>
              , in
              <code>
                article
              </code>
               class the default is
              <samp>
                10pt
              </samp>
               except if the document is set at 10pt and in two-column mode where the default is
              <samp>
                11pt
              </samp>
              .
            </para>
            <para>
              For
              <code>
                \marginsep
              </code>
               in
              <code>
                book
              </code>
               class the default is
              <samp>
                10pt
              </samp>
               in two-column mode and
              <samp>
                7pt
              </samp>
               in one-column mode.
            </para>
            <para>
              For
              <code>
                \marginparwidth
              </code>
               in both
              <code>
                book
              </code>
               and
              <code>
                article
              </code>
               classes, in two-column mode the default is 60% of
              <code>
                \paperwidth
Default handler: &minus;
                 \textwidth
              </code>
              , while in one-column mode it is 50% of that distance.
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                <indexterm index="fn" number="195" mergedindex="cp">
                  \oddsidemargin
                </indexterm>
                \oddsidemargin
              </itemformat>
            </item>
            <itemx spaces=" ">
              <itemformat command="code">
                <indexterm index="fn" number="196" mergedindex="cp">
                  \evensidemargin
                </indexterm>
                \evensidemargin
              </itemformat>
            </itemx>
          </tableterm>
          <tableitem>
            <findex index="fn" spaces=" ">
              <indexterm index="fn" number="197" mergedindex="cp">
                \oddsidemargin
              </indexterm>
            </findex>
            <findex index="fn" spaces=" ">
              <indexterm index="fn" number="198" mergedindex="cp">
                \evensidemargin
              </indexterm>
            </findex>
            <anchor name="page-layout-parameters-oddsidemargin">
              page layout parameters oddsidemargin
            </anchor>
            <anchor name="page-layout-parameters-evensidemargin">
              page layout parameters evensidemargin
            </anchor>
Default handler: <!-- c xx TODO re-align on French version that is more complete/accurate. -->
            <para>
              The
              <code>
                \oddsidemargin
              </code>
               length is the extra distance between the left side of the page and the text
Default handler: &textrsquo;
              s left margin, on odd-numbered pages when the document class option
              <code>
                twoside
              </code>
               is chosen and on all pages when
              <code>
                oneside
              </code>
               is in effect. When
              <code>
                twoside
              </code>
               is in effect, on even-numbered pages the extra distance on the left is
              <code>
                \evensidemargin
              </code>
              .
            </para>
            <paraDefault handler: &latex;
Default handler: &textrsquo;
>
              s default is that
              <code>
                \oddsidemargin
              </code>
               is 40% of the difference between
              <code>
                \paperwidth
              </code>
               and
              <code>
                \textwidth
              </code>
              , and
              <code>
                \evensidemargin
              </code>
               is the remainder.
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                <indexterm index="fn" number="199" mergedindex="cp">
                  \paperheight
                </indexterm>
                \paperheight
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <findex index="fn" spaces=" ">
              <indexterm index="fn" number="200" mergedindex="cp">
                \paperheight
              </indexterm>
            </findex>
            <anchor name="page-layout-parameters-paperheight">
              page layout parameters paperheight
            </anchor>
            <para>
              The height of the paper, as distinct from the height of the print area. Normally set with a document class option, as in
              <code>
                \documentclass[a4paper]
Default handler: &lbrace;
                article
Default handler: &rbrace;
              </code>
               (
              <pxref label="Document-class-options">
                <xrefnodename>
                  Document class options
                </xrefnodename>
              </pxref>
              ).
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                <indexterm index="fn" number="201" mergedindex="cp">
                  \paperwidth
                </indexterm>
                \paperwidth
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <findex index="fn" spaces=" ">
              <indexterm index="fn" number="202" mergedindex="cp">
                \paperwidth
              </indexterm>
            </findex>
            <anchor name="page-layout-parameters-paperwidth">
              page layout parameters paperwidth
            </anchor>
            <para>
              The width of the paper, as distinct from the width of the print area. Normally set with a document class option, as in
              <code>
                \documentclass[a4paper]
Default handler: &lbrace;
                article
Default handler: &rbrace;
              </code>
               (
              <pxref label="Document-class-options">
                <xrefnodename>
                  Document class options
                </xrefnodename>
              </pxref>
              ).
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                <indexterm index="fn" number="203" mergedindex="cp">
                  \textheight
                </indexterm>
                \textheight
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <findex index="fn" spaces=" ">
              <indexterm index="fn" number="204" mergedindex="cp">
                \textheight
              </indexterm>
            </findex>
            <anchor name="page-layout-parameters-textheight">
              page layout parameters textheight
            </anchor>
            <para>
              The normal vertical height of the page body. If the document is set at a nominal type size of 10pt then for an
              <code>
                article
              </code>
               or
              <code>
                report
              </code>
               the default is
              <samp>
                43\baselineskip
              </samp>
              , while for a
              <code>
                book
              </code>
               it is
              <samp>
                41\baselineskip
              </samp>
              . At a type size of 11pt the default is
              <samp>
                38\baselineskip
              </samp>
               for all document classes. At 12pt it is
              <samp>
                36\baselineskip
              </samp>
               for all classes.
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                <indexterm index="fn" number="205" mergedindex="cp">
                  \textwidth
                </indexterm>
                \textwidth
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <findex index="fn" spaces=" ">
              <indexterm index="fn" number="206" mergedindex="cp">
                \textwidth
              </indexterm>
            </findex>
            <anchor name="page-layout-parameters-textwidth">
              page layout parameters textwidth
            </anchor>
            <para>
              The full horizontal width of the entire page body. For an
              <code>
                article
              </code>
               or
              <code>
                report
              </code>
               document, the default is
              <samp>
                345pt
              </samp>
               when the chosen type size is 10pt, the default is
              <samp>
                360pt
              </samp>
               at 11pt, and it is
              <samp>
                390pt
              </samp>
               at 12pt. For a
              <code>
                book
              </code>
               document, the default is
              <samp>
                4.5in
              </samp>
               at a type size of 10pt, and
              <samp>
                5in
              </samp>
               at 11pt or 12pt.
            </para>
            <para>
              In multi-column output,
              <code>
                \textwidth
              </code>
               remains the width of the entire page body, while
              <code>
                \columnwidth
              </code>
               is the width of one column (
              <pxref label="_005ctwocolumn">
                <xrefnodename>
                  \twocolumn
                </xrefnodename>
              </pxref>
              ).
            </para>
            <para>
              In lists (
              <pxref label="list">
                <xrefnodename>
                  list
                </xrefnodename>
              </pxref>
              ),
              <code>
                \textwidth
              </code>
               remains the width of the entire page body (and
              <code>
                \columnwidth
              </code>
               the width of the entire column), while
              <code>
                \linewidth
              </code>
               may decrease for nested lists.
            </para>
            <para>
              Inside a minipage (
              <pxref label="minipage">
                <xrefnodename>
                  minipage
                </xrefnodename>
              </pxref>
              ) or
              <code>
                \parbox
              </code>
               (
              <pxref label="_005cparbox">
                <xrefnodename>
                  \parbox
                </xrefnodename>
              </pxref>
              ), all the width-related parameters are set to the specified width, and revert to their normal values at the end of the
              <code>
                minipage
              </code>
               or
              <code>
                \parbox
              </code>
              .
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                <indexterm index="fn" number="207" mergedindex="cp">
                  \hsize
                </indexterm>
                \hsize
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <findex index="fn" spaces=" ">
              <indexterm index="fn" number="208" mergedindex="cp">
                \hsize
              </indexterm>
            </findex>
            <anchor name="page-layout-parameters-hsize">
              page layout parameters hsize
            </anchor>
            <para>
              This entry is included for completeness:
              <code>
                \hsize
              </code>
               is the
Default handler: &tex;
               primitive parameter used when text is broken into lines. It should not be used in normal
Default handler: &latex;
               documents.
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                <indexterm index="fn" number="209" mergedindex="cp">
                  \topmargin
                </indexterm>
                \topmargin
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <findex index="fn" spaces=" ">
              <indexterm index="fn" number="210" mergedindex="cp">
                topmargin
              </indexterm>
            </findex>
            <anchor name="page-layout-parameters-topmargin">
              page layout parameters topmargin
            </anchor>
Default handler: <!-- c xxx TODO re-align on French version that is more accurate. -->
            <para>
              Space between the top of the
Default handler: &tex;
               page (one inch from the top of the paper, by default) and the top of the header. The value is computed based on many other parameters:
              <code>
                \paperheight
Default handler: &minus;
                 2in
Default handler: &minus;
                 \headheight
Default handler: &minus;
                 \headsep
Default handler: &minus;
                 \textheight
Default handler: &minus;
                 \footskip
              </code>
              , and then divided by two.
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                <indexterm index="fn" number="211" mergedindex="cp">
                  \topskip
                </indexterm>
                \topskip
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <findex index="fn" spaces=" ">
              <indexterm index="fn" number="212" mergedindex="cp">
                \topskip
              </indexterm>
            </findex>
            <anchor name="page-layout-parameters-topskip">
              page layout parameters topskip
            </anchor>
            <para>
              Minimum distance between the top of the page body and the baseline of the first line of text. For the standard classes, the default is the same as the font size, e.g.,
              <samp>
                10pt
              </samp>
               at a type size of 10pt.
            </para>
          </tableitem>
        </tableentry>
      </ftable>
    </section>
    <node name="_005cbaselineskip-_0026-_005cbaselinestretch" spaces=" ">
      <nodename>
        \baselineskip
        &
         \baselinestretch
      </nodename>
      <nodenext automatic="on">
        Floats
      </nodenext>
      <nodeprev automatic="on">
        Page layout parameters
      </nodeprev>
      <nodeup automatic="on">
        Layout
      </nodeup>
    </node>
    <section spaces=" ">
      <sectiontitle>
        <code>
          \baselineskip
        </code>
        &
        <code>
          \baselinestretch
        </code>
      </sectiontitle>
      <anchor name="_005cbaselineskip">
        \baselineskip
      </anchor>
      <anchor name="_005cbaselinestretch">
        \baselinestretch
      </anchor>
      <findex index="fn" spaces=" ">
        <indexterm index="fn" number="213" mergedindex="cp">
          \baselineskip
        </indexterm>
      </findex>
      <findex index="fn" spaces=" ">
        <indexterm index="fn" number="214" mergedindex="cp">
          \baselinestretch
        </indexterm>
      </findex>
      <findex index="fn" spaces=" ">
        <indexterm index="fn" number="215" mergedindex="cp">
          \linespread
        </indexterm>
      </findex>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="211">
          space between lines
        </indexterm>
      </cindex>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="212">
          interline space
        </indexterm>
      </cindex>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="213">
          leading
        </indexterm>
      </cindex>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="214">
          double spacing
        </indexterm>
      </cindex>
      <para>
        The
        <code>
          \baselineskip
        </code>
         is a rubber length (
        <pxref label="Lengths">
          <xrefnodename>
            Lengths
          </xrefnodename>
        </pxref>
        ). It gives the
        <dfn>
          leading
        </dfn>
        , the normal distance between lines in a paragraph, from baseline to baseline.
      </para>
      <para>
        Ordinarily document authors do not directly change
        <code>
          \baselineskip
        </code>
         while writing. Instead, it is set by the low level font selection command
        <code>
          \fontsize
        </code>
         (
        <pxref label="low-level-font-commands-fontsize">
          <xrefnodename>
            low level font commands fontsize
          </xrefnodename>
        </pxref>
        ). The
        <code>
          \baselineskip
        </code>
Default handler: &textrsquo;
        s value is reset every time a font change happens and so any direct change to
        <code>
          \baselineskip
        </code>
         would vanish the next time there was a font switch. For how to influence line spacing, see the discussion of
        <code>
          \baselinestretch
        </code>
         below.
      </para>
      <para>
        Usually, a font
Default handler: &textrsquo;
        s size and baseline skip is assigned by the font designer. These numbers are nominal in the sense that if, for instance, a font
Default handler: &textrsquo;
        s style file has the command
        <code>
          \fontsize
Default handler: &lbrace;
          10pt
Default handler: &rbrace;
Default handler: &lbrace;
          12pt
Default handler: &rbrace;
        </code>
         then that does not mean that the characters in the font are 10
        <dmn>
          pt
        </dmn>
         tall; for instance, parentheses and accented capitals may be taller. Nor does it mean that if the lines are spaced less than 12
        <dmn>
          pt
        </dmn>
         apart then they risk touching. Rather these numbers are typographic judgements. (Often, the
        <code>
          \baselineskip
        </code>
         is about twenty percent larger than the font size.)
      </para>
Default handler: <!-- c adapted from FAQ -->
      <para>
        The
        <code>
          \baselineskip
        </code>
         is not a property of each line but of the entire paragraph. As a result, large text in the middle of a paragraph, such as a single
        <codeDefault handler: &lbrace;
>
          \Huge Q
Default handler: &rbrace;
        </code>
        , will be squashed into its line.
Default handler: &tex;
         will make sure it doesn
Default handler: &textrsquo;
        t scrape up against the line above but won
Default handler: &textrsquo;
        t change the
        <code>
          \baselineskip
        </code>
         for that one line to make extra room above. For the fix, use a
        <code>
          \strut
        </code>
         (
        <pxref label="_005cstrut">
          <xrefnodename>
            \strut
          </xrefnodename>
        </pxref>
        ).
      </para>
      <para>
        The value of
        <code>
          \baselineskip
        </code>
         that
Default handler: &tex;
         uses for the paragraph is the value in effect at the blank line or command that ends the paragraph unit. So if a document contains this paragraph then its lines will be scrunched together, compared to lines in surrounding paragraphs.
      </para>
Default handler: <!-- c Adapted from B Beeton's "Lapses in TeX" TB 42:1 p 13. -->
      <example endspaces=" ">
        <pre xml:space="preserve">
          Many people see a page break between text and a displayed equation as bad style, so in effect the display is part of the paragraph. Because this display is in footnotesize, the entire paragraph has the baseline spacing matching that size.
Default handler: &lbrace;
          \footnotesize $$a+b = c$$
Default handler: &rbrace;
        </pre>
      </example>
      <findex index="fn" spaces=" ">
        <indexterm index="fn" number="216" mergedindex="cp">
          \lineskip
        </indexterm>
      </findex>
      <findex index="fn" spaces=" ">
        <indexterm index="fn" number="217" mergedindex="cp">
          \lineskiplimit
        </indexterm>
      </findex>
      <findex index="fn" spaces=" ">
        <indexterm index="fn" number="218" mergedindex="cp">
          \prevdepth
        </indexterm>
      </findex>
      <para>
        The process for making paragraphs is that when a new line is added, if the depth of the previous line plus the height of the new line is less than
        <code>
          \baselineskip
        </code>
         then
Default handler: &tex;
         inserts vertical glue to make up the difference. There are two fine points. The first is that if the lines would be too close together, closer than
        <code>
          \lineskiplimit
        </code>
        , then
Default handler: &tex;
         instead uses
        <code>
          \lineskip
        </code>
         as the interline glue. The second is that
Default handler: &tex;
         doesn
Default handler: &textrsquo;
        t actually use the depth of the previous line. Instead it uses
        <code>
          \prevdepth
        </code>
        , which usually contains that depth. But at the beginning of the paragraph (or any vertical list) or just after a rule,
        <code>
          \prevdepth
        </code>
         has the value -1000
        <dmn>
          pt
        </dmn>
         and this special value tells
Default handler: &tex;
         not to insert any interline glue at the paragraph start.
      </para>
      <para>
        In the standard classes
        <code>
          \lineskiplimit
        </code>
         is 0
        <dmn>
          pt
        </dmn>
         and
        <code>
          \lineskip
        </code>
         is 1
        <dmn>
          pt
        </dmn>
        . By the prior paragraph then, the distance between lines can approach zero but if it becomes zero (or less than zero) then the lines jump to 1
        <dmn>
          pt
        </dmn>
         apart.
      </para>
      <para>
        Sometimes authors must, for editing purposes, put the document in double space or one-and-a-half space. The right way to influence the interline distance is via
        <code>
          \baselinestretch
        </code>
        . It scales
        <code>
          \baselineskip
        </code>
        , and has a default value of 1.0. It is a command, not a length, and does not take effect until a font change happens, so set the scale factor like this:
        <code>
          \renewcommand
Default handler: &lbrace;
          \baselinestretch
Default handler: &rbrace;
Default handler: &lbrace;
          1.5
Default handler: &rbrace;
          \selectfont
        </code>
        .
      </para>
      <para>
        The most straightforward way to change the line spacing for an entire document is to put
        <code>
          \linespread
Default handler: &lbrace;
          <var>
            factor
          </var>
Default handler: &rbrace;
        </code>
         in the preamble. For double spacing, take
        <var>
          factor
        </var>
         to be 1.6 and for one-and-a-half spacing use 1.3. These numbers are rough: for instance, since the
        <code>
          \baselineskip
        </code>
         is about 1.2 times the font size, multiplying by 1.6 gives a baseline skip to font size ratio of about 2. (The
        <code>
          \linespread
        </code>
         command is defined as
        <code>
          \renewcommand
Default handler: &lbrace;
          \baselinestretch
Default handler: &rbrace;
Default handler: &lbrace;
          <var>
            factor
          </var>
Default handler: &rbrace;
        </code>
         so it also won
Default handler: &textrsquo;
        t take effect until a font setting happens. But that always takes place at the start of a document, so there you don
Default handler: &textrsquo;
        t need to follow it with
        <code>
          \selectfont
        </code>
        .)
      </para>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="215">
          <r>
            package
          </r>
          ,
          <code>
            setspace
          </code>
        </indexterm>
      </cindex>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="216">
          <code>
            setspace
          </code>
          <r>
            package
          </r>
        </indexterm>
      </cindex>
      <para>
        A simpler approach is the
        <code>
          setspace
        </code>
         package. The basic example:
      </para>
      <example endspaces=" ">
        <pre xml:space="preserve">
          \usepackage
Default handler: &lbrace;
          setspace
Default handler: &rbrace;
           \doublespacing % or \onehalfspacing for 1.5
        </pre>
      </example>
      <noindent/>
      <para>
        In the preamble these will start the document off with that sizing. But you can also use these declarations in the document body to change the spacing from that point forward, and consequently there is
        <code>
          \singlespacing
        </code>
         to return the spacing to normal. In the document body, a better practice than using the declarations is to use environments, such as
        <code>
          \begin
Default handler: &lbrace;
          doublespace
Default handler: &rbrace;
           ... \end
Default handler: &lbrace;
          doublespace
Default handler: &rbrace;
        </code>
        . The package also has commands to do arbitrary spacing:
        <code>
          \setstretch
Default handler: &lbrace;
          <var>
            factor
          </var>
Default handler: &rbrace;
        </code>
         and
        <code>
          \begin
Default handler: &lbrace;
          spacing
Default handler: &rbrace;
Default handler: &lbrace;
          <var>
            factor
          </var>
Default handler: &rbrace;
           ... \end
Default handler: &lbrace;
          spacing
Default handler: &rbrace;
        </code>
        . This package also keeps the line spacing single-spaced in places where that is typically desirable, such as footnotes and figure captions. See the package documentation.
      </para>
    </section>
    <node name="Floats" spaces=" ">
      <nodename>
        Floats
      </nodename>
      <nodeprev automatic="on">
        \baselineskip
        &
         \baselinestretch
      </nodeprev>
      <nodeup automatic="on">
        Layout
      </nodeup>
    </node>
    <section spaces=" ">
      <sectiontitle>
        Floats
      </sectiontitle>
      <para>
        Some typographic elements, such as figures and tables, cannot be broken across pages. They must be typeset outside of the normal flow of text, for instance floating to the top of a later page.
      </para>
      <paraDefault handler: &latex;
>
         can have a number of different classes of floating material. The default is the two classes,
        <code>
          figure
        </code>
         (
        <pxref label="figure">
          <xrefnodename>
            figure
          </xrefnodename>
        </pxref>
        ) and
        <code>
          table
        </code>
         (
        <pxref label="table">
          <xrefnodename>
            table
          </xrefnodename>
        </pxref>
        ), but you can create a new class with the package
        <code>
          float
        </code>
        .
      </para>
      <para>
        Within any one float class
Default handler: &latex;
         always respects the order, so that the first figure in a document source must be typeset before the second figure. However,
Default handler: &latex;
         may mix the classes, so it can happen that while the first table appears in the source before the first figure, it appears in the output after it.
      </para>
      <para>
        The placement of floats is subject to parameters, given below, that limit the number of floats that can appear at the top of a page, and the bottom, etc. If so many floats are queued that the limits prevent them all from fitting on a page then
Default handler: &latex;
         places what it can and defers the rest to the next page. In this way, floats may end up being typeset far from their place in the source. In particular, a float that is big may migrate to the end of the document. In which event, because all floats in a class must appear in sequential order, every following float in that class also appears at the end.
      </para>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="217">
          placement of floats
        </indexterm>
      </cindex>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="218">
          specifier, float placement
        </indexterm>
      </cindex>
      <para>
        In addition to changing the parameters, for each float you can tweak where the float placement algorithm tries to place it by using its
        <var>
          placement
        </var>
         argument. The possible values are a sequence of the letters below. The default for both
        <code>
          figure
        </code>
         and
        <code>
          table
        </code>
        , in both
        <code>
          article
        </code>
         and
        <code>
          book
        </code>
         classes, is
        <code>
          tbp
        </code>
        .
      </para>
      <table commandarg="code" spaces=" " endspaces=" ">
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                t
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <para>
              (Top)
Default handler: &textmdash;
              at the top of a text page.
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                b
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <para>
              (Bottom)
Default handler: &textmdash;
              at the bottom of a text page. (However,
              <code>
                b
              </code>
               is not allowed for full-width floats (
              <code>
                figure*
              </code>
              ) with double-column output. To ameliorate this, use the
              <file>
                stfloats
              </file>
               or
              <file>
                dblfloatfix
              </file>
               package, but see the discussion at caveats in the FAQ:
              <url>
                <urefurl>
                  https://www.texfaq.org/FAQ-2colfloat
                </urefurl>
              </url>
              .
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                h
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <para>
              (Here)
Default handler: &textmdash;
              at the position in the text where the
              <code>
                figure
              </code>
               environment appears. However,
              <code>
                h
              </code>
               is not allowed by itself;
              <code>
                t
              </code>
               is automatically added.
            </para>
            <cindex index="cp" spaces=" ">
              <indexterm index="cp" number="219">
                here, putting floats
              </indexterm>
            </cindex>
            <cindex index="cp" spaces=" ">
              <indexterm index="cp" number="220">
                <r>
                  package
                </r>
                ,
                <code>
                  float
                </code>
              </indexterm>
            </cindex>
            <cindex index="cp" spaces=" ">
              <indexterm index="cp" number="221">
                <code>
                  float
                </code>
                <r>
                  package
                </r>
              </indexterm>
            </cindex>
            <para>
              To absolutely force a float to appear
Default handler: &textldquo;
              here
Default handler: &textrdquo;
              , you can
              <code>
                \usepackage
Default handler: &lbrace;
                float
Default handler: &rbrace;
              </code>
               and use the
              <code>
                H
              </code>
               specifier which it defines. For further discussion, see the FAQ entry at
              <url>
                <urefurl>
                  https://www.texfaq.org/FAQ-figurehere
                </urefurl>
              </url>
              .
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                p
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <cindex index="cp" spaces=" ">
              <indexterm index="cp" number="222">
                float page
              </indexterm>
            </cindex>
            <para>
              (Page of floats)
Default handler: &textmdash;
              on a separate
              <dfn>
                float page
              </dfn>
              , which is a page containing no text, only floats.
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                !
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <para>
              Used in addition to one of the above; for this float only,
Default handler: &latex;
               ignores the restrictions on both the number of floats that can appear and the relative amounts of float and non-float text on the page. The
              <code>
                !
              </code>
               specifier does
              <emph>
                not
              </emph>
               mean
Default handler: &textldquo;
              put the float here
Default handler: &textrdquo;
              ; see above.
            </para>
          </tableitem>
        </tableentry>
      </table>
      <para>
        Note: the order in which letters appear in the
        <var>
          placement
        </var>
         argument does not change the order in which
Default handler: &latex;
         tries to place the float; for instance,
        <code>
          btp
        </code>
         has the same effect as
        <code>
          tbp
        </code>
        . All that
        <var>
          placement
        </var>
         does is that if a letter is not present then the algorithm does not try that location. Thus,
Default handler: &latex;
Default handler: &textrsquo;
        s default of
        <code>
          tbp
        </code>
         is to try every location except placing the float where it occurs in the source.
      </para>
      <para>
        To prevent
Default handler: &latex;
         from moving floats to the end of the document or a chapter you can use a
        <code>
          \clearpage
        </code>
         command to start a new page and insert all pending floats. If a pagebreak is undesirable then you can use the
        <file>
          afterpage
        </file>
         package and issue
        <code>
          \afterpage
Default handler: &lbrace;
          \clearpage
Default handler: &rbrace;
        </code>
        . This will wait until the current page is finished and then flush all outstanding floats.
      </para>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="223">
          <r>
            package
          </r>
          ,
          <code>
            flafter
          </code>
        </indexterm>
      </cindex>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="224">
          <code>
            flafter
          </code>
          <r>
            package
          </r>
        </indexterm>
      </cindex>
      <paraDefault handler: &latex;
>
         can typeset a float before where it appears in the source (although on the same output page) if there is a
        <code>
          t
        </code>
         specifier in the
        <var>
          placement
        </var>
         parameter. If this is not desired, and deleting the
        <code>
          t
        </code>
         is not acceptable as it keeps the float from being placed at the top of the next page, then you can prevent it by either using the
        <code>
          flafter
        </code>
         package or using the command
        <findex index="fn" spaces=" ">
          <indexterm index="fn" number="219" mergedindex="cp">
            \suppressfloats
          </indexterm>
        </findex>
        <code>
          \suppressfloats[t]
        </code>
        , which causes floats for the top position on this page to moved to the next page.
      </para>
      <para>
        Parameters relating to fractions of pages occupied by float and non-float text (change them with
        <code>
          \renewcommand
Default handler: &lbrace;
          <var>
            parameter
          </var>
Default handler: &rbrace;
Default handler: &lbrace;
          <var>
            decimal between 0 and 1
          </var>
Default handler: &rbrace;
        </code>
        ):
      </para>
      <ftable commandarg="code" spaces=" " endspaces=" ">
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                <indexterm index="fn" number="220" mergedindex="cp">
                  \bottomfraction
                </indexterm>
                \bottomfraction
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <findex index="fn" spaces=" ">
              <indexterm index="fn" number="221" mergedindex="cp">
                \bottomfraction
              </indexterm>
            </findex>
            <anchor name="floats-bottomfraction">
              floats bottomfraction
            </anchor>
            <para>
              The maximum fraction of the page allowed to be occupied by floats at the bottom; default
              <samp>
                .3
              </samp>
              .
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                <indexterm index="fn" number="222" mergedindex="cp">
                  \floatpagefraction
                </indexterm>
                \floatpagefraction
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <findex index="fn" spaces=" ">
              <indexterm index="fn" number="223" mergedindex="cp">
                \floatpagefraction
              </indexterm>
            </findex>
            <anchor name="floats-floatpagefraction">
              floats floatpagefraction
            </anchor>
            <para>
              The minimum fraction of a float page that must be occupied by floats; default
              <samp>
                .5
              </samp>
              .
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                <indexterm index="fn" number="224" mergedindex="cp">
                  \textfraction
                </indexterm>
                \textfraction
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <findex index="fn" spaces=" ">
              <indexterm index="fn" number="225" mergedindex="cp">
                \textfraction
              </indexterm>
            </findex>
            <anchor name="floats-textfraction">
              floats textfraction
            </anchor>
            <para>
              Minimum fraction of a page that must be text; if floats take up too much space to preserve this much text, floats will be moved to a different page. The default is
              <samp>
                .2
              </samp>
              .
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                <indexterm index="fn" number="226" mergedindex="cp">
                  \topfraction
                </indexterm>
                \topfraction
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <findex index="fn" spaces=" ">
              <indexterm index="fn" number="227" mergedindex="cp">
                \topfraction
              </indexterm>
            </findex>
            <anchor name="floats-topfraction">
              floats topfraction
            </anchor>
            <para>
              Maximum fraction at the top of a page that may be occupied before floats; default
              <samp>
                .7
              </samp>
              .
            </para>
          </tableitem>
        </tableentry>
      </ftable>
      <para>
        Parameters relating to vertical space around floats (change them with a command of the form
        <code>
          \setlength
Default handler: &lbrace;
          <var>
            parameter
          </var>
Default handler: &rbrace;
Default handler: &lbrace;
          <var>
            length expression
          </var>
Default handler: &rbrace;
        </code>
        ):
      </para>
      <ftable commandarg="code" spaces=" " endspaces=" ">
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                <indexterm index="fn" number="228" mergedindex="cp">
                  \floatsep
                </indexterm>
                \floatsep
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <findex index="fn" spaces=" ">
              <indexterm index="fn" number="229" mergedindex="cp">
                \floatsep
              </indexterm>
            </findex>
            <anchor name="floats-floatsep">
              floats floatsep
            </anchor>
            <para>
              Space between floats at the top or bottom of a page; default
              <samp>
                12pt plus2pt minus2pt
              </samp>
              .
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                <indexterm index="fn" number="230" mergedindex="cp">
                  \intextsep
                </indexterm>
                \intextsep
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <findex index="fn" spaces=" ">
              <indexterm index="fn" number="231" mergedindex="cp">
                \intextsep
              </indexterm>
            </findex>
            <anchor name="floats-intextsep">
              floats intextsep
            </anchor>
            <para>
              Space above and below a float in the middle of the main text; default
              <samp>
                12pt plus2pt minus2pt
              </samp>
               for 10 point and 11 point documents, and
              <samp>
                14pt plus4pt minus4pt
              </samp>
               for 12 point documents.
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                <indexterm index="fn" number="232" mergedindex="cp">
                  \textfloatsep
                </indexterm>
                \textfloatsep
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <findex index="fn" spaces=" ">
              <indexterm index="fn" number="233" mergedindex="cp">
                \textfloatsep
              </indexterm>
            </findex>
            <anchor name="floats-textfloatsep">
              floats textfloatsep
            </anchor>
            <para>
              Space between the last (first) float at the top (bottom) of a page; default
              <samp>
                20pt plus2pt minus4pt
              </samp>
              .
            </para>
          </tableitem>
        </tableentry>
      </ftable>
      <para>
        Counters relating to the number of floats on a page (change them with a command of the form
        <code>
          \setcounter
Default handler: &lbrace;
          <var>
            ctrname
          </var>
Default handler: &rbrace;
Default handler: &lbrace;
          <var>
            natural number
          </var>
Default handler: &rbrace;
        </code>
        ):
      </para>
      <ftable commandarg="code" spaces=" " endspaces=" ">
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                <indexterm index="fn" number="234" mergedindex="cp">
                  bottomnumber
                </indexterm>
                bottomnumber
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <findex index="fn" spaces=" ">
              <indexterm index="fn" number="235" mergedindex="cp">
                bottomnumber
              </indexterm>
            </findex>
            <anchor name="floats-bottomnumber">
              floats bottomnumber
            </anchor>
            <para>
              Maximum number of floats that can appear at the bottom of a text page; default 1.
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                <indexterm index="fn" number="236" mergedindex="cp">
                  dbltopnumber
                </indexterm>
                dbltopnumber
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <findex index="fn" spaces=" ">
              <indexterm index="fn" number="237" mergedindex="cp">
                dbltopnumber
              </indexterm>
            </findex>
            <anchor name="floats-dbltopnumber">
              floats dbltopnumber
            </anchor>
            <para>
              Maximum number of full-sized floats that can appear at the top of a two-column page; default 2.
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                <indexterm index="fn" number="238" mergedindex="cp">
                  topnumber
                </indexterm>
                topnumber
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <findex index="fn" spaces=" ">
              <indexterm index="fn" number="239" mergedindex="cp">
                topnumber
              </indexterm>
            </findex>
            <anchor name="floats-topnumber">
              floats topnumber
            </anchor>
            <para>
              Maximum number of floats that can appear at the top of a text page; default 2.
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                <indexterm index="fn" number="240" mergedindex="cp">
                  totalnumber
                </indexterm>
                totalnumber
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <findex index="fn" spaces=" ">
              <indexterm index="fn" number="241" mergedindex="cp">
                totalnumber
              </indexterm>
            </findex>
            <anchor name="floats-totalnumber">
              floats totalnumber
            </anchor>
            <para>
              Maximum number of floats that can appear on a text page; default 3.
            </para>
          </tableitem>
        </tableentry>
      </ftable>
      <para>
        The principal
Default handler: &tex;
Default handler: &nbsp;
        FAQ entry relating to floats
        <url>
          <urefurl>
            https://www.texfaq.org/FAQ-floats
          </urefurl>
        </url>
         contains suggestions for relaxing
Default handler: &latex;
Default handler: &textrsquo;
        s default parameters to reduce the problem of floats being pushed to the end. A full explanation of the float placement algorithm is in Frank Mittelbach
Default handler: &textrsquo;
        s article
Default handler: &textldquo;
        How to influence the position of float environments like figure and table in
Default handler: &latex;
        ?
Default handler: &textrdquo;
         (
        <url>
          <urefurl>
            https://www.latex-project.org/publications/2014-FMi-TUB-tb111mitt-float-placement.pdf
          </urefurl>
        </url>
        ).
      </para>
      <menu endspaces=" ">
        <menuentry>
          <menuleadingtext>
            *
          </menuleadingtext>
          <menunode>
            \caption
          </menunode>
          <menuseparator>
            ::
          </menuseparator>
          <menudescription>
            <pre xml:space="preserve">
              Make a caption for a floating environment.
            </pre>
          </menudescription>
        </menuentry>
      </menu>
      <node name="_005ccaption" spaces=" ">
        <nodename>
          \caption
        </nodename>
        <nodeup automatic="on">
          Floats
        </nodeup>
      </node>
      <subsection spaces=" ">
        <sectiontitle>
          <code>
            \caption
          </code>
        </sectiontitle>
        <findex index="fn" spaces=" ">
          <indexterm index="fn" number="242" mergedindex="cp">
            \caption
          </indexterm>
        </findex>
        <cindex index="cp" spaces=" ">
          <indexterm index="cp" number="225">
            captions
          </indexterm>
        </cindex>
        <para>
          Synopsis:
        </para>
        <example endspaces=" ">
          <pre xml:space="preserve">
            \caption
Default handler: &lbrace;
            <var>
              caption-text
            </var>
Default handler: &rbrace;
          </pre>
        </example>
        <noindent/>
        <para>
          or
        </para>
        <example endspaces=" ">
          <pre xml:space="preserve">
            \caption[
            <var>
              short-caption-text
            </var>
            ]
Default handler: &lbrace;
            <var>
              caption-text
            </var>
Default handler: &rbrace;
          </pre>
        </example>
        <para>
          Make a caption for a floating environment, such as a
          <code>
            figure
          </code>
           or
          <code>
            table
          </code>
           environment (
          <pxref label="figure">
            <xrefnodename>
              figure
            </xrefnodename>
          </pxref>
           or
          <ref label="table">
            <xrefnodename>
              table
            </xrefnodename>
          </ref>
          ).
        </para>
        <para>
          In this example,
Default handler: &latex;
           places a caption below the vertical blank space that is left by the author for the later inclusion of a picture.
        </para>
        <example endspaces=" ">
          <pre xml:space="preserve">
            \begin
Default handler: &lbrace;
            figure
Default handler: &rbrace;
             \vspace*
Default handler: &lbrace;
            1cm
Default handler: &rbrace;
             \caption
Default handler: &lbrace;
            Alonzo Cushing, Battery A, 4th US Artillery.
Default handler: &rbrace;
             \label
Default handler: &lbrace;
            fig:CushingPic
Default handler: &rbrace;
             \end
Default handler: &lbrace;
            figure
Default handler: &rbrace;
          </pre>
        </example>
        <noindent/>
        <para>
          The
          <code>
            \caption
          </code>
           command will label the
          <var>
            caption-text
          </var>
           with something like
          <samp>
            Figure
Default handler: &nbsp;
            1:
          </samp>
           for an article or
          <samp>
            Figure
Default handler: &nbsp;
            1.1:
          </samp>
           for a book. The text is centered if it is shorter than the text width, or set as an unindented paragraph if it takes more than one line.
        </para>
        <para>
          In addition to placing the
          <var>
            caption-text
          </var>
           in the output, the
          <code>
            \caption
          </code>
           command also saves that information for use in a list of figures or list of tables (
          <pxref label="Table-of-contents-etc_002e">
            <xrefnodename>
              Table of contents etc.
            </xrefnodename>
          </pxref>
          ).
        </para>
        <para>
          Here the
          <code>
            \caption
          </code>
           command uses the optional
          <var>
            short-caption-text
          </var>
          , so that the shorter text appears in the list of tables, rather than the longer
          <var>
            caption-text
          </var>
          .
        </para>
        <example endspaces=" ">
          <pre xml:space="preserve">
            \begin
Default handler: &lbrace;
            table
Default handler: &rbrace;
             \centering \begin
Default handler: &lbrace;
            tabular
Default handler: &rbrace;
Default handler: &lbrace;
            |*
Default handler: &lbrace;
            3
Default handler: &rbrace;
Default handler: &lbrace;
            c
Default handler: &rbrace;
            |
Default handler: &rbrace;
             \hline 4
            &
            9
            &
            2 \\ 3
            &
            5
            &
            7 \\ 8
            &
            1
            &
            6 \\ \hline \end
Default handler: &lbrace;
            tabular
Default handler: &rbrace;
             \caption[\textit
Default handler: &lbrace;
            Lo Shu
Default handler: &rbrace;
             magic square]
Default handler: &lbrace;
            % The \textit
Default handler: &lbrace;
            Lo Shu
Default handler: &rbrace;
             magic square, which is unique among squares of order three up to rotation and reflection.
Default handler: &rbrace;
             \label
Default handler: &lbrace;
            tab:LoShu
Default handler: &rbrace;
             \end
Default handler: &lbrace;
            table
Default handler: &rbrace;
          </pre>
        </example>
        <noindent/>
        <paraDefault handler: &latex;
>
           will label the
          <var>
            caption-text
          </var>
           with something like
          <samp>
            Table
Default handler: &nbsp;
            1:
          </samp>
           for an article or
          <samp>
            Table
Default handler: &nbsp;
            1.1:
          </samp>
           for a book.
        </para>
        <para>
          The caption can appear at the top of the
          <code>
            figure
          </code>
           or
          <code>
            table
          </code>
          . For instance, that would happen in the prior example by putting the
          <code>
            \caption
          </code>
           between the
          <code>
            \centering
          </code>
           and the
          <code>
            \begin
Default handler: &lbrace;
            tabular
Default handler: &rbrace;
          </code>
          .
        </para>
        <para>
          Different floating environments are numbered separately, by default. It is
          <code>
            \caption
          </code>
           that updates the counter, and so any
          <code>
            \label
          </code>
           must come after the
          <code>
            \caption
          </code>
          . The counter for the
          <code>
            figure
          </code>
           environment is named
          <code>
            figure
          </code>
          , and similarly the counter for the
          <code>
            table
          </code>
           environment is
          <code>
            table
          </code>
          .
        </para>
        <para>
          The text that will be put in the list of figures or list of tables is moving argument. If you get the
Default handler: &latex;
           error
          <samp>
            ! Argument of \
Default handler: &arobase;
            caption has an extra
Default handler: &rbrace;
          </samp>
           then you must put
          <code>
            \protect
          </code>
           in front of any fragile commands.
          <xref label="_005cprotect">
            <xrefnodename>
              \protect
            </xrefnodename>
          </xref>
          .
        </para>
        <cindex index="cp" spaces=" ">
          <indexterm index="cp" number="226">
            <r>
              package
            </r>
            ,
            <code>
              caption
            </code>
          </indexterm>
        </cindex>
        <cindex index="cp" spaces=" ">
          <indexterm index="cp" number="227">
            <code>
              caption
            </code>
            <r>
              package
            </r>
          </indexterm>
        </cindex>
        <para>
          The
          <code>
            caption
          </code>
           package has many options to adjust how the caption appears, for example changing the font size, making the caption be hanging text rather than set as a paragraph, or making the caption always set as a paragraph rather than centered when it is short.
        </para>
      </subsection>
    </section>
  </chapter>
  <node name="Sectioning" spaces=" ">
    <nodename>
      Sectioning
    </nodename>
    <nodenext automatic="on">
      Cross references
    </nodenext>
    <nodeprev automatic="on">
      Layout
    </nodeprev>
    <nodeup automatic="on">
      Top
    </nodeup>
  </node>
  <chapter spaces=" ">
    <sectiontitle>
      Sectioning
    </sectiontitle>
    <cindex index="cp" spaces=" ">
      <indexterm index="cp" number="228">
        sectioning commands
      </indexterm>
    </cindex>
    <cindex index="cp" spaces=" ">
      <indexterm index="cp" number="229">
        part
      </indexterm>
    </cindex>
    <cindex index="cp" spaces=" ">
      <indexterm index="cp" number="230">
        chapter
      </indexterm>
    </cindex>
    <cindex index="cp" spaces=" ">
      <indexterm index="cp" number="231">
        section
      </indexterm>
    </cindex>
    <cindex index="cp" spaces=" ">
      <indexterm index="cp" number="232">
        subsection
      </indexterm>
    </cindex>
    <cindex index="cp" spaces=" ">
      <indexterm index="cp" number="233">
        subsubsection
      </indexterm>
    </cindex>
    <cindex index="cp" spaces=" ">
      <indexterm index="cp" number="234">
        paragraph
      </indexterm>
    </cindex>
    <cindex index="cp" spaces=" ">
      <indexterm index="cp" number="235">
        subparagraph
      </indexterm>
    </cindex>
    <findex index="fn" spaces=" ">
      <indexterm index="fn" number="243" mergedindex="cp">
        \part
      </indexterm>
    </findex>
    <findex index="fn" spaces=" ">
      <indexterm index="fn" number="244" mergedindex="cp">
        \chapter
      </indexterm>
    </findex>
    <findex index="fn" spaces=" ">
      <indexterm index="fn" number="245" mergedindex="cp">
        \section
      </indexterm>
    </findex>
    <findex index="fn" spaces=" ">
      <indexterm index="fn" number="246" mergedindex="cp">
        \subsection
      </indexterm>
    </findex>
    <findex index="fn" spaces=" ">
      <indexterm index="fn" number="247" mergedindex="cp">
        \subsubsection
      </indexterm>
    </findex>
    <findex index="fn" spaces=" ">
      <indexterm index="fn" number="248" mergedindex="cp">
        \paragraph
      </indexterm>
    </findex>
    <findex index="fn" spaces=" ">
      <indexterm index="fn" number="249" mergedindex="cp">
        \subparagraph
      </indexterm>
    </findex>
    <para>
      Structure your text into divisions: parts, chapters, sections, etc. All sectioning commands have the same form, one of:
    </para>
    <example endspaces=" ">
      <pre xml:space="preserve">
        <var>
          sectioning-command
        </var>
Default handler: &lbrace;
        <var>
          title
        </var>
Default handler: &rbrace;
        <var>
          sectioning-command
        </var>
        *
Default handler: &lbrace;
        <var>
          title
        </var>
Default handler: &rbrace;
        <var>
          sectioning-command
        </var>
        [
        <var>
          toc-title
        </var>
        ]
Default handler: &lbrace;
        <var>
          title
        </var>
Default handler: &rbrace;
      </pre>
    </example>
    <noindent/>
    <para>
      For instance, declare the start of a subsection as with
      <code>
        \subsection
Default handler: &lbrace;
        Motivation
Default handler: &rbrace;
      </code>
      .
    </para>
    <para>
      The table has each
      <var>
        sectioning-command
      </var>
       in
Default handler: &latex;
      . All are available in all of
Default handler: &latex;
Default handler: &textrsquo;
      s standard document classes
      <code>
        book
      </code>
      ,
      <code>
        report
      </code>
      , and
Default handler: &nbsp;
      <code>
        article
      </code>
      , except that
      <code>
        \chapter
      </code>
       is not available in
      <code>
        article
      </code>
      .
    </para>
    <multitable spaces=" " endspaces=" ">
      <columnfractions spaces=" " line=".25 .25 .40 ">
        <columnfraction value=".25"/>
        <columnfraction value=".25"/>
        <columnfraction value=".40"/>
      </columnfractions>
      <thead>
        <row>
          <entry command="headitem">
            <para>
              Sectioning unit
            </para>
          </entry>
          <entry command="tab">
            <para>
              Command
            </para>
          </entry>
          <entry command="tab">
            <para>
              Level
            </para>
          </entry>
        </row>
      </thead>
      <tbody>
        <row>
          <entry command="item">
            <para>
              Part
            </para>
          </entry>
          <entry command="tab">
            <para>
              <code>
                \part
              </code>
            </para>
          </entry>
          <entry command="tab">
            <para>
              -1 (
              <code>
                book
              </code>
              ,
              <code>
                report
              </code>
              ), 0 (
              <code>
                article
              </code>
              )
            </para>
          </entry>
        </row>
        <row>
          <entry command="item">
            <para>
              Chapter
            </para>
          </entry>
          <entry command="tab">
            <para>
              <code>
                \chapter
              </code>
            </para>
          </entry>
          <entry command="tab">
            <para>
              0
            </para>
          </entry>
        </row>
        <row>
          <entry command="item">
            <para>
              Section
            </para>
          </entry>
          <entry command="tab">
            <para>
              <code>
                \section
              </code>
            </para>
          </entry>
          <entry command="tab">
            <para>
              1
            </para>
          </entry>
        </row>
        <row>
          <entry command="item">
            <para>
              Subsection
            </para>
          </entry>
          <entry command="tab">
            <para>
              <code>
                \subsection
              </code>
            </para>
          </entry>
          <entry command="tab">
            <para>
              2
            </para>
          </entry>
        </row>
        <row>
          <entry command="item">
            <para>
              Subsubsection
            </para>
          </entry>
          <entry command="tab">
            <para>
              <code>
                \subsubsection
              </code>
            </para>
          </entry>
          <entry command="tab">
            <para>
              3
            </para>
          </entry>
        </row>
        <row>
          <entry command="item">
            <para>
              Paragraph
            </para>
          </entry>
          <entry command="tab">
            <para>
              <code>
                \paragraph
              </code>
            </para>
          </entry>
          <entry command="tab">
            <para>
              4
            </para>
          </entry>
        </row>
        <row>
          <entry command="item">
            <para>
              Subparagraph
            </para>
          </entry>
          <entry command="tab">
            <para>
              <code>
                \subparagraph
              </code>
            </para>
          </entry>
          <entry command="tab">
            <para>
              5
            </para>
          </entry>
        </row>
      </tbody>
    </multitable>
    <cindex index="cp" spaces=" ">
      <indexterm index="cp" number="236">
        <code>
          *
        </code>
        -form of sectioning commands
      </indexterm>
    </cindex>
    <para>
      All these commands have a
      <code>
        *
      </code>
      -form that prints
      <var>
        title
      </var>
       as usual but does not number it and does not make an entry in the table of contents. An example of using this is for an appendix in an
      <code>
        article
      </code>
      . The input
      <code>
        \appendix\section
Default handler: &lbrace;
        Appendix
Default handler: &rbrace;
      </code>
       gives the output
      <samp>
        A Appendix
      </samp>
       (
      <pxref label="_005cappendix">
        <xrefnodename>
          \appendix
        </xrefnodename>
      </pxref>
      ). You can lose the numbering
Default handler: &nbsp;
      <samp>
        A
      </samp>
       by instead entering
      <code>
        \section*
Default handler: &lbrace;
        Appendix
Default handler: &rbrace;
      </code>
       (articles often omit a table of contents and have simple page headers so the other differences from the
      <code>
        \section
      </code>
       command may not matter).
    </para>
    <para>
      The section title
      <var>
        title
      </var>
       provides the heading in the main text, but it may also appear in the table of contents and in the running head or foot (
      <pxref label="Page-styles">
        <xrefnodename>
          Page styles
        </xrefnodename>
      </pxref>
      ). You may not want the same text in these places as in the main text. All of these commands have an optional argument
      <var>
        toc-title
      </var>
       for these other places.
    </para>
    <para>
      The level number in the table above determines which sectional units are numbered, and which appear in the table of contents. If the sectioning command
Default handler: &textrsquo;
      s
      <var>
        level
      </var>
       is less than or equal to the value of the counter
      <code>
        secnumdepth
      </code>
       then the titles for this sectioning command will be numbered (
      <pxref label="Sectioning_002fsecnumdepth">
        <xrefnodename>
          Sectioning/secnumdepth
        </xrefnodename>
      </pxref>
      ). And, if
      <var>
        level
      </var>
       is less than or equal to the value of the counter
      <code>
        tocdepth
      </code>
       then the table of contents will have an entry for this sectioning unit (
      <pxref label="Sectioning_002ftocdepth">
        <xrefnodename>
          Sectioning/tocdepth
        </xrefnodename>
      </pxref>
      ).
    </para>
    <paraDefault handler: &latex;
>
       expects that before you have a
      <code>
        \subsection
      </code>
       you will have a
      <code>
        \section
      </code>
       and, in a
      <code>
        book
      </code>
       class document, that before a
      <code>
        \section
      </code>
       you will have a
      <code>
        \chapter
      </code>
      . Otherwise you can get something like a subsection numbered
      <samp>
        3.0.1
      </samp>
      .
    </para>
    <cindex index="cp" spaces=" ">
      <indexterm index="cp" number="237">
        <r>
          package
        </r>
        ,
        <code>
          titlesec
        </code>
      </indexterm>
    </cindex>
    <cindex index="cp" spaces=" ">
      <indexterm index="cp" number="238">
        <code>
          titlesec
        </code>
        <r>
          package
        </r>
      </indexterm>
    </cindex>
    <paraDefault handler: &latex;
>
       lets you change the appearance of the sectional units. As a simple example, you can change the section numbering to uppercase letters with this (in the preamble):
Default handler: &linebreak;
      <code>
        \renewcommand\thesection
Default handler: &lbrace;
        \Alph
Default handler: &lbrace;
        section
Default handler: &rbrace;
Default handler: &rbrace;
      </code>
       . (
      <xref label="_005calph-_005cAlph-_005carabic-_005croman-_005cRoman-_005cfnsymbol">
        <xrefnodename>
          \alph \Alph \arabic \roman \Roman \fnsymbol
        </xrefnodename>
      </xref>
      .) CTAN has many packages that make this adjustment easier, notably
      <code>
        titlesec
      </code>
      .
    </para>
    <para>
      Two counters relate to the appearance of headings made by sectioning commands.
    </para>
    <ftable commandarg="code" spaces=" " endspaces=" ">
      <tableentry>
        <tableterm>
          <item spaces=" ">
            <itemformat command="code">
              <indexterm index="fn" number="250" mergedindex="cp">
                secnumdepth
              </indexterm>
              secnumdepth
            </itemformat>
          </item>
        </tableterm>
        <tableitem>
          <findex index="fn" spaces=" ">
            <indexterm index="fn" number="251" mergedindex="cp">
              secnumdepth
              <r>
                counter
              </r>
            </indexterm>
          </findex>
          <cindex index="cp" spaces=" ">
            <indexterm index="cp" number="239">
              section numbers, printing
            </indexterm>
          </cindex>
          <anchor name="sectioning-secnumdepth">
            sectioning secnumdepth
          </anchor>
          <anchor name="Sectioning_002fsecnumdepth">
            Sectioning/secnumdepth
          </anchor>
          <para>
            Controls which sectioning unit are numbered. Setting the counter with
            <code>
              \setcounter
Default handler: &lbrace;
              secnumdepth
Default handler: &rbrace;
Default handler: &lbrace;
              <var>
                level
              </var>
Default handler: &rbrace;
            </code>
             will suppress numbering of sectioning at any depth greater than
            <var>
              level
            </var>
             (
            <pxref label="_005csetcounter">
              <xrefnodename>
                \setcounter
              </xrefnodename>
            </pxref>
            ). See the above table for the level numbers. For instance, if the
            <code>
              secnumdepth
            </code>
             is 1 in an
            <code>
              article
            </code>
             then a
            <code>
              \section
Default handler: &lbrace;
              Introduction
Default handler: &rbrace;
            </code>
             command will produce output like
            <samp>
              1 Introduction
            </samp>
             while
            <code>
              \subsection
Default handler: &lbrace;
              Discussion
Default handler: &rbrace;
            </code>
             will produce output like
            <samp>
              Discussion
            </samp>
            , without the number.
Default handler: &latex;
Default handler: &textrsquo;
            s default
            <code>
              secnumdepth
            </code>
             is
Default handler: &nbsp;
            3 in
            <file>
              article
            </file>
             class and
Default handler: &nbsp;
            2 in the
            <file>
              book
            </file>
             and
            <file>
              report
            </file>
             classes.
          </para>
        </tableitem>
      </tableentry>
      <tableentry>
        <tableterm>
          <item spaces=" ">
            <itemformat command="code">
              <indexterm index="fn" number="252" mergedindex="cp">
                tocdepth
              </indexterm>
              tocdepth
            </itemformat>
          </item>
        </tableterm>
        <tableitem>
          <findex index="fn" spaces=" ">
            <indexterm index="fn" number="253" mergedindex="cp">
              tocdepth
              <r>
                counter
              </r>
            </indexterm>
          </findex>
          <cindex index="cp" spaces=" ">
            <indexterm index="cp" number="240">
              table of contents, sectioning numbers printed
            </indexterm>
          </cindex>
          <anchor name="sectioning-tocdepth">
            sectioning tocdepth
          </anchor>
          <anchor name="Sectioning_002ftocdepth">
            Sectioning/tocdepth
          </anchor>
          <para>
            Controls which sectioning units are listed in the table of contents. The setting
            <code>
              \setcounter
Default handler: &lbrace;
              tocdepth
Default handler: &rbrace;
Default handler: &lbrace;
              <var>
                level
              </var>
Default handler: &rbrace;
            </code>
             makes the sectioning units at
            <var>
              level
            </var>
             be the smallest ones listed (
            <pxref label="_005csetcounter">
              <xrefnodename>
                \setcounter
              </xrefnodename>
            </pxref>
            ). See the above table for the level numbers. For instance, if
            <code>
              tocdepth
            </code>
             is
Default handler: &nbsp;
            1 then the table of contents will list sections but not subsections.
Default handler: &latex;
Default handler: &textrsquo;
            s default
            <code>
              tocdepth
            </code>
             is
Default handler: &nbsp;
            3 in
            <file>
              article
            </file>
             class and
Default handler: &nbsp;
            2 in the
            <file>
              book
            </file>
             and
            <file>
              report
            </file>
             classes.
          </para>
        </tableitem>
      </tableentry>
    </ftable>
    <menu endspaces=" ">
      <menuentry>
        <menuleadingtext>
          *
        </menuleadingtext>
        <menunode>
          \part
        </menunode>
        <menuseparator>
          ::
        </menuseparator>
        <menudescription>
          <pre xml:space="preserve">
            Start a part.
          </pre>
        </menudescription>
      </menuentry>
      <menuentry>
        <menuleadingtext>
          *
        </menuleadingtext>
        <menunode>
          \chapter
        </menunode>
        <menuseparator>
          ::
        </menuseparator>
        <menudescription>
          <pre xml:space="preserve">
            Start a chapter.
          </pre>
        </menudescription>
      </menuentry>
      <menuentry>
        <menuleadingtext>
          *
        </menuleadingtext>
        <menunode>
          \section
        </menunode>
        <menuseparator>
          ::
        </menuseparator>
        <menudescription>
          <pre xml:space="preserve">
            Start a section.
          </pre>
        </menudescription>
      </menuentry>
      <menuentry>
        <menuleadingtext>
          *
        </menuleadingtext>
        <menunode>
          \subsection
        </menunode>
        <menuseparator>
          ::
        </menuseparator>
        <menudescription>
          <pre xml:space="preserve">
            Start a subsection.
          </pre>
        </menudescription>
      </menuentry>
      <menuentry>
        <menuleadingtext>
          *
        </menuleadingtext>
        <menunode>
          \subsubsection
          &
           \paragraph
          &
           \subparagraph
        </menunode>
        <menuseparator>
          ::
        </menuseparator>
        <menudescription>
          <pre xml:space="preserve">
            Lower divisions.
          </pre>
        </menudescription>
      </menuentry>
      <menuentry>
        <menuleadingtext>
          *
        </menuleadingtext>
        <menunode>
          \appendix
        </menunode>
        <menuseparator>
          ::
        </menuseparator>
        <menudescription>
          <pre xml:space="preserve">
            Start appendices.
          </pre>
        </menudescription>
      </menuentry>
      <menuentry>
        <menuleadingtext>
          *
        </menuleadingtext>
        <menunode>
          \frontmatter
          &
           \mainmatter
          &
           \backmatter
        </menunode>
        <menuseparator>
          ::
        </menuseparator>
        <menudescription>
          <pre xml:space="preserve">
            The three parts of a book.
          </pre>
        </menudescription>
      </menuentry>
      <menuentry>
        <menuleadingtext>
          *
        </menuleadingtext>
        <menunode>
          \
Default handler: &arobase;
          startsection
        </menunode>
        <menuseparator>
          ::
        </menuseparator>
        <menudescription>
          <pre xml:space="preserve">
            Sectional unit headings.
          </pre>
        </menudescription>
      </menuentry>
    </menu>
    <node name="_005cpart" spaces=" ">
      <nodename>
        \part
      </nodename>
      <nodenext automatic="on">
        \chapter
      </nodenext>
      <nodeup automatic="on">
        Sectioning
      </nodeup>
    </node>
    <section spaces=" ">
      <sectiontitle>
        <code>
          \part
        </code>
      </sectiontitle>
      <findex index="fn" spaces=" ">
        <indexterm index="fn" number="254" mergedindex="cp">
          \part
        </indexterm>
      </findex>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="241">
          part
        </indexterm>
      </cindex>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="242">
          sectioning, part
        </indexterm>
      </cindex>
      <para>
        Synopsis, one of:
      </para>
      <example endspaces=" ">
        <pre xml:space="preserve">
          \part
Default handler: &lbrace;
          <var>
            title
          </var>
Default handler: &rbrace;
           \part*
Default handler: &lbrace;
          <var>
            title
          </var>
Default handler: &rbrace;
           \part[
          <var>
            toc-title
          </var>
          ]
Default handler: &lbrace;
          <var>
            title
          </var>
Default handler: &rbrace;
        </pre>
      </example>
      <para>
        Start a document part. The standard
Default handler: &latex;
         classes
        <code>
          book
        </code>
        ,
        <code>
          report
        </code>
        , and
        <code>
          article
        </code>
        , all have this command.
      </para>
      <para>
        This produces a document part, in a book.
      </para>
      <example endspaces=" ">
        <pre xml:space="preserve">
          \part
Default handler: &lbrace;
          VOLUME I \\ PERSONAL MEMOIRS OF U.\ S.\ GRANT
Default handler: &rbrace;
           \chapter
Default handler: &lbrace;
          ANCESTRY--BIRTH--BOYHOOD.
Default handler: &rbrace;
           My family is American, and has been for generations, in all its branches, direct and collateral.
        </pre>
      </example>
      <para>
        In each standard class the
        <code>
          \part
        </code>
         command outputs a part number such as
        <samp>
          Part I
        </samp>
        , alone on its line, in boldface, and in large type. Then
Default handler: &latex;
         outputs
        <var>
          title
        </var>
        , also alone on its line, in bold and in even larger type. In class
        <code>
          book
        </code>
        , the
Default handler: &latex;
         default puts each part alone on its own page. If the book is two-sided then
Default handler: &latex;
         will skip a page if needed to have the new part on an odd-numbered page. In
        <code>
          report
        </code>
         it is again alone on a page, but
Default handler: &latex;
         won
Default handler: &textrsquo;
        t force it onto an odd-numbered page. In an
        <code>
          article
        </code>
Default handler: &latex;
         does not put it on a fresh page, but instead outputs the part number and part title onto the main document page.
      </para>
      <para>
        The
        <code>
          *
        </code>
Default handler: &nbsp;
        form shows
        <var>
          title
        </var>
         but it does not show the part number, does not increment the
        <code>
          part
        </code>
         counter, and produces no table of contents entry.
      </para>
      <para>
        The optional argument
        <var>
          toc-title
        </var>
         will appear as the part title in the table of contents (
        <pxref label="Table-of-contents-etc_002e">
          <xrefnodename>
            Table of contents etc.
          </xrefnodename>
        </pxref>
        ) and in running headers (
        <pxref label="Page-styles">
          <xrefnodename>
            Page styles
          </xrefnodename>
        </pxref>
        ). If it is not present then
        <var>
          title
        </var>
         will be there. This example puts a line break in
        <var>
          title
        </var>
         but omits the break in the table of contents.
      </para>
      <example endspaces=" ">
        <pre xml:space="preserve">
          \part[Up from the bottom; my life]
Default handler: &lbrace;
          Up from the bottom\\ my life
Default handler: &rbrace;
        </pre>
      </example>
      <para>
        For determining which sectional units are numbered and which appear in the table of contents, the level number of a part is
Default handler: &nbsp;
        -1 (
        <pxref label="Sectioning_002fsecnumdepth">
          <xrefnodename>
            Sectioning/secnumdepth
          </xrefnodename>
        </pxref>
        , and
        <ref label="Sectioning_002ftocdepth">
          <xrefnodename>
            Sectioning/tocdepth
          </xrefnodename>
        </ref>
        ).
      </para>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="243">
          <r>
            package
          </r>
          ,
          <code>
            indentfirst
          </code>
        </indexterm>
      </cindex>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="244">
          <code>
            indentfirst
          </code>
          <r>
            package
          </r>
        </indexterm>
      </cindex>
      <para>
        In the class
        <code>
          article
        </code>
        , if a paragraph immediately follows the part title then it is not indented. To get an indent you can use the package
        <code>
          indentfirst
        </code>
        .
      </para>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="245">
          <r>
            package
          </r>
          ,
          <code>
            titlesec
          </code>
        </indexterm>
      </cindex>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="246">
          <code>
            titlesec
          </code>
          <r>
            package
          </r>
        </indexterm>
      </cindex>
      <para>
        One package to change the behavior of
        <code>
          \part
        </code>
         is
        <code>
          titlesec
        </code>
        . See its documentation on CTAN.
      </para>
    </section>
    <node name="_005cchapter" spaces=" ">
      <nodename>
        \chapter
      </nodename>
      <nodenext automatic="on">
        \section
      </nodenext>
      <nodeprev automatic="on">
        \part
      </nodeprev>
      <nodeup automatic="on">
        Sectioning
      </nodeup>
    </node>
    <section spaces=" ">
      <sectiontitle>
        <code>
          \chapter
        </code>
      </sectiontitle>
      <findex index="fn" spaces=" ">
        <indexterm index="fn" number="255" mergedindex="cp">
          \chapter
        </indexterm>
      </findex>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="247">
          chapter
        </indexterm>
      </cindex>
      <para>
        Synopsis, one of:
      </para>
      <example endspaces=" ">
        <pre xml:space="preserve">
          \chapter
Default handler: &lbrace;
          <var>
            title
          </var>
Default handler: &rbrace;
           \chapter*
Default handler: &lbrace;
          <var>
            title
          </var>
Default handler: &rbrace;
           \chapter[
          <var>
            toc-title
          </var>
          ]
Default handler: &lbrace;
          <var>
            title
          </var>
Default handler: &rbrace;
        </pre>
      </example>
      <para>
        Start a chapter. The standard
Default handler: &latex;
         classes
        <code>
          book
        </code>
         and
        <code>
          report
        </code>
         have this command but
        <code>
          article
        </code>
         does not.
      </para>
      <para>
        This produces a chapter.
      </para>
      <example endspaces=" ">
        <pre xml:space="preserve">
          \chapter
Default handler: &lbrace;
          Loomings
Default handler: &rbrace;
           Call me Ishmael. Some years ago---never mind how long precisely---having little or no money in my purse, and nothing particular to interest me on shore, I thought I would sail about a little and see the watery part of the world.
        </pre>
      </example>
      <para>
        The
Default handler: &latex;
         default starts each chapter on a fresh page, an odd-numbered page if the document is two-sided. It produces a chapter number such as
        <samp>
          Chapter 1
        </samp>
         in large boldface type (the size is
        <code>
          \huge
        </code>
        ). It then puts
        <var>
          title
        </var>
         on a fresh line, in boldface type that is still larger (size
        <code>
          \Huge
        </code>
        ). It also increments the
        <code>
          chapter
        </code>
         counter, adds an entry to the table of contents (
        <pxref label="Table-of-contents-etc_002e">
          <xrefnodename>
            Table of contents etc.
          </xrefnodename>
        </pxref>
        ), and sets the running header information (
        <pxref label="Page-styles">
          <xrefnodename>
            Page styles
          </xrefnodename>
        </pxref>
        ).
      </para>
      <para>
        The
        <code>
          *
        </code>
Default handler: &nbsp;
        form shows
        <var>
          title
        </var>
         on a fresh line, in boldface. But it does not show the chapter number, does not increment the
        <code>
          chapter
        </code>
         counter, produces no table of contents entry, and does not affect the running header. (If you use the page style
        <code>
          headings
        </code>
         in a two-sided document then the header will be from the prior chapter.) This example illustrates.
      </para>
      <example endspaces=" ">
        <pre xml:space="preserve">
          \chapter*
Default handler: &lbrace;
          Preamble
Default handler: &rbrace;
        </pre>
      </example>
      <para>
        The optional argument
        <var>
          toc-title
        </var>
         will appear as the chapter title in the table of contents (
        <pxref label="Table-of-contents-etc_002e">
          <xrefnodename>
            Table of contents etc.
          </xrefnodename>
        </pxref>
        ) and in running headers (
        <pxref label="Page-styles">
          <xrefnodename>
            Page styles
          </xrefnodename>
        </pxref>
        ). If it is not present then
        <var>
          title
        </var>
         will be there. This shows the full name in the chapter title,
      </para>
      <example endspaces=" ">
        <pre xml:space="preserve">
          \chapter[Weyl]
Default handler: &lbrace;
          Hermann Klaus Hugo (Peter) Weyl (1885--1955)
Default handler: &rbrace;
        </pre>
      </example>
      <noindent/>
      <para>
        but only
        <samp>
          Weyl
        </samp>
         on the contents page. This puts a line break in the title but that doesn
Default handler: &textrsquo;
        t work well with running headers so it omits the break in the contents
      </para>
      <example endspaces=" ">
        <pre xml:space="preserve">
          \chapter[Given it all; my story]
Default handler: &lbrace;
          Given it all\\ my story
Default handler: &rbrace;
        </pre>
      </example>
      <para>
        For determining which sectional units are numbered and which appear in the table of contents, the level number of a chapter is
Default handler: &nbsp;
        0 (
        <pxref label="Sectioning_002fsecnumdepth">
          <xrefnodename>
            Sectioning/secnumdepth
          </xrefnodename>
        </pxref>
         and
        <pxref label="Sectioning_002ftocdepth">
          <xrefnodename>
            Sectioning/tocdepth
          </xrefnodename>
        </pxref>
        ).
      </para>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="248">
          <r>
            package
          </r>
          ,
          <code>
            indentfirst
          </code>
        </indexterm>
      </cindex>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="249">
          <code>
            indentfirst
          </code>
          <r>
            package
          </r>
        </indexterm>
      </cindex>
      <para>
        The paragraph that follows the chapter title is not indented, as is a standard typographical practice. To get an indent use the package
        <code>
          indentfirst
        </code>
        .
      </para>
      <para>
        You can change what is shown for the chapter number. To change it to something like
        <samp>
          Lecture 1
        </samp>
        , put in the preamble either
        <code>
          \renewcommand
Default handler: &lbrace;
          \chaptername
Default handler: &rbrace;
Default handler: &lbrace;
          Lecture
Default handler: &rbrace;
        </code>
         or this (
        <pxref label="_005cmakeatletter-_0026-_005cmakeatother">
          <xrefnodename>
            \makeatletter
            &
             \makeatother
          </xrefnodename>
        </pxref>
        ).
      </para>
      <example endspaces=" ">
        <pre xml:space="preserve">
          \makeatletter \renewcommand
Default handler: &lbrace;
          \
Default handler: &arobase;
          chapapp
Default handler: &rbrace;
Default handler: &lbrace;
          Lecture
Default handler: &rbrace;
           \makeatother
        </pre>
      </example>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="250">
          <r>
            package
          </r>
          ,
          <code>
            babel
          </code>
        </indexterm>
      </cindex>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="251">
          <code>
            babel
          </code>
          <r>
            package
          </r>
        </indexterm>
      </cindex>
      <noindent/>
      <para>
        To make this change because of the primary language for the document, see the package
        <code>
          babel
        </code>
        .
      </para>
      <para>
        In a two-sided document
Default handler: &latex;
         puts a chapter on odd-numbered page, if necessary leaving an even-numbered page that is blank except for any running headers. To make that page completely blank, see
Default handler: &nbsp;
        <ref label="_005cclearpage-_0026-_005ccleardoublepage">
          <xrefnodename>
            \clearpage
            &
             \cleardoublepage
          </xrefnodename>
        </ref>
        .
      </para>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="252">
          <r>
            package
          </r>
          ,
          <code>
            titlesec
          </code>
        </indexterm>
      </cindex>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="253">
          <code>
            titlesec
          </code>
          <r>
            package
          </r>
        </indexterm>
      </cindex>
      <para>
        To change the behavior of the
        <code>
          \chapter
        </code>
         command, you can copy its definition from the
Default handler: &latex;
         format file and make adjustments. But there are also many packages on CTAN that address this. One is
        <code>
          titlesec
        </code>
        . See its documentation, but the example below gives a sense of what it can do.
      </para>
      <example endspaces=" ">
        <pre xml:space="preserve">
          \usepackage
Default handler: &lbrace;
          titlesec
Default handler: &rbrace;
           % in preamble \titleformat
Default handler: &lbrace;
          \chapter
Default handler: &rbrace;
Default handler: &lbrace;
          \Huge\bfseries
Default handler: &rbrace;
           % format of title
Default handler: &lbrace;
Default handler: &rbrace;
           % label, such as 1.2 for a subsection
Default handler: &lbrace;
          0pt
Default handler: &rbrace;
           % length of separation between label and title
Default handler: &lbrace;
Default handler: &rbrace;
           % before-code hook
        </pre>
      </example>
      <noindent/>
      <para>
        This omits the chapter number
        <samp>
          Chapter 1
        </samp>
         from the page but unlike
        <code>
          \chapter*
        </code>
         it keeps the chapter in the table of contents and the running headers.
      </para>
    </section>
    <node name="_005csection" spaces=" ">
      <nodename>
        \section
      </nodename>
      <nodenext automatic="on">
        \subsection
      </nodenext>
      <nodeprev automatic="on">
        \chapter
      </nodeprev>
      <nodeup automatic="on">
        Sectioning
      </nodeup>
    </node>
    <section spaces=" ">
      <sectiontitle>
        <code>
          \section
        </code>
      </sectiontitle>
      <findex index="fn" spaces=" ">
        <indexterm index="fn" number="256" mergedindex="cp">
          \section
        </indexterm>
      </findex>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="254">
          section
        </indexterm>
      </cindex>
      <para>
        Synopsis, one of:
      </para>
      <example endspaces=" ">
        <pre xml:space="preserve">
          \section
Default handler: &lbrace;
          <var>
            title
          </var>
Default handler: &rbrace;
           \section*
Default handler: &lbrace;
          <var>
            title
          </var>
Default handler: &rbrace;
           \section[
          <var>
            toc-title
          </var>
          ]
Default handler: &lbrace;
          <var>
            title
          </var>
Default handler: &rbrace;
        </pre>
      </example>
      <para>
        Start a section. The standard
Default handler: &latex;
         classes
        <code>
          article
        </code>
        ,
        <code>
          book
        </code>
        , and
        <code>
          report
        </code>
         all have this command.
      </para>
      <para>
        This produces a section.
      </para>
      <example endspaces=" ">
        <pre xml:space="preserve">
          In this Part we tend to be more interested in the function, in the input-output behavior, than in the details of implementing that behavior. \section
Default handler: &lbrace;
          Turing machines
Default handler: &rbrace;
           Despite this desire to downplay implementation, we follow the approach of A~Turing that the first step toward defining the set of computable functions is to reflect on the details of what mechanisms can do.
        </pre>
      </example>
      <para>
        For the standard
Default handler: &latex;
         classes
        <code>
          book
        </code>
         and
        <code>
          report
        </code>
         the default output is like
        <samp>
          1.2
          <var>
            title
          </var>
        </samp>
         (for chapter
Default handler: &nbsp;
        1, section
Default handler: &nbsp;
        2), alone on its line and flush left, in boldface and a larger type (the type size is
        <code>
          \Large
        </code>
        ). The same holds in
        <code>
          article
        </code>
         except that there are no chapters in that class so it looks like
        <samp>
          2
          <var>
            title
          </var>
        </samp>
        .
      </para>
      <para>
        The
        <code>
          *
        </code>
Default handler: &nbsp;
        form shows
        <var>
          title
        </var>
        . But it does not show the section number, does not increment the
        <code>
          section
        </code>
         counter, produces no table of contents entry, and does not affect the running header. (If you use the page style
        <code>
          headings
        </code>
         in a two-sided document then the header will be from the prior section.)
      </para>
      <para>
        The optional argument
        <var>
          toc-title
        </var>
         will appear as the section title in the table of contents (
        <pxref label="Table-of-contents-etc_002e">
          <xrefnodename>
            Table of contents etc.
          </xrefnodename>
        </pxref>
        ) and in running headers (
        <pxref label="Page-styles">
          <xrefnodename>
            Page styles
          </xrefnodename>
        </pxref>
        ). If it is not present then
        <var>
          title
        </var>
         will be there. This shows the full name in the title of the section:
      </para>
      <example endspaces=" ">
        <pre xml:space="preserve">
          \section[Elizabeth~II]
Default handler: &lbrace;
          Elizabeth the Second, by the Grace of God of the United Kingdom, Canada and Her other Realms and Territories Queen, Head of the Commonwealth, Defender of the Faith.
Default handler: &rbrace;
        </pre>
      </example>
      <noindent/>
      <para>
        but only
        <samp>
          Elizabeth II
        </samp>
         on the contents page and in the headers. This has a line break in
        <var>
          title
        </var>
         but that does not work with headers so it is omitted from the contents and headers.
      </para>
      <example endspaces=" ">
        <pre xml:space="preserve">
          \section[Truth is, I cheated; my life story]
Default handler: &lbrace;
          Truth is, I cheated\\my life story
Default handler: &rbrace;
        </pre>
      </example>
      <para>
        For determining which sectional units are numbered and which appear in the table of contents, the level number of a section is
Default handler: &nbsp;
        1 (
        <pxref label="Sectioning_002fsecnumdepth">
          <xrefnodename>
            Sectioning/secnumdepth
          </xrefnodename>
        </pxref>
         and
        <pxref label="Sectioning_002ftocdepth">
          <xrefnodename>
            Sectioning/tocdepth
          </xrefnodename>
        </pxref>
        ).
      </para>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="255">
          <r>
            package
          </r>
          ,
          <code>
            indentfirst
          </code>
        </indexterm>
      </cindex>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="256">
          <code>
            indentfirst
          </code>
          <r>
            package
          </r>
        </indexterm>
      </cindex>
      <para>
        The paragraph that follows the section title is not indented, as is a standard typographical practice. One way to get an indent is to use the package
        <code>
          indentfirst
        </code>
        .
      </para>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="257">
          <r>
            package
          </r>
          ,
          <code>
            titlesec
          </code>
        </indexterm>
      </cindex>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="258">
          <code>
            titlesec
          </code>
          <r>
            package
          </r>
        </indexterm>
      </cindex>
      <para>
        In general, to change the behavior of the
        <code>
          \section
        </code>
         command, there are a number of options. One is the
        <code>
          \
Default handler: &arobase;
          startsection
        </code>
         command (
        <pxref label="_005c_0040startsection">
          <xrefnodename>
            \
Default handler: &arobase;
            startsection
          </xrefnodename>
        </pxref>
        ). There are also many packages on CTAN that address this, including
        <code>
          titlesec
        </code>
        . See the documentation but the example below gives a sense of what they can do.
      </para>
Default handler: <!-- c credit: egreg https://groups.google.com/forum/#!topic/comp.text.tex/tvc8oM5P4y4 -->
      <example endspaces=" ">
        <pre xml:space="preserve">
          \usepackage
Default handler: &lbrace;
          titlesec
Default handler: &rbrace;
           % in preamble \titleformat
Default handler: &lbrace;
          \section
Default handler: &rbrace;
Default handler: &lbrace;
          \normalfont\Large\bfseries
Default handler: &rbrace;
           % format of title
Default handler: &lbrace;
          \makebox[1pc][r]
Default handler: &lbrace;
          \thesection\hspace
Default handler: &lbrace;
          1pc
Default handler: &rbrace;
Default handler: &rbrace;
Default handler: &rbrace;
           % label
Default handler: &lbrace;
          0pt
Default handler: &rbrace;
           % length of separation between label and title
Default handler: &lbrace;
Default handler: &rbrace;
           % before-code hook \titlespacing*
Default handler: &lbrace;
          \section
Default handler: &rbrace;
Default handler: &lbrace;
          -1pc
Default handler: &rbrace;
Default handler: &lbrace;
          18pt
Default handler: &rbrace;
Default handler: &lbrace;
          10pt
Default handler: &rbrace;
          [10pc]
        </pre>
      </example>
      <noindent/>
      <para>
        That puts the section number in the margin.
      </para>
    </section>
    <node name="_005csubsection" spaces=" ">
      <nodename>
        \subsection
      </nodename>
      <nodenext automatic="on">
        \subsubsection
        &
         \paragraph
        &
         \subparagraph
      </nodenext>
      <nodeprev automatic="on">
        \section
      </nodeprev>
      <nodeup automatic="on">
        Sectioning
      </nodeup>
    </node>
    <section spaces=" ">
      <sectiontitle>
        <code>
          \subsection
        </code>
      </sectiontitle>
      <findex index="fn" spaces=" ">
        <indexterm index="fn" number="257" mergedindex="cp">
          \subsection
        </indexterm>
      </findex>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="259">
          subsection
        </indexterm>
      </cindex>
      <para>
        Synopsis, one of:
      </para>
      <example endspaces=" ">
        <pre xml:space="preserve">
          \subsection
Default handler: &lbrace;
          <var>
            title
          </var>
Default handler: &rbrace;
           \subsection*
Default handler: &lbrace;
          <var>
            title
          </var>
Default handler: &rbrace;
           \subsection[
          <var>
            toc-title
          </var>
          ]
Default handler: &lbrace;
          <var>
            title
          </var>
Default handler: &rbrace;
        </pre>
      </example>
      <para>
        Start a subsection. The standard
Default handler: &latex;
         classes
        <code>
          article
        </code>
        ,
        <code>
          book
        </code>
        , and
        <code>
          report
        </code>
         all have this command.
      </para>
      <para>
        This produces a subsection.
      </para>
      <example endspaces=" ">
        <pre xml:space="preserve">
          We will show that there are more functions than Turing machines and that therefore some functions have no associated machine. \subsection
Default handler: &lbrace;
          Cardinality
Default handler: &rbrace;
           We will begin with two paradoxes that dramatize the challenge to our intuition posed by comparing the sizes of infinite sets.
        </pre>
      </example>
      <para>
        For the standard
Default handler: &latex;
         classes
        <code>
          book
        </code>
         and
        <code>
          report
        </code>
         the default output is like
        <samp>
          1.2.3
          <var>
            title
          </var>
        </samp>
         (for chapter
Default handler: &nbsp;
        1, section
Default handler: &nbsp;
        2, subsection
Default handler: &nbsp;
        3), alone on its line and flush left, in boldface and a larger type (the type size is
        <code>
          \large
        </code>
        ). The same holds in
        <code>
          article
        </code>
         except that there are no chapters in that class so it looks like
        <samp>
          2.3
          <var>
            title
          </var>
        </samp>
        .
      </para>
      <para>
        The
        <code>
          *
        </code>
Default handler: &nbsp;
        form shows
        <var>
          title
        </var>
        . But it does not show the subsection number, does not increment the
        <code>
          subsection
        </code>
         counter, and produces no table of contents entry.
      </para>
      <para>
        The optional argument
        <var>
          toc-title
        </var>
         will appear as the subsection title in the table of contents (
        <pxref label="Table-of-contents-etc_002e">
          <xrefnodename>
            Table of contents etc.
          </xrefnodename>
        </pxref>
        ). If it is not present then
        <var>
          title
        </var>
         will be there. This shows the full text in the title of the subsection:
      </para>
      <example endspaces=" ">
        <pre xml:space="preserve">
          \subsection[$\alpha,\beta,\gamma$ paper]
Default handler: &lbrace;
          \textit
Default handler: &lbrace;
          The Origin of Chemical Elements
Default handler: &rbrace;
           by R.A.~Alpher, H.~Bethe, and G.~Gamow
Default handler: &rbrace;
        </pre>
      </example>
      <noindent/>
      <para>
        but only
        <samp>
          <u>
            03B1
          </u>
          ,
          <u>
            03B2
          </u>
          ,
          <u>
            03B3
          </u>
           paper
        </samp>
         on the contents page.
      </para>
      <para>
        For determining which sectional units are numbered and which appear in the table of contents, the level number of a subsection is
Default handler: &nbsp;
        2 (
        <pxref label="Sectioning_002fsecnumdepth">
          <xrefnodename>
            Sectioning/secnumdepth
          </xrefnodename>
        </pxref>
         and
        <pxref label="Sectioning_002ftocdepth">
          <xrefnodename>
            Sectioning/tocdepth
          </xrefnodename>
        </pxref>
        ).
      </para>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="260">
          <r>
            package
          </r>
          ,
          <code>
            indentfirst
          </code>
        </indexterm>
      </cindex>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="261">
          <code>
            indentfirst
          </code>
          <r>
            package
          </r>
        </indexterm>
      </cindex>
      <para>
        The paragraph that follows the subsection title is not indented, as is a standard typographical practice. One way to get an indent is to use the package
        <code>
          indentfirst
        </code>
        .
      </para>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="262">
          <r>
            package
          </r>
          ,
          <code>
            titlesec
          </code>
        </indexterm>
      </cindex>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="263">
          <code>
            titlesec
          </code>
          <r>
            package
          </r>
        </indexterm>
      </cindex>
      <para>
        There are a number of ways to change the behavior of the
        <code>
          \subsection
        </code>
         command. One is the
        <code>
          \
Default handler: &arobase;
          startsection
        </code>
         command (
        <pxref label="_005c_0040startsection">
          <xrefnodename>
            \
Default handler: &arobase;
            startsection
          </xrefnodename>
        </pxref>
        ). There are also many packages on CTAN that address this, including
        <code>
          titlesec
        </code>
        . See the documentation but the example below gives a sense of what they can do.
      </para>
      <example endspaces=" ">
        <pre xml:space="preserve">
          \usepackage
Default handler: &lbrace;
          titlesec
Default handler: &rbrace;
           % in preamble \titleformat
Default handler: &lbrace;
          \subsection
Default handler: &rbrace;
          [runin]
Default handler: &lbrace;
          \normalfont\normalsize\bfseries
Default handler: &rbrace;
           % format of the title
Default handler: &lbrace;
          \thesubsection
Default handler: &rbrace;
           % label
Default handler: &lbrace;
          0.6em
Default handler: &rbrace;
           % space between label and title
Default handler: &lbrace;
Default handler: &rbrace;
           % before-code hook
        </pre>
      </example>
      <noindent/>
      <para>
        That puts the subsection number and
        <var>
          title
        </var>
         in the first line of text.
      </para>
    </section>
    <node name="_005csubsubsection-_0026-_005cparagraph-_0026-_005csubparagraph" spaces=" ">
      <nodename>
        \subsubsection
        &
         \paragraph
        &
         \subparagraph
      </nodename>
      <nodenext automatic="on">
        \appendix
      </nodenext>
      <nodeprev automatic="on">
        \subsection
      </nodeprev>
      <nodeup automatic="on">
        Sectioning
      </nodeup>
    </node>
    <section spaces=" ">
      <sectiontitle>
        <code>
          \subsubsection
        </code>
        ,
        <code>
          \paragraph
        </code>
        ,
        <code>
          \subparagraph
        </code>
      </sectiontitle>
      <anchor name="_005csubsubsection">
        \subsubsection
      </anchor>
      <findex index="fn" spaces=" ">
        <indexterm index="fn" number="258" mergedindex="cp">
          \subsubsection
        </indexterm>
      </findex>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="264">
          subsubsection
        </indexterm>
      </cindex>
Default handler: <!-- c -->
      <anchor name="_005cparagraph">
        \paragraph
      </anchor>
      <findex index="fn" spaces=" ">
        <indexterm index="fn" number="259" mergedindex="cp">
          \paragraph
        </indexterm>
      </findex>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="265">
          paragraph
        </indexterm>
      </cindex>
Default handler: <!-- c -->
      <anchor name="_005csubparagraph">
        \subparagraph
      </anchor>
      <findex index="fn" spaces=" ">
        <indexterm index="fn" number="260" mergedindex="cp">
          \subparagraph
        </indexterm>
      </findex>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="266">
          subparagraph
        </indexterm>
      </cindex>
      <para>
        Synopsis, one of:
      </para>
      <example endspaces=" ">
        <pre xml:space="preserve">
          \subsubsection
Default handler: &lbrace;
          <var>
            title
          </var>
Default handler: &rbrace;
           \subsubsection*
Default handler: &lbrace;
          <var>
            title
          </var>
Default handler: &rbrace;
           \subsubsection[
          <var>
            toc-title
          </var>
          ]
Default handler: &lbrace;
          <var>
            title
          </var>
Default handler: &rbrace;
        </pre>
      </example>
      <noindent/>
      <para>
        or one of:
      </para>
      <example endspaces=" ">
        <pre xml:space="preserve">
          \paragraph
Default handler: &lbrace;
          <var>
            title
          </var>
Default handler: &rbrace;
           \paragraph*
Default handler: &lbrace;
          <var>
            title
          </var>
Default handler: &rbrace;
           \paragraph[
          <var>
            toc-title
          </var>
          ]
Default handler: &lbrace;
          <var>
            title
          </var>
Default handler: &rbrace;
        </pre>
      </example>
      <noindent/>
      <para>
        or one of:
      </para>
      <example endspaces=" ">
        <pre xml:space="preserve">
          \subparagraph
Default handler: &lbrace;
          <var>
            title
          </var>
Default handler: &rbrace;
           \subparagraph*
Default handler: &lbrace;
          <var>
            title
          </var>
Default handler: &rbrace;
           \subparagraph[
          <var>
            toc-title
          </var>
          ]
Default handler: &lbrace;
          <var>
            title
          </var>
Default handler: &rbrace;
        </pre>
      </example>
      <para>
        Start a subsubsection, paragraph, or subparagraph. The standard
Default handler: &latex;
         classes
        <code>
          article
        </code>
        ,
        <code>
          book
        </code>
        , and
        <code>
          report
        </code>
         all have these commands, although they are not commonly used.
      </para>
      <para>
        This produces a subsubsection.
      </para>
      <example endspaces=" ">
        <pre xml:space="preserve">
          \subsubsection
Default handler: &lbrace;
          Piston ring compressors: structural performance
Default handler: &rbrace;
           Provide exterior/interior wall cladding assemblies capable of withstanding the effects of load and stresses from consumer-grade gasoline engine piston rings.
        </pre>
      </example>
      <para>
        The default output of each of the three does not change over the standard
Default handler: &latex;
         classes
        <code>
          article
        </code>
        ,
        <code>
          book
        </code>
        , and
        <code>
          report
        </code>
        . For
        <code>
          \subsubsection
        </code>
         the
        <var>
          title
        </var>
         is alone on its line, in boldface and normal size type. For
        <code>
          \paragraph
        </code>
         the
        <var>
          title
        </var>
         is inline with the text, not indented, in boldface and normal size type. For
        <code>
          \subparagraph
        </code>
         the
        <var>
          title
        </var>
         is inline with the text, with a paragraph indent, in boldface and normal size type (Because an
        <code>
          article
        </code>
         has no chapters its subsubsections are numbered and so it looks like
        <samp>
          1.2.3
          <var>
            title
          </var>
        </samp>
        , for section
Default handler: &nbsp;
        1, subsection
Default handler: &nbsp;
        2, and subsubsection
Default handler: &nbsp;
        3. The other two divisions are not numbered.)
      </para>
      <para>
        The
        <code>
          *
        </code>
Default handler: &nbsp;
        form shows
        <var>
          title
        </var>
        . But it does not increment the associated counter and produces no table of contents entry (and does not show the number for
        <code>
          \subsubsection
        </code>
        ).
      </para>
      <para>
        The optional argument
        <var>
          toc-title
        </var>
         will appear as the division title in the table of contents (
        <pxref label="Table-of-contents-etc_002e">
          <xrefnodename>
            Table of contents etc.
          </xrefnodename>
        </pxref>
        ). If it is not present then
        <var>
          title
        </var>
         will be there.
      </para>
      <para>
        For determining which sectional units are numbered and which appear in the table of contents, the level number of a subsubsection is
Default handler: &nbsp;
        3, of a paragraph is
Default handler: &nbsp;
        4, and of a subparagraph is
Default handler: &nbsp;
        5 (
        <pxref label="Sectioning_002fsecnumdepth">
          <xrefnodename>
            Sectioning/secnumdepth
          </xrefnodename>
        </pxref>
         and
        <pxref label="Sectioning_002ftocdepth">
          <xrefnodename>
            Sectioning/tocdepth
          </xrefnodename>
        </pxref>
        ).
      </para>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="267">
          <r>
            package
          </r>
          ,
          <code>
            indentfirst
          </code>
        </indexterm>
      </cindex>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="268">
          <code>
            indentfirst
          </code>
          <r>
            package
          </r>
        </indexterm>
      </cindex>
      <para>
        The paragraph that follows the subsubsection title is not indented, as is a standard typographical practice. One way to get an indent is to use the package
        <code>
          indentfirst
        </code>
        .
      </para>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="269">
          <r>
            package
          </r>
          ,
          <code>
            titlesec
          </code>
        </indexterm>
      </cindex>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="270">
          <code>
            titlesec
          </code>
          <r>
            package
          </r>
        </indexterm>
      </cindex>
      <para>
        There are a number of ways to change the behavior of the these commands. One is the
        <code>
          \
Default handler: &arobase;
          startsection
        </code>
         command (
        <pxref label="_005c_0040startsection">
          <xrefnodename>
            \
Default handler: &arobase;
            startsection
          </xrefnodename>
        </pxref>
        ). There are also many packages on CTAN that address this, including
        <code>
          titlesec
        </code>
        . See the documentation on CTAN.
      </para>
    </section>
    <node name="_005cappendix" spaces=" ">
      <nodename>
        \appendix
      </nodename>
      <nodenext automatic="on">
        \frontmatter
        &
         \mainmatter
        &
         \backmatter
      </nodenext>
      <nodeprev automatic="on">
        \subsubsection
        &
         \paragraph
        &
         \subparagraph
      </nodeprev>
      <nodeup automatic="on">
        Sectioning
      </nodeup>
    </node>
    <section spaces=" ">
      <sectiontitle>
        <code>
          \appendix
        </code>
      </sectiontitle>
      <findex index="fn" spaces=" ">
        <indexterm index="fn" number="261" mergedindex="cp">
          \appendix
        </indexterm>
      </findex>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="271">
          appendix
        </indexterm>
      </cindex>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="272">
          appendices
        </indexterm>
      </cindex>
      <para>
        Synopsis:
      </para>
      <example endspaces=" ">
        <pre xml:space="preserve">
          \appendix
        </pre>
      </example>
      <para>
        This does not directly produce any output. But in a
        <code>
          book
        </code>
         or
        <code>
          report
        </code>
         document it declares that subsequent
        <code>
          \chapter
        </code>
         commands start an appendix. In an article it does the same, for
        <code>
          \section
        </code>
         commands. It also resets the
        <code>
          chapter
        </code>
         and
        <code>
          section
        </code>
         counters to
Default handler: &nbsp;
        0 in a book or report, and in an article resets the
        <code>
          section
        </code>
         and
        <code>
          subsection
        </code>
         counters.
      </para>
      <para>
        In this book
      </para>
      <example endspaces=" ">
        <pre xml:space="preserve">
          \chapter
Default handler: &lbrace;
          One
Default handler: &rbrace;
           ... \chapter
Default handler: &lbrace;
          Two
Default handler: &rbrace;
           ... ... \appendix \chapter
Default handler: &lbrace;
          Three
Default handler: &rbrace;
           ... \chapter
Default handler: &lbrace;
          Four
Default handler: &rbrace;
           ...
        </pre>
      </example>
      <noindent/>
      <para>
        the first two will generate output numbered
        <samp>
          Chapter 1
        </samp>
         and
        <samp>
          Chapter 2
        </samp>
        . After the
        <code>
          \appendix
        </code>
         the numbering will be
        <samp>
          Appendix A
        </samp>
         and
        <samp>
          Appendix B
        </samp>
        .
        <xref label="Larger-book-template">
          <xrefnodename>
            Larger book template
          </xrefnodename>
        </xref>
        , for another example.
      </para>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="273">
          <r>
            package
          </r>
          ,
          <code>
            appendix
          </code>
        </indexterm>
      </cindex>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="274">
          <code>
            appendix
          </code>
          <r>
            package
          </r>
        </indexterm>
      </cindex>
      <para>
        The
        <code>
          appendix
        </code>
         package adds the command
        <code>
          \appendixpage
        </code>
         to put a separate
        <samp>
          Appendices
        </samp>
         in the document body before the first appendix, and the command
        <code>
          \addappheadtotoc
        </code>
         to do the same in the table of contents. You can reset the name
        <samp>
          Appendices
        </samp>
         with a command like
        <code>
          \renewcommand
Default handler: &lbrace;
          \appendixname
Default handler: &rbrace;
Default handler: &lbrace;
          Specification
Default handler: &rbrace;
        </code>
        , as well as a number of other features. See the documentation on CTAN.
      </para>
    </section>
    <node name="_005cfrontmatter-_0026-_005cmainmatter-_0026-_005cbackmatter" spaces=" ">
      <nodename>
        \frontmatter
        &
         \mainmatter
        &
         \backmatter
      </nodename>
      <nodenext automatic="on">
        \
Default handler: &arobase;
        startsection
      </nodenext>
      <nodeprev automatic="on">
        \appendix
      </nodeprev>
      <nodeup automatic="on">
        Sectioning
      </nodeup>
    </node>
    <section spaces=" ">
      <sectiontitle>
        <code>
          \frontmatter
        </code>
        ,
        <code>
          \mainmatter
        </code>
        ,
        <code>
          \backmatter
        </code>
      </sectiontitle>
      <anchor name="_005cfrontmatter">
        \frontmatter
      </anchor>
      <findex index="fn" spaces=" ">
        <indexterm index="fn" number="262" mergedindex="cp">
          \frontmatter
        </indexterm>
      </findex>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="275">
          book, front matter
        </indexterm>
      </cindex>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="276">
          front matter of a book
        </indexterm>
      </cindex>
Default handler: <!-- c -->
      <anchor name="_005cmainmatter">
        \mainmatter
      </anchor>
      <findex index="fn" spaces=" ">
        <indexterm index="fn" number="263" mergedindex="cp">
          \mainmatter
        </indexterm>
      </findex>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="277">
          book, main matter
        </indexterm>
      </cindex>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="278">
          main matter of a book
        </indexterm>
      </cindex>
Default handler: <!-- c -->
      <anchor name="_005cbackmatter">
        \backmatter
      </anchor>
      <findex index="fn" spaces=" ">
        <indexterm index="fn" number="264" mergedindex="cp">
          \backmatter
        </indexterm>
      </findex>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="279">
          book, back matter
        </indexterm>
      </cindex>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="280">
          book, end matter
        </indexterm>
      </cindex>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="281">
          back matter of a book
        </indexterm>
      </cindex>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="282">
          end matter of a book
        </indexterm>
      </cindex>
      <para>
        Synopsis, one or more of:
      </para>
      <example endspaces=" ">
        <pre xml:space="preserve">
          \frontmatter ... \mainmatter ... \backmatter ...
        </pre>
      </example>
      <para>
        Format a
        <code>
          book
        </code>
         class document differently according to which part of the document is being produced. All three commands are optional.
      </para>
      <para>
        Traditionally, a book
Default handler: &textrsquo;
        s front matter contains such things as the title page, an abstract, a table of contents, a preface, a list of notations, a list of figures, and a list of tables. (Some of these front matter pages, such as the title page, are traditionally not numbered.) The back matter may contain such things as a glossary, notes, a bibliography, and an index.
      </para>
      <para>
        The
        <code>
          \frontmatter
        </code>
         command makes the pages numbered in lowercase roman, and makes chapters not numbered, although each chapter
Default handler: &textrsquo;
        s title appears in the table of contents; if you use other sectioning commands here, use the
        <code>
          *
        </code>
        -version (
        <pxref label="Sectioning">
          <xrefnodename>
            Sectioning
          </xrefnodename>
        </pxref>
        ).
      </para>
      <para>
        The
        <code>
          \mainmatter
        </code>
         command changes the behavior back to the expected version, and resets the page number.
      </para>
      <para>
        The
        <code>
          \backmatter
        </code>
         command leaves the page numbering alone but switches the chapters back to being not numbered.
      </para>
      <para>
        <xref label="Larger-book-template">
          <xrefnodename>
            Larger book template
          </xrefnodename>
        </xref>
        , for an example using these three commands.
      </para>
    </section>
    <node name="_005c_0040startsection" spaces=" ">
      <nodename>
        \
Default handler: &arobase;
        startsection
      </nodename>
      <nodeprev automatic="on">
        \frontmatter
        &
         \mainmatter
        &
         \backmatter
      </nodeprev>
      <nodeup automatic="on">
        Sectioning
      </nodeup>
    </node>
    <section spaces=" ">
      <sectiontitle>
        <code>
          \
Default handler: &arobase;
          startsection
        </code>
        : Typesetting sectional unit headings
      </sectiontitle>
      <findex index="fn" spaces=" ">
        <indexterm index="fn" number="265" mergedindex="cp">
          \
Default handler: &arobase;
          startsection
        </indexterm>
      </findex>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="283">
          section, redefining
        </indexterm>
      </cindex>
      <para>
        Synopsis:
      </para>
      <example endspaces=" ">
        <pre xml:space="preserve">
          \
Default handler: &arobase;
          startsection
Default handler: &lbrace;
          <var>
            name
          </var>
Default handler: &rbrace;
Default handler: &lbrace;
          <var>
            level
          </var>
Default handler: &rbrace;
Default handler: &lbrace;
          <var>
            indent
          </var>
Default handler: &rbrace;
Default handler: &lbrace;
          <var>
            beforeskip
          </var>
Default handler: &rbrace;
Default handler: &lbrace;
          <var>
            afterskip
          </var>
Default handler: &rbrace;
Default handler: &lbrace;
          <var>
            style
          </var>
Default handler: &rbrace;
        </pre>
      </example>
      <para>
        Used to help redefine the behavior of commands that start sectioning divisions such as
        <code>
          \section
        </code>
         or
        <code>
          \subsection
        </code>
        .
      </para>
      <para>
        The
        <code>
          titlesec
        </code>
         package makes manipulation of sectioning easier. Further, while most requirements for sectioning commands can be satisfied with
        <code>
          \
Default handler: &arobase;
          startsection
        </code>
        , some cannot. For instance, in the standard
Default handler: &latex;
        <code>
          book
        </code>
         and
        <code>
          report
        </code>
         classes the commands
        <code>
          \chapter
        </code>
         and
        <code>
          \report
        </code>
         are not constructed using this. To make such a command you may want to use the
        <code>
          \secdef
        </code>
         command.
Default handler: <!-- c xx define, and make a cross reference to, secdef. -->
      </para>
      <para>
        The
        <code>
          \
Default handler: &arobase;
          startsection
        </code>
         macro is used like this:
      </para>
      <example endspaces=" ">
        <pre xml:space="preserve">
          \
Default handler: &arobase;
          startsection
Default handler: &lbrace;
          <var>
            name
          </var>
Default handler: &rbrace;
Default handler: &lbrace;
          <var>
            level
          </var>
Default handler: &rbrace;
Default handler: &lbrace;
          <var>
            indent
          </var>
Default handler: &rbrace;
Default handler: &lbrace;
          <var>
            beforeskip
          </var>
Default handler: &rbrace;
Default handler: &lbrace;
          <var>
            afterskip
          </var>
Default handler: &rbrace;
Default handler: &lbrace;
          <var>
            style
          </var>
Default handler: &rbrace;
          *[
          <var>
            toctitle
          </var>
          ]
Default handler: &lbrace;
          <var>
            title
          </var>
Default handler: &rbrace;
        </pre>
      </example>
      <noindent/>
      <para>
        so that issuing
      </para>
      <example endspaces=" ">
        <pre xml:space="preserve">
          \renewcommand
Default handler: &lbrace;
          \section
Default handler: &rbrace;
Default handler: &lbrace;
          \
Default handler: &arobase;
          startsection
Default handler: &lbrace;
          <var>
            name
          </var>
Default handler: &rbrace;
Default handler: &lbrace;
          <var>
            level
          </var>
Default handler: &rbrace;
Default handler: &lbrace;
          <var>
            indent
          </var>
Default handler: &rbrace;
Default handler: &lbrace;
          <var>
            beforeskip
          </var>
Default handler: &rbrace;
Default handler: &lbrace;
          <var>
            afterskip
          </var>
Default handler: &rbrace;
Default handler: &lbrace;
          <var>
            style
          </var>
Default handler: &rbrace;
Default handler: &rbrace;
        </pre>
      </example>
      <noindent/>
      <para>
        redefines
        <code>
          \section
        </code>
         while keeping its standard calling form
        <code>
          \section*[
          <var>
            toctitle
          </var>
          ]
Default handler: &lbrace;
          <var>
            title
          </var>
Default handler: &rbrace;
        </code>
         (in which, as a reminder, the star
Default handler: &nbsp;
        <code>
          *
        </code>
         is optional).
        <xref label="Sectioning">
          <xrefnodename>
            Sectioning
          </xrefnodename>
        </xref>
        . This implies that when you write a command like
        <code>
          \renewcommand
Default handler: &lbrace;
          \section
Default handler: &rbrace;
Default handler: &lbrace;
          ...
Default handler: &rbrace;
        </code>
        , the
        <code>
          \
Default handler: &arobase;
          startsection
Default handler: &lbrace;
          ...
Default handler: &rbrace;
        </code>
         must come last in the definition. See the examples below.
      </para>
      <table commandarg="var" spaces=" " endspaces=" ">
        <beforefirstitem/>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="var">
                name
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <anchor name="startsection-name">
              startsection name
            </anchor>
            <anchor name="_005c_0040startsection_002fname">
              \
Default handler: &arobase;
              startsection/name
            </anchor>
            <para>
              Name of the counter used to number the sectioning header. This counter must be defined separately. Most commonly this is either
              <code>
                section
              </code>
              ,
              <code>
                subsection
              </code>
              , or
              <code>
                paragraph
              </code>
              . Although in those cases the counter name is the same as the sectioning command itself, you don
Default handler: &textrsquo;
              t have to use the same name.
            </para>
            <para>
              Then
              <code>
                \the
              </code>
              <var>
                name
              </var>
               displays the title number and
              <code>
                \
              </code>
              <var>
                name
              </var>
              <code>
                mark
              </code>
               is for the page headers. See the third example below.
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="var">
                level
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <anchor name="startsection-level">
              startsection level
            </anchor>
            <anchor name="_005c_0040startsection_002flevel">
              \
Default handler: &arobase;
              startsection/level
            </anchor>
            <para>
              An integer giving the depth of the sectioning command.
              <xref label="Sectioning">
                <xrefnodename>
                  Sectioning
                </xrefnodename>
              </xref>
              , for the list of standard level numbers.
            </para>
            <para>
              If
              <var>
                level
              </var>
               is less than or equal to the value of the counter
              <code>
                secnumdepth
              </code>
               then titles for this sectioning command will be numbered (
              <pxref label="Sectioning_002fsecnumdepth">
                <xrefnodename>
                  Sectioning/secnumdepth
                </xrefnodename>
              </pxref>
              ). For instance, if
              <code>
                secnumdepth
              </code>
               is 1 in an
              <code>
                article
              </code>
               then the command
              <code>
                \section
Default handler: &lbrace;
                Introduction
Default handler: &rbrace;
              </code>
               will produce output like
Default handler: &textldquo;
              1 Introduction
Default handler: &textrdquo;
               while
              <code>
                \subsection
Default handler: &lbrace;
                Discussion
Default handler: &rbrace;
              </code>
               will produce output like
Default handler: &textldquo;
              Discussion
Default handler: &textrdquo;
              , without the number prefix.
            </para>
            <para>
              If
              <var>
                level
              </var>
               is less than or equal to the value of the counter
              <var>
                tocdepth
              </var>
               then the table of contents will have an entry for this sectioning unit (
              <pxref label="Sectioning_002ftocdepth">
                <xrefnodename>
                  Sectioning/tocdepth
                </xrefnodename>
              </pxref>
              ). For instance, in an
              <code>
                article
              </code>
              , if
              <var>
                tocdepth
              </var>
               is 1 then the table of contents will list sections but not subsections.
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="var">
                indent
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <anchor name="startsection-indent">
              startsection indent
            </anchor>
            <anchor name="_005c_0040startsection_002findent">
              \
Default handler: &arobase;
              startsection/indent
            </anchor>
            <para>
              A length giving the indentation of all of the title lines with respect to the left margin. To have the title flush with the margin use
              <code>
                0pt
              </code>
              . A negative indentation such as
              <code>
                -\parindent
              </code>
               will move the title into the left margin.
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="var">
                beforeskip
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <anchor name="startsection-beforeskip">
              startsection beforeskip
            </anchor>
            <anchor name="_005c_0040startsection_002fbeforeskip">
              \
Default handler: &arobase;
              startsection/beforeskip
            </anchor>
            <para>
              The absolute value of this length is the amount of vertical space that is inserted before this sectioning unit
Default handler: &textrsquo;
              s title. This space will be discarded if the sectioning unit happens to start at the beginning of a page. If this number is negative then the first paragraph following the header is not indented; if it is non-negative then the first paragraph is indented. (Example: the negative of
              <code>
                1pt plus 2pt minus 3pt
              </code>
               is
              <code>
                -1pt plus -2pt minus -3pt
              </code>
              .)
            </para>
            <para>
              For example, if
              <var>
                beforeskip
              </var>
               is
              <code>
                -3.5ex plus -1ex minus -0.2ex
              </code>
               then to start the new sectioning unit,
Default handler: &latex;
               will add about 3.5 times the height of a letter x in vertical space, and the first paragraph in the section will not be indented. Using a rubber length, with
              <code>
                plus
              </code>
               and
              <code>
                minus
              </code>
              , is good practice here since it gives
Default handler: &latex;
               more flexibility in making up the page (
              <pxref label="Lengths">
                <xrefnodename>
                  Lengths
                </xrefnodename>
              </pxref>
              ).
            </para>
            <para>
              The full accounting of the vertical space between the baseline of the line prior to this sectioning unit
Default handler: &textrsquo;
              s header and the baseline of the header is that it is the sum of the
              <code>
                \parskip
              </code>
               of the text font, the
              <code>
                \baselineskip
              </code>
               of the title font, and the absolute value of the
              <var>
                beforeskip
              </var>
              . This space is typically rubber so it may stretch or shrink. (If the sectioning unit starts on a fresh page so that the vertical space is discarded then the baseline of the header text will be where
Default handler: &latex;
               would put the baseline of the first text line on that page.)
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="var">
                afterskip
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <anchor name="startsection-afterskip">
              startsection afterskip
            </anchor>
            <anchor name="_005c_0040startsection_002fafterskip">
              \
Default handler: &arobase;
              startsection/afterskip
            </anchor>
            <para>
              This is a length. If
              <var>
                afterskip
              </var>
               is non-negative then this is the vertical space inserted after the sectioning unit
Default handler: &textrsquo;
              s title header. If it is negative then the title header becomes a run-in header, so that it becomes part of the next paragraph. In this case the absolute value of the length gives the horizontal space between the end of the title and the beginning of the following paragraph. (Note that the negative of
              <code>
                1pt plus 2pt minus 3pt
              </code>
               is
              <code>
                -1pt plus -2pt minus -3pt
              </code>
              .)
            </para>
            <para>
              As with
              <var>
                beforeskip
              </var>
              , using a rubber length, with
              <code>
                plus
              </code>
               and
              <code>
                minus
              </code>
               components, is good practice here since it gives
Default handler: &latex;
               more flexibility in putting together the page.
            </para>
            <para>
              If
              <code>
                afterskip
              </code>
               is non-negative then the full accounting of the vertical space between the baseline of the sectioning unit
Default handler: &textrsquo;
              s header and the baseline of the first line of the following paragraph is that it is the sum of the
              <code>
                \parskip
              </code>
               of the title font, the
              <code>
                \baselineskip
              </code>
               of the text font, and the value of
              <var>
                after
              </var>
              . That space is typically rubber so it may stretch or shrink. (Note that because the sign of
              <code>
                afterskip
              </code>
               changes the sectioning unit header
Default handler: &textrsquo;
              s from standalone to run-in, you cannot use a negative
              <code>
                afterskip
              </code>
               to cancel part of the
              <code>
                \parskip
              </code>
              .)
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="var">
                style
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <anchor name="startsection-style">
              startsection style
            </anchor>
            <anchor name="_005c_0040startsection_002fstyle">
              \
Default handler: &arobase;
              startsection/style
            </anchor>
            <para>
              Controls the styling of the title. See the examples below. Typical commands to use here are
              <code>
                \centering
              </code>
              ,
              <code>
                \raggedright
              </code>
              ,
              <code>
                \normalfont
              </code>
              ,
              <code>
                \hrule
              </code>
              , or
              <code>
                \newpage
              </code>
              . The last command in
              <var>
                style
              </var>
               may be one that takes one argument, such as
              <code>
                \MakeUppercase
              </code>
               or
              <code>
                \fbox
              </code>
               that takes one argument. The section title will be supplied as the argument to this command. For instance, setting
              <var>
                style
              </var>
               to
              <code>
                \bfseries\MakeUppercase
              </code>
               would produce titles that are bold and uppercase.
            </para>
          </tableitem>
        </tableentry>
      </table>
      <para>
        These are
Default handler: &latex;
Default handler: &textrsquo;
        s defaults for the first three sectioning units that are defined with
        <code>
          \
Default handler: &arobase;
          startsection
        </code>
        , for the
        <file>
          article
        </file>
        ,
        <file>
          book
        </file>
        , and
        <file>
          report
        </file>
         classes.
      </para>
      <itemize commandarg="bullet" automaticcommandarg="on" endspaces=" ">
        <itemprepend>
          <formattingcommand command="bullet" automatic="on"/>
        </itemprepend>
        <listitem>
          <prependDefault handler: &bullet;
/>
          <para>
            For
            <code>
              section
            </code>
            :
            <var>
              level
            </var>
             is 1,
            <var>
              indent
            </var>
             is 0
            <dmn>
              pt
            </dmn>
            ,
            <var>
              beforeskip
            </var>
             is
            <code>
              -3.5ex plus -1ex minus -0.2ex
            </code>
            ,
            <var>
              afterskip
            </var>
             is
            <code>
              2.3ex plus 0.2ex
            </code>
            , and
            <var>
              style
            </var>
             is
            <code>
              \normalfont\Large\bfseries
            </code>
            .
          </para>
        </listitem>
        <listitem>
          <prependDefault handler: &bullet;
/>
          <para>
            For
            <code>
              subsection
            </code>
            :
            <var>
              level
            </var>
             is 2,
            <var>
              indent
            </var>
             is 0
            <dmn>
              pt
            </dmn>
            ,
            <var>
              beforeskip
            </var>
             is
            <code>
              -3.25ex plus -1ex minus
              <w>
                -0.2ex
              </w>
            </code>
            ,
            <var>
              afterskip
            </var>
             is
            <code>
              1.5ex plus 0.2ex
            </code>
            , and
            <var>
              style
            </var>
             is
            <code>
              \normalfont\large\bfseries
            </code>
            .
          </para>
        </listitem>
        <listitem>
          <prependDefault handler: &bullet;
/>
          <raggedright endspaces=" ">
            <para>
              For
              <code>
                subsubsection
              </code>
              :
              <var>
                level
              </var>
               is 3,
              <var>
                indent
              </var>
               is 0
              <dmn>
                pt
              </dmn>
              ,
              <var>
                beforeskip
              </var>
               is
              <code>
                -3.25ex plus -1ex minus -0.2ex
              </code>
              ,
              <var>
                afterskip
              </var>
               is
              <code>
                1.5ex plus 0.2ex
              </code>
              , and
              <var>
                style
              </var>
               is
              <code>
                \normalfont\normalsize\bfseries
              </code>
              .
            </para>
          </raggedright>
        </listitem>
      </itemize>
      <para>
        Some examples follow. These go either in a package or class file or in the preamble of a
Default handler: &latex;
         document. If you put them in the preamble they must go between a
        <code>
          \makeatletter
        </code>
         command and a
        <code>
          \makeatother
        </code>
        . (Probably the error message
        <code>
          You can't use `\spacefactor' in vertical mode.
        </code>
         means that you forgot this.)
        <xref label="_005cmakeatletter-_0026-_005cmakeatother">
          <xrefnodename>
            \makeatletter
            &
             \makeatother
          </xrefnodename>
        </xref>
        .
      </para>
      <para>
        This will put section titles in large boldface type, centered. It says
        <code>
          \renewcommand
        </code>
         because
Default handler: &latex;
Default handler: &textrsquo;
        s standard classes have already defined a
        <code>
          \section
        </code>
        . For the same reason it does not define a
        <code>
          section
        </code>
         counter, or the commands
        <code>
          \thesection
        </code>
         and
        <code>
          \l
Default handler: &arobase;
          section
        </code>
        .
      </para>
      <example endspaces=" ">
        <pre xml:space="preserve">
          \renewcommand\section
Default handler: &lbrace;
          % \
Default handler: &arobase;
          startsection
Default handler: &lbrace;
          section
Default handler: &rbrace;
          %
          <ref label="_005c_0040startsection_002fname">
            <xrefnodename>
              \
Default handler: &arobase;
              startsection/name
            </xrefnodename>
            <xrefinfoname>
              <var>
                name
              </var>
            </xrefinfoname>
            <xrefprinteddesc>
              <var>
                name
              </var>
            </xrefprinteddesc>
          </ref>
Default handler: &lbrace;
          1
Default handler: &rbrace;
          %
          <ref label="_005c_0040startsection_002flevel">
            <xrefnodename>
              \
Default handler: &arobase;
              startsection/level
            </xrefnodename>
            <xrefinfoname>
              <var>
                level
              </var>
            </xrefinfoname>
            <xrefprinteddesc>
              <var>
                level
              </var>
            </xrefprinteddesc>
          </ref>
Default handler: &lbrace;
          0pt
Default handler: &rbrace;
          %
          <ref label="_005c_0040startsection_002findent">
            <xrefnodename>
              \
Default handler: &arobase;
              startsection/indent
            </xrefnodename>
            <xrefinfoname>
              <var>
                indent
              </var>
            </xrefinfoname>
            <xrefprinteddesc>
              <var>
                indent
              </var>
            </xrefprinteddesc>
          </ref>
Default handler: &lbrace;
          -3.5ex plus -1ex minus -.2ex
Default handler: &rbrace;
          %
          <ref label="_005c_0040startsection_002fbeforeskip">
            <xrefnodename>
              \
Default handler: &arobase;
              startsection/beforeskip
            </xrefnodename>
            <xrefinfoname>
              <var>
                beforeskip
              </var>
            </xrefinfoname>
            <xrefprinteddesc>
              <var>
                beforeskip
              </var>
            </xrefprinteddesc>
          </ref>
Default handler: &lbrace;
          2.3ex plus.2ex
Default handler: &rbrace;
          %
          <ref label="_005c_0040startsection_002fafterskip">
            <xrefnodename>
              \
Default handler: &arobase;
              startsection/afterskip
            </xrefnodename>
            <xrefinfoname>
              <var>
                afterskip
              </var>
            </xrefinfoname>
            <xrefprinteddesc>
              <var>
                afterskip
              </var>
            </xrefprinteddesc>
          </ref>
Default handler: &lbrace;
          \centering\normalfont\Large\bfseries
Default handler: &rbrace;
          %
          <ref label="_005c_0040startsection_002fstyle">
            <xrefnodename>
              \
Default handler: &arobase;
              startsection/style
            </xrefnodename>
            <xrefinfoname>
              <var>
                style
              </var>
            </xrefinfoname>
            <xrefprinteddesc>
              <var>
                style
              </var>
            </xrefprinteddesc>
          </ref>
Default handler: &rbrace;
        </pre>
      </example>
      <para>
        This will put
        <code>
          subsection
        </code>
         titles in small caps type, inline with the paragraph.
      </para>
      <example endspaces=" ">
        <pre xml:space="preserve">
          \renewcommand\subsection
Default handler: &lbrace;
          % \
Default handler: &arobase;
          startsection
Default handler: &lbrace;
          subsection
Default handler: &rbrace;
          %
          <ref label="_005c_0040startsection_002fname">
            <xrefnodename>
              \
Default handler: &arobase;
              startsection/name
            </xrefnodename>
            <xrefinfoname>
              <var>
                name
              </var>
            </xrefinfoname>
            <xrefprinteddesc>
              <var>
                name
              </var>
            </xrefprinteddesc>
          </ref>
Default handler: &lbrace;
          2
Default handler: &rbrace;
          %
          <ref label="_005c_0040startsection_002flevel">
            <xrefnodename>
              \
Default handler: &arobase;
              startsection/level
            </xrefnodename>
            <xrefinfoname>
              <var>
                level
              </var>
            </xrefinfoname>
            <xrefprinteddesc>
              <var>
                level
              </var>
            </xrefprinteddesc>
          </ref>
Default handler: &lbrace;
          0em
Default handler: &rbrace;
          %
          <ref label="_005c_0040startsection_002findent">
            <xrefnodename>
              \
Default handler: &arobase;
              startsection/indent
            </xrefnodename>
            <xrefinfoname>
              <var>
                indent
              </var>
            </xrefinfoname>
            <xrefprinteddesc>
              <var>
                indent
              </var>
            </xrefprinteddesc>
          </ref>
Default handler: &lbrace;
          -1ex plus 0.1ex minus -0.05ex
Default handler: &rbrace;
          %
          <ref label="_005c_0040startsection_002fbeforeskip">
            <xrefnodename>
              \
Default handler: &arobase;
              startsection/beforeskip
            </xrefnodename>
            <xrefinfoname>
              <var>
                beforeskip
              </var>
            </xrefinfoname>
            <xrefprinteddesc>
              <var>
                beforeskip
              </var>
            </xrefprinteddesc>
          </ref>
Default handler: &lbrace;
          -1em plus 0.2em
Default handler: &rbrace;
          %
          <ref label="_005c_0040startsection_002fafterskip">
            <xrefnodename>
              \
Default handler: &arobase;
              startsection/afterskip
            </xrefnodename>
            <xrefinfoname>
              <var>
                afterskip
              </var>
            </xrefinfoname>
            <xrefprinteddesc>
              <var>
                afterskip
              </var>
            </xrefprinteddesc>
          </ref>
Default handler: &lbrace;
          \scshape
Default handler: &rbrace;
          %
          <ref label="_005c_0040startsection_002fstyle">
            <xrefnodename>
              \
Default handler: &arobase;
              startsection/style
            </xrefnodename>
            <xrefinfoname>
              <var>
                style
              </var>
            </xrefinfoname>
            <xrefprinteddesc>
              <var>
                style
              </var>
            </xrefprinteddesc>
          </ref>
Default handler: &rbrace;
        </pre>
      </example>
      <para>
        The prior examples redefined existing sectional unit title commands. This defines a new one, illustrating the needed counter and macros to display that counter.
      </para>
Default handler: <!-- c From https://groups.google.com/forum/#!searchin/comp.text.tex/startsection%7Csort:relevance/comp.text.tex/sB-nTS-oL08/ZZeKYdG0llMJ -->
      <example endspaces=" ">
        <pre xml:space="preserve">
          \setcounter
Default handler: &lbrace;
          secnumdepth
Default handler: &rbrace;
Default handler: &lbrace;
          6
Default handler: &rbrace;
          % show counters this far down \newcounter
Default handler: &lbrace;
          subsubparagraph
Default handler: &rbrace;
          [subparagraph]% counter for numbering \renewcommand
Default handler: &lbrace;
          \thesubsubparagraph
Default handler: &rbrace;
          % how to display
Default handler: &lbrace;
          \thesubparagraph.\
Default handler: &arobase;
          arabic\c
Default handler: &arobase;
          subsubparagraph
Default handler: &rbrace;
          % numbering \newcommand
Default handler: &lbrace;
          \subsubparagraph
Default handler: &rbrace;
Default handler: &lbrace;
          \
Default handler: &arobase;
          startsection
Default handler: &lbrace;
          subsubparagraph
Default handler: &rbrace;
          %
Default handler: &lbrace;
          6
Default handler: &rbrace;
          %
Default handler: &lbrace;
          0em
Default handler: &rbrace;
          %
Default handler: &lbrace;
          \baselineskip
Default handler: &rbrace;
          %
Default handler: &lbrace;
          0.5\baselineskip
Default handler: &rbrace;
          %
Default handler: &lbrace;
          \normalfont\normalsize
Default handler: &rbrace;
Default handler: &rbrace;
           \newcommand*\l
Default handler: &arobase;
          subsubparagraph
Default handler: &lbrace;
          \
Default handler: &arobase;
          dottedtocline
Default handler: &lbrace;
          6
Default handler: &rbrace;
Default handler: &lbrace;
          10em
Default handler: &rbrace;
Default handler: &lbrace;
          5em
Default handler: &rbrace;
Default handler: &rbrace;
          % for toc \newcommand
Default handler: &lbrace;
          \subsubparagraphmark
Default handler: &rbrace;
          [1]
Default handler: &lbrace;
Default handler: &rbrace;
          % for page headers
        </pre>
      </example>
    </section>
  </chapter>
  <node name="Cross-references" spaces=" ">
    <nodename>
      Cross references
    </nodename>
    <nodenext automatic="on">
      Environments
    </nodenext>
    <nodeprev automatic="on">
      Sectioning
    </nodeprev>
    <nodeup automatic="on">
      Top
    </nodeup>
  </node>
  <chapter spaces=" ">
    <sectiontitle>
      Cross references
    </sectiontitle>
    <cindex index="cp" spaces=" ">
      <indexterm index="cp" number="284">
        cross references
      </indexterm>
    </cindex>
    <cindex index="cp" spaces=" ">
      <indexterm index="cp" number="285">
        label
      </indexterm>
    </cindex>
    <para>
      We often want something like
      <samp>
        See Theorem~31
      </samp>
      . But by-hand typing the 31 is poor practice. Instead you should write a
      <dfn>
        label
      </dfn>
       such as
      <code>
        \label
Default handler: &lbrace;
        eq:GreensThm
Default handler: &rbrace;
      </code>
       and then
      <dfn>
        reference
      </dfn>
       it, as with
      <code>
        See equation~\ref
Default handler: &lbrace;
        eq:GreensThm
Default handler: &rbrace;
      </code>
      .
Default handler: &latex;
       will automatically work out the number, put it into the output, and will change that number later if needed.
    </para>
    <example endspaces=" ">
      <pre xml:space="preserve">
        We will see this with Theorem~\ref
Default handler: &lbrace;
        th:GreensThm
Default handler: &rbrace;
        . % forward reference ... \begin
Default handler: &lbrace;
        theorem
Default handler: &rbrace;
         \label
Default handler: &lbrace;
        th:GreensThm
Default handler: &rbrace;
         ... \end
Default handler: &lbrace;
        theorem
Default handler: &rbrace;
         ... See Theorem~\ref
Default handler: &lbrace;
        th:GreensThm
Default handler: &rbrace;
         on page~\pageref
Default handler: &lbrace;
        th:GreensThm
Default handler: &rbrace;
        .
      </pre>
    </example>
    <paraDefault handler: &latex;
>
       tracks cross reference information in a file having the extension
      <file>
        .aux
      </file>
       and with the same base name as the file containing the
      <code>
        \label
      </code>
      . So if
      <code>
        \label
      </code>
       is in
      <file>
        calculus.tex
      </file>
       then the information is in
      <file>
        calculus.aux
      </file>
      .
Default handler: &latex;
       puts the information in that file every time it runs across a
      <code>
        \label
      </code>
      .
    </para>
    <cindex index="cp" spaces=" ">
      <indexterm index="cp" number="286">
        forward reference
      </indexterm>
    </cindex>
    <cindex index="cp" spaces=" ">
      <indexterm index="cp" number="287">
        reference, forward
      </indexterm>
    </cindex>
    <para>
      The behavior described in the prior paragraph results in a quirk that happens when your document has a
      <dfn>
        forward reference
      </dfn>
      , a
      <code>
        \ref
      </code>
       that appears before the associated
      <code>
        \label
      </code>
      . If this is the first time that you are compiling the document then you will get
      <samp>
        LaTeX Warning: Label(s) may have changed. Rerun to get cross references right
      </samp>
       and in the output the forward reference will appear as two question marks
Default handler: &nbsp;
      <samp>
        ??
      </samp>
      , in boldface. A similar thing happens if you change some things so the references changes; you get the same warning and the output contains the old reference information. In both cases, resolve this by compiling the document a second time.
    </para>
    <cindex index="cp" spaces=" ">
      <indexterm index="cp" number="288">
        <r>
          package
        </r>
        ,
        <code>
          cleveref
        </code>
      </indexterm>
    </cindex>
    <cindex index="cp" spaces=" ">
      <indexterm index="cp" number="289">
        <code>
          cleveref
        </code>
        <r>
          package
        </r>
      </indexterm>
    </cindex>
    <para>
      The
      <code>
        cleveref
      </code>
       package enhances
Default handler: &latex;
Default handler: &textrsquo;
      s cross referencing features. You can arrange that if you enter
      <code>
        \begin
Default handler: &lbrace;
        thm
Default handler: &rbrace;
        \label
Default handler: &lbrace;
        th:Nerode
Default handler: &rbrace;
        ...\end
Default handler: &lbrace;
        thm
Default handler: &rbrace;
      </code>
       then
      <code>
        \cref
Default handler: &lbrace;
        th:Nerode
Default handler: &rbrace;
      </code>
       will output
      <samp>
        Theorem 3.21
      </samp>
      , without you having to enter the
Default handler: &textldquo;
      Theorem.
Default handler: &textrdquo;
    </para>
    <menu endspaces=" ">
      <menuentry>
        <menuleadingtext>
          *
        </menuleadingtext>
        <menunode>
          \label
        </menunode>
        <menuseparator>
          ::
        </menuseparator>
        <menudescription>
          <pre xml:space="preserve">
            Assign a symbolic name to a piece of text.
          </pre>
        </menudescription>
      </menuentry>
      <menuentry>
        <menuleadingtext>
          *
        </menuleadingtext>
        <menunode>
          \pageref
        </menunode>
        <menuseparator>
          ::
        </menuseparator>
        <menudescription>
          <pre xml:space="preserve">
            Refer to a page number.
          </pre>
        </menudescription>
      </menuentry>
      <menuentry>
        <menuleadingtext>
          *
        </menuleadingtext>
        <menunode>
          \ref
        </menunode>
        <menuseparator>
          ::
        </menuseparator>
        <menudescription>
          <pre xml:space="preserve">
            Refer to a section, figure or similar.
          </pre>
        </menudescription>
      </menuentry>
      <menuentry>
        <menuleadingtext>
          *
        </menuleadingtext>
        <menunode>
          xr package
        </menunode>
        <menuseparator>
          ::
        </menuseparator>
        <menudescription>
          <pre xml:space="preserve">
            References from another document.
          </pre>
        </menudescription>
      </menuentry>
    </menu>
    <node name="_005clabel" spaces=" ">
      <nodename>
        \label
      </nodename>
      <nodenext automatic="on">
        \pageref
      </nodenext>
      <nodeup automatic="on">
        Cross references
      </nodeup>
    </node>
    <section spaces=" ">
      <sectiontitle>
        <code>
          \label
        </code>
      </sectiontitle>
      <findex index="fn" spaces=" ">
        <indexterm index="fn" number="266" mergedindex="cp">
          \label
        </indexterm>
      </findex>
      <para>
        Synopsis:
      </para>
      <example endspaces=" ">
        <pre xml:space="preserve">
          \label
Default handler: &lbrace;
          <var>
            key
          </var>
Default handler: &rbrace;
        </pre>
      </example>
      <para>
        Assign a reference number to
        <var>
          key
        </var>
        . In ordinary text
        <code>
          \label
Default handler: &lbrace;
          <var>
            key
          </var>
Default handler: &rbrace;
        </code>
         assigns to
        <var>
          key
        </var>
         the number of the current sectional unit. Inside an environment with numbering, such as a
        <code>
          table
        </code>
         or
        <code>
          theorem
        </code>
         environment,
        <code>
          \label
Default handler: &lbrace;
          <var>
            key
          </var>
Default handler: &rbrace;
        </code>
         assigns to
        <var>
          key
        </var>
         the number of that environment. Retrieve the assigned number with the
        <code>
          \ref
Default handler: &lbrace;
          <var>
            key
          </var>
Default handler: &rbrace;
        </code>
         command (
        <pxref label="_005cref">
          <xrefnodename>
            \ref
          </xrefnodename>
        </pxref>
        ).
      </para>
      <para>
        A key name can consist of any sequence of letters, digits, or common punctuation characters. Upper and lowercase letters are distinguished, as usual.
      </para>
      <para>
        A common convention is to use labels consisting of a prefix and a suffix separated by a colon or period. Thus,
        <code>
          \label
Default handler: &lbrace;
          fig:Post
Default handler: &rbrace;
        </code>
         is a label for a figure with a portrait of Emil Post. This helps to avoid accidentally creating two labels with the same name, and makes your source more readable. Some commonly-used prefixes:
      </para>
      <table commandarg="code" spaces=" " endspaces=" ">
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                ch
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <para>
              for chapters
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                sec
              </itemformat>
            </item>
            <itemx spaces=" ">
              <itemformat command="code">
                subsec
              </itemformat>
            </itemx>
          </tableterm>
          <tableitem>
            <para>
              for lower-level sectioning commands
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                fig
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <para>
              for figures
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                tab
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <para>
              for tables
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                eq
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <para>
              for equations
            </para>
          </tableitem>
        </tableentry>
      </table>
      <para>
        In the auxiliary file the reference information is kept as the text of a command of the form
        <code>
          \newlabel
Default handler: &lbrace;
          <var>
            label
          </var>
Default handler: &rbrace;
Default handler: &lbrace;
Default handler: &lbrace;
          <var>
            currentlabel
          </var>
Default handler: &rbrace;
Default handler: &lbrace;
          <var>
            pagenumber
          </var>
Default handler: &rbrace;
Default handler: &rbrace;
        </code>
        . Here
        <var>
          currentlabel
        </var>
         is the current value of the macro
        <code>
          \
Default handler: &arobase;
          currentlabel
        </code>
         that is usually updated whenever you call
        <code>
          \refstepcounter
Default handler: &lbrace;
          <var>
            counter
          </var>
Default handler: &rbrace;
        </code>
        .
      </para>
      <para>
        Below, the key
        <code>
          sec:test
        </code>
         will get the number of the current section and the key
        <code>
          fig:test
        </code>
         will get the number of the figure. (Incidentally, put labels after captions in figures and tables.)
      </para>
      <example endspaces=" ">
        <pre xml:space="preserve">
          \section
Default handler: &lbrace;
          section name
Default handler: &rbrace;
           \label
Default handler: &lbrace;
          sec:test
Default handler: &rbrace;
           This is Section~\ref
Default handler: &lbrace;
          sec:test
Default handler: &rbrace;
          . \begin
Default handler: &lbrace;
          figure
Default handler: &rbrace;
           ... \caption
Default handler: &lbrace;
          caption text
Default handler: &rbrace;
           \label
Default handler: &lbrace;
          fig:test
Default handler: &rbrace;
           \end
Default handler: &lbrace;
          figure
Default handler: &rbrace;
           See Figure~\ref
Default handler: &lbrace;
          fig:test
Default handler: &rbrace;
          .
        </pre>
      </example>
    </section>
    <node name="_005cpageref" spaces=" ">
      <nodename>
        \pageref
      </nodename>
      <nodenext automatic="on">
        \ref
      </nodenext>
      <nodeprev automatic="on">
        \label
      </nodeprev>
      <nodeup automatic="on">
        Cross references
      </nodeup>
    </node>
    <section spaces=" ">
      <sectiontitle>
        <code>
          \pageref
        </code>
      </sectiontitle>
      <findex index="fn" spaces=" ">
        <indexterm index="fn" number="267" mergedindex="cp">
          \pageref
        </indexterm>
      </findex>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="290">
          cross referencing with page number
        </indexterm>
      </cindex>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="291">
          page number, cross referencing
        </indexterm>
      </cindex>
      <para>
        Synopsis:
      </para>
      <example endspaces=" ">
        <pre xml:space="preserve">
          \pageref
Default handler: &lbrace;
          <var>
            key
          </var>
Default handler: &rbrace;
        </pre>
      </example>
      <para>
        Produce the page number of the place in the text where the corresponding
        <code>
          \label
        </code>
Default handler: &lbrace;
        <var>
          key
        </var>
Default handler: &rbrace;
         command appears.
      </para>
      <para>
        If there is no
        <code>
          \label
Default handler: &lbrace;
          <var>
            key
          </var>
Default handler: &rbrace;
        </code>
         then you get something like
        <samp>
          LaTeX Warning: Reference `th:GrensThm' on page 1 undefined on input line 11.
        </samp>
      </para>
      <para>
        Below, the
        <code>
          \label
Default handler: &lbrace;
          eq:main
Default handler: &rbrace;
        </code>
         is used both for the formula number and for the page number. (Note that the two references are forward references so this document would need to be compiled twice to resolve those.)
      </para>
      <example endspaces=" ">
        <pre xml:space="preserve">
          The main result is formula~\ref
Default handler: &lbrace;
          eq:main
Default handler: &rbrace;
           on page~\pageref
Default handler: &lbrace;
          eq:main
Default handler: &rbrace;
          . ... \begin
Default handler: &lbrace;
          equation
Default handler: &rbrace;
           \label
Default handler: &lbrace;
          eq:main
Default handler: &rbrace;
           \mathbf
Default handler: &lbrace;
          P
Default handler: &rbrace;
          =\mathbf
Default handler: &lbrace;
          NP
Default handler: &rbrace;
           \end
Default handler: &lbrace;
          equation
Default handler: &rbrace;
        </pre>
      </example>
    </section>
    <node name="_005cref" spaces=" ">
      <nodename>
        \ref
      </nodename>
      <nodenext automatic="on">
        xr package
      </nodenext>
      <nodeprev automatic="on">
        \pageref
      </nodeprev>
      <nodeup automatic="on">
        Cross references
      </nodeup>
    </node>
    <section spaces=" ">
      <sectiontitle>
        <code>
          \ref
        </code>
      </sectiontitle>
      <findex index="fn" spaces=" ">
        <indexterm index="fn" number="268" mergedindex="cp">
          \ref
        </indexterm>
      </findex>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="292">
          cross referencing, symbolic
        </indexterm>
      </cindex>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="293">
          section number, cross referencing
        </indexterm>
      </cindex>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="294">
          equation number, cross referencing
        </indexterm>
      </cindex>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="295">
          figure number, cross referencing
        </indexterm>
      </cindex>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="296">
          footnote number, cross referencing
        </indexterm>
      </cindex>
      <para>
        Synopsis:
      </para>
      <example endspaces=" ">
        <pre xml:space="preserve">
          \ref
Default handler: &lbrace;
          <var>
            key
          </var>
Default handler: &rbrace;
        </pre>
      </example>
      <para>
        Produces the number of the sectional unit, equation, footnote, figure,
Default handler: &dots;
        , of the corresponding
        <code>
          \label
        </code>
         command (
        <pxref label="_005clabel">
          <xrefnodename>
            \label
          </xrefnodename>
        </pxref>
        ). It does not produce any text, such as the word
Default handler: &textlsquo;
        Section
Default handler: &textrsquo;
         or
Default handler: &textlsquo;
        Figure
Default handler: &textrsquo;
        , just the bare number itself.
      </para>
      <para>
        If there is no
        <code>
          \label
Default handler: &lbrace;
          <var>
            key
          </var>
Default handler: &rbrace;
        </code>
         then you get something like
        <samp>
          LaTeX Warning: Reference `th:GrensThm' on page 1 undefined on input line 11.
        </samp>
      </para>
      <para>
        In this example the
        <code>
          \ref
Default handler: &lbrace;
          popular
Default handler: &rbrace;
        </code>
         produces
        <samp>
          2
        </samp>
        . Note that it is a forward reference since it comes before
        <code>
          \label
Default handler: &lbrace;
          popular
Default handler: &rbrace;
        </code>
         so this document would have to be compiled twice.
      </para>
      <example endspaces=" ">
        <pre xml:space="preserve">
          The most widely-used format is item number~\ref
Default handler: &lbrace;
          popular
Default handler: &rbrace;
          . \begin
Default handler: &lbrace;
          enumerate
Default handler: &rbrace;
           \item Plain \TeX \item \label
Default handler: &lbrace;
          popular
Default handler: &rbrace;
           \LaTeX \item Con\TeX t \end
Default handler: &lbrace;
          enumerate
Default handler: &rbrace;
        </pre>
      </example>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="297">
          <r>
            package
          </r>
          ,
          <code>
            cleveref
          </code>
        </indexterm>
      </cindex>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="298">
          <code>
            cleveref
          </code>
          <r>
            package
          </r>
        </indexterm>
      </cindex>
      <para>
        The
        <code>
          cleveref
        </code>
         package includes text such as
        <samp>
          Theorem
        </samp>
         in the reference. See the documentation on CTAN.
      </para>
    </section>
    <node name="xr-package" spaces=" ">
      <nodename>
        xr package
      </nodename>
      <nodeprev automatic="on">
        \ref
      </nodeprev>
      <nodeup automatic="on">
        Cross references
      </nodeup>
    </node>
    <section spaces=" ">
      <sectiontitle>
        <code>
          xr
        </code>
         package
      </sectiontitle>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="299">
          <r>
            package
          </r>
          ,
          <code>
            xr
          </code>
        </indexterm>
      </cindex>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="300">
          <code>
            xr
          </code>
          <r>
            package
          </r>
        </indexterm>
      </cindex>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="301">
          <r>
            package
          </r>
          ,
          <code>
            xr-hyper
          </code>
        </indexterm>
      </cindex>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="302">
          <code>
            xr-hyper
          </code>
          <r>
            package
          </r>
        </indexterm>
      </cindex>
      <findex index="fn" spaces=" ">
        <indexterm index="fn" number="269" mergedindex="cp">
          \externaldocument
        </indexterm>
      </findex>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="303">
          cross referencing, across documents
        </indexterm>
      </cindex>
      <para>
        Synopsis:
      </para>
      <example endspaces=" ">
        <pre xml:space="preserve">
          \usepackage
Default handler: &lbrace;
          xr
Default handler: &rbrace;
           \externaldocument
Default handler: &lbrace;
          <var>
            document-basename
          </var>
Default handler: &rbrace;
        </pre>
      </example>
      <noindent/>
      <para>
        or
      </para>
      <example endspaces=" ">
        <pre xml:space="preserve">
          \usepackage
Default handler: &lbrace;
          xr
Default handler: &rbrace;
           \externaldocument[
          <var>
            reference-prefix
          </var>
          ]
Default handler: &lbrace;
          <var>
            document-basename
          </var>
Default handler: &rbrace;
        </pre>
      </example>
      <para>
        Make cross references to the external document
        <file>
          <var>
            document-basename
          </var>
          .tex
        </file>
        .
      </para>
      <para>
        Here is an example. If
        <file>
          lectures.tex
        </file>
         has this in the preamble
      </para>
      <example endspaces=" ">
        <pre xml:space="preserve">
          \usepackage
Default handler: &lbrace;
          xr
Default handler: &rbrace;
           \externaldocument
Default handler: &lbrace;
          exercises
Default handler: &rbrace;
           \externaldocument[H-]
Default handler: &lbrace;
          hints
Default handler: &rbrace;
           \externaldocument
Default handler: &lbrace;
          answers
Default handler: &rbrace;
        </pre>
      </example>
      <noindent/>
      <para>
        then it can use cross reference labels from the other three documents. Suppose that
        <file>
          exercises.tex
        </file>
         has an enumerated list containing this,
      </para>
      <example endspaces=" ">
        <pre xml:space="preserve">
          \item \label
Default handler: &lbrace;
          exer:EulersThm
Default handler: &rbrace;
           What if every vertex has odd degree?
        </pre>
      </example>
      <noindent/>
      <para>
        and
        <file>
          hints.tex
        </file>
         has an enumerated list with this,
      </para>
      <example endspaces=" ">
        <pre xml:space="preserve">
          \item \label
Default handler: &lbrace;
          exer:EulersThm
Default handler: &rbrace;
           Distinguish the case of two vertices.
        </pre>
      </example>
      <noindent/>
      <para>
        and
        <file>
          answers.tex
        </file>
         has an enumerated list with this,
      </para>
      <example endspaces=" ">
        <pre xml:space="preserve">
          \item \label
Default handler: &lbrace;
          ans:EulersThm
Default handler: &rbrace;
           There is no Euler path, except if there are exactly two vertices.
        </pre>
      </example>
      <para>
        After compiling the exercises, hints, and answers documents, entering this in the body of
        <file>
          lectures.tex
        </file>
         will result in the lectures getting the reference numbers used in the other documents.
      </para>
      <example endspaces=" ">
        <pre xml:space="preserve">
          See Exercise~\ref
Default handler: &lbrace;
          exer:EulersThm
Default handler: &rbrace;
          , with Hint~\ref
Default handler: &lbrace;
          H-exer:EulersThm
Default handler: &rbrace;
          . The solution is Answer~\ref
Default handler: &lbrace;
          ans:EulersThm
Default handler: &rbrace;
          .
        </pre>
      </example>
      <para>
        The prefix
        <code>
          H-
        </code>
         for the reference from the hints file is needed because the label in the hints file is the same as the label in the exercises file. Without that prefix, both references would get the number from the later file.
      </para>
      <para>
        Note: if the document uses the
        <code>
          hyperref
        </code>
         package then in place of
        <code>
          xr
        </code>
        , put
        <code>
          \usepackage
Default handler: &lbrace;
          xr-hyper
Default handler: &rbrace;
        </code>
         before the
        <code>
          \usepackage
Default handler: &lbrace;
          hyperref
Default handler: &rbrace;
        </code>
        . Also, if any of the multiple documents uses
        <code>
          hyperref
        </code>
         then they all must use it.
      </para>
    </section>
  </chapter>
  <node name="Environments" spaces=" ">
    <nodename>
      Environments
    </nodename>
    <nodenext automatic="on">
      Line breaking
    </nodenext>
    <nodeprev automatic="on">
      Cross references
    </nodeprev>
    <nodeup automatic="on">
      Top
    </nodeup>
  </node>
  <chapter spaces=" ">
    <sectiontitle>
      Environments
    </sectiontitle>
    <cindex index="cp" spaces=" ">
      <indexterm index="cp" number="304">
        environments
      </indexterm>
    </cindex>
    <findex index="fn" spaces=" ">
      <indexterm index="fn" number="270" mergedindex="cp">
        \begin
      </indexterm>
    </findex>
    <findex index="fn" spaces=" ">
      <indexterm index="fn" number="271" mergedindex="cp">
        \end
      </indexterm>
    </findex>
    <anchor name="Environment">
      Environment
    </anchor>
Default handler: <!-- c old name -->
    <paraDefault handler: &latex;
>
       provides many environments for delimiting certain behavior. An environment begins with
      <code>
        \begin
      </code>
       and ends with
      <code>
        \end
      </code>
      , like this:
    </para>
    <example endspaces=" ">
      <pre xml:space="preserve">
        \begin
Default handler: &lbrace;
        <var>
          environment-name
        </var>
Default handler: &rbrace;
         ... \end
Default handler: &lbrace;
        <var>
          environment-name
        </var>
Default handler: &rbrace;
      </pre>
    </example>
    <para>
      The
      <var>
        environment-name
      </var>
       at the beginning must exactly match that at the end. For instance, the input
      <code>
        \begin
Default handler: &lbrace;
        table*
Default handler: &rbrace;
        ...\end
Default handler: &lbrace;
        table
Default handler: &rbrace;
      </code>
       will cause an error like:
      <samp>
        ! LaTeX Error: \begin
Default handler: &lbrace;
        table*
Default handler: &rbrace;
         on input line 5 ended by \end
Default handler: &lbrace;
        table
Default handler: &rbrace;
        .
      </samp>
    </para>
    <cindex index="cp" spaces=" ">
      <indexterm index="cp" number="305">
        group, and environments
      </indexterm>
    </cindex>
    <para>
      Environments are executed within a group.
    </para>
    <menu endspaces=" ">
      <menuentry>
        <menuleadingtext>
          *
        </menuleadingtext>
        <menunode>
          abstract
        </menunode>
        <menuseparator>
          ::
        </menuseparator>
        <menudescription>
          <pre xml:space="preserve">
            Produce an abstract.
          </pre>
        </menudescription>
      </menuentry>
      <menuentry>
        <menuleadingtext>
          *
        </menuleadingtext>
        <menunode>
          array
        </menunode>
        <menuseparator>
          ::
        </menuseparator>
        <menudescription>
          <pre xml:space="preserve">
            Math arrays.
          </pre>
        </menudescription>
      </menuentry>
      <menuentry>
        <menuleadingtext>
          *
        </menuleadingtext>
        <menunode>
          center
        </menunode>
        <menuseparator>
          ::
        </menuseparator>
        <menudescription>
          <pre xml:space="preserve">
            Centered lines.
          </pre>
        </menudescription>
      </menuentry>
      <menuentry>
        <menuleadingtext>
          *
        </menuleadingtext>
        <menunode>
          description
        </menunode>
        <menuseparator>
          ::
        </menuseparator>
        <menudescription>
          <pre xml:space="preserve">
            Labelled lists.
          </pre>
        </menudescription>
      </menuentry>
      <menuentry>
        <menuleadingtext>
          *
        </menuleadingtext>
        <menunode>
          displaymath
        </menunode>
        <menuseparator>
          ::
        </menuseparator>
        <menudescription>
          <pre xml:space="preserve">
            Formulas that appear on their own line.
          </pre>
        </menudescription>
      </menuentry>
      <menuentry>
        <menuleadingtext>
          *
        </menuleadingtext>
        <menunode>
          document
        </menunode>
        <menuseparator>
          ::
        </menuseparator>
        <menudescription>
          <pre xml:space="preserve">
            Enclose the whole document.
          </pre>
        </menudescription>
      </menuentry>
      <menuentry>
        <menuleadingtext>
          *
        </menuleadingtext>
        <menunode>
          enumerate
        </menunode>
        <menuseparator>
          ::
        </menuseparator>
        <menudescription>
          <pre xml:space="preserve">
            Numbered lists.
          </pre>
        </menudescription>
      </menuentry>
      <menuentry>
        <menuleadingtext>
          *
        </menuleadingtext>
        <menunode>
          eqnarray
        </menunode>
        <menuseparator>
          ::
        </menuseparator>
        <menudescription>
          <pre xml:space="preserve">
            Sequences of aligned equations.
          </pre>
        </menudescription>
      </menuentry>
      <menuentry>
        <menuleadingtext>
          *
        </menuleadingtext>
        <menunode>
          equation
        </menunode>
        <menuseparator>
          ::
        </menuseparator>
        <menudescription>
          <pre xml:space="preserve">
            Displayed equation.
          </pre>
        </menudescription>
      </menuentry>
      <menuentry>
        <menuleadingtext>
          *
        </menuleadingtext>
        <menunode>
          figure
        </menunode>
        <menuseparator>
          ::
        </menuseparator>
        <menudescription>
          <pre xml:space="preserve">
            Floating figures.
          </pre>
        </menudescription>
      </menuentry>
      <menuentry>
        <menuleadingtext>
          *
        </menuleadingtext>
        <menunode>
          filecontents
        </menunode>
        <menuseparator>
          ::
        </menuseparator>
        <menudescription>
          <pre xml:space="preserve">
            Writing multiple files from the source.
          </pre>
        </menudescription>
      </menuentry>
      <menuentry>
        <menuleadingtext>
          *
        </menuleadingtext>
        <menunode>
          flushleft
        </menunode>
        <menuseparator>
          ::
        </menuseparator>
        <menudescription>
          <pre xml:space="preserve">
            Flushed left lines.
          </pre>
        </menudescription>
      </menuentry>
      <menuentry>
        <menuleadingtext>
          *
        </menuleadingtext>
        <menunode>
          flushright
        </menunode>
        <menuseparator>
          ::
        </menuseparator>
        <menudescription>
          <pre xml:space="preserve">
            Flushed right lines.
          </pre>
        </menudescription>
      </menuentry>
      <menuentry>
        <menuleadingtext>
          *
        </menuleadingtext>
        <menunode>
          itemize
        </menunode>
        <menuseparator>
          ::
        </menuseparator>
        <menudescription>
          <pre xml:space="preserve">
            Bulleted lists.
          </pre>
        </menudescription>
      </menuentry>
      <menuentry>
        <menuleadingtext>
          *
        </menuleadingtext>
        <menunode>
          letter
        </menunode>
        <menuseparator>
          ::
        </menuseparator>
        <menudescription>
          <pre xml:space="preserve">
            Letters.
          </pre>
        </menudescription>
      </menuentry>
      <menuentry>
        <menuleadingtext>
          *
        </menuleadingtext>
        <menunode>
          list
        </menunode>
        <menuseparator>
          ::
        </menuseparator>
        <menudescription>
          <pre xml:space="preserve">
            Generic list environment.
          </pre>
        </menudescription>
      </menuentry>
      <menuentry>
        <menuleadingtext>
          *
        </menuleadingtext>
        <menunode>
          math
        </menunode>
        <menuseparator>
          ::
        </menuseparator>
        <menudescription>
          <pre xml:space="preserve">
            In-line math.
          </pre>
        </menudescription>
      </menuentry>
      <menuentry>
        <menuleadingtext>
          *
        </menuleadingtext>
        <menunode>
          minipage
        </menunode>
        <menuseparator>
          ::
        </menuseparator>
        <menudescription>
          <pre xml:space="preserve">
            Miniature page.
          </pre>
        </menudescription>
      </menuentry>
      <menuentry>
        <menuleadingtext>
          *
        </menuleadingtext>
        <menunode>
          picture
        </menunode>
        <menuseparator>
          ::
        </menuseparator>
        <menudescription>
          <pre xml:space="preserve">
            Picture with text, arrows, lines and circles.
          </pre>
        </menudescription>
      </menuentry>
      <menuentry>
        <menuleadingtext>
          *
        </menuleadingtext>
        <menunode>
          quotation
          &
           quote
        </menunode>
        <menuseparator>
          ::
        </menuseparator>
        <menudescription>
          <pre xml:space="preserve">
            Include a quotation.
          </pre>
        </menudescription>
      </menuentry>
      <menuentry>
        <menuleadingtext>
          *
        </menuleadingtext>
        <menunode>
          tabbing
        </menunode>
        <menuseparator>
          ::
        </menuseparator>
        <menudescription>
          <pre xml:space="preserve">
            Align text arbitrarily.
          </pre>
        </menudescription>
      </menuentry>
      <menuentry>
        <menuleadingtext>
          *
        </menuleadingtext>
        <menunode>
          table
        </menunode>
        <menuseparator>
          ::
        </menuseparator>
        <menudescription>
          <pre xml:space="preserve">
            Floating tables.
          </pre>
        </menudescription>
      </menuentry>
      <menuentry>
        <menuleadingtext>
          *
        </menuleadingtext>
        <menunode>
          tabular
        </menunode>
        <menuseparator>
          ::
        </menuseparator>
        <menudescription>
          <pre xml:space="preserve">
            Align text in columns.
          </pre>
        </menudescription>
      </menuentry>
      <menuentry>
        <menuleadingtext>
          *
        </menuleadingtext>
        <menunode>
          thebibliography
        </menunode>
        <menuseparator>
          ::
        </menuseparator>
        <menudescription>
          <pre xml:space="preserve">
            Bibliography or reference list.
          </pre>
        </menudescription>
      </menuentry>
      <menuentry>
        <menuleadingtext>
          *
        </menuleadingtext>
        <menunode>
          theorem
        </menunode>
        <menuseparator>
          ::
        </menuseparator>
        <menudescription>
          <pre xml:space="preserve">
            Theorems, lemmas, etc.
          </pre>
        </menudescription>
      </menuentry>
      <menuentry>
        <menuleadingtext>
          *
        </menuleadingtext>
        <menunode>
          titlepage
        </menunode>
        <menuseparator>
          ::
        </menuseparator>
        <menudescription>
          <pre xml:space="preserve">
            For hand crafted title pages.
          </pre>
        </menudescription>
      </menuentry>
      <menuentry>
        <menuleadingtext>
          *
        </menuleadingtext>
        <menunode>
          verbatim
        </menunode>
        <menuseparator>
          ::
        </menuseparator>
        <menudescription>
          <pre xml:space="preserve">
            Simulating typed input.
          </pre>
        </menudescription>
      </menuentry>
      <menuentry>
        <menuleadingtext>
          *
        </menuleadingtext>
        <menunode>
          verse
        </menunode>
        <menuseparator>
          ::
        </menuseparator>
        <menudescription>
          <pre xml:space="preserve">
            For poetry and other things.
          </pre>
        </menudescription>
      </menuentry>
    </menu>
    <node name="abstract" spaces=" ">
      <nodename>
        abstract
      </nodename>
      <nodenext automatic="on">
        array
      </nodenext>
      <nodeup automatic="on">
        Environments
      </nodeup>
    </node>
    <section spaces=" ">
      <sectiontitle>
        <code>
          abstract
        </code>
      </sectiontitle>
      <findex index="fn" spaces=" ">
        <indexterm index="fn" number="272" mergedindex="cp">
          <r>
            environment
          </r>
          ,
          <code>
            abstract
          </code>
        </indexterm>
      </findex>
      <findex index="fn" spaces=" ">
        <indexterm index="fn" number="273" mergedindex="cp">
          <code>
            abstract
          </code>
          <r>
            environment
          </r>
        </indexterm>
      </findex>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="306">
          abstracts
        </indexterm>
      </cindex>
      <para>
        Synopsis:
      </para>
      <example endspaces=" ">
        <pre xml:space="preserve">
          \begin
Default handler: &lbrace;
          abstract
Default handler: &rbrace;
           ... \end
Default handler: &lbrace;
          abstract
Default handler: &rbrace;
        </pre>
      </example>
      <para>
        Produce an abstract, possibly of multiple paragraphs. This environment is only defined in the
        <code>
          article
        </code>
         and
        <code>
          report
        </code>
         document classes (
        <pxref label="Document-classes">
          <xrefnodename>
            Document classes
          </xrefnodename>
        </pxref>
        ).
      </para>
      <para>
        Using the example below in the
        <code>
          article
        </code>
         class produces a displayed paragraph. Document class option
        <code>
          titlepage
        </code>
         causes the abstract to be on a separate page (
        <pxref label="Document-class-options">
          <xrefnodename>
            Document class options
          </xrefnodename>
        </pxref>
        ); this is the default only in the
        <code>
          report
        </code>
         class.
      </para>
      <example endspaces=" ">
        <pre xml:space="preserve">
          \begin
Default handler: &lbrace;
          abstract
Default handler: &rbrace;
           We compare all known accounts of the proposal made by Porter Alexander to Robert E Lee at the Appomattox Court House that the army continue in a guerrilla war, which Lee refused. \end
Default handler: &lbrace;
          abstract
Default handler: &rbrace;
        </pre>
      </example>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="307">
          <r>
            package
          </r>
          ,
          <code>
            abstract
          </code>
        </indexterm>
      </cindex>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="308">
          <code>
            abstract
          </code>
          <r>
            package
          </r>
        </indexterm>
      </cindex>
      <para>
        The next example produces a one column abstract in a two column document (for a more flexible solution, use the package
        <code>
          abstract
        </code>
        ).
      </para>
Default handler: <!-- c Adopted from http://www.tex.ac.uk/FAQ-onecolabs.html -->
      <example endspaces=" ">
        <pre xml:space="preserve">
          \documentclass[twocolumn]
Default handler: &lbrace;
          article
Default handler: &rbrace;
           ... \begin
Default handler: &lbrace;
          document
Default handler: &rbrace;
           \title
Default handler: &lbrace;
          Babe Ruth as Cultural Progenitor: a Atavistic Approach
Default handler: &rbrace;
           \author
Default handler: &lbrace;
          Smith \\ Jones \\ Robinson\thanks
Default handler: &lbrace;
          Railroad tracking grant.
Default handler: &rbrace;
Default handler: &rbrace;
           \twocolumn[ \begin
Default handler: &lbrace;
Default handler: &arobase;
          twocolumnfalse
Default handler: &rbrace;
           \maketitle \begin
Default handler: &lbrace;
          abstract
Default handler: &rbrace;
           Ruth was not just the Sultan of Swat, he was the entire swat team. \end
Default handler: &lbrace;
          abstract
Default handler: &rbrace;
           \end
Default handler: &lbrace;
Default handler: &arobase;
          twocolumnfalse
Default handler: &rbrace;
           ]
Default handler: &lbrace;
           % by-hand insert a footnote at page bottom \renewcommand
Default handler: &lbrace;
          \thefootnote
Default handler: &rbrace;
Default handler: &lbrace;
          \fnsymbol
Default handler: &lbrace;
          footnote
Default handler: &rbrace;
Default handler: &rbrace;
           \footnotetext[1]
Default handler: &lbrace;
          Thanks for all the fish.
Default handler: &rbrace;
Default handler: &rbrace;
        </pre>
      </example>
    </section>
    <node name="array" spaces=" ">
      <nodename>
        array
      </nodename>
      <nodenext automatic="on">
        center
      </nodenext>
      <nodeprev automatic="on">
        abstract
      </nodeprev>
      <nodeup automatic="on">
        Environments
      </nodeup>
    </node>
    <section spaces=" ">
      <sectiontitle>
        <code>
          array
        </code>
      </sectiontitle>
      <findex index="fn" spaces=" ">
        <indexterm index="fn" number="274" mergedindex="cp">
          <r>
            environment
          </r>
          ,
          <code>
            array
          </code>
        </indexterm>
      </findex>
      <findex index="fn" spaces=" ">
        <indexterm index="fn" number="275" mergedindex="cp">
          <code>
            array
          </code>
          <r>
            environment
          </r>
        </indexterm>
      </findex>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="309">
          arrays, math
        </indexterm>
      </cindex>
      <para>
        Synopsis:
      </para>
      <example endspaces=" ">
        <pre xml:space="preserve">
          \begin
Default handler: &lbrace;
          array
Default handler: &rbrace;
Default handler: &lbrace;
          <var>
            cols
          </var>
Default handler: &rbrace;
          <var>
            column 1 entry
          </var>
          &
          <var>
            column 2 entry
          </var>
           ...
          &
          <var>
            column n entry
          </var>
           \\ ... \end
Default handler: &lbrace;
          array
Default handler: &rbrace;
        </pre>
      </example>
      <noindent/>
      <para>
        or:
      </para>
      <example endspaces=" ">
        <pre xml:space="preserve">
          \begin
Default handler: &lbrace;
          array
Default handler: &rbrace;
          [
          <var>
            pos
          </var>
          ]
Default handler: &lbrace;
          <var>
            cols
          </var>
Default handler: &rbrace;
          <var>
            column 1 entry
          </var>
          &
          <var>
            column 2 entry
          </var>
           ...
          &
          <var>
            column n entry
          </var>
           \\ ... \end
Default handler: &lbrace;
          array
Default handler: &rbrace;
        </pre>
      </example>
      <para>
        Produce a mathematical array. This environment can only be used in math mode (
        <pxref label="Modes">
          <xrefnodename>
            Modes
          </xrefnodename>
        </pxref>
        ), and normally appears within a displayed mathematics environment such as
        <code>
          equation
        </code>
         (
        <pxref label="equation">
          <xrefnodename>
            equation
          </xrefnodename>
        </pxref>
        ). Inside of each row the column entries are separated by an ampersand, (
        <code>
          &
        </code>
        ). Rows are terminated with double-backslashes (
        <pxref label="_005c_005c">
          <xrefnodename>
            \\
          </xrefnodename>
        </pxref>
        ).
      </para>
      <para>
        This example shows a three by three array.
      </para>
      <example endspaces=" ">
        <pre xml:space="preserve">
          \begin
Default handler: &lbrace;
          equation*
Default handler: &rbrace;
           \chi(x) = \left| % vertical bar fence \begin
Default handler: &lbrace;
          array
Default handler: &rbrace;
Default handler: &lbrace;
          ccc
Default handler: &rbrace;
           x-a
          &
          -b
          &
          -c \\ -d
          &
          x-e
          &
          -f \\ -g
          &
          -h
          &
          x-i \end
Default handler: &lbrace;
          array
Default handler: &rbrace;
           \right| \end
Default handler: &lbrace;
          equation*
Default handler: &rbrace;
        </pre>
      </example>
      <para>
        The required argument
        <var>
          cols
        </var>
         describes the number of columns, their alignment, and the formatting of the intercolumn regions. For instance,
        <code>
          \begin
Default handler: &lbrace;
          array
Default handler: &rbrace;
Default handler: &lbrace;
          rcl
Default handler: &rbrace;
          ...\end
Default handler: &lbrace;
          array
Default handler: &rbrace;
        </code>
         gives three columns: the first flush right, the second centered, and the third flush left. See
        <ref label="tabular">
          <xrefnodename>
            tabular
          </xrefnodename>
        </ref>
         for the complete description of
        <var>
          cols
        </var>
         and of the other common features of the two environments, including the optional
        <var>
          pos
        </var>
         argument.
      </para>
      <para>
        There are two ways that
        <code>
          array
        </code>
         diverges from
        <code>
          tabular
        </code>
        . The first is that
        <code>
          array
        </code>
         entries are typeset in math mode, in textstyle (
        <pxref label="Math-styles">
          <xrefnodename>
            Math styles
          </xrefnodename>
        </pxref>
        ) except if the
        <var>
          cols
        </var>
         definition specifies the column with
        <code>
          p
Default handler: &lbrace;
          ...
Default handler: &rbrace;
        </code>
        , which causes the entry to be typeset in text mode. The second is that, instead of
        <code>
          tabular
        </code>
Default handler: &textrsquo;
        s parameter
        <code>
          \tabcolsep
        </code>
        ,
Default handler: &latex;
Default handler: &textrsquo;
        s intercolumn space in an
        <code>
          array
        </code>
         is governed by
        <findex index="fn" spaces=" ">
          <indexterm index="fn" number="276" mergedindex="cp">
            \arraycolsep
          </indexterm>
        </findex>
        <code>
          \arraycolsep
        </code>
        , which gives half the width between columns. The default for this is
        <samp>
          5pt
        </samp>
         so that between two columns comes 10
        <dmn>
          pt
        </dmn>
         of space.
      </para>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="310">
          <r>
            package
          </r>
          ,
          <code>
            amsmath
          </code>
        </indexterm>
      </cindex>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="311">
          <code>
            amsmath
          </code>
          <r>
            package
          </r>
        </indexterm>
      </cindex>
      <para>
        To obtain arrays with braces the standard is to use the
        <code>
          amsmath
        </code>
         package. It comes with environments
        <code>
          pmatrix
        </code>
         for an array surrounded by parentheses
Default handler: &nbsp;
        <code>
          (...)
        </code>
        ,
        <code>
          bmatrix
        </code>
         for an array surrounded by square brackets
Default handler: &nbsp;
        <code>
          [...]
        </code>
        ,
        <code>
          Bmatrix
        </code>
         for an array surrounded by curly braces
Default handler: &nbsp;
        <codeDefault handler: &lbrace;
>
          ...
Default handler: &rbrace;
        </code>
        ,
        <code>
          vmatrix
        </code>
         for an array surrounded by vertical bars
Default handler: &nbsp;
        <code>
          |...|
        </code>
        , and
        <code>
          Vmatrix
        </code>
         for an array surrounded by double vertical bars
Default handler: &nbsp;
        <code>
          ||...||
        </code>
        , along with a number of other array constructs.
      </para>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="312">
          <r>
            package
          </r>
          ,
          <code>
            amsmath
          </code>
        </indexterm>
      </cindex>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="313">
          <code>
            amsmath
          </code>
          <r>
            package
          </r>
        </indexterm>
      </cindex>
      <para>
        The next example uses the
        <code>
          amsmath
        </code>
         package.
      </para>
      <example endspaces=" ">
        <pre xml:space="preserve">
          \usepackage
Default handler: &lbrace;
          amsmath
Default handler: &rbrace;
           % in preamble \begin
Default handler: &lbrace;
          equation
Default handler: &rbrace;
           \begin
Default handler: &lbrace;
          vmatrix
Default handler: &rbrace;
Default handler: &lbrace;
          cc
Default handler: &rbrace;
           % array with vert lines a
          &
          b \\ c
          &
          d \end
Default handler: &lbrace;
          vmatrix
Default handler: &rbrace;
          =ad-bc \end
Default handler: &lbrace;
          equation
Default handler: &rbrace;
        </pre>
      </example>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="314">
          <r>
            package
          </r>
          ,
          <code>
            array
          </code>
        </indexterm>
      </cindex>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="315">
          <code>
            array
          </code>
          <r>
            package
          </r>
        </indexterm>
      </cindex>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="316">
          <r>
            package
          </r>
          ,
          <code>
            dcolumn
          </code>
        </indexterm>
      </cindex>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="317">
          <code>
            dcolumn
          </code>
          <r>
            package
          </r>
        </indexterm>
      </cindex>
      <para>
        There are many packages concerning arrays. The
        <code>
          array
        </code>
         package has many useful extensions, including more column types. The
        <code>
          dcolumn
        </code>
         package adds a column type to center on a decimal point. For both see the documentation on CTAN.
      </para>
    </section>
    <node name="center" spaces=" ">
      <nodename>
        center
      </nodename>
      <nodenext automatic="on">
        description
      </nodenext>
      <nodeprev automatic="on">
        array
      </nodeprev>
      <nodeup automatic="on">
        Environments
      </nodeup>
    </node>
    <section spaces=" ">
      <sectiontitle>
        <code>
          center
        </code>
      </sectiontitle>
      <findex index="fn" spaces=" ">
        <indexterm index="fn" number="277" mergedindex="cp">
          <r>
            environment
          </r>
          ,
          <code>
            center
          </code>
        </indexterm>
      </findex>
      <findex index="fn" spaces=" ">
        <indexterm index="fn" number="278" mergedindex="cp">
          <code>
            center
          </code>
          <r>
            environment
          </r>
        </indexterm>
      </findex>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="318">
          centering text, environment for
        </indexterm>
      </cindex>
      <para>
        Synopsis:
      </para>
      <example endspaces=" ">
        <pre xml:space="preserve">
          \begin
Default handler: &lbrace;
          center
Default handler: &rbrace;
          <var>
            line1
          </var>
           \\
          <var>
            line2
          </var>
           \\ ... \end
Default handler: &lbrace;
          center
Default handler: &rbrace;
        </pre>
      </example>
      <para>
        Create a new paragraph consisting of a sequence of lines that are centered within the left and right margins. Use double-backslash,
        <code>
          \\
        </code>
        , to get a line break (
        <pxref label="_005c_005c">
          <xrefnodename>
            \\
          </xrefnodename>
        </pxref>
        ).
        <findex index="fn" spaces=" ">
          <indexterm index="fn" number="279" mergedindex="cp">
            \\
            <r>
              (for
              <code>
                center
              </code>
              )
            </r>
          </indexterm>
        </findex>
         If some text is too long to fit on a line then
Default handler: &latex;
         will insert line breaks that avoid hyphenation and avoid stretching or shrinking any interword space.
      </para>
      <para>
        This environment inserts space above and below the text body. See
        <ref label="_005ccentering">
          <xrefnodename>
            \centering
          </xrefnodename>
        </ref>
         to avoid such space, for example inside a
        <code>
          figure
        </code>
         environment.
      </para>
      <para>
        This example produces three centered lines. There is extra vertical space between the last two lines.
      </para>
      <example endspaces=" ">
        <pre xml:space="preserve">
          \begin
Default handler: &lbrace;
          center
Default handler: &rbrace;
           A Thesis Submitted in Partial Fufillment \\ of the Requirements of \\[0.5ex] the School of Environmental Engineering \end
Default handler: &lbrace;
          center
Default handler: &rbrace;
        </pre>
      </example>
      <para>
        In this example, depending on the page
Default handler: &textrsquo;
        s line width,
Default handler: &latex;
         may choose a line break for the part before the double backslash. If so, it will center each of the two lines and if not it will center the single line. Then
Default handler: &latex;
         will break at the double backslash, and will center the ending.
      </para>
      <example endspaces=" ">
        <pre xml:space="preserve">
          \begin
Default handler: &lbrace;
          center
Default handler: &rbrace;
           My father considered that anyone who went to chapel and didn't drink alcohol was not to be tolerated.\\ I grew up in that belief. ---Richard Burton \end
Default handler: &lbrace;
          center
Default handler: &rbrace;
        </pre>
      </example>
      <para>
        A double backslash after the final line is optional. If present it doesn
Default handler: &textrsquo;
        t add any vertical space.
      </para>
      <para>
        In a two-column document the text is centered in a column, not in the entire page.
      </para>
      <menu endspaces=" ">
        <menuentry>
          <menuleadingtext>
            *
          </menuleadingtext>
          <menunode>
            \centering
          </menunode>
          <menuseparator>
            ::
          </menuseparator>
          <menudescription>
            <pre xml:space="preserve">
              Declaration form of the
              <code>
                center
              </code>
               environment.
            </pre>
          </menudescription>
        </menuentry>
      </menu>
      <node name="_005ccentering" spaces=" ">
        <nodename>
          \centering
        </nodename>
        <nodeup automatic="on">
          center
        </nodeup>
      </node>
      <subsection spaces=" ">
        <sectiontitle>
          <code>
            \centering
          </code>
        </sectiontitle>
        <findex index="fn" spaces=" ">
          <indexterm index="fn" number="280" mergedindex="cp">
            \centering
          </indexterm>
        </findex>
        <cindex index="cp" spaces=" ">
          <indexterm index="cp" number="319">
            centering text, declaration for
          </indexterm>
        </cindex>
        <para>
          Synopsis:
        </para>
        <example endspaces=" ">
          <pre xml:space="preserve"Default handler: &lbrace;
>
            \centering ...
Default handler: &rbrace;
          </pre>
        </example>
        <noindent/>
        <para>
          or
        </para>
        <example endspaces=" ">
          <pre xml:space="preserve">
            \begin
Default handler: &lbrace;
            group
Default handler: &rbrace;
             \centering ... \end
Default handler: &lbrace;
            group
Default handler: &rbrace;
          </pre>
        </example>
        <para>
          Center the material in its scope. It is most often used inside an environment such as
          <code>
            figure
          </code>
          , or in a
          <code>
            parbox
          </code>
          .
        </para>
        <para>
          This example
Default handler: &textrsquo;
          s
          <code>
            \centering
          </code>
           declaration causes the graphic to be horizontally centered.
        </para>
        <example endspaces=" ">
          <pre xml:space="preserve">
            \begin
Default handler: &lbrace;
            figure
Default handler: &rbrace;
             \centering \includegraphics[width=0.6\textwidth]
Default handler: &lbrace;
            ctan_lion.png
Default handler: &rbrace;
             \caption
Default handler: &lbrace;
            CTAN Lion
Default handler: &rbrace;
             \label
Default handler: &lbrace;
            fig:CTANLion
Default handler: &rbrace;
             \end
Default handler: &lbrace;
            figure
Default handler: &rbrace;
          </pre>
        </example>
        <noindent/>
        <para>
          The scope of this
          <code>
            \centering
          </code>
           ends with the
          <code>
            \end
Default handler: &lbrace;
            figure
Default handler: &rbrace;
          </code>
          .
        </para>
        <para>
          Unlike the
          <code>
            center
          </code>
           environment, the
          <code>
            \centering
          </code>
           command does not add vertical space above and below the text. That
Default handler: &textrsquo;
          s its advantage in the above example; there is not an excess of space.
        </para>
        <para>
          It also does not start a new paragraph; it simply changes how
Default handler: &latex;
           formats paragraph units. If
          <code>
            ww
Default handler: &lbrace;
            \centering xx \\ yy
Default handler: &rbrace;
             zz
          </code>
           is surrounded by blank lines then
Default handler: &latex;
           will create a paragraph whose first line
          <samp>
            ww xx
          </samp>
           is centered and whose second line, not centered, contains
          <samp>
            yy zz
          </samp>
          . Usually what is desired is for the scope of the declaration to contain a blank line or the
          <code>
            \end
          </code>
           command of an environment such as
          <code>
            figure
          </code>
           or
          <code>
            table
          </code>
           that ends the paragraph unit. Thus, if
          <codeDefault handler: &lbrace;
>
            \centering xx \\ yy\par
Default handler: &rbrace;
             zz
          </code>
           is surrounded by blank lines then it makes a new paragraph with two centered lines
          <samp>
            xx
          </samp>
           and
          <samp>
            yy
          </samp>
          , followed by a new paragraph with
          <samp>
            zz
          </samp>
           that is formatted as usual.
        </para>
      </subsection>
    </section>
    <node name="description" spaces=" ">
      <nodename>
        description
      </nodename>
      <nodenext automatic="on">
        displaymath
      </nodenext>
      <nodeprev automatic="on">
        center
      </nodeprev>
      <nodeup automatic="on">
        Environments
      </nodeup>
    </node>
    <section spaces=" ">
      <sectiontitle>
        <code>
          description
        </code>
      </sectiontitle>
      <findex index="fn" spaces=" ">
        <indexterm index="fn" number="281" mergedindex="cp">
          <r>
            environment
          </r>
          ,
          <code>
            description
          </code>
        </indexterm>
      </findex>
      <findex index="fn" spaces=" ">
        <indexterm index="fn" number="282" mergedindex="cp">
          <code>
            description
          </code>
          <r>
            environment
          </r>
        </indexterm>
      </findex>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="320">
          labelled lists, creating
        </indexterm>
      </cindex>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="321">
          description lists, creating
        </indexterm>
      </cindex>
      <para>
        Synopsis:
      </para>
      <example endspaces=" ">
        <pre xml:space="preserve">
          \begin
Default handler: &lbrace;
          description
Default handler: &rbrace;
           \item[
          <var>
            label of first item
          </var>
          ]
          <var>
            text of first item
          </var>
           \item[
          <var>
            label of second item
          </var>
          ]
          <var>
            text of second item
          </var>
           ... \end
Default handler: &lbrace;
          description
Default handler: &rbrace;
        </pre>
      </example>
      <para>
        Environment to make a list of labeled items. Each item
Default handler: &textrsquo;
        s
        <var>
          label
        </var>
         is typeset in bold and is flush left, so that long labels continue into the first line of the item text. There must be at least one item; having none causes the
Default handler: &latex;
         error
        <samp>
          Something's wrong--perhaps a missing \item
        </samp>
        .
      </para>
      <para>
        This example shows the environment used for a sequence of definitions.
      </para>
      <example endspaces=" ">
        <pre xml:space="preserve">
          \begin
Default handler: &lbrace;
          description
Default handler: &rbrace;
           \item[lama] A priest. \item[llama] A beast. \end
Default handler: &lbrace;
          description
Default handler: &rbrace;
        </pre>
      </example>
      <noindent/>
      <para>
        The labels
        <samp>
          lama
        </samp>
         and
        <samp>
          llama
        </samp>
         are output in boldface, with the left edge on the left margin.
      </para>
      <findex index="fn" spaces=" ">
        <indexterm index="fn" number="283" mergedindex="cp">
          \item
        </indexterm>
      </findex>
      <para>
        Start list items with the
        <code>
          \item
        </code>
         command (
        <pxref label="_005citem">
          <xrefnodename>
            \item
          </xrefnodename>
        </pxref>
        ). Use the optional labels, as in
        <code>
          \item[Main point]
        </code>
        , because there is no sensible default. Following the
        <code>
          \item
        </code>
         is optional text, which may contain multiple paragraphs.
      </para>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="322">
          bold typewriter, avoiding
        </indexterm>
      </cindex>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="323">
          typewriter labels in lists
        </indexterm>
      </cindex>
      <para>
        Since the labels are in bold style, if the label text calls for a font change given in argument style (see
        <ref label="Font-styles">
          <xrefnodename>
            Font styles
          </xrefnodename>
        </ref>
        ) then it will come out bold. For instance, if the label text calls for typewriter with
        <code>
          \item[\texttt
Default handler: &lbrace;
          label text
Default handler: &rbrace;
          ]
        </code>
         then it will appear in bold typewriter, if that is available. The simplest way around this, in this example to get non-bold typewriter, is to use declarative style:
        <code>
          \item[
Default handler: &lbrace;
          \tt label text
Default handler: &rbrace;
          ]
        </code>
        . Similarly, get the standard roman font with
        <code>
          \item[
Default handler: &lbrace;
          \rm label text
Default handler: &rbrace;
          ]
        </code>
        .
      </para>
      <para>
        For other major
Default handler: &latex;
         labelled list environments, see
        <ref label="itemize">
          <xrefnodename>
            itemize
          </xrefnodename>
        </ref>
         and
        <ref label="enumerate">
          <xrefnodename>
            enumerate
          </xrefnodename>
        </ref>
        . Unlike those environments, nesting
        <code>
          description
        </code>
         environments does not change the default label; it is boldface and flush left at all levels.
      </para>
      <para>
        For information about list layout parameters, including the default values, and for information about customizing list layout, see
        <ref label="list">
          <xrefnodename>
            list
          </xrefnodename>
        </ref>
        . The package
        <code>
          enumitem
        </code>
         is useful for customizing lists.
      </para>
      <para>
        This example changes the description labels to small caps.
      </para>
      <example endspaces=" ">
        <pre xml:space="preserve">
          \renewcommand
Default handler: &lbrace;
          \descriptionlabel
Default handler: &rbrace;
          [1]
Default handler: &lbrace;
          %
Default handler: &lbrace;
          \hspace
Default handler: &lbrace;
          \labelsep
Default handler: &rbrace;
          \textsc
Default handler: &lbrace;
          #1
Default handler: &rbrace;
Default handler: &rbrace;
Default handler: &rbrace;
        </pre>
      </example>
    </section>
    <node name="displaymath" spaces=" ">
      <nodename>
        displaymath
      </nodename>
      <nodenext automatic="on">
        document
      </nodenext>
      <nodeprev automatic="on">
        description
      </nodeprev>
      <nodeup automatic="on">
        Environments
      </nodeup>
    </node>
    <section spaces=" ">
      <sectiontitle>
        <code>
          displaymath
        </code>
      </sectiontitle>
Default handler: <!-- c http://tex.stackexchange.com/questions/40492/what-are-the-differences-between-align-equation-and-displaymath -->
      <findex index="fn" spaces=" ">
        <indexterm index="fn" number="284" mergedindex="cp">
          <r>
            environment
          </r>
          ,
          <code>
            displaymath
          </code>
        </indexterm>
      </findex>
      <findex index="fn" spaces=" ">
        <indexterm index="fn" number="285" mergedindex="cp">
          <code>
            displaymath
          </code>
          <r>
            environment
          </r>
        </indexterm>
      </findex>
      <para>
        Synopsis:
      </para>
      <example endspaces=" ">
        <pre xml:space="preserve">
          \begin
Default handler: &lbrace;
          displaymath
Default handler: &rbrace;
          <var>
            mathematical text
          </var>
           \end
Default handler: &lbrace;
          displaymath
Default handler: &rbrace;
        </pre>
      </example>
      <para>
        Environment to typeset the
        <var>
          mathematical text
        </var>
         on its own line, in display style and centered. To make the text be flush-left use the global option
        <code>
          fleqn
        </code>
        ; see
        <ref label="Document-class-options">
          <xrefnodename>
            Document class options
          </xrefnodename>
        </ref>
        .
      </para>
      <para>
        In the
        <code>
          displaymath
        </code>
         environment no equation number is added to the math text. One way to get an equation number is to use the
        <code>
          equation
        </code>
         environment (
        <pxref label="equation">
          <xrefnodename>
            equation
          </xrefnodename>
        </pxref>
        ).
      </para>
      <paraDefault handler: &latex;
>
         will not break the
        <var>
          math text
        </var>
         across lines.
      </para>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="324">
          <r>
            package
          </r>
          ,
          <code>
            amsmath
          </code>
        </indexterm>
      </cindex>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="325">
          <code>
            amsmath
          </code>
          <r>
            package
          </r>
        </indexterm>
      </cindex>
      <para>
        Note that the
        <code>
          amsmath
        </code>
         package has significantly more extensive displayed equation facilities. For example, there are a number of ways in that package for having math text broken across lines.
      </para>
      <findex index="fn" spaces=" ">
        <indexterm index="fn" number="286" mergedindex="cp">
          \[...\]
          <r>
            display math
          </r>
        </indexterm>
      </findex>
      <para>
        The construct
        <code>
          \[
          <var>
            math
          </var>
           \]
        </code>
         is a synonym for the environment
        <code>
          \begin
Default handler: &lbrace;
          displaymath
Default handler: &rbrace;
          <var>
            math
          </var>
           \end
Default handler: &lbrace;
          displaymath
Default handler: &rbrace;
        </code>
         but the latter is easier to work with in the source; for instance, searching for a square bracket may get false positives but the word
        <code>
          displaymath
        </code>
         will likely be unique.
      </para>
      <findex index="fn" spaces=" ">
        <indexterm index="fn" number="287" mergedindex="cp">
          $$...$$
          <r>
            plain
Default handler: &tex;
             display math
          </r>
        </indexterm>
      </findex>
      <para>
        The construct
        <code>
          $$
          <var>
            math
          </var>
          $$
        </code>
         from Plain
Default handler: &nbsp;
Default handler: &tex;
         is sometimes used as a synonym for
Default handler: &latex;
Default handler: &textrsquo;
        s
        <code>
          displaymath
        </code>
        . It is not a synonym, and is not officially supported in
Default handler: &latex;
         at all;
        <code>
          $$
        </code>
         doesn
Default handler: &textrsquo;
        t support the
        <code>
          fleqn
        </code>
         option (
        <pxref label="Document-class-options">
          <xrefnodename>
            Document class options
          </xrefnodename>
        </pxref>
        ), has different vertical spacing, and doesn
Default handler: &textrsquo;
        t perform consistency checks.
      </para>
      <para>
        The output from this example is centered and alone on its line.
      </para>
      <example endspaces=" ">
        <pre xml:space="preserve">
          \begin
Default handler: &lbrace;
          displaymath
Default handler: &rbrace;
           \int_1^2 x^2\,dx=7/3 \end
Default handler: &lbrace;
          displaymath
Default handler: &rbrace;
        </pre>
      </example>
      <noindent/>
      <para>
        Also, the integral sign is larger than the inline version
        <code>
          \( \int_1^2 x^2\,dx=7/3 \)
        </code>
         produces.
      </para>
    </section>
    <node name="document" spaces=" ">
      <nodename>
        document
      </nodename>
      <nodenext automatic="on">
        enumerate
      </nodenext>
      <nodeprev automatic="on">
        displaymath
      </nodeprev>
      <nodeup automatic="on">
        Environments
      </nodeup>
    </node>
    <section spaces=" ">
      <sectiontitle>
        <code>
          document
        </code>
      </sectiontitle>
      <findex index="fn" spaces=" ">
        <indexterm index="fn" number="288" mergedindex="cp">
          <r>
            environment
          </r>
          ,
          <code>
            document
          </code>
        </indexterm>
      </findex>
      <findex index="fn" spaces=" ">
        <indexterm index="fn" number="289" mergedindex="cp">
          <code>
            document
          </code>
          <r>
            environment
          </r>
        </indexterm>
      </findex>
      <para>
        The
        <code>
          document
        </code>
         environment encloses the entire body of a document. It is required in every
Default handler: &latex;
         document.
        <xref label="Starting-and-ending">
          <xrefnodename>
            Starting and ending
          </xrefnodename>
        </xref>
        .
      </para>
      <menu endspaces=" ">
        <menuentry>
          <menuleadingtext>
            *
          </menuleadingtext>
          <menunode>
            \AtBeginDocument
          </menunode>
          <menuseparator>
            ::
          </menuseparator>
          <menudescription>
            <pre xml:space="preserve">
              Hook for commands at the start of the document.
            </pre>
          </menudescription>
        </menuentry>
        <menuentry>
          <menuleadingtext>
            *
          </menuleadingtext>
          <menunode>
            \AtEndDocument
          </menunode>
          <menuseparator>
            ::
          </menuseparator>
          <menudescription>
            <pre xml:space="preserve">
              Hook for commands at the end of the document.
            </pre>
          </menudescription>
        </menuentry>
      </menu>
      <node name="_005cAtBeginDocument" spaces=" ">
        <nodename>
          \AtBeginDocument
        </nodename>
        <nodenext automatic="on">
          \AtEndDocument
        </nodenext>
        <nodeup automatic="on">
          document
        </nodeup>
      </node>
      <subsection spaces=" ">
        <sectiontitle>
          <code>
            \AtBeginDocument
          </code>
        </sectiontitle>
        <findex index="fn" spaces=" ">
          <indexterm index="fn" number="290" mergedindex="cp">
            \AtBeginDocument
          </indexterm>
        </findex>
        <cindex index="cp" spaces=" ">
          <indexterm index="cp" number="326">
            beginning of document hook
          </indexterm>
        </cindex>
        <para>
          Synopsis:
        </para>
        <example endspaces=" ">
          <pre xml:space="preserve">
            \AtBeginDocument
Default handler: &lbrace;
            <var>
              code
            </var>
Default handler: &rbrace;
          </pre>
        </example>
        <para>
          Save
          <var>
            code
          </var>
           and execute it when
          <code>
            \begin
Default handler: &lbrace;
            document
Default handler: &rbrace;
          </code>
           is executed, at the very end of the preamble. The code is executed after the font selection tables have been set up, so the normal font for the document is the current font. However, the code is executed as part of the preamble so you cannot do any typesetting with it.
        </para>
        <para>
          You can issue this command more than once; the successive code lines will be executed in the order that you gave them.
        </para>
      </subsection>
      <node name="_005cAtEndDocument" spaces=" ">
        <nodename>
          \AtEndDocument
        </nodename>
        <nodeprev automatic="on">
          \AtBeginDocument
        </nodeprev>
        <nodeup automatic="on">
          document
        </nodeup>
      </node>
      <subsection spaces=" ">
        <sectiontitle>
          <code>
            \AtEndDocument
          </code>
        </sectiontitle>
        <findex index="fn" spaces=" ">
          <indexterm index="fn" number="291" mergedindex="cp">
            \AtEndDocument
          </indexterm>
        </findex>
        <cindex index="cp" spaces=" ">
          <indexterm index="cp" number="327">
            end of document hook
          </indexterm>
        </cindex>
        <para>
          Synopsis:
        </para>
        <example endspaces=" ">
          <pre xml:space="preserve">
            \AtEndDocument
Default handler: &lbrace;
            <var>
              code
            </var>
Default handler: &rbrace;
          </pre>
        </example>
        <para>
          Save
          <var>
            code
          </var>
           and execute it near the end of the document. Specifically, it is executed when
          <code>
            \end
Default handler: &lbrace;
            document
Default handler: &rbrace;
          </code>
           is executed, before the final page is finished and before any leftover floating environments are processed. If you want some of the code to be executed after these two processes then include a
          <code>
            \clearpage
          </code>
           at the appropriate point in
          <var>
            code
          </var>
          .
        </para>
        <para>
          You can issue this command more than once; the successive code lines will be executed in the order that you gave them.
        </para>
      </subsection>
    </section>
    <node name="enumerate" spaces=" ">
      <nodename>
        enumerate
      </nodename>
      <nodenext automatic="on">
        eqnarray
      </nodenext>
      <nodeprev automatic="on">
        document
      </nodeprev>
      <nodeup automatic="on">
        Environments
      </nodeup>
    </node>
    <section spaces=" ">
      <sectiontitle>
        <code>
          enumerate
        </code>
      </sectiontitle>
      <findex index="fn" spaces=" ">
        <indexterm index="fn" number="292" mergedindex="cp">
          <r>
            environment
          </r>
          ,
          <code>
            enumerate
          </code>
        </indexterm>
      </findex>
      <findex index="fn" spaces=" ">
        <indexterm index="fn" number="293" mergedindex="cp">
          <code>
            enumerate
          </code>
          <r>
            environment
          </r>
        </indexterm>
      </findex>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="328">
          lists of items, numbered
        </indexterm>
      </cindex>
      <para>
        Synopsis:
      </para>
      <example endspaces=" ">
        <pre xml:space="preserve">
          \begin
Default handler: &lbrace;
          enumerate
Default handler: &rbrace;
           \item[
          <var>
            optional label of first item
          </var>
          ]
          <var>
            text of first item
          </var>
           \item[
          <var>
            optional label of second item
          </var>
          ]
          <var>
            text of second item
          </var>
           ... \end
Default handler: &lbrace;
          enumerate
Default handler: &rbrace;
        </pre>
      </example>
      <para>
        Environment to produce a numbered list of items. The format of the label numbering depends on the nesting level of this environment; see below. The default top-level numbering is
        <samp>
          1.
        </samp>
        ,
        <samp>
          2.
        </samp>
        , etc. Each
        <code>
          enumerate
        </code>
         list environment must have at least one item; having none causes the
Default handler: &latex;
         error
        <samp>
          Something's wrong--perhaps a missing \item
        </samp>
        .
      </para>
      <para>
        This example gives the first two finishers in the 1908 Olympic marathon. As a top-level list the labels would come out as
        <samp>
          1.
        </samp>
         and
        <samp>
          2.
        </samp>
        .
      </para>
      <example endspaces=" ">
        <pre xml:space="preserve">
          \begin
Default handler: &lbrace;
          enumerate
Default handler: &rbrace;
           \item Johnny Hayes (USA) \item Charles Hefferon (RSA) \end
Default handler: &lbrace;
          enumerate
Default handler: &rbrace;
        </pre>
      </example>
      <findex index="fn" spaces=" ">
        <indexterm index="fn" number="294" mergedindex="cp">
          \item
        </indexterm>
      </findex>
      <para>
        Start list items with the
        <code>
          \item
        </code>
         command (
        <pxref label="_005citem">
          <xrefnodename>
            \item
          </xrefnodename>
        </pxref>
        ). If you give
        <code>
          \item
        </code>
         an optional argument by following it with square brackets, as in
        <code>
          \item[Interstitial label]
        </code>
        , then the next item will continue the interrupted sequence (
        <pxref label="_005citem">
          <xrefnodename>
            \item
          </xrefnodename>
        </pxref>
        ). That is, you will get labels like
        <samp>
          1.
        </samp>
        , then
        <samp>
          Interstitial label
        </samp>
        , then
        <samp>
          2.
        </samp>
        . Following the
        <code>
          \item
        </code>
         is optional text, which may contain multiple paragraphs.
      </para>
      <para>
        Enumerations may be nested within other
        <code>
          enumerate
        </code>
         environments, or within any paragraph-making environment such as
        <code>
          itemize
        </code>
         (
        <pxref label="itemize">
          <xrefnodename>
            itemize
          </xrefnodename>
        </pxref>
        ), up to four levels deep. This gives
Default handler: &latex;
Default handler: &textrsquo;
        s default for the format at each nesting level, where 1 is the top level, the outermost level.
      </para>
      <enumerate first="1" endspaces=" ">
        <listitem>
          <para>
            arabic number followed by a period:
            <samp>
              1.
            </samp>
            ,
            <samp>
              2.
            </samp>
            ,
Default handler: &nbsp;
Default handler: &dots;
          </para>
        </listitem>
        <listitem>
          <para>
            lowercase letter inside parentheses:
            <samp>
              (a)
            </samp>
            ,
            <samp>
              (b)
            </samp>
Default handler: &nbsp;
Default handler: &dots;
          </para>
        </listitem>
        <listitem>
          <para>
            lowercase roman numeral followed by a period:
            <samp>
              i.
            </samp>
            ,
            <samp>
              ii.
            </samp>
            ,
Default handler: &nbsp;
Default handler: &dots;
          </para>
        </listitem>
        <listitem>
          <para>
            uppercase letter followed by a period:
            <samp>
              A.
            </samp>
            ,
            <samp>
              B.
            </samp>
            ,
Default handler: &nbsp;
Default handler: &dots;
          </para>
        </listitem>
      </enumerate>
      <findex index="fn" spaces=" ">
        <indexterm index="fn" number="295" mergedindex="cp">
          \enumi
        </indexterm>
      </findex>
      <findex index="fn" spaces=" ">
        <indexterm index="fn" number="296" mergedindex="cp">
          \enumii
        </indexterm>
      </findex>
      <findex index="fn" spaces=" ">
        <indexterm index="fn" number="297" mergedindex="cp">
          \enumiii
        </indexterm>
      </findex>
      <findex index="fn" spaces=" ">
        <indexterm index="fn" number="298" mergedindex="cp">
          \enumiv
        </indexterm>
      </findex>
      <anchor name="enumerate-enumi">
        enumerate enumi
      </anchor>
      <anchor name="enumerate-enumii">
        enumerate enumii
      </anchor>
      <anchor name="enumerate-enumiii">
        enumerate enumiii
      </anchor>
      <anchor name="enumerate-enumiv">
        enumerate enumiv
      </anchor>
      <para>
        The
        <code>
          enumerate
        </code>
         environment uses the counters
        <code>
          \enumi
        </code>
         through
        <code>
          \enumiv
        </code>
         (
        <pxref label="Counters">
          <xrefnodename>
            Counters
          </xrefnodename>
        </pxref>
        ).
      </para>
      <para>
        For other major
Default handler: &latex;
         labeled list environments, see
        <ref label="description">
          <xrefnodename>
            description
          </xrefnodename>
        </ref>
         and
        <ref label="itemize">
          <xrefnodename>
            itemize
          </xrefnodename>
        </ref>
        . For information about list layout parameters, including the default values, and for information about customizing list layout, see
        <ref label="list">
          <xrefnodename>
            list
          </xrefnodename>
        </ref>
        . The package
        <code>
          enumitem
        </code>
         is useful for customizing lists.
      </para>
      <findex index="fn" spaces=" ">
        <indexterm index="fn" number="299" mergedindex="cp">
          \labelenumi
        </indexterm>
      </findex>
      <findex index="fn" spaces=" ">
        <indexterm index="fn" number="300" mergedindex="cp">
          \labelenumii
        </indexterm>
      </findex>
      <findex index="fn" spaces=" ">
        <indexterm index="fn" number="301" mergedindex="cp">
          \labelenumiii
        </indexterm>
      </findex>
      <findex index="fn" spaces=" ">
        <indexterm index="fn" number="302" mergedindex="cp">
          \labelenumiv
        </indexterm>
      </findex>
      <anchor name="enumerate-labelenumi">
        enumerate labelenumi
      </anchor>
      <anchor name="enumerate-labelenumii">
        enumerate labelenumii
      </anchor>
      <anchor name="enumerate-labelenumiii">
        enumerate labelenumiii
      </anchor>
      <anchor name="enumerate-labelenumiv">
        enumerate labelenumiv
      </anchor>
      <para>
        To change the format of the label use
        <code>
          \renewcommand
        </code>
         (
        <pxref label="_005cnewcommand-_0026-_005crenewcommand">
          <xrefnodename>
            \newcommand
            &
             \renewcommand
          </xrefnodename>
        </pxref>
        ) on the commands
        <code>
          \labelenumi
        </code>
         through
        <code>
          \labelenumiv
        </code>
        . For instance, this first level list will be labelled with uppercase letters, in boldface, and without a trailing period.
      </para>
      <findex index="fn" spaces=" ">
        <indexterm index="fn" number="303" mergedindex="cp">
          \Alph
          <r>
            example
          </r>
        </indexterm>
      </findex>
      <example endspaces=" ">
        <pre xml:space="preserve">
          \renewcommand
Default handler: &lbrace;
          \labelenumi
Default handler: &rbrace;
Default handler: &lbrace;
          \textbf
Default handler: &lbrace;
          \Alph
Default handler: &lbrace;
          enumi
Default handler: &rbrace;
Default handler: &rbrace;
Default handler: &rbrace;
           \begin
Default handler: &lbrace;
          enumerate
Default handler: &rbrace;
           \item Shows as boldface A \item Shows as boldface B \end
Default handler: &lbrace;
          enumerate
Default handler: &rbrace;
        </pre>
      </example>
      <para>
        For a list of counter-labeling commands see
        <ref label="_005calph-_005cAlph-_005carabic-_005croman-_005cRoman-_005cfnsymbol">
          <xrefnodename>
            \alph \Alph \arabic \roman \Roman \fnsymbol
          </xrefnodename>
        </ref>
        .
      </para>
    </section>
    <node name="eqnarray" spaces=" ">
      <nodename>
        eqnarray
      </nodename>
      <nodenext automatic="on">
        equation
      </nodenext>
      <nodeprev automatic="on">
        enumerate
      </nodeprev>
      <nodeup automatic="on">
        Environments
      </nodeup>
    </node>
    <section spaces=" ">
      <sectiontitle>
        <code>
          eqnarray
        </code>
      </sectiontitle>
      <findex index="fn" spaces=" ">
        <indexterm index="fn" number="304" mergedindex="cp">
          <r>
            environment
          </r>
          ,
          <code>
            eqnarray
          </code>
        </indexterm>
      </findex>
      <findex index="fn" spaces=" ">
        <indexterm index="fn" number="305" mergedindex="cp">
          <code>
            eqnarray
          </code>
          <r>
            environment
          </r>
        </indexterm>
      </findex>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="329">
          equations, aligning
        </indexterm>
      </cindex>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="330">
          aligning equations
        </indexterm>
      </cindex>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="331">
          align
          <r>
            environment, from
            <code>
              amsmath
            </code>
          </r>
        </indexterm>
      </cindex>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="332">
          amsmath
          <r>
            package, replacing
            <code>
              eqnarray
            </code>
          </r>
        </indexterm>
      </cindex>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="333">
          Madsen, Lars
        </indexterm>
      </cindex>
      <para>
        The
        <code>
          eqnarray
        </code>
         environment is obsolete. It has infelicities, including spacing that is inconsistent with other mathematics elements. (See
Default handler: &textldquo;
        Avoid eqnarray!
Default handler: &textrdquo;
Default handler: &noeos;
         by Lars Madsen
        <url>
          <urefurl>
            https://tug.org/TUGboat/tb33-1/tb103madsen.pdf
          </urefurl>
        </url>
        ). New documents should include the
        <code>
          amsmath
        </code>
         package and use the displayed mathematics environments provided there, such as the
        <code>
          align
        </code>
         environment. We include a description only for completeness and for working with old documents.
      </para>
      <para>
        Synopsis:
      </para>
      <example endspaces=" ">
        <pre xml:space="preserve">
          \begin
Default handler: &lbrace;
          eqnarray
Default handler: &rbrace;
          <var>
            first formula left
          </var>
          &
          <var>
            first formula middle
          </var>
          &
          <var>
            first formula right
          </var>
           \\ ... \end
Default handler: &lbrace;
          eqnarray
Default handler: &rbrace;
        </pre>
      </example>
      <noindent/>
      <para>
        or
      </para>
      <example endspaces=" ">
        <pre xml:space="preserve">
          \begin
Default handler: &lbrace;
          eqnarray*
Default handler: &rbrace;
          <var>
            first formula left
          </var>
          &
          <var>
            first formula middle
          </var>
          &
          <var>
            first formula right
          </var>
           \\ ... \end
Default handler: &lbrace;
          eqnarray*
Default handler: &rbrace;
        </pre>
      </example>
      <findex index="fn" spaces=" ">
        <indexterm index="fn" number="306" mergedindex="cp">
          \\
          <r>
            (for
            <code>
              eqnarray
            </code>
            )
          </r>
        </indexterm>
      </findex>
      <para>
        Display a sequence of equations or inequalities. The left and right sides are typeset in display mode, while the middle is typeset in text mode.
      </para>
      <para>
        It is similar to a three-column
        <code>
          array
        </code>
         environment, with items within a row separated by an ampersand
Default handler: &nbsp;
        (
        <code>
          &
        </code>
        ), and with rows separated by double backslash
Default handler: &nbsp;
        <code>
          \\
        </code>
        ).
        <findex index="fn" spaces=" ">
          <indexterm index="fn" number="307" mergedindex="cp">
            \\*
            <r>
              (for
              <code>
                eqnarray
              </code>
              )
            </r>
          </indexterm>
        </findex>
         The starred form of line break (
        <code>
          \\*
        </code>
        ) can also be used to separate equations, and will disallow a page break there (
        <pxref label="_005c_005c">
          <xrefnodename>
            \\
          </xrefnodename>
        </pxref>
        ).
      </para>
      <findex index="fn" spaces=" ">
        <indexterm index="fn" number="308" mergedindex="cp">
          \nonumber
        </indexterm>
      </findex>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="334">
          equation numbers, omitting
        </indexterm>
      </cindex>
      <para>
        The unstarred form
        <code>
          eqnarray
        </code>
         places an equation number on every line (using the
        <code>
          equation
        </code>
         counter), unless that line contains a
        <code>
          \nonumber
        </code>
         command. The starred form
        <code>
          eqnarray*
        </code>
         omits equation numbering, while otherwise being the same.
      </para>
      <findex index="fn" spaces=" ">
        <indexterm index="fn" number="309" mergedindex="cp">
          \lefteqn
        </indexterm>
      </findex>
      <para>
        The command
        <code>
          \lefteqn
        </code>
         is used for splitting long formulas across lines. It typesets its argument in display style flush left in a box of zero width.
      </para>
      <para>
        This example shows three lines. The first two lines make an inequality, while the third line has not entry on the left side.
      </para>
      <example endspaces=" ">
        <pre xml:space="preserve">
          \begin
Default handler: &lbrace;
          eqnarray*
Default handler: &rbrace;
           \lefteqn
Default handler: &lbrace;
          x_1+x_2+\cdots+x_n
Default handler: &rbrace;
           \\
          &
          \leq
          &
          y_1+y_2+\cdots+y_n \\
          &
          =
          &
          z+y_3+\cdots+y_n \end
Default handler: &lbrace;
          eqnarray*
Default handler: &rbrace;
        </pre>
      </example>
    </section>
    <node name="equation" spaces=" ">
      <nodename>
        equation
      </nodename>
      <nodenext automatic="on">
        figure
      </nodenext>
      <nodeprev automatic="on">
        eqnarray
      </nodeprev>
      <nodeup automatic="on">
        Environments
      </nodeup>
    </node>
    <section spaces=" ">
      <sectiontitle>
        <code>
          equation
        </code>
      </sectiontitle>
      <findex index="fn" spaces=" ">
        <indexterm index="fn" number="310" mergedindex="cp">
          <r>
            environment
          </r>
          ,
          <code>
            equation
          </code>
        </indexterm>
      </findex>
      <findex index="fn" spaces=" ">
        <indexterm index="fn" number="311" mergedindex="cp">
          <code>
            equation
          </code>
          <r>
            environment
          </r>
        </indexterm>
      </findex>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="335">
          equations, environment for
        </indexterm>
      </cindex>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="336">
          formulas, environment for
        </indexterm>
      </cindex>
      <para>
        Synopsis:
      </para>
      <example endspaces=" ">
        <pre xml:space="preserve">
          \begin
Default handler: &lbrace;
          equation
Default handler: &rbrace;
          <var>
            mathematical text
          </var>
           \end
Default handler: &lbrace;
          equation
Default handler: &rbrace;
        </pre>
      </example>
      <para>
        The same as a
        <code>
          displaymath
        </code>
         environment (
        <pxref label="displaymath">
          <xrefnodename>
            displaymath
          </xrefnodename>
        </pxref>
        ) except that
Default handler: &latex;
         puts an equation number flush to the right margin. The equation number is generated using the
        <code>
          equation
        </code>
         counter.
      </para>
      <para>
        You should have no blank lines between
        <code>
          \begin
Default handler: &lbrace;
          equation
Default handler: &rbrace;
        </code>
         and
        <code>
          \end
Default handler: &lbrace;
          equation
Default handler: &rbrace;
        </code>
        , or
Default handler: &latex;
         will tell you that there is a missing dollar sign.
      </para>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="337">
          <r>
            package
          </r>
          ,
          <code>
            amsmath
          </code>
        </indexterm>
      </cindex>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="338">
          <code>
            amsmath
          </code>
          <r>
            package
          </r>
        </indexterm>
      </cindex>
      <para>
        The package
        <code>
          amsmath
        </code>
         package has extensive displayed equation facilities. New documents should include this package.
      </para>
    </section>
    <node name="figure" spaces=" ">
      <nodename>
        figure
      </nodename>
      <nodenext automatic="on">
        filecontents
      </nodenext>
      <nodeprev automatic="on">
        equation
      </nodeprev>
      <nodeup automatic="on">
        Environments
      </nodeup>
    </node>
    <section spaces=" ">
      <sectiontitle>
        <code>
          figure
        </code>
      </sectiontitle>
      <findex index="fn" spaces=" ">
        <indexterm index="fn" number="312" mergedindex="cp">
          <r>
            environment
          </r>
          ,
          <code>
            figure
          </code>
        </indexterm>
      </findex>
      <findex index="fn" spaces=" ">
        <indexterm index="fn" number="313" mergedindex="cp">
          <code>
            figure
          </code>
          <r>
            environment
          </r>
        </indexterm>
      </findex>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="339">
          inserting figures
        </indexterm>
      </cindex>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="340">
          figures, inserting
        </indexterm>
      </cindex>
      <para>
        Synopsis:
      </para>
      <example endspaces=" ">
        <pre xml:space="preserve">
          \begin
Default handler: &lbrace;
          figure
Default handler: &rbrace;
          [
          <var>
            placement
          </var>
          ]
          <var>
            figure body
          </var>
           \caption[
          <var>
            loftitle
          </var>
          ]
Default handler: &lbrace;
          <var>
            title
          </var>
Default handler: &rbrace;
           % optional \label
Default handler: &lbrace;
          <var>
            label
Default handler: &rbrace;
          </var>
           % optional \end
Default handler: &lbrace;
          figure
Default handler: &rbrace;
        </pre>
      </example>
      <noindent/>
      <para>
        or:
      </para>
      <example endspaces=" ">
        <pre xml:space="preserve">
          \begin
Default handler: &lbrace;
          figure*
Default handler: &rbrace;
          [
          <var>
            placement
          </var>
          ]
          <var>
            figure body
          </var>
           \caption[
          <var>
            loftitle
          </var>
          ]
Default handler: &lbrace;
          <var>
            title
          </var>
Default handler: &rbrace;
           % optional \label
Default handler: &lbrace;
          <var>
            label
Default handler: &rbrace;
          </var>
           % optional \end
Default handler: &lbrace;
          figure*
Default handler: &rbrace;
        </pre>
      </example>
      <para>
        Figures are for material that is not part of the normal text. An example is material that you cannot have split between two pages, such as a graphic. Because of this,
Default handler: &latex;
         does not typeset figures in sequence with normal text but instead
Default handler: &textldquo;
        floats
Default handler: &textrdquo;
         them to a convenient place, such as the top of a following page (
        <pxref label="Floats">
          <xrefnodename>
            Floats
          </xrefnodename>
        </pxref>
        ).
      </para>
      <para>
        The
        <var>
          figure body
        </var>
         can consist of imported graphics (
        <pxref label="Graphics">
          <xrefnodename>
            Graphics
          </xrefnodename>
        </pxref>
        ), or text,
Default handler: &latex;
         commands, etc. It is typeset in a
        <code>
          parbox
        </code>
         of width
        <code>
          \textwidth
        </code>
        .
      </para>
      <para>
        The possible values of
        <var>
          placement
        </var>
         are
        <code>
          h
        </code>
         for
        <samp>
          here
        </samp>
        ,
        <code>
          t
        </code>
         for
        <samp>
          top
        </samp>
        ,
        <code>
          b
        </code>
         for
        <samp>
          bottom
        </samp>
        , and
        <code>
          p
        </code>
         for
        <samp>
          on a separate page of floats
        </samp>
        . For the effect of these options on the float placement algorithm, see
        <ref label="Floats">
          <xrefnodename>
            Floats
          </xrefnodename>
        </ref>
        .
      </para>
      <para>
        The starred form
        <code>
          figure*
        </code>
         is used when a document is in double-column mode (
        <pxref label="_005ctwocolumn">
          <xrefnodename>
            \twocolumn
          </xrefnodename>
        </pxref>
        ). It produces a figure that spans both columns, at the top of the page. To add the possibility of placing at a page bottom see the discussion of
        <var>
          placement
        </var>
        <code>
          b
        </code>
         in
        <ref label="Floats">
          <xrefnodename>
            Floats
          </xrefnodename>
        </ref>
        .
      </para>
      <findex index="fn" spaces=" ">
        <indexterm index="fn" number="314" mergedindex="cp">
          \caption
        </indexterm>
      </findex>
      <para>
        The label is optional; it is used for cross references (
        <pxref label="Cross-references">
          <xrefnodename>
            Cross references
          </xrefnodename>
        </pxref>
        ). The optional
        <code>
          \caption
        </code>
         command specifies caption text for the figure (
        <pxref label="_005ccaption">
          <xrefnodename>
            \caption
          </xrefnodename>
        </pxref>
        ). By default it is numbered. If
        <var>
          loftitle
        </var>
         is present, it is used in the list of figures instead of
        <var>
          title
        </var>
         (
        <pxref label="Table-of-contents-etc_002e">
          <xrefnodename>
            Table of contents etc.
          </xrefnodename>
        </pxref>
        ).
      </para>
      <para>
        This example makes a figure out of a graphic.
Default handler: &latex;
         will place that graphic and its caption at the top of a page or, if it is pushed to the end of the document, on a page of floats.
      </para>
      <example endspaces=" ">
        <pre xml:space="preserve">
          \usepackage
Default handler: &lbrace;
          graphicx
Default handler: &rbrace;
           % in preamble ... \begin
Default handler: &lbrace;
          figure
Default handler: &rbrace;
          [t] \centering \includegraphics[width=0.5\textwidth]
Default handler: &lbrace;
          CTANlion.png
Default handler: &rbrace;
           \caption
Default handler: &lbrace;
          The CTAN lion, by Duane Bibby
Default handler: &rbrace;
           \end
Default handler: &lbrace;
          figure
Default handler: &rbrace;
        </pre>
      </example>
    </section>
    <node name="filecontents" spaces=" ">
      <nodename>
        filecontents
      </nodename>
      <nodenext automatic="on">
        flushleft
      </nodenext>
      <nodeprev automatic="on">
        figure
      </nodeprev>
      <nodeup automatic="on">
        Environments
      </nodeup>
    </node>
    <section spaces=" ">
      <sectiontitle>
        <code>
          filecontents
        </code>
      </sectiontitle>
      <findex index="fn" spaces=" ">
        <indexterm index="fn" number="315" mergedindex="cp">
          <r>
            environment
          </r>
          ,
          <code>
            filecontents
          </code>
        </indexterm>
      </findex>
      <findex index="fn" spaces=" ">
        <indexterm index="fn" number="316" mergedindex="cp">
          <code>
            filecontents
          </code>
          <r>
            environment
          </r>
        </indexterm>
      </findex>
      <findex index="fn" spaces=" ">
        <indexterm index="fn" number="317" mergedindex="cp">
          <r>
            environment
          </r>
          ,
          <code>
            filecontents*
          </code>
        </indexterm>
      </findex>
      <findex index="fn" spaces=" ">
        <indexterm index="fn" number="318" mergedindex="cp">
          <code>
            filecontents*
          </code>
          <r>
            environment
          </r>
        </indexterm>
      </findex>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="341">
          external files, writing
        </indexterm>
      </cindex>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="342">
          writing external files
        </indexterm>
      </cindex>
      <para>
        Synopsis:
      </para>
      <example endspaces=" ">
        <pre xml:space="preserve">
          \begin
Default handler: &lbrace;
          filecontents
Default handler: &rbrace;
          [
          <var>
            option
          </var>
          ]
Default handler: &lbrace;
          <var>
            filename
          </var>
Default handler: &rbrace;
          <var>
            text
          </var>
           \end
Default handler: &lbrace;
          filecontents
Default handler: &rbrace;
        </pre>
      </example>
      <noindent/>
      <para>
        or
      </para>
      <example endspaces=" ">
        <pre xml:space="preserve">
          \begin
Default handler: &lbrace;
          filecontents*
Default handler: &rbrace;
          [
          <var>
            option
          </var>
          ]
Default handler: &lbrace;
          <var>
            filename
          </var>
Default handler: &rbrace;
          <var>
            text
          </var>
           \end
Default handler: &lbrace;
          filecontents*
Default handler: &rbrace;
        </pre>
      </example>
      <para>
        Create a file named
        <var>
          filename
        </var>
         in the current directory (or the output directory, if specified;
        <pxref label="output-directory">
          <xrefnodename>
            output directory
          </xrefnodename>
        </pxref>
        ) and write
        <var>
          text
        </var>
         to it. By default, an existing file is not overwritten.
      </para>
      <para>
        The unstarred version of the environment
        <code>
          filecontents
        </code>
         prefixes the content of the created file with a header of
Default handler: &tex;
         comments; see the example below. The starred version
        <code>
          filecontents*
        </code>
         does not include the header.
      </para>
      <para>
        The possible options are:
      </para>
      <table commandarg="code" spaces=" " endspaces=" ">
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                force
              </itemformat>
            </item>
            <itemx spaces=" ">
              <itemformat command="code">
                overwrite
              </itemformat>
            </itemx>
          </tableterm>
          <tableitem>
            <cindex index="cp" spaces=" ">
              <indexterm index="cp" number="343">
                <code>
                  force
                </code>
                 option for
                <code>
                  filecontents
                </code>
              </indexterm>
            </cindex>
            <cindex index="cp" spaces=" ">
              <indexterm index="cp" number="344">
                <code>
                  overwrite
                </code>
                 option for
                <code>
                  filecontents
                </code>
              </indexterm>
            </cindex>
            <para>
              Overwrite an existing file.
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                noheader
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <cindex index="cp" spaces=" ">
              <indexterm index="cp" number="345">
                <code>
                  noheader
                </code>
                 option for
                <code>
                  filecontents
                </code>
              </indexterm>
            </cindex>
            <para>
              Omit the header. Equivalent to using
              <code>
                filecontents*
              </code>
              .
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                nosearch
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <cindex index="cp" spaces=" ">
              <indexterm index="cp" number="346">
                <code>
                  nosearch
                </code>
                 option for
                <code>
                  filecontents
                </code>
              </indexterm>
            </cindex>
            <para>
              Only check the current directory (and the output directory, if specified) for an existing file, not the entire search path.
            </para>
          </tableitem>
        </tableentry>
      </table>
      <para>
        These options were added in a 2019 release of
Default handler: &latex;
        .
      </para>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="347">
          self-contained sources
        </indexterm>
      </cindex>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="348">
          source files, making self-contained
        </indexterm>
      </cindex>
      <para>
        This environment can be used anywhere in the preamble, although it often appears before the
        <code>
          \documentclass
        </code>
         command. It is commonly used to create a
        <code>
          .bib
        </code>
         or other such data file from the main document source, to make the source file self-contained. Similarly, it can be used to create a custom style or class file, again making the source self-contained.
      </para>
      <para>
        For example, this document:
      </para>
      <example endspaces=" ">
        <pre xml:space="preserve">
          \documentclass
Default handler: &lbrace;
          article
Default handler: &rbrace;
           \begin
Default handler: &lbrace;
          filecontents
Default handler: &rbrace;
Default handler: &lbrace;
          JH.sty
Default handler: &rbrace;
           \newcommand
Default handler: &lbrace;
          \myname
Default handler: &rbrace;
Default handler: &lbrace;
          Jim Hef
Default handler: &lbrace;
Default handler: &rbrace;
          feron
Default handler: &rbrace;
           \end
Default handler: &lbrace;
          filecontents
Default handler: &rbrace;
           \usepackage
Default handler: &lbrace;
          JH
Default handler: &rbrace;
           \begin
Default handler: &lbrace;
          document
Default handler: &rbrace;
           Article by \myname. \end
Default handler: &lbrace;
          document
Default handler: &rbrace;
        </pre>
      </example>
      <noindent/>
      <para>
        produces this file
        <file>
          JH.sty
        </file>
        :
      </para>
      <example endspaces=" ">
        <pre xml:space="preserve">
          %% LaTeX2e file `JH.sty' %% generated by the `filecontents' environment %% from source `test' on 2015/10/12. %% \newcommand
Default handler: &lbrace;
          \myname
Default handler: &rbrace;
Default handler: &lbrace;
          Jim Hef
Default handler: &lbrace;
Default handler: &rbrace;
          feron
Default handler: &rbrace;
        </pre>
      </example>
    </section>
    <node name="flushleft" spaces=" ">
      <nodename>
        flushleft
      </nodename>
      <nodenext automatic="on">
        flushright
      </nodenext>
      <nodeprev automatic="on">
        filecontents
      </nodeprev>
      <nodeup automatic="on">
        Environments
      </nodeup>
    </node>
    <section spaces=" ">
      <sectiontitle>
        <code>
          flushleft
        </code>
      </sectiontitle>
      <findex index="fn" spaces=" ">
        <indexterm index="fn" number="319" mergedindex="cp">
          <r>
            environment
          </r>
          ,
          <code>
            flushleft
          </code>
        </indexterm>
      </findex>
      <findex index="fn" spaces=" ">
        <indexterm index="fn" number="320" mergedindex="cp">
          <code>
            flushleft
          </code>
          <r>
            environment
          </r>
        </indexterm>
      </findex>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="349">
          left-justifying text, environment for
        </indexterm>
      </cindex>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="350">
          ragged right text, environment for
        </indexterm>
      </cindex>
      <para>
        Synopsis:
      </para>
      <example endspaces=" ">
        <pre xml:space="preserve">
          \begin
Default handler: &lbrace;
          flushleft
Default handler: &rbrace;
          <var>
            line1
          </var>
           \\
          <var>
            line2
          </var>
           \\ ... \end
Default handler: &lbrace;
          flushleft
Default handler: &rbrace;
        </pre>
      </example>
      <findex index="fn" spaces=" ">
        <indexterm index="fn" number="321" mergedindex="cp">
          \\
          <r>
            (for
            <code>
              flushleft
            </code>
            )
          </r>
        </indexterm>
      </findex>
      <para>
        An environment that creates a paragraph whose lines are flush to the left-hand margin, and ragged right. If you have lines that are too long then
Default handler: &latex;
         will linebreak them in a way that avoids hyphenation and stretching or shrinking interword spaces. To force a new line use a double backslash,
        <code>
          \\
        </code>
        . For the declaration form see
Default handler: &nbsp;
        <ref label="_005craggedright">
          <xrefnodename>
            \raggedright
          </xrefnodename>
        </ref>
        .
      </para>
      <para>
        This creates a box of text that is at most 3 inches wide, with the text flush left and ragged right.
      </para>
      <example endspaces=" ">
        <pre xml:space="preserve">
          \noindent\begin
Default handler: &lbrace;
          minipage
Default handler: &rbrace;
Default handler: &lbrace;
          3in
Default handler: &rbrace;
           \begin
Default handler: &lbrace;
          flushleft
Default handler: &rbrace;
           A long sentence that will be broken by \LaTeX
Default handler: &lbrace;
Default handler: &rbrace;
           at a convenient spot. \\ And, a fresh line forced by the double backslash. \end
Default handler: &lbrace;
          flushleft
Default handler: &rbrace;
           \end
Default handler: &lbrace;
          minipage
Default handler: &rbrace;
        </pre>
      </example>
      <menu endspaces=" ">
        <menuentry>
          <menuleadingtext>
            *
          </menuleadingtext>
          <menunode>
            \raggedright
          </menunode>
          <menuseparator>
            ::
          </menuseparator>
          <menudescription>
            <pre xml:space="preserve">
              Declaration form of the
              <code>
                flushleft
              </code>
               environment.
            </pre>
          </menudescription>
        </menuentry>
      </menu>
      <node name="_005craggedright" spaces=" ">
        <nodename>
          \raggedright
        </nodename>
        <nodeup automatic="on">
          flushleft
        </nodeup>
      </node>
      <subsection spaces=" ">
        <sectiontitle>
          <code>
            \raggedright
          </code>
        </sectiontitle>
        <findex index="fn" spaces=" ">
          <indexterm index="fn" number="322" mergedindex="cp">
            \raggedright
          </indexterm>
        </findex>
        <cindex index="cp" spaces=" ">
          <indexterm index="cp" number="351">
            ragged right text
          </indexterm>
        </cindex>
        <cindex index="cp" spaces=" ">
          <indexterm index="cp" number="352">
            left-justifying text
          </indexterm>
        </cindex>
        <cindex index="cp" spaces=" ">
          <indexterm index="cp" number="353">
            justification, ragged right
          </indexterm>
        </cindex>
        <para>
          Synopses:
        </para>
        <example endspaces=" ">
          <pre xml:space="preserve"Default handler: &lbrace;
>
            \raggedright ...
Default handler: &rbrace;
          </pre>
        </example>
        <noindent/>
        <para>
          or
        </para>
        <example endspaces=" ">
          <pre xml:space="preserve">
            \begin
Default handler: &lbrace;
            <var>
              environment
            </var>
Default handler: &rbrace;
             \raggedright ... \end
Default handler: &lbrace;
            <var>
              environment
            </var>
Default handler: &rbrace;
          </pre>
        </example>
        <para>
          A declaration which causes lines to be flush to the left margin and ragged right. It can be used inside an
          <var>
            environment
          </var>
           such as
          <code>
            quote
          </code>
           or in a
          <code>
            parbox
          </code>
          . For the environment form see
Default handler: &nbsp;
          <ref label="flushleft">
            <xrefnodename>
              flushleft
            </xrefnodename>
          </ref>
          .
        </para>
        <para>
          Unlike the
          <code>
            flushleft
          </code>
           environment, the
          <code>
            \raggedright
          </code>
           command does not start a new paragraph; it only changes how
Default handler: &latex;
           formats paragraph units. To affect a paragraph unit
Default handler: &textrsquo;
          s format, the scope of the declaration must contain the blank line or
          <code>
            \end
          </code>
           command that ends the paragraph unit.
        </para>
        <para>
          Here
          <code>
            \raggedright
          </code>
           in each second column keeps
Default handler: &latex;
           from doing awkward typesetting to fit the text into the narrow column. Note that
          <code>
            \raggedright
          </code>
           is inside the curly braces
          <codeDefault handler: &lbrace;
>
            ...
Default handler: &rbrace;
          </code>
           to delimit its effect.
        </para>
        <example endspaces=" ">
          <pre xml:space="preserve">
            \begin
Default handler: &lbrace;
            tabular
Default handler: &rbrace;
Default handler: &lbrace;
            rp
Default handler: &lbrace;
            2in
Default handler: &rbrace;
Default handler: &rbrace;
             Team alpha
            &
Default handler: &lbrace;
            \raggedright This team does all the real work.
Default handler: &rbrace;
             \\ Team beta
            &
Default handler: &lbrace;
            \raggedright This team ensures that the water cooler is never empty.
Default handler: &rbrace;
             \\ \end
Default handler: &lbrace;
            tabular
Default handler: &rbrace;
          </pre>
        </example>
      </subsection>
    </section>
    <node name="flushright" spaces=" ">
      <nodename>
        flushright
      </nodename>
      <nodenext automatic="on">
        itemize
      </nodenext>
      <nodeprev automatic="on">
        flushleft
      </nodeprev>
      <nodeup automatic="on">
        Environments
      </nodeup>
    </node>
    <section spaces=" ">
      <sectiontitle>
        <code>
          flushright
        </code>
      </sectiontitle>
      <findex index="fn" spaces=" ">
        <indexterm index="fn" number="323" mergedindex="cp">
          <r>
            environment
          </r>
          ,
          <code>
            flushright
          </code>
        </indexterm>
      </findex>
      <findex index="fn" spaces=" ">
        <indexterm index="fn" number="324" mergedindex="cp">
          <code>
            flushright
          </code>
          <r>
            environment
          </r>
        </indexterm>
      </findex>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="354">
          ragged left text, environment for
        </indexterm>
      </cindex>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="355">
          right-justifying text, environment for
        </indexterm>
      </cindex>
      <example endspaces=" ">
        <pre xml:space="preserve">
          \begin
Default handler: &lbrace;
          flushright
Default handler: &rbrace;
          <var>
            line1
          </var>
           \\
          <var>
            line2
          </var>
           \\ ... \end
Default handler: &lbrace;
          flushright
Default handler: &rbrace;
        </pre>
      </example>
      <findex index="fn" spaces=" ">
        <indexterm index="fn" number="325" mergedindex="cp">
          \\
          <r>
            (for
            <code>
              flushright
            </code>
            )
          </r>
        </indexterm>
      </findex>
      <para>
        An environment that creates a paragraph whose lines are flush to the right-hand margin and ragged left. If you have lines that are too long to fit the margins then
Default handler: &latex;
         will linebreak them in a way that avoids hyphenation and stretching or shrinking inter-word spaces. To force a new line use a double backslash,
        <code>
          \\
        </code>
        . For the declaration form see
Default handler: &nbsp;
        <ref label="_005craggedleft">
          <xrefnodename>
            \raggedleft
          </xrefnodename>
        </ref>
        .
      </para>
      <para>
        For an example related to this environment, see
Default handler: &nbsp;
        <ref label="flushleft">
          <xrefnodename>
            flushleft
          </xrefnodename>
        </ref>
        , where one just have mutatis mutandis to replace
        <code>
          flushleft
        </code>
         by
        <code>
          flushright
        </code>
        .
      </para>
      <menu endspaces=" ">
        <menuentry>
          <menuleadingtext>
            *
          </menuleadingtext>
          <menunode>
            \raggedleft
          </menunode>
          <menuseparator>
            ::
          </menuseparator>
          <menudescription>
            <pre xml:space="preserve">
              Declaration form of the
              <code>
                flushright
              </code>
               environment.
            </pre>
          </menudescription>
        </menuentry>
      </menu>
      <node name="_005craggedleft" spaces=" ">
        <nodename>
          \raggedleft
        </nodename>
        <nodeup automatic="on">
          flushright
        </nodeup>
      </node>
      <subsection spaces=" ">
        <sectiontitle>
          <code>
            \raggedleft
          </code>
        </sectiontitle>
        <findex index="fn" spaces=" ">
          <indexterm index="fn" number="326" mergedindex="cp">
            \raggedleft
          </indexterm>
        </findex>
        <cindex index="cp" spaces=" ">
          <indexterm index="cp" number="356">
            ragged left text
          </indexterm>
        </cindex>
        <cindex index="cp" spaces=" ">
          <indexterm index="cp" number="357">
            justification, ragged left
          </indexterm>
        </cindex>
        <cindex index="cp" spaces=" ">
          <indexterm index="cp" number="358">
            right-justifying text
          </indexterm>
        </cindex>
        <para>
          Synopses:
        </para>
        <example endspaces=" ">
          <pre xml:space="preserve"Default handler: &lbrace;
>
            \raggedleft ...
Default handler: &rbrace;
          </pre>
        </example>
        <noindent/>
        <para>
          or
        </para>
        <example endspaces=" ">
          <pre xml:space="preserve">
            \begin
Default handler: &lbrace;
            <var>
              environment
            </var>
Default handler: &rbrace;
             \raggedleft ... \end
Default handler: &lbrace;
            <var>
              environment
            </var>
Default handler: &rbrace;
          </pre>
        </example>
        <para>
          A declaration which causes lines to be flush to the right margin and ragged left. It can be used inside an
          <var>
            environment
          </var>
           such as
          <code>
            quote
          </code>
           or in a
          <code>
            parbox
          </code>
          . For the environment form see
Default handler: &nbsp;
          <ref label="flushright">
            <xrefnodename>
              flushright
            </xrefnodename>
          </ref>
          .
        </para>
        <para>
          Unlike the
          <code>
            flushright
          </code>
           environment, the
          <code>
            \raggedleft
          </code>
           command does not start a new paragraph; it only changes how
Default handler: &latex;
           formats paragraph units. To affect a paragraph unit
Default handler: &textrsquo;
          s formatting, the scope of the declaration must contain the blank line or
          <code>
            \end
          </code>
           command that ends the paragraph unit.
        </para>
        <para>
          <xref label="_005craggedright">
            <xrefnodename>
              \raggedright
            </xrefnodename>
          </xref>
          , for an example related to this environment; just replace
          <code>
            \raggedright
          </code>
           there by
          <code>
            \raggedleft
          </code>
          .
        </para>
      </subsection>
    </section>
    <node name="itemize" spaces=" ">
      <nodename>
        itemize
      </nodename>
      <nodenext automatic="on">
        letter
      </nodenext>
      <nodeprev automatic="on">
        flushright
      </nodeprev>
      <nodeup automatic="on">
        Environments
      </nodeup>
    </node>
    <section spaces=" ">
      <sectiontitle>
        <code>
          itemize
        </code>
      </sectiontitle>
      <findex index="fn" spaces=" ">
        <indexterm index="fn" number="327" mergedindex="cp">
          <r>
            environment
          </r>
          ,
          <code>
            itemize
          </code>
        </indexterm>
      </findex>
      <findex index="fn" spaces=" ">
        <indexterm index="fn" number="328" mergedindex="cp">
          <code>
            itemize
          </code>
          <r>
            environment
          </r>
        </indexterm>
      </findex>
      <findex index="fn" spaces=" ">
        <indexterm index="fn" number="329" mergedindex="cp">
          \item
        </indexterm>
      </findex>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="359">
          lists of items
        </indexterm>
      </cindex>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="360">
          unordered lists
        </indexterm>
      </cindex>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="361">
          bulleted lists
        </indexterm>
      </cindex>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="362">
          bullet lists
        </indexterm>
      </cindex>
      <para>
        Synopsis:
      </para>
      <example endspaces=" ">
        <pre xml:space="preserve">
          \begin
Default handler: &lbrace;
          itemize
Default handler: &rbrace;
           \item[
          <var>
            optional label of first item
          </var>
          ]
          <var>
            text of first item
          </var>
           \item[
          <var>
            optional label of second item
          </var>
          ]
          <var>
            text of second item
          </var>
           ... \end
Default handler: &lbrace;
          itemize
Default handler: &rbrace;
        </pre>
      </example>
      <para>
        Produce an
        <dfn>
          unordered list
        </dfn>
        , sometimes called a bullet list. There must be at least one
        <code>
          \item
        </code>
         within the environment; having none causes the
Default handler: &latex;
         error
        <samp>
          Something's wrong--perhaps a missing \item
        </samp>
        .
      </para>
      <para>
        This gives a two-item list.
      </para>
      <example endspaces=" ">
        <pre xml:space="preserve">
          \begin
Default handler: &lbrace;
          itemize
Default handler: &rbrace;
           \item Pencil and watercolor sketch by Cassandra \item Rice portrait \end
Default handler: &lbrace;
          itemize
Default handler: &rbrace;
        </pre>
      </example>
      <noindent/>
      <para>
        With the default locale
Default handler: &textmdash;
        without loading e.g.
Default handler: &noeos;
        <code>
          babel
        </code>
         package with another language than USenglish
Default handler: &textmdash;
        as a top-level list each label would come out as a bullet,
Default handler: &bullet;
        . The format of the labeling depends on the nesting level; see below.
      </para>
      <findex index="fn" spaces=" ">
        <indexterm index="fn" number="330" mergedindex="cp">
          \item
        </indexterm>
      </findex>
      <para>
        Start list items with the
        <code>
          \item
        </code>
         command (
        <pxref label="_005citem">
          <xrefnodename>
            \item
          </xrefnodename>
        </pxref>
        ). If you give
        <code>
          \item
        </code>
         an optional argument by following it with square brackets, as in
        <code>
          \item[
          <var>
            Optional label
          </var>
          ]
        </code>
        , then by default
        <var>
          Optional label
        </var>
         will appear in bold and be flush right, so it could extend into the left margin. For labels that are flush left see the
        <ref label="description">
          <xrefnodename>
            description
          </xrefnodename>
        </ref>
         environment. Following the
        <code>
          \item
        </code>
         is the text of the item, which may be empty or contain multiple paragraphs.
      </para>
      <para>
        Unordered lists can be nested within one another, up to four levels deep. They can also be nested within other paragraph-making environments, such as
        <code>
          enumerate
        </code>
         (
        <pxref label="enumerate">
          <xrefnodename>
            enumerate
          </xrefnodename>
        </pxref>
        ).
      </para>
      <findex index="fn" spaces=" ">
        <indexterm index="fn" number="331" mergedindex="cp">
          \labelitemi
        </indexterm>
      </findex>
      <findex index="fn" spaces=" ">
        <indexterm index="fn" number="332" mergedindex="cp">
          \labelitemii
        </indexterm>
      </findex>
      <findex index="fn" spaces=" ">
        <indexterm index="fn" number="333" mergedindex="cp">
          \labelitemiii
        </indexterm>
      </findex>
      <findex index="fn" spaces=" ">
        <indexterm index="fn" number="334" mergedindex="cp">
          \labelitemiv
        </indexterm>
      </findex>
      <anchor name="itemize-labelitemi">
        itemize labelitemi
      </anchor>
      <anchor name="itemize-labelitemii">
        itemize labelitemii
      </anchor>
      <anchor name="itemize-labelitemiii">
        itemize labelitemiii
      </anchor>
      <anchor name="itemize-labelitemiv">
        itemize labelitemiv
      </anchor>
      <para>
        The
        <code>
          itemize
        </code>
         environment uses the commands
        <code>
          \labelitemi
        </code>
         through
        <code>
          \labelitemiv
        </code>
         to produce the default label (note the convention of lowercase roman numerals at the end of the command names that signify the nesting level). These are the default marks at each level.
      </para>
      <enumerate first="1" endspaces=" ">
        <listitem>
          <paraDefault handler: &bullet;
>
             (bullet, from
            <code>
              \textbullet
            </code>
            )
          </para>
        </listitem>
        <listitem>
          <para>
            <b>
              -
              <w>
                -
              </w>
            </b>
             (bold en-dash, from
            <code>
              \normalfont\bfseries\textendash
            </code>
            )
          </para>
        </listitem>
        <listitem>
          <para>
            * (asterisk, from
            <code>
              \textasteriskcentered
            </code>
            )
          </para>
        </listitem>
        <listitem>
          <para>
            . (vertically centered dot, rendered here as a period, from
            <code>
              \textperiodcentered
            </code>
            )
          </para>
        </listitem>
      </enumerate>
      <para>
        Change the labels with
        <code>
          \renewcommand
        </code>
        . For instance, this makes the first level use diamonds.
      </para>
      <example endspaces=" ">
        <pre xml:space="preserve">
          \renewcommand
Default handler: &lbrace;
          \labelitemi
Default handler: &rbrace;
Default handler: &lbrace;
          $\diamond$
Default handler: &rbrace;
        </pre>
      </example>
      <findex index="fn" spaces=" ">
        <indexterm index="fn" number="335" mergedindex="cp">
          \leftmargin
        </indexterm>
      </findex>
      <findex index="fn" spaces=" ">
        <indexterm index="fn" number="336" mergedindex="cp">
          \leftmargini
        </indexterm>
      </findex>
      <findex index="fn" spaces=" ">
        <indexterm index="fn" number="337" mergedindex="cp">
          \leftmarginii
        </indexterm>
      </findex>
      <findex index="fn" spaces=" ">
        <indexterm index="fn" number="338" mergedindex="cp">
          \leftmarginiii
        </indexterm>
      </findex>
      <findex index="fn" spaces=" ">
        <indexterm index="fn" number="339" mergedindex="cp">
          \leftmarginiv
        </indexterm>
      </findex>
      <findex index="fn" spaces=" ">
        <indexterm index="fn" number="340" mergedindex="cp">
          \leftmarginv
        </indexterm>
      </findex>
      <findex index="fn" spaces=" ">
        <indexterm index="fn" number="341" mergedindex="cp">
          \leftmarginvi
        </indexterm>
      </findex>
      <anchor name="itemize-leftmargin">
        itemize leftmargin
      </anchor>
      <anchor name="itemize-leftmargini">
        itemize leftmargini
      </anchor>
      <anchor name="itemize-leftmarginii">
        itemize leftmarginii
      </anchor>
      <anchor name="itemize-leftmarginiii">
        itemize leftmarginiii
      </anchor>
      <anchor name="itemize-leftmarginiv">
        itemize leftmarginiv
      </anchor>
      <anchor name="itemize-leftmarginv">
        itemize leftmarginv
      </anchor>
      <anchor name="itemize-leftmarginvi">
        itemize leftmarginvi
      </anchor>
      <para>
        The distance between the left margin of the enclosing environment and the left margin of the
        <code>
          itemize
        </code>
         list is determined by the parameters
        <code>
          \leftmargini
        </code>
         through
        <code>
          \leftmarginvi
        </code>
        . (This also uses the convention of using lowercase roman numerals a the end of the command name to denote the nesting level.) The defaults are:
        <code>
          2.5em
        </code>
         in level 1 (
        <code>
          2em
        </code>
         in two-column mode),
        <code>
          2.2em
        </code>
         in level 2,
        <code>
          1.87em
        </code>
         in level 3, and
        <code>
          1.7em
        </code>
         in level 4, with smaller values for more deeply nested levels.
      </para>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="363">
          <r>
            package
          </r>
          ,
          <code>
            enumitem
          </code>
        </indexterm>
      </cindex>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="364">
          <code>
            enumitem
          </code>
          <r>
            package
          </r>
        </indexterm>
      </cindex>
      <para>
        For other major
Default handler: &latex;
         labeled list environments, see
        <ref label="description">
          <xrefnodename>
            description
          </xrefnodename>
        </ref>
         and
        <ref label="enumerate">
          <xrefnodename>
            enumerate
          </xrefnodename>
        </ref>
        . The
        <code>
          itemize
        </code>
        ,
        <code>
          enumerate
        </code>
         and
        <code>
          description
        </code>
         environment use the same list layout parameters. For a description, including the default values, and for information about customizing list layout, see
        <ref label="list">
          <xrefnodename>
            list
          </xrefnodename>
        </ref>
        . The package
        <code>
          enumitem
        </code>
         is useful for customizing lists.
      </para>
      <para>
        This example greatly reduces the margin space for outermost itemized lists.
      </para>
      <example endspaces=" ">
        <pre xml:space="preserve">
          \setlength
Default handler: &lbrace;
          \leftmargini
Default handler: &rbrace;
Default handler: &lbrace;
          1.25em
Default handler: &rbrace;
           % default 2.5em
        </pre>
      </example>
      <findex index="fn" spaces=" ">
        <indexterm index="fn" number="342" mergedindex="cp">
          \parskip
          <r>
            example
          </r>
        </indexterm>
      </findex>
      <para>
        Especially for lists with short items, it may be desirable to elide space between items. Here is an example defining an
        <code>
          itemize*
        </code>
         environment with no extra spacing between items, or between paragraphs within a single item (
        <code>
          \parskip
        </code>
         is not list-specific,
        <pxref label="_005cparindent-_0026-_005cparskip">
          <xrefnodename>
            \parindent
            &
             \parskip
          </xrefnodename>
        </pxref>
        ):
      </para>
      <example endspaces=" ">
        <pre xml:space="preserve">
          \newenvironment
Default handler: &lbrace;
          itemize*
Default handler: &rbrace;
          %
Default handler: &lbrace;
          \begin
Default handler: &lbrace;
          itemize
Default handler: &rbrace;
          % \setlength
Default handler: &lbrace;
          \itemsep
Default handler: &rbrace;
Default handler: &lbrace;
          0pt
Default handler: &rbrace;
          % \setlength
Default handler: &lbrace;
          \parsep
Default handler: &rbrace;
Default handler: &lbrace;
          0pt
Default handler: &rbrace;
          % \setlength
Default handler: &lbrace;
          \parskip
Default handler: &rbrace;
Default handler: &lbrace;
          0pt
Default handler: &rbrace;
          %
Default handler: &rbrace;
          %
Default handler: &lbrace;
          \end
Default handler: &lbrace;
          itemize
Default handler: &rbrace;
Default handler: &rbrace;
        </pre>
      </example>
    </section>
    <node name="letter" spaces=" ">
      <nodename>
        letter
      </nodename>
      <nodenext automatic="on">
        list
      </nodenext>
      <nodeprev automatic="on">
        itemize
      </nodeprev>
      <nodeup automatic="on">
        Environments
      </nodeup>
    </node>
    <section spaces=" ">
      <sectiontitle>
        <code>
          letter
        </code>
         environment: writing letters
      </sectiontitle>
      <findex index="fn" spaces=" ">
        <indexterm index="fn" number="343" mergedindex="cp">
          <r>
            environment
          </r>
          ,
          <code>
            letter
          </code>
        </indexterm>
      </findex>
      <findex index="fn" spaces=" ">
        <indexterm index="fn" number="344" mergedindex="cp">
          <code>
            letter
          </code>
          <r>
            environment
          </r>
        </indexterm>
      </findex>
      <para>
        This environment is used for creating letters.
        <xref label="Letters">
          <xrefnodename>
            Letters
          </xrefnodename>
        </xref>
        .
      </para>
    </section>
    <node name="list" spaces=" ">
      <nodename>
        list
      </nodename>
      <nodenext automatic="on">
        math
      </nodenext>
      <nodeprev automatic="on">
        letter
      </nodeprev>
      <nodeup automatic="on">
        Environments
      </nodeup>
    </node>
    <section spaces=" ">
      <sectiontitle>
        <code>
          list
        </code>
      </sectiontitle>
      <findex index="fn" spaces=" ">
        <indexterm index="fn" number="345" mergedindex="cp">
          <r>
            environment
          </r>
          ,
          <code>
            list
          </code>
        </indexterm>
      </findex>
      <findex index="fn" spaces=" ">
        <indexterm index="fn" number="346" mergedindex="cp">
          <code>
            list
          </code>
          <r>
            environment
          </r>
        </indexterm>
      </findex>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="365">
          lists of items, generic
        </indexterm>
      </cindex>
      <para>
        Synopsis:
      </para>
      <example endspaces=" ">
        <pre xml:space="preserve">
          \begin
Default handler: &lbrace;
          list
Default handler: &rbrace;
Default handler: &lbrace;
          <var>
            labeling
          </var>
Default handler: &rbrace;
Default handler: &lbrace;
          <var>
            spacing
          </var>
Default handler: &rbrace;
           \item[
          <var>
            optional label of first item
          </var>
          ]
          <var>
            text of first item
          </var>
           \item[
          <var>
            optional label of second item
          </var>
          ]
          <var>
            text of second item
          </var>
           ... \end
Default handler: &lbrace;
          list
Default handler: &rbrace;
        </pre>
      </example>
      <para>
        An environment for constructing lists.
      </para>
      <para>
        Note that this environment does not typically appear in the document body. Most lists created by
Default handler: &latex;
         authors are the ones that come standard: the
        <code>
          description
        </code>
        ,
        <code>
          enumerate
        </code>
        , and
        <code>
          itemize
        </code>
         environments (
        <pxref label="description">
          <xrefnodename>
            description
          </xrefnodename>
        </pxref>
        ,
        <ref label="enumerate">
          <xrefnodename>
            enumerate
          </xrefnodename>
        </ref>
        , and
        <ref label="itemize">
          <xrefnodename>
            itemize
          </xrefnodename>
        </ref>
        ).
      </para>
      <para>
        Instead, the
        <code>
          list
        </code>
         environment is most often used in macros. For example, many standard
Default handler: &latex;
         environments that do not immediately appear to be lists are in fact constructed using
        <code>
          list
        </code>
        , including
        <code>
          quotation
        </code>
        ,
        <code>
          quote
        </code>
        , and
        <code>
          center
        </code>
         (
        <pxref label="quotation-_0026-quote">
          <xrefnodename>
            quotation
            &
             quote
          </xrefnodename>
        </pxref>
        ,
        <pxref label="center">
          <xrefnodename>
            center
          </xrefnodename>
        </pxref>
        ).
      </para>
      <para>
        This uses the
        <code>
          list
        </code>
         environment to define a new custom environment.
      </para>
      <example endspaces=" ">
        <pre xml:space="preserve">
          \newcounter
Default handler: &lbrace;
          namedlistcounter
Default handler: &rbrace;
           % number the items \newenvironment
Default handler: &lbrace;
          named
Default handler: &rbrace;
Default handler: &lbrace;
          \begin
Default handler: &lbrace;
          list
Default handler: &rbrace;
Default handler: &lbrace;
          Item~\Roman
Default handler: &lbrace;
          namedlistcounter
Default handler: &rbrace;
          .
Default handler: &rbrace;
           % labeling
Default handler: &lbrace;
          \usecounter
Default handler: &lbrace;
          namedlistcounter
Default handler: &rbrace;
           % set counter \setlength
Default handler: &lbrace;
          \leftmargin
Default handler: &rbrace;
Default handler: &lbrace;
          3.5em
Default handler: &rbrace;
Default handler: &rbrace;
           % set spacing
Default handler: &rbrace;
Default handler: &lbrace;
          \end
Default handler: &lbrace;
          list
Default handler: &rbrace;
Default handler: &rbrace;
           \begin
Default handler: &lbrace;
          named
Default handler: &rbrace;
           \item Shows as ``Item~I.'' \item[Special label.] Shows as ``Special label.'' \item Shows as ``Item~II.'' \end
Default handler: &lbrace;
          named
Default handler: &rbrace;
        </pre>
      </example>
      <para>
        The mandatory first argument
        <var>
          labeling
        </var>
         specifies the default labeling of list items. It can contain text and
Default handler: &latex;
         commands, as above where it contains both
        <samp>
          Item
        </samp>
         and
        <samp>
          \Roman
Default handler: &lbrace;
Default handler: &dots;
Default handler: &rbrace;
        </samp>
        .
Default handler: &latex;
         forms the label by putting the
        <var>
          labeling
        </var>
         argument in a box of width
        <code>
          \labelwidth
        </code>
        . If the label is wider than that, the additional material extends to the right. When making an instance of a
        <code>
          list
        </code>
         you can override the default labeling by giving
        <code>
          \item
        </code>
         an optional argument by including square braces and the text, as in the above
        <code>
          \item[Special label.]
        </code>
        ;
        <pxref label="_005citem">
          <xrefnodename>
            \item
          </xrefnodename>
        </pxref>
        .
      </para>
      <para>
        The mandatory second argument
        <var>
          spacing
        </var>
         has a list of commands. This list can be empty. A command that can go in here is
        <code>
          \usecounter
Default handler: &lbrace;
          <var>
            countername
          </var>
Default handler: &rbrace;
        </code>
         (
        <pxref label="_005cusecounter">
          <xrefnodename>
            \usecounter
          </xrefnodename>
        </pxref>
        ). Use this to tell
Default handler: &latex;
         to number the items using the given counter. The counter will be reset to zero each time
Default handler: &latex;
         enters the environment, and the counter is incremented by one each time
Default handler: &latex;
         encounters an
        <code>
          \item
        </code>
         that does not have an optional argument.
      </para>
      <findex index="fn" spaces=" ">
        <indexterm index="fn" number="347" mergedindex="cp">
          \makelabel
        </indexterm>
      </findex>
      <anchor name="list-makelabel">
        list makelabel
      </anchor>
      <para>
        Another command that can go in
        <var>
          spacing
        </var>
         is
        <code>
          \makelabel
        </code>
        , which constructs the label box. By default it puts the contents flush right. Its only argument is the label, which it typesets in LR mode (
        <pxref label="Modes">
          <xrefnodename>
            Modes
          </xrefnodename>
        </pxref>
        ). One example of changing its definition is that to the above
        <code>
          named
        </code>
         example, before the definition of the environment add
        <code>
          \newcommand
Default handler: &lbrace;
          \namedmakelabel
Default handler: &rbrace;
          [1]
Default handler: &lbrace;
          \textsc
Default handler: &lbrace;
          #1
Default handler: &rbrace;
Default handler: &rbrace;
        </code>
        , and between the
        <code>
          \setlength
        </code>
         command and the parenthesis that closes the
        <var>
          spacing
        </var>
         argument also add
        <code>
          \let\makelabel\namedmakelabel
        </code>
        . Then the labels will be typeset in small caps. Similarly, changing the second code line to
        <code>
          \let\makelabel\fbox
        </code>
         puts the labels inside a framed box. Another example of the
        <code>
          \makelabel
        </code>
         command is below, in the definition of the
        <code>
          redlabel
        </code>
         environment.
      </para>
      <para>
        Also often in
        <var>
          spacing
        </var>
         are commands to redefine the spacing for the list. Below are the spacing parameters with their default values. (Default values for derived environments such as
        <code>
          itemize
        </code>
         can be different than the values shown here.) See also the figure that follows the list. Each is a length (
        <pxref label="Lengths">
          <xrefnodename>
            Lengths
          </xrefnodename>
        </pxref>
        ). The vertical spaces are normally rubber lengths, with
        <code>
          plus
        </code>
         and
        <code>
          minus
        </code>
         components, to give
Default handler: &tex;
         flexibility in setting the page. Change each with a command such as
        <code>
          \setlength
Default handler: &lbrace;
          \itemsep
Default handler: &rbrace;
Default handler: &lbrace;
          2pt plus1pt minus1pt
Default handler: &rbrace;
        </code>
        . For some effects these lengths should be zero or negative.
      </para>
      <ftable commandarg="code" spaces=" " endspaces=" ">
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                <indexterm index="fn" number="348" mergedindex="cp">
                  \itemindent
                </indexterm>
                \itemindent
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <anchor name="list-itemindent">
              list itemindent
            </anchor>
            <para>
              Extra horizontal space indentation, beyond
              <code>
                leftmargin
              </code>
              , of the first line each item. Its default value is
              <code>
                0pt
              </code>
              .
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                <indexterm index="fn" number="349" mergedindex="cp">
                  \itemsep
                </indexterm>
                \itemsep
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <anchor name="list-itemsep">
              list itemsep
            </anchor>
            <para>
              Vertical space between items, beyond the
              <code>
                \parsep
              </code>
              . The defaults for the first three levels in
Default handler: &latex;
Default handler: &textrsquo;
              s
              <samp>
                article
              </samp>
              ,
              <samp>
                book
              </samp>
              , and
              <samp>
                report
              </samp>
               classes at 10 point size are:
              <code>
                4pt plus2pt minus1pt
              </code>
              ,
              <code>
                \parsep
              </code>
               (that is,
              <code>
                2pt plus1pt minus1pt
              </code>
              ), and
              <code>
                \topsep
              </code>
               (that is,
              <code>
                2pt plus1pt minus1pt
              </code>
              ). The defaults at 11 point are:
              <code>
                4.5pt plus2pt minus1pt
              </code>
              ,
              <code>
                \parsep
              </code>
               (that is,
              <code>
                2pt plus1pt minus1pt
              </code>
              ), and
              <code>
                \topsep
              </code>
               (that is,
              <code>
                2pt plus1pt minus1pt
              </code>
              ). The defaults at 12 point are:
              <code>
                5pt plus2.5pt minus1pt
              </code>
              ,
              <code>
                \parsep
              </code>
               (that is,
              <code>
                2.5pt plus1pt minus1pt
              </code>
              ), and
              <code>
                \topsep
              </code>
               (that is,
              <code>
                2.5pt plus1pt minus1pt
              </code>
              ).
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                <indexterm index="fn" number="350" mergedindex="cp">
                  \labelsep
                </indexterm>
                \labelsep
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <anchor name="list-labelsep">
              list labelsep
            </anchor>
            <para>
              Horizontal space between the label and text of an item. The default for
Default handler: &latex;
Default handler: &textrsquo;
              s
              <samp>
                article
              </samp>
              ,
              <samp>
                book
              </samp>
              , and
              <samp>
                report
              </samp>
               classes is
              <code>
                0.5em
              </code>
              .
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                <indexterm index="fn" number="351" mergedindex="cp">
                  \labelwidth
                </indexterm>
                \labelwidth
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <anchor name="list-labelwidth">
              list labelwidth
            </anchor>
            <para>
              Horizontal width. The box containing the label is nominally this wide. If
              <code>
                \makelabel
              </code>
               returns text that is wider than this then the first line of the item will be indented to make room for this extra material. If
              <code>
                \makelabel
              </code>
               returns text of width less than or equal to
              <code>
                \labelwidth
              </code>
               then
Default handler: &latex;
Default handler: &textrsquo;
              s default is that the label is typeset flush right in a box of this width.
            </para>
            <para>
              The left edge of the label box is
              <code>
                \leftmargin
              </code>
              +
              <code>
                \itemindent
              </code>
              -
              <code>
                \labelsep
              </code>
              -
              <code>
                \labelwidth
              </code>
               from the left margin of the enclosing environment.
            </para>
            <para>
              The default for
Default handler: &latex;
Default handler: &textrsquo;
              s
              <samp>
                article
              </samp>
              ,
              <samp>
                book
              </samp>
              , and
              <samp>
                report
              </samp>
               classes at the top level is
              <code>
                \leftmargini
              </code>
              -
              <code>
                \labelsep
              </code>
              , (which is
              <code>
                2em
              </code>
               in one column mode and
              <code>
                1.5em
              </code>
               in two column mode). At the second level it is
              <code>
                \leftmarginii
              </code>
              -
              <code>
                \labelsep
              </code>
              , and at the third level it is
              <code>
                \leftmarginiii
              </code>
              -
              <code>
                \labelsep
              </code>
              . These definitions make the label
Default handler: &textrsquo;
              s left edge coincide with the left margin of the enclosing environment.
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                <indexterm index="fn" number="352" mergedindex="cp">
                  \leftmargin
                </indexterm>
                \leftmargin
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <anchor name="list-leftmargin">
              list leftmargin
            </anchor>
            <para>
              Horizontal space between the left margin of the enclosing environment (or the left margin of the page if this is a top-level list), and the left margin of this list. It must be non-negative.
            </para>
            <para>
              In the standard
Default handler: &latex;
               document classes, a top-level list has this set to the value of
              <code>
                \leftmargini
              </code>
              , while a list that is nested inside a top-level list has this margin set to
              <code>
                \leftmarginii
              </code>
              . More deeply nested lists get the values of
              <code>
                \leftmarginiii
              </code>
               through
              <code>
                \leftmarginvi
              </code>
              . (Nesting greater than level five generates the error message
              <samp>
                Too deeply nested
              </samp>
              .)
            </para>
            <para>
              The defaults for the first three levels in
Default handler: &latex;
Default handler: &textrsquo;
              s
              <samp>
                article
              </samp>
              ,
              <samp>
                book
              </samp>
              , and
              <samp>
                report
              </samp>
               classes are:
              <code>
                \leftmargini
              </code>
               is
              <code>
                2.5em
              </code>
               (in two column mode,
              <code>
                2em
              </code>
              ),
              <code>
                \leftmarginii
              </code>
               is
              <code>
                2.2em
              </code>
              , and
              <code>
                \leftmarginiii
              </code>
               is
              <code>
                1.87em
              </code>
              .
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                <indexterm index="fn" number="353" mergedindex="cp">
                  \listparindent
                </indexterm>
                \listparindent
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <anchor name="list-listparindent">
              list listparindent
            </anchor>
            <para>
              Horizontal space of additional line indentation, beyond
              <code>
                \leftmargin
              </code>
              , for second and subsequent paragraphs within a list item. A negative value makes this an
Default handler: &textldquo;
              outdent
Default handler: &textrdquo;
              . Its default value is
              <code>
                0pt
              </code>
              .
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                <indexterm index="fn" number="354" mergedindex="cp">
                  \parsep
                </indexterm>
                \parsep
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <anchor name="list-parsep">
              list parsep
            </anchor>
            <para>
              Vertical space between paragraphs within an item. The defaults for the first three levels in
Default handler: &latex;
Default handler: &textrsquo;
              s
              <samp>
                article
              </samp>
              ,
              <samp>
                book
              </samp>
              , and
              <samp>
                report
              </samp>
               classes at 10 point size are:
              <code>
                4pt plus2pt minus1pt
              </code>
              ,
              <code>
                2pt plus1pt minus1pt
              </code>
              , and
              <code>
                0pt
              </code>
              . The defaults at 11 point size are:
              <code>
                4.5pt plus2pt minus1pt
              </code>
              ,
              <code>
                2pt plus1pt minus1pt
              </code>
              , and
              <code>
                0pt
              </code>
              . The defaults at 12 point size are:
              <code>
                5pt plus2.5pt minus1pt
              </code>
              ,
              <code>
                2.5pt plus1pt minus1pt
              </code>
              , and
              <code>
                0pt
              </code>
              .
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                <indexterm index="fn" number="355" mergedindex="cp">
                  \partopsep
                </indexterm>
                \partopsep
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <anchor name="list-partopsep">
              list partopsep
            </anchor>
            <para>
              Vertical space added, beyond
              <code>
                \topsep
              </code>
              +
              <code>
                \parskip
              </code>
              , to the top and bottom of the entire environment if the list instance is preceded by a blank line. (A blank line in the
Default handler: &latex;
               source before the list changes spacing at both the top and bottom of the list; whether the line following the list is blank does not matter.)
            </para>
            <para>
              The defaults for the first three levels in
Default handler: &latex;
Default handler: &textrsquo;
              s
              <samp>
                article
              </samp>
              ,
              <samp>
                book
              </samp>
              , and
              <samp>
                report
              </samp>
               classes at 10 point size are:
              <code>
                2pt plus1 minus1pt
              </code>
              ,
              <code>
                2pt plus1pt minus1pt
              </code>
              , and
              <code>
                1pt plus0pt minus1pt
              </code>
              . The defaults at 11 point are:
              <code>
                3pt plus1pt minus1pt
              </code>
              ,
              <code>
                3pt plus1pt minus1pt
              </code>
              , and
              <code>
                1pt plus0pt minus1pt
              </code>
              ). The defaults at 12 point are:
              <code>
                3pt plus2pt minus3pt
              </code>
              ,
              <code>
                3pt plus2pt minus2pt
              </code>
              , and
              <code>
                1pt plus0pt minus1pt
              </code>
              .
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                <indexterm index="fn" number="356" mergedindex="cp">
                  \rightmargin
                </indexterm>
                \rightmargin
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <anchor name="list-rightmargin">
              list rightmargin
            </anchor>
            <para>
              Horizontal space between the right margin of the list and the right margin of the enclosing environment. Its default value is
              <code>
                0pt
              </code>
              . It must be non-negative.
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                <indexterm index="fn" number="357" mergedindex="cp">
                  \topsep
                </indexterm>
                \topsep
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <anchor name="list-topsep">
              list topsep
            </anchor>
            <para>
              Vertical space added to both the top and bottom of the list, in addition to
              <code>
                \parskip
              </code>
               (
              <pxref label="_005cparindent-_0026-_005cparskip">
                <xrefnodename>
                  \parindent
                  &
                   \parskip
                </xrefnodename>
              </pxref>
              ). The defaults for the first three levels in
Default handler: &latex;
Default handler: &textrsquo;
              s
              <samp>
                article
              </samp>
              ,
              <samp>
                book
              </samp>
              , and
              <samp>
                report
              </samp>
               classes at 10 point size are:
              <code>
                8pt plus2pt minus4pt
              </code>
              ,
              <code>
                4pt plus2pt minus1pt
              </code>
              , and
              <code>
                2pt plus1pt minus1pt
              </code>
              . The defaults at 11 point are:
              <code>
                9pt plus3pt minus5pt
              </code>
              ,
              <code>
                4.5pt plus2pt minus1pt
              </code>
              , and
              <code>
                2pt plus1pt minus1pt
              </code>
              . The defaults at 12 point are:
              <code>
                10pt plus4pt minus6pt
              </code>
              ,
              <code>
                5pt plus2.5pt minus1pt
              </code>
              , and
              <code>
                2.5pt plus1pt minus1pt
              </code>
              .
            </para>
          </tableitem>
        </tableentry>
      </ftable>
      <para>
        This shows the horizontal and vertical distances.
      </para>
      <float type="" endspaces=" ">
        <image>
          <imagefile>
            latex2e-figures/list
          </imagefile>
          <imagewidth>
            3.21in
          </imagewidth>
          <imageextension>
            .png
          </imageextension>
        </image>
      </float>
      <para>
        The lengths shown are listed below. The key relationship is that the right edge of the bracket for
        <var>
          h1
        </var>
         equals the right edge of the bracket for
        <var>
          h4
        </var>
        , so that the left edge of the label box is at
        <var>
          h3
        </var>
        +
        <var>
          h4
        </var>
        -(
        <var>
          h0
        </var>
        +
        <var>
          h1
        </var>
        ).
      </para>
      <table commandarg="var" spaces=" " endspaces=" ">
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="var">
                v0
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <para>
              <math>
                <codeDefault handler: &backslash;
>
                  topsep
                </code>
                 +
                <codeDefault handler: &backslash;
>
                  parskip
                </code>
              </math>
               if the list environment does not start a new paragraph, and
              <code>
                \topsep
              </code>
              +
              <code>
                \parskip
              </code>
              +
              <code>
                \partopsep
              </code>
               if it does
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="var">
                v1
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <para>
              <code>
                \parsep
              </code>
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="var">
                v2
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <para>
              <code>
                \itemsep
              </code>
              +
              <code>
                \parsep
              </code>
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="var">
                v3
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <para>
              Same as
              <var>
                v0
              </var>
              . (This space is affected by whether a blank line appears in the source above the environment; whether a blank line appears in the source below the environment does not matter.)
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="var">
                h0
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <para>
              <code>
                \labelwidth
              </code>
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="var">
                h1
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <para>
              <code>
                \labelsep
              </code>
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="var">
                h2
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <para>
              <code>
                \listparindent
              </code>
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="var">
                h3
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <para>
              <code>
                \leftmargin
              </code>
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="var">
                h4
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <para>
              <code>
                \itemindent
              </code>
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="var">
                h5
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <para>
              <code>
                \rightmargin
              </code>
            </para>
          </tableitem>
        </tableentry>
      </table>
      <para>
        The list
Default handler: &textrsquo;
        s left and right margins, shown above as
        <var>
          h3
        </var>
         and
        <var>
          h5
        </var>
        , are with respect to the ones provided by the surrounding environment, or with respect to the page margins for a top-level list. The line width used for typesetting the list items is
        <code>
          \linewidth
        </code>
         (
        <pxref label="Page-layout-parameters">
          <xrefnodename>
            Page layout parameters
          </xrefnodename>
        </pxref>
        ). For instance, set the list
Default handler: &textrsquo;
        s left margin to be one quarter of the distance between the left and right margins of the enclosing environment with
        <code>
          \setlength
Default handler: &lbrace;
          \leftmargin
Default handler: &rbrace;
Default handler: &lbrace;
          0.25\linewidth
Default handler: &rbrace;
        </code>
        .
      </para>
      <para>
        Page breaking in a list structure is controlled by the three parameters below. For each, the
Default handler: &latex;
         default is
        <code>
          -\
Default handler: &arobase;
          lowpenalty
        </code>
        , that is,
        <code>
          -51
        </code>
        . Because it is negative, it somewhat encourages a page break at each spot. Change it with, e.g.,
        <code>
          \
Default handler: &arobase;
          beginparpenalty=9999
        </code>
        ; a value of 10000 prohibits a page break.
      </para>
      <ftable commandarg="code" spaces=" " endspaces=" ">
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                <indexterm index="fn" number="358" mergedindex="cp">
                  \
Default handler: &arobase;
                  beginparpenalty
                </indexterm>
                \
Default handler: &arobase;
                beginparpenalty
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <anchor name="list-beginparpenalty">
              list beginparpenalty
            </anchor>
            <para>
              The page breaking penalty for breaking before the list (default
              <code>
                -51
              </code>
              ).
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                <indexterm index="fn" number="359" mergedindex="cp">
                  \
Default handler: &arobase;
                  itempenalty
                </indexterm>
                \
Default handler: &arobase;
                itempenalty
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <anchor name="list-itempenalty">
              list itempenalty
            </anchor>
            <para>
              The page breaking penalty for breaking before a list item (default
              <code>
                -51
              </code>
              ).
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                <indexterm index="fn" number="360" mergedindex="cp">
                  \
Default handler: &arobase;
                  endparpenalty
                </indexterm>
                \
Default handler: &arobase;
                endparpenalty
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <anchor name="list-endparpenalty">
              list endparpenalty
            </anchor>
            <para>
              The page breaking penalty for breaking after a list (default
              <code>
                -51
              </code>
              ).
            </para>
          </tableitem>
        </tableentry>
      </ftable>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="366">
          <r>
            package
          </r>
          ,
          <code>
            enumitem
          </code>
        </indexterm>
      </cindex>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="367">
          <code>
            enumitem
          </code>
          <r>
            package
          </r>
        </indexterm>
      </cindex>
      <para>
        The package
        <code>
          enumitem
        </code>
         is useful for customizing lists.
      </para>
      <para>
        This example has the labels in red. They are numbered, and the left edge of the label lines up with the left edge of the item text.
        <xref label="_005cusecounter">
          <xrefnodename>
            \usecounter
          </xrefnodename>
        </xref>
        .
      </para>
      <example endspaces=" ">
        <pre xml:space="preserve">
          \usepackage
Default handler: &lbrace;
          color
Default handler: &rbrace;
           \newcounter
Default handler: &lbrace;
          cnt
Default handler: &rbrace;
           \newcommand
Default handler: &lbrace;
          \makeredlabel
Default handler: &rbrace;
          [1]
Default handler: &lbrace;
          \textcolor
Default handler: &lbrace;
          red
Default handler: &rbrace;
Default handler: &lbrace;
          #1.
Default handler: &rbrace;
Default handler: &rbrace;
           \newenvironment
Default handler: &lbrace;
          redlabel
Default handler: &rbrace;
Default handler: &lbrace;
          \begin
Default handler: &lbrace;
          list
Default handler: &rbrace;
Default handler: &lbrace;
          \arabic
Default handler: &lbrace;
          cnt
Default handler: &rbrace;
Default handler: &rbrace;
Default handler: &lbrace;
          \usecounter
Default handler: &lbrace;
          cnt
Default handler: &rbrace;
           \setlength
Default handler: &lbrace;
          \labelwidth
Default handler: &rbrace;
Default handler: &lbrace;
          0em
Default handler: &rbrace;
           \setlength
Default handler: &lbrace;
          \labelsep
Default handler: &rbrace;
Default handler: &lbrace;
          0.5em
Default handler: &rbrace;
           \setlength
Default handler: &lbrace;
          \leftmargin
Default handler: &rbrace;
Default handler: &lbrace;
          1.5em
Default handler: &rbrace;
           \setlength
Default handler: &lbrace;
          \itemindent
Default handler: &rbrace;
Default handler: &lbrace;
          0.5em
Default handler: &rbrace;
           % equals \labelwidth+\labelsep \let\makelabel=\makeredlabel
Default handler: &rbrace;
Default handler: &rbrace;
Default handler: &lbrace;
          \end
Default handler: &lbrace;
          list
Default handler: &rbrace;
Default handler: &rbrace;
        </pre>
      </example>
      <menu endspaces=" ">
        <menuentry>
          <menuleadingtext>
            *
          </menuleadingtext>
          <menunode>
            \item
          </menunode>
          <menuseparator>
            ::
          </menuseparator>
          <menudescription>
            <pre xml:space="preserve">
              An entry in a list.
            </pre>
          </menudescription>
        </menuentry>
        <menuentry>
          <menuleadingtext>
            *
          </menuleadingtext>
          <menunode>
            trivlist
          </menunode>
          <menuseparator>
            ::
          </menuseparator>
          <menudescription>
            <pre xml:space="preserve">
              A restricted form of
              <code>
                list
              </code>
              .
            </pre>
          </menudescription>
        </menuentry>
      </menu>
      <node name="_005citem" spaces=" ">
        <nodename>
          \item
        </nodename>
        <nodenext automatic="on">
          trivlist
        </nodenext>
        <nodeup automatic="on">
          list
        </nodeup>
      </node>
      <subsection spaces=" ">
        <sectiontitle>
          <code>
            \item
          </code>
          : An entry in a list
        </sectiontitle>
        <para>
          Synopsis:
        </para>
        <example endspaces=" ">
          <pre xml:space="preserve">
            \item text of item
          </pre>
        </example>
        <noindent/>
        <para>
          or
        </para>
        <example endspaces=" ">
          <pre xml:space="preserve">
            \item[
            <var>
              optional-label
            </var>
            ] text of item
          </pre>
        </example>
        <para>
          An entry in a list. The entries are prefixed by a label, whose default depends on the list type.
        </para>
        <para>
          Because the optional label is surrounded by square brackets
          <samp>
            [...]
          </samp>
          , if you have an item whose text starts with [, you have to hide the bracket inside curly braces, as in:
          <code>
            \item
Default handler: &lbrace;
            [
Default handler: &rbrace;
             is an open square bracket
          </code>
          ; otherwise,
Default handler: &latex;
           will think it marks the start of an optional label.
        </para>
        <para>
          Similarly, if the item does have the optional label and you need a close square bracket inside that label, you must hide it in the same way:
          <code>
            \item[Close square bracket,
Default handler: &lbrace;
            ]
Default handler: &rbrace;
            ]
          </code>
          .
          <xref label="LaTeX-command-syntax">
            <xrefnodenameDefault handler: &latex;
>
               command syntax
            </xrefnodename>
          </xref>
          .
        </para>
        <para>
          In this example the enumerate list has two items that use the default label and one that uses the optional label.
        </para>
        <example endspaces=" ">
          <pre xml:space="preserve">
            \begin
Default handler: &lbrace;
            enumerate
Default handler: &rbrace;
             \item Moe \item[sometimes] Shemp \item Larry \end
Default handler: &lbrace;
            enumerate
Default handler: &rbrace;
          </pre>
        </example>
        <para>
          The first item is labelled
          <samp>
            1.
          </samp>
          , the second item is labelled
          <samp>
            sometimes
          </samp>
          , and the third item is labelled
          <samp>
            2.
          </samp>
          . Because of the optional label in the second item, the third item is not labelled
Default handler: &nbsp;
          <samp>
            3.
          </samp>
          .
        </para>
      </subsection>
      <node name="trivlist" spaces=" ">
        <nodename>
          trivlist
        </nodename>
        <nodeprev automatic="on">
          \item
        </nodeprev>
        <nodeup automatic="on">
          list
        </nodeup>
      </node>
      <subsection spaces=" ">
        <sectiontitle>
          <code>
            trivlist
          </code>
          : A restricted form of
          <code>
            list
          </code>
        </sectiontitle>
        <para>
          Synopsis:
        </para>
        <example endspaces=" ">
          <pre xml:space="preserve">
            \begin
Default handler: &lbrace;
            trivlist
Default handler: &rbrace;
             ... \end
Default handler: &lbrace;
            trivlist
Default handler: &rbrace;
          </pre>
        </example>
        <para>
          A restricted version of the list environment, in which margins are not indented and an
          <code>
            \item
          </code>
           without an optional argument produces no text. It is most often used in macros, to define an environment where the
          <code>
            \item
          </code>
           command is part of the environment
Default handler: &textrsquo;
          s definition. For instance, the
          <code>
            center
          </code>
           environment is defined essentially like this:
        </para>
        <example endspaces=" ">
          <pre xml:space="preserve">
            \newenvironment
Default handler: &lbrace;
            center
Default handler: &rbrace;
Default handler: &lbrace;
            \begin
Default handler: &lbrace;
            trivlist
Default handler: &rbrace;
            \centering\item\relax
Default handler: &rbrace;
Default handler: &lbrace;
            \end
Default handler: &lbrace;
            trivlist
Default handler: &rbrace;
Default handler: &rbrace;
          </pre>
        </example>
        <para>
          Using
          <code>
            trivlist
          </code>
           in this way allows the macro to inherit some common code: combining vertical space of two adjacent environments; detecting whether the text following the environment should be considered a new paragraph or a continuation of the previous one; adjusting the left and right margins for possible nested list environments.
        </para>
        <para>
          Specifically,
          <code>
            trivlist
          </code>
           uses the current values of the list parameters (
          <pxref label="list">
            <xrefnodename>
              list
            </xrefnodename>
          </pxref>
          ), except that
          <code>
            \parsep
          </code>
           is set to the value of
          <code>
            \parskip
          </code>
          , and
          <code>
            \leftmargin
          </code>
          ,
          <code>
            \labelwidth
          </code>
          , and
          <code>
            \itemindent
          </code>
           are set to zero.
        </para>
        <para>
          This example outputs the items as two paragraphs, except that (by default) they have no paragraph indent and are vertically separated.
        </para>
        <example endspaces=" ">
          <pre xml:space="preserve">
            \begin
Default handler: &lbrace;
            trivlist
Default handler: &rbrace;
             \item The \textit
Default handler: &lbrace;
            Surprise
Default handler: &rbrace;
             is not old; no one would call her old. \item She has a bluff bow, lovely lines. \end
Default handler: &lbrace;
            trivlist
Default handler: &rbrace;
          </pre>
        </example>
      </subsection>
    </section>
    <node name="math" spaces=" ">
      <nodename>
        math
      </nodename>
      <nodenext automatic="on">
        minipage
      </nodenext>
      <nodeprev automatic="on">
        list
      </nodeprev>
      <nodeup automatic="on">
        Environments
      </nodeup>
    </node>
    <section spaces=" ">
      <sectiontitle>
        <code>
          math
        </code>
      </sectiontitle>
      <findex index="fn" spaces=" ">
        <indexterm index="fn" number="361" mergedindex="cp">
          <r>
            environment
          </r>
          ,
          <code>
            math
          </code>
        </indexterm>
      </findex>
      <findex index="fn" spaces=" ">
        <indexterm index="fn" number="362" mergedindex="cp">
          <code>
            math
          </code>
          <r>
            environment
          </r>
        </indexterm>
      </findex>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="368">
          inline formulas
        </indexterm>
      </cindex>
      <para>
        Synopsis:
      </para>
      <example endspaces=" ">
        <pre xml:space="preserve">
          \begin
Default handler: &lbrace;
          math
Default handler: &rbrace;
          <var>
            math
          </var>
           \end
Default handler: &lbrace;
          math
Default handler: &rbrace;
        </pre>
      </example>
      <findex index="fn" spaces=" ">
        <indexterm index="fn" number="363" mergedindex="cp">
          $
          <r>
            inline math
          </r>
        </indexterm>
      </findex>
      <findex index="fn" spaces=" ">
        <indexterm index="fn" number="364" mergedindex="cp">
          \(...\)
          <r>
            inline math
          </r>
        </indexterm>
      </findex>
      <para>
        The
        <code>
          math
        </code>
         environment inserts given
        <var>
          math
        </var>
         material within the running text.
        <code>
          \(...\)
        </code>
         and
        <code>
          $...$
        </code>
         are synonyms.
        <xref label="Math-formulas">
          <xrefnodename>
            Math formulas
          </xrefnodename>
        </xref>
        .
      </para>
    </section>
    <node name="minipage" spaces=" ">
      <nodename>
        minipage
      </nodename>
      <nodenext automatic="on">
        picture
      </nodenext>
      <nodeprev automatic="on">
        math
      </nodeprev>
      <nodeup automatic="on">
        Environments
      </nodeup>
    </node>
    <section spaces=" ">
      <sectiontitle>
        <code>
          minipage
        </code>
      </sectiontitle>
      <findex index="fn" spaces=" ">
        <indexterm index="fn" number="365" mergedindex="cp">
          <r>
            environment
          </r>
          ,
          <code>
            minipage
          </code>
        </indexterm>
      </findex>
      <findex index="fn" spaces=" ">
        <indexterm index="fn" number="366" mergedindex="cp">
          <code>
            minipage
          </code>
          <r>
            environment
          </r>
        </indexterm>
      </findex>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="369">
          minipage, creating a
        </indexterm>
      </cindex>
      <para>
        Synopses:
      </para>
      <example endspaces=" ">
        <pre xml:space="preserve">
          \begin
Default handler: &lbrace;
          minipage
Default handler: &rbrace;
Default handler: &lbrace;
          <var>
            width
          </var>
Default handler: &rbrace;
          <var>
            contents
          </var>
           \end
Default handler: &lbrace;
          minipage
Default handler: &rbrace;
        </pre>
      </example>
      <noindent/>
      <para>
        or
      </para>
      <example endspaces=" ">
        <pre xml:space="preserve">
          \begin
Default handler: &lbrace;
          minipage
Default handler: &rbrace;
          [
          <var>
            position
          </var>
          ][
          <var>
            height
          </var>
          ][
          <var>
            inner-pos
          </var>
          ]
Default handler: &lbrace;
          <var>
            width
          </var>
Default handler: &rbrace;
          <var>
            contents
          </var>
           \end
Default handler: &lbrace;
          minipage
Default handler: &rbrace;
        </pre>
      </example>
      <para>
        Put
        <var>
          contents
        </var>
         into a box that is
        <var>
          width
        </var>
         wide. This is like a small version of a page; it can contain its own footnotes, itemized lists, etc. (There are some restrictions, including that it cannot have floats.) This box will not be broken across pages. So
        <code>
          minipage
        </code>
         is similar to
        <code>
          \parbox
        </code>
         (
        <pxref label="_005cparbox">
          <xrefnodename>
            \parbox
          </xrefnodename>
        </pxref>
        ) but here you can have paragraphs.
      </para>
      <para>
        This example will be 3
Default handler: &nbsp;
        inches wide, and has two paragraphs.
      </para>
      <example endspaces=" ">
        <pre xml:space="preserve">
          \begin
Default handler: &lbrace;
          minipage
Default handler: &rbrace;
Default handler: &lbrace;
          3in
Default handler: &rbrace;
           Stephen Kleene was a founder of the Theory of Computation. He was a student of Church, wrote three influential texts, was President of the Association for Symbolic Logic, and won the National Medal of Science. \end
Default handler: &lbrace;
          minipage
Default handler: &rbrace;
        </pre>
      </example>
      <noindent/>
      <para>
        See below for a discussion of the paragraph indent inside a
        <code>
          minipage
        </code>
        .
      </para>
      <para>
        The required argument
        <var>
          width
        </var>
         is a rigid length (
        <pxref label="Lengths">
          <xrefnodename>
            Lengths
          </xrefnodename>
        </pxref>
        ). It gives the width of the box into which
        <var>
          contents
        </var>
         are typeset.
      </para>
      <para>
        There are three optional arguments,
        <var>
          position
        </var>
        ,
        <var>
          height
        </var>
        , and
        <var>
          inner-pos
        </var>
        . You need not include all three. For example, get the default
        <var>
          position
        </var>
         and set the
        <var>
          height
        </var>
         with
        <code>
          \begin
Default handler: &lbrace;
          minipage
Default handler: &rbrace;
          [c][2.54cm]
Default handler: &lbrace;
          \columnwidth
Default handler: &rbrace;
          <var>
            contents
          </var>
           \end
Default handler: &lbrace;
          minipage
Default handler: &rbrace;
        </code>
        . (Get the natural height with an empty argument,
        <code>
          []
        </code>
        .)
      </para>
      <para>
        The optional argument
        <var>
          position
        </var>
         governs how the
        <code>
          minipage
        </code>
         vertically aligns with the surrounding material.
      </para>
      <table commandarg="code" spaces=" " endspaces=" ">
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                c
              </itemformat>
            </item>
          </tableterm>
          <tableitemDefault handler: <!-- c xx Clarify what it means when adjacent text lines do not have aligned -->
Default handler: <!-- c vertical center with each other -->
>
            <para>
              (synonym
              <code>
                m
              </code>
              ) Default. Positions the
              <code>
                minipage
              </code>
               so its vertical center lines up with the center of the adjacent text line.
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                t
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <findex index="fn" spaces=" ">
              <indexterm index="fn" number="367" mergedindex="cp">
                \vtop
                <r>
                  plain
Default handler: &tex;
                </r>
              </indexterm>
            </findex>
            <para>
              Align the baseline of the top line in the
              <code>
                minipage
              </code>
               with the baseline of the surrounding text (plain
Default handler: &tex;
Default handler: &textrsquo;
              s
              <code>
                \vtop
              </code>
              ).
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                b
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <findex index="fn" spaces=" ">
              <indexterm index="fn" number="368" mergedindex="cp">
                \vbox
                <r>
                  (plain
Default handler: &tex;
                  )
                </r>
              </indexterm>
            </findex>
            <para>
              Align the baseline of the bottom line in the
              <code>
                minipage
              </code>
               with the baseline of the surrounding text (plain
Default handler: &tex;
Default handler: &textrsquo;
              s
              <code>
                \vbox
              </code>
              ).
            </para>
          </tableitem>
        </tableentry>
      </table>
      <para>
        To see the effects of these, contrast running this
      </para>
      <example endspaces=" ">
        <pre xml:space="preserve">
          ---\begin
Default handler: &lbrace;
          minipage
Default handler: &rbrace;
          [c]
Default handler: &lbrace;
          0.25in
Default handler: &rbrace;
           first\\ second\\ third \end
Default handler: &lbrace;
          minipage
Default handler: &rbrace;
        </pre>
      </example>
      <noindent/>
      <para>
        with the results of changing
        <code>
          c
        </code>
         to
        <code>
          b
        </code>
         or
Default handler: &nbsp;
        <code>
          t
        </code>
        .
      </para>
Default handler: <!-- c xx Clarify what happens if user enter a rubber length instead of a -->
Default handler: <!-- c rigid length. -->
      <para>
        The optional argument
        <var>
          height
        </var>
         is a rigid length (
        <pxref label="Lengths">
          <xrefnodename>
            Lengths
          </xrefnodename>
        </pxref>
        ). It sets the height of the
        <code>
          minipage
        </code>
        . You can enter any value larger than, or equal to, or smaller than the
        <code>
          minipage
        </code>
Default handler: &textrsquo;
        s natural height and
Default handler: &latex;
         will not give an error or warning. You can also set it to a height of zero or a negative value.
      </para>
      <para>
        The final optional argument
        <var>
          inner-pos
        </var>
         controls the placement of
        <var>
          contents
        </var>
         inside the box. These are the possible values are (the default is the value of
        <var>
          position
        </var>
        ).
      </para>
      <table commandarg="code" spaces=" " endspaces=" ">
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                t
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <para>
              Place
              <var>
                contents
              </var>
               at the top of the box.
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                c
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <para>
              Place it in the vertical center.
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                b
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <para>
              Place it at the box bottom.
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                s
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <para>
              Stretch
              <var>
                contents
              </var>
               out vertically; it must contain vertically stretchable space.
            </para>
          </tableitem>
        </tableentry>
      </table>
      <para>
        The
        <var>
          inner-pos
        </var>
         argument makes sense when the
        <var>
          height
        </var>
         option is set to a value larger than the
        <code>
          minipage
        </code>
Default handler: &textrsquo;
        s natural height. To see the effect of the options, run this example with the various choices in place of
        <code>
          b
        </code>
        .
      </para>
      <example endspaces=" ">
        <pre xml:space="preserve">
          Text before \begin
Default handler: &lbrace;
          center
Default handler: &rbrace;
           ---\begin
Default handler: &lbrace;
          minipage
Default handler: &rbrace;
          [c][3in][b]
Default handler: &lbrace;
          0.25\textwidth
Default handler: &rbrace;
           first\\ second\\ third \end
Default handler: &lbrace;
          minipage
Default handler: &rbrace;
           \end
Default handler: &lbrace;
          center
Default handler: &rbrace;
           Text after
        </pre>
      </example>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="370">
          indentation of paragraphs, in minipage
        </indexterm>
      </cindex>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="371">
          paragraph indentation, in minipage
        </indexterm>
      </cindex>
      <findex index="fn" spaces=" ">
        <indexterm index="fn" number="369" mergedindex="cp">
          \parindent
        </indexterm>
      </findex>
      <para>
        By default paragraphs are not indented in a
        <code>
          minipage
        </code>
        . Change that with a command such as
        <code>
          \setlength
Default handler: &lbrace;
          \parindent
Default handler: &rbrace;
Default handler: &lbrace;
          1pc
Default handler: &rbrace;
        </code>
         at the start of
        <var>
          contents
        </var>
        .
      </para>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="372">
          footnotes in figures
        </indexterm>
      </cindex>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="373">
          figures, footnotes in
        </indexterm>
      </cindex>
      <para>
        Footnotes in a
        <code>
          minipage
        </code>
         environment are handled in a way that is particularly useful for putting footnotes in figures or tables. A
        <code>
          \footnote
        </code>
         or
        <code>
          \footnotetext
        </code>
         command puts the footnote at the bottom of the minipage instead of at the bottom of the page, and it uses the
        <code>
          \mpfootnote
        </code>
         counter instead of the ordinary
        <code>
          footnote
        </code>
         counter (
        <pxref label="Counters">
          <xrefnodename>
            Counters
          </xrefnodename>
        </pxref>
        ).
      </para>
      <para>
        This puts the footnote at the bottom of the table, not the bottom of the page.
      </para>
      <example endspaces=" ">
        <pre xml:space="preserve">
          \begin
Default handler: &lbrace;
          center
Default handler: &rbrace;
           % center the minipage on the line \begin
Default handler: &lbrace;
          minipage
Default handler: &rbrace;
Default handler: &lbrace;
          2.5in
Default handler: &rbrace;
           \begin
Default handler: &lbrace;
          center
Default handler: &rbrace;
           % center the table inside the minipage \begin
Default handler: &lbrace;
          tabular
Default handler: &rbrace;
Default handler: &lbrace;
          ll
Default handler: &rbrace;
           \textsc
Default handler: &lbrace;
          Monarch
Default handler: &rbrace;
          &
          \textsc
Default handler: &lbrace;
          Reign
Default handler: &rbrace;
           \\ \hline Elizabeth II
          &
          63 years\footnote
Default handler: &lbrace;
          to date
Default handler: &rbrace;
           \\ Victoria
          &
          63 years \\ George III
          &
          59 years \end
Default handler: &lbrace;
          tabular
Default handler: &rbrace;
           \end
Default handler: &lbrace;
          center
Default handler: &rbrace;
           \end
Default handler: &lbrace;
          minipage
Default handler: &rbrace;
           \end
Default handler: &lbrace;
          center
Default handler: &rbrace;
        </pre>
      </example>
      <para>
        If you nest minipages then there is an oddness when using footnotes. Footnotes appear at the bottom of the text ended by the next
        <code>
          \end
Default handler: &lbrace;
          minipage
Default handler: &rbrace;
        </code>
         which may not be their logical place.
      </para>
      <para>
        This puts a table containing data side by side with a map graphic. They are vertically centered.
      </para>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="374">
          <r>
            package
          </r>
          ,
          <code>
            siunitx
          </code>
        </indexterm>
      </cindex>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="375">
          <code>
            siunitx
          </code>
          <r>
            package
          </r>
        </indexterm>
      </cindex>
      <example endspaces=" ">
        <pre xml:space="preserve">
          % siunitx to have the S column specifier, % which aligns numbers on their decimal point. \usepackage
Default handler: &lbrace;
          siunitx
Default handler: &rbrace;
           \newcommand*
Default handler: &lbrace;
          \vcenteredhbox
Default handler: &rbrace;
          [1]
Default handler: &lbrace;
          \begin
Default handler: &lbrace;
          tabular
Default handler: &rbrace;
Default handler: &lbrace;
Default handler: &arobase;
Default handler: &lbrace;
Default handler: &rbrace;
          c
Default handler: &arobase;
Default handler: &lbrace;
Default handler: &rbrace;
Default handler: &rbrace;
          #1\end
Default handler: &lbrace;
          tabular
Default handler: &rbrace;
Default handler: &rbrace;
           ... \begin
Default handler: &lbrace;
          center
Default handler: &rbrace;
           \vcenteredhbox
Default handler: &lbrace;
          \includegraphics[width=0.3\textwidth]
Default handler: &lbrace;
          nyc.png
Default handler: &rbrace;
Default handler: &rbrace;
           \hspace
Default handler: &lbrace;
          0.1\textwidth
Default handler: &rbrace;
           \begin
Default handler: &lbrace;
          minipage
Default handler: &rbrace;
Default handler: &lbrace;
          0.5\textwidth
Default handler: &rbrace;
           \begin
Default handler: &lbrace;
          tabular
Default handler: &rbrace;
Default handler: &lbrace;
          r|S
Default handler: &rbrace;
           % \multicolumn to remove vertical bar between column headers \multicolumn
Default handler: &lbrace;
          1
Default handler: &rbrace;
Default handler: &lbrace;
          r
Default handler: &rbrace;
Default handler: &lbrace;
          Borough
Default handler: &rbrace;
          &
           % braces to prevent siunitx from misinterpreting the % period as a decimal separator
Default handler: &lbrace;
          Pop. (million)
Default handler: &rbrace;
           \\ \hline The Bronx
          &
          1.5 \\ Brooklyn
          &
          2.6 \\ Manhattan
          &
          1.6 \\ Queens
          &
          2.3 \\ Staten Island
          &
          0.5 \end
Default handler: &lbrace;
          tabular
Default handler: &rbrace;
           \end
Default handler: &lbrace;
          minipage
Default handler: &rbrace;
           \end
Default handler: &lbrace;
          center
Default handler: &rbrace;
        </pre>
      </example>
    </section>
    <node name="picture" spaces=" ">
      <nodename>
        picture
      </nodename>
      <nodenext automatic="on">
        quotation
        &
         quote
      </nodenext>
      <nodeprev automatic="on">
        minipage
      </nodeprev>
      <nodeup automatic="on">
        Environments
      </nodeup>
    </node>
    <section spaces=" ">
      <sectiontitle>
        <code>
          picture
        </code>
      </sectiontitle>
      <findex index="fn" spaces=" ">
        <indexterm index="fn" number="370" mergedindex="cp">
          <r>
            environment
          </r>
          ,
          <code>
            picture
          </code>
        </indexterm>
      </findex>
      <findex index="fn" spaces=" ">
        <indexterm index="fn" number="371" mergedindex="cp">
          <code>
            picture
          </code>
          <r>
            environment
          </r>
        </indexterm>
      </findex>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="376">
          creating pictures
        </indexterm>
      </cindex>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="377">
          pictures, creating
        </indexterm>
      </cindex>
      <para>
        Synopses:
      </para>
      <example endspaces=" ">
        <pre xml:space="preserve">
          \begin
Default handler: &lbrace;
          picture
Default handler: &rbrace;
          (
          <var>
            width
          </var>
          ,
          <var>
            height
          </var>
          )
          <var>
            picture command
          </var>
           \end
Default handler: &lbrace;
          picture
Default handler: &rbrace;
        </pre>
      </example>
      <noindent/>
      <para>
        or
      </para>
      <example endspaces=" ">
        <pre xml:space="preserve">
          \begin
Default handler: &lbrace;
          picture
Default handler: &rbrace;
          (
          <var>
            width
          </var>
          ,
          <var>
            height
          </var>
          )(
          <var>
            xoffset
          </var>
          ,
          <var>
            yoffset
          </var>
          )
          <var>
            picture command
          </var>
           \end
Default handler: &lbrace;
          picture
Default handler: &rbrace;
        </pre>
      </example>
      <noindent/>
      <para>
        Where there may be any number of
        <var>
          picture command
        </var>
Default handler: &textrsquo;
        s.
      </para>
      <para>
        An environment to create simple pictures containing lines, arrows, boxes, circles, and text. This environment is not obsolete, but new documents typically use much more powerful graphics creation systems, such as TikZ, PSTricks, MetaPost, or Asymptote. None of these are covered in this document; see CTAN.
      </para>
      <para>
        To start, here
Default handler: &textrsquo;
        s an example showing the parallelogram law for adding vectors.
      </para>
      <findex index="fn" spaces=" ">
        <indexterm index="fn" number="372" mergedindex="cp">
          \unitlength
        </indexterm>
      </findex>
      <example endspaces=" ">
        <pre xml:space="preserve">
          \setlength
Default handler: &lbrace;
          \unitlength
Default handler: &rbrace;
Default handler: &lbrace;
          1cm
Default handler: &rbrace;
           \begin
Default handler: &lbrace;
          picture
Default handler: &rbrace;
          (6,6) % picture box will be 6cm wide by 6cm tall \put(0,0)
Default handler: &lbrace;
          \vector(2,1)
Default handler: &lbrace;
          4
Default handler: &rbrace;
Default handler: &rbrace;
           % for every 2 over this vector goes 1 up \put(2,1)
Default handler: &lbrace;
          \makebox(0,0)[l]
Default handler: &lbrace;
          \ first leg
Default handler: &rbrace;
Default handler: &rbrace;
           \put(4,2)
Default handler: &lbrace;
          \vector(1,2)
Default handler: &lbrace;
          2
Default handler: &rbrace;
Default handler: &rbrace;
           \put(5,4)
Default handler: &lbrace;
          \makebox(0,0)[l]
Default handler: &lbrace;
          \ second leg
Default handler: &rbrace;
Default handler: &rbrace;
           \put(0,0)
Default handler: &lbrace;
          \vector(1,1)
Default handler: &lbrace;
          6
Default handler: &rbrace;
Default handler: &rbrace;
           \put(3,3)
Default handler: &lbrace;
          \makebox(0,0)[r]
Default handler: &lbrace;
          sum\
Default handler: &rbrace;
Default handler: &rbrace;
           \end
Default handler: &lbrace;
          picture
Default handler: &rbrace;
        </pre>
      </example>
      <para>
        The
        <code>
          picture
        </code>
         environment has one required argument, a pair of positive real numbers (
        <var>
          width
        </var>
        ,
        <var>
          height
        </var>
        ). Multiply these by the value
        <code>
          \unitlength
        </code>
         to get the nominal size of the output, i.e.
Default handler: &noeos;
         the space that
Default handler: &latex;
         reserves on the output page. This nominal size need not be how large the picture really is;
Default handler: &latex;
         will draw things from the picture outside the picture
Default handler: &textrsquo;
        s box.
      </para>
      <para>
        This environment also has an optional argument (
        <var>
          xoffset
        </var>
        ,
        <var>
          yoffset
        </var>
        ). It is used to shift the origin. Unlike most optional arguments, this one is not contained in square brackets. As with the required argument, it consists of a pair of two real numbers, but these may also be negative or null. Multiply these by
        <code>
          \unitlength
        </code>
         to get the coordinates of the point at the lower-left corner of the picture.
      </para>
      <para>
        For example, if
        <code>
          \unitlength
        </code>
         has been set to
        <code>
          1mm
        </code>
        , the command
      </para>
      <example endspaces=" ">
        <pre xml:space="preserve">
          \begin
Default handler: &lbrace;
          picture
Default handler: &rbrace;
          (100,200)(10,20)
        </pre>
      </example>
      <noindent/>
      <para>
        produces a box of width 100 millimeters and height 200 millimeters. The picture
Default handler: &textrsquo;
        s origin is the point (10mm,20mm) and so the lower-left corner is there, and the upper-right corner is at (110mm,220mm). When you first draw a picture you typically omit the optional argument, leaving the origin at the lower-left corner. If you then want to modify your picture by shifting everything, you can just add the appropriate optional argument.
      </para>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="378">
          position, in picture
        </indexterm>
      </cindex>
      <para>
        Each
        <var>
          picture command
        </var>
         tells
Default handler: &latex;
         where to put something by providing its position. A
        <dfn>
          position
        </dfn>
         is a pair such as
        <code>
          (2.4,-5)
        </code>
         giving the x- and y-coordinates. A
        <dfn>
          coordinate
        </dfn>
         is a not a length, it is a real number (it may have a decimal point or a minus sign). It specifies a length in multiples of the unit length
        <code>
          \unitlength
        </code>
        , so if
        <code>
          \unitlength
        </code>
         has been set to
        <code>
          1cm
        </code>
        , then the coordinate
        <code>
          2.54
        </code>
         specifies a length of 2.54 centimeters.
      </para>
      <paraDefault handler: &latex;
Default handler: &textrsquo;
>
        s default for
        <code>
          \unitlength
        </code>
         is
        <code>
          1pt
        </code>
        . It is a rigid length (
        <pxref label="Lengths">
          <xrefnodename>
            Lengths
          </xrefnodename>
        </pxref>
        ). Change it with the
        <code>
          \setlength
        </code>
         command (
        <pxref label="_005csetlength">
          <xrefnodename>
            \setlength
          </xrefnodename>
        </pxref>
        ). Make this change only outside of a
        <code>
          picture
        </code>
         environment.
      </para>
      <para>
        The
        <code>
          picture
        </code>
         environment supports using standard arithmetic expressions as well as numbers.
      </para>
      <para>
        Coordinates are given with respect to an origin, which is by default at the lower-left corner of the picture. Note that when a position appears as an argument, as with
        <code>
          \put(1,2)
Default handler: &lbrace;
          ...
Default handler: &rbrace;
        </code>
        , it is not enclosed in braces since the parentheses serve to delimit the argument. Also, unlike in some computer graphics systems, larger y-coordinates are further up the page, for example,
        <math>
          y = 1
        </math>
         is
        <emph>
          above
        </emph>
        <math>
          y = 0
        </math>
        .
      </para>
      <para>
        There are four ways to put things in a picture:
        <code>
          \put
        </code>
        ,
        <code>
          \multiput
        </code>
        ,
        <code>
          \qbezier
        </code>
        , and
        <code>
          \graphpaper
        </code>
        . The most often used is
        <code>
          \put
        </code>
        . This
      </para>
      <example endspaces=" ">
        <pre xml:space="preserve">
          \put(11.3,-0.3)
Default handler: &lbrace;
          ...
Default handler: &rbrace;
        </pre>
      </example>
      <noindent/>
      <para>
        places the object with its reference point at coordinates
        <math>
          (11.3,-0.3)
        </math>
        . The reference points for various objects will be described below.
        <findex index="fn" spaces=" ">
          <indexterm index="fn" number="373" mergedindex="cp">
            LR box
          </indexterm>
        </findex>
         The
        <code>
          \put
        </code>
         command creates an
        <dfn>
          LR box
        </dfn>
         (
        <pxref label="Modes">
          <xrefnodename>
            Modes
          </xrefnodename>
        </pxref>
        ). Anything that can go in an
        <code>
          \mbox
        </code>
         (
        <pxref label="_005cmbox-_0026-_005cmakebox">
          <xrefnodename>
            \mbox
            &
             \makebox
          </xrefnodename>
        </pxref>
        ) can go in the text argument of the
        <code>
          \put
        </code>
         command. The reference point will be the lower left corner of the box. In this picture
      </para>
      <example endspaces=" ">
        <pre xml:space="preserve">
          \setlength
Default handler: &lbrace;
          \unitlength
Default handler: &rbrace;
Default handler: &lbrace;
          1cm
Default handler: &rbrace;
           ...\begin
Default handler: &lbrace;
          picture
Default handler: &rbrace;
          (1,1) \put(0,0)
Default handler: &lbrace;
          \line(1,0)
Default handler: &lbrace;
          1
Default handler: &rbrace;
Default handler: &rbrace;
           \put(0,0)
Default handler: &lbrace;
          \line(1,1)
Default handler: &lbrace;
          1
Default handler: &rbrace;
Default handler: &rbrace;
           \end
Default handler: &lbrace;
          picture
Default handler: &rbrace;
        </pre>
      </example>
      <noindent/>
      <para>
        the three dots are just slightly left of the point of the angle formed by the two lines. (Also,
        <code>
          \line(1,1)
Default handler: &lbrace;
          1
Default handler: &rbrace;
        </code>
         does not call for a line of length one; rather the line has a change in the x coordinate of 1.)
      </para>
      <para>
        The
        <code>
          \multiput
        </code>
        ,
        <code>
          qbezier
        </code>
        , and
        <code>
          graphpaper
        </code>
         commands are described below.
      </para>
      <para>
        You can also use this environment to place arbitrary material at an exact location. For example:
      </para>
      <example endspaces=" ">
        <pre xml:space="preserve">
          \usepackage
Default handler: &lbrace;
          color,graphicx
Default handler: &rbrace;
           % in preamble ... \begin
Default handler: &lbrace;
          center
Default handler: &rbrace;
           \setlength
Default handler: &lbrace;
          \unitlength
Default handler: &rbrace;
Default handler: &lbrace;
          \textwidth
Default handler: &rbrace;
           \begin
Default handler: &lbrace;
          picture
Default handler: &rbrace;
          (1,1) % leave space, \textwidth wide and tall \put(0,0)
Default handler: &lbrace;
          \includegraphics[width=\textwidth]
Default handler: &lbrace;
          desertedisland.jpg
Default handler: &rbrace;
Default handler: &rbrace;
           \put(0.25,0.35)
Default handler: &lbrace;
          \textcolor
Default handler: &lbrace;
          red
Default handler: &rbrace;
Default handler: &lbrace;
          X Treasure here
Default handler: &rbrace;
Default handler: &rbrace;
           \end
Default handler: &lbrace;
          picture
Default handler: &rbrace;
           \end
Default handler: &lbrace;
          center
Default handler: &rbrace;
        </pre>
      </example>
      <noindent/>
      <para>
        The red
Default handler: &nbsp;
        X will be precisely a quarter of the
        <code>
          \textwidth
        </code>
         from the left margin, and
        <code>
          0.35\textwidth
        </code>
         up from the bottom of the picture. Another example of this usage is to put similar code in the page header to get repeat material on each of a document
Default handler: &textrsquo;
        s pages.
      </para>
      <menu endspaces=" ">
        <menuentry>
          <menuleadingtext>
            *
          </menuleadingtext>
          <menunode>
            \put
          </menunode>
          <menuseparator>
            ::
          </menuseparator>
          <menudescription>
            <pre xml:space="preserve">
              Place an object at a specified place.
            </pre>
          </menudescription>
        </menuentry>
        <menuentry>
          <menuleadingtext>
            *
          </menuleadingtext>
          <menunode>
            \multiput
          </menunode>
          <menuseparator>
            ::
          </menuseparator>
          <menudescription>
            <pre xml:space="preserve">
              Draw multiple instances of an object.
            </pre>
          </menudescription>
        </menuentry>
        <menuentry>
          <menuleadingtext>
            *
          </menuleadingtext>
          <menunode>
            \qbezier
          </menunode>
          <menuseparator>
            ::
          </menuseparator>
          <menudescription>
            <pre xml:space="preserve">
              Draw a quadratic B
              <accent type="acute" bracketed="off">
                e
              </accent>
              zier curve.
            </pre>
          </menudescription>
        </menuentry>
        <menuentry>
          <menuleadingtext>
            *
          </menuleadingtext>
          <menunode>
            \graphpaper
          </menunode>
          <menuseparator>
            ::
          </menuseparator>
          <menudescription>
            <pre xml:space="preserve">
              Draw graph paper.
            </pre>
          </menudescription>
        </menuentry>
        <menuentry>
          <menuleadingtext>
            *
          </menuleadingtext>
          <menunode>
            \line
          </menunode>
          <menuseparator>
            ::
          </menuseparator>
          <menudescription>
            <pre xml:space="preserve">
              Draw a straight line.
            </pre>
          </menudescription>
        </menuentry>
        <menuentry>
          <menuleadingtext>
            *
          </menuleadingtext>
          <menunode>
            \linethickness
          </menunode>
          <menuseparator>
            ::
          </menuseparator>
          <menudescription>
            <pre xml:space="preserve">
              Set thickness of horizontal and vertical lines.
            </pre>
          </menudescription>
        </menuentry>
        <menuentry>
          <menuleadingtext>
            *
          </menuleadingtext>
          <menunode>
            \thinlines
          </menunode>
          <menuseparator>
            ::
          </menuseparator>
          <menudescription>
            <pre xml:space="preserve">
              The default line thickness.
            </pre>
          </menudescription>
        </menuentry>
        <menuentry>
          <menuleadingtext>
            *
          </menuleadingtext>
          <menunode>
            \thicklines
          </menunode>
          <menuseparator>
            ::
          </menuseparator>
          <menudescription>
            <pre xml:space="preserve">
              A heavier line thickness.
            </pre>
          </menudescription>
        </menuentry>
        <menuentry>
          <menuleadingtext>
            *
          </menuleadingtext>
          <menunode>
            \circle
          </menunode>
          <menuseparator>
            ::
          </menuseparator>
          <menudescription>
            <pre xml:space="preserve">
              Draw a circle.
            </pre>
          </menudescription>
        </menuentry>
        <menuentry>
          <menuleadingtext>
            *
          </menuleadingtext>
          <menunode>
            \oval
          </menunode>
          <menuseparator>
            ::
          </menuseparator>
          <menudescription>
            <pre xml:space="preserve">
              Draw an oval.
            </pre>
          </menudescription>
        </menuentry>
        <menuentry>
          <menuleadingtext>
            *
          </menuleadingtext>
          <menunode>
            \shortstack
          </menunode>
          <menuseparator>
            ::
          </menuseparator>
          <menudescription>
            <pre xml:space="preserve">
              Make a stack of objects.
            </pre>
          </menudescription>
        </menuentry>
        <menuentry>
          <menuleadingtext>
            *
          </menuleadingtext>
          <menunode>
            \vector
          </menunode>
          <menuseparator>
            ::
          </menuseparator>
          <menudescription>
            <pre xml:space="preserve">
              Draw a line with an arrow.
            </pre>
          </menudescription>
        </menuentry>
        <menuentry>
          <menuleadingtext>
            *
          </menuleadingtext>
          <menunode>
            \makebox (picture)
          </menunode>
          <menuseparator>
            ::
          </menuseparator>
          <menudescription>
            <pre xml:space="preserve">
              Draw a box of the specified size.
            </pre>
          </menudescription>
        </menuentry>
        <menuentry>
          <menuleadingtext>
            *
          </menuleadingtext>
          <menunode>
            \framebox (picture)
          </menunode>
          <menuseparator>
            ::
          </menuseparator>
          <menudescription>
            <pre xml:space="preserve">
              Draw a box with a frame around it.
            </pre>
          </menudescription>
        </menuentry>
        <menuentry>
          <menuleadingtext>
            *
          </menuleadingtext>
          <menunode>
            \frame
          </menunode>
          <menuseparator>
            ::
          </menuseparator>
          <menudescription>
            <pre xml:space="preserve">
              Draw a frame around an object.
            </pre>
          </menudescription>
        </menuentry>
        <menuentry>
          <menuleadingtext>
            *
          </menuleadingtext>
          <menunode>
            \dashbox
          </menunode>
          <menuseparator>
            ::
          </menuseparator>
          <menudescription>
            <pre xml:space="preserve">
              Draw a dashed box.
            </pre>
          </menudescription>
        </menuentry>
      </menu>
      <node name="_005cput" spaces=" ">
        <nodename>
          \put
        </nodename>
        <nodenext automatic="on">
          \multiput
        </nodenext>
        <nodeup automatic="on">
          picture
        </nodeup>
      </node>
      <subsection spaces=" ">
        <sectiontitle>
          <code>
            \put
          </code>
        </sectiontitle>
        <findex index="fn" spaces=" ">
          <indexterm index="fn" number="374" mergedindex="cp">
            \put
          </indexterm>
        </findex>
        <para>
          Synopsis:
        </para>
        <example endspaces=" ">
          <pre xml:space="preserve">
            \put(
            <var>
              xcoord
            </var>
            ,
            <var>
              ycoord
            </var>
            )
Default handler: &lbrace;
            <var>
              content
            </var>
Default handler: &rbrace;
          </pre>
        </example>
        <para>
          Place
          <var>
            content
          </var>
           at the coordinate (
          <var>
            xcoord
          </var>
          ,
          <var>
            ycoord
          </var>
          ). See the discussion of coordinates and
          <code>
            \unitlength
          </code>
           in
          <ref label="picture">
            <xrefnodename>
              picture
            </xrefnodename>
          </ref>
          . The
          <var>
            content
          </var>
           is processed in LR mode (
          <pxref label="Modes">
            <xrefnodename>
              Modes
            </xrefnodename>
          </pxref>
          ) so it cannot contain line breaks.
        </para>
        <para>
          This includes the text into the
          <code>
            picture
          </code>
          .
        </para>
        <example endspaces=" ">
          <pre xml:space="preserve">
            \put(4.5,2.5)
Default handler: &lbrace;
            Apply the \textit
Default handler: &lbrace;
            unpoke
Default handler: &rbrace;
             move
Default handler: &rbrace;
          </pre>
        </example>
        <para>
          The reference point, the location (4.5,2.5), is the lower left of the text, at the bottom left of the
          <samp>
            A
          </samp>
          .
        </para>
      </subsection>
      <node name="_005cmultiput" spaces=" ">
        <nodename>
          \multiput
        </nodename>
        <nodenext automatic="on">
          \qbezier
        </nodenext>
        <nodeprev automatic="on">
          \put
        </nodeprev>
        <nodeup automatic="on">
          picture
        </nodeup>
      </node>
      <subsection spaces=" ">
        <sectiontitle>
          <code>
            \multiput
          </code>
        </sectiontitle>
        <findex index="fn" spaces=" ">
          <indexterm index="fn" number="375" mergedindex="cp">
            \multiput
          </indexterm>
        </findex>
        <para>
          Synopsis:
        </para>
        <example endspaces=" ">
          <pre xml:space="preserve">
            \multiput(
            <var>
              x
            </var>
            ,
            <var>
              y
            </var>
            )(
            <var>
              delta_x
            </var>
            ,
            <var>
              delta_y
            </var>
            )
Default handler: &lbrace;
            <var>
              num-copies
            </var>
Default handler: &rbrace;
Default handler: &lbrace;
            <var>
              obj
            </var>
Default handler: &rbrace;
          </pre>
        </example>
        <para>
          Copy
          <var>
            obj
          </var>
           a total of
          <var>
            num-copies
          </var>
           times, with an increment of
          <var>
            delta_x,delta_y
          </var>
          . The
          <var>
            obj
          </var>
           first appears at position
          <math>
            (x,y)
          </math>
          , then at
          <math>
            (x+\delta_x,y+\delta_y)
          </math>
          , and so on.
        </para>
        <para>
          This draws a simple grid with every fifth line in bold (see also
          <ref label="_005cgraphpaper">
            <xrefnodename>
              \graphpaper
            </xrefnodename>
          </ref>
          ).
        </para>
        <example endspaces=" ">
          <pre xml:space="preserve">
            \begin
Default handler: &lbrace;
            picture
Default handler: &rbrace;
            (10,10) \linethickness
Default handler: &lbrace;
            0.05mm
Default handler: &rbrace;
             \multiput(0,0)(1,0)
Default handler: &lbrace;
            10
Default handler: &rbrace;
Default handler: &lbrace;
            \line(0,1)
Default handler: &lbrace;
            10
Default handler: &rbrace;
Default handler: &rbrace;
             \multiput(0,0)(0,1)
Default handler: &lbrace;
            10
Default handler: &rbrace;
Default handler: &lbrace;
            \line(1,0)
Default handler: &lbrace;
            10
Default handler: &rbrace;
Default handler: &rbrace;
             \linethickness
Default handler: &lbrace;
            0.5mm
Default handler: &rbrace;
             \multiput(0,0)(5,0)
Default handler: &lbrace;
            3
Default handler: &rbrace;
Default handler: &lbrace;
            \line(0,1)
Default handler: &lbrace;
            10
Default handler: &rbrace;
Default handler: &rbrace;
             \multiput(0,0)(0,5)
Default handler: &lbrace;
            3
Default handler: &rbrace;
Default handler: &lbrace;
            \line(1,0)
Default handler: &lbrace;
            10
Default handler: &rbrace;
Default handler: &rbrace;
             \end
Default handler: &lbrace;
            picture
Default handler: &rbrace;
          </pre>
        </example>
      </subsection>
      <node name="_005cqbezier" spaces=" ">
        <nodename>
          \qbezier
        </nodename>
        <nodenext automatic="on">
          \graphpaper
        </nodenext>
        <nodeprev automatic="on">
          \multiput
        </nodeprev>
        <nodeup automatic="on">
          picture
        </nodeup>
      </node>
      <subsection spaces=" ">
        <sectiontitle>
          <code>
            \qbezier
          </code>
        </sectiontitle>
        <findex index="fn" spaces=" ">
          <indexterm index="fn" number="376" mergedindex="cp">
            \qbezier
          </indexterm>
        </findex>
        <para>
          Synopsis:
        </para>
        <example endspaces=" ">
          <pre xml:space="preserve">
            \qbezier(
            <var>
              x1
            </var>
            ,
            <var>
              y1
            </var>
            )(
            <var>
              x2
            </var>
            ,
            <var>
              y2
            </var>
            )(
            <var>
              x3
            </var>
            ,
            <var>
              y3
            </var>
            ) \qbezier[
            <var>
              num
            </var>
            ](
            <var>
              x1
            </var>
            ,
            <var>
              y1
            </var>
            )(
            <var>
              x2
            </var>
            ,
            <var>
              y2
            </var>
            )(
            <var>
              x3
            </var>
            ,
            <var>
              y3
            </var>
            )
          </pre>
        </example>
        <para>
          Draw a quadratic Bezier curve whose control points are given by the three required arguments
          <code>
            (
            <var>
              x1
            </var>
            ,
            <var>
              y1
            </var>
            )
          </code>
          ,
          <code>
            (
            <var>
              x2
            </var>
            ,
            <var>
              y2
            </var>
            )
          </code>
          , and
          <code>
            (
            <var>
              x3
            </var>
            ,
            <var>
              y3
            </var>
            )
          </code>
          . That is, the curve runs from
          <var>
            (x1,y1)
          </var>
           to
          <var>
            (x3,y3)
          </var>
          , is quadratic, and is such that the tangent line at
          <var>
            (x1,y1)
          </var>
           passes through
          <var>
            (x2,y2)
          </var>
          , as does the tangent line at
          <var>
            (x3,y3)
          </var>
          .
        </para>
        <para>
          This draws a curve from the coordinate (1,1) to (1,0).
        </para>
        <example endspaces=" ">
          <pre xml:space="preserve">
            \qbezier(1,1)(1.25,0.75)(1,0)
          </pre>
        </example>
        <noindent/>
        <para>
          The curve
Default handler: &textrsquo;
          s tangent line at (1,1) contains (1.25,0.75), as does the curve
Default handler: &textrsquo;
          s tangent line at (1,0).
        </para>
        <para>
          The optional argument
          <var>
            num
          </var>
           gives the number of calculated intermediate points. The default is to draw a smooth curve whose maximum number of points is
          <code>
            \qbeziermax
          </code>
           (change this value with
          <code>
            \renewcommand
          </code>
          ).
        </para>
        <para>
          This draws a rectangle with a wavy top, using
          <code>
            \qbezier
          </code>
           for that curve.
        </para>
        <example endspaces=" ">
          <pre xml:space="preserve">
            \begin
Default handler: &lbrace;
            picture
Default handler: &rbrace;
            (8,4) \put(0,0)
Default handler: &lbrace;
            \vector(1,0)
Default handler: &lbrace;
            8
Default handler: &rbrace;
Default handler: &rbrace;
             % x axis \put(0,0)
Default handler: &lbrace;
            \vector(0,1)
Default handler: &lbrace;
            4
Default handler: &rbrace;
Default handler: &rbrace;
             % y axis \put(2,0)
Default handler: &lbrace;
            \line(0,1)
Default handler: &lbrace;
            3
Default handler: &rbrace;
Default handler: &rbrace;
             % left side \put(4,0)
Default handler: &lbrace;
            \line(0,1)
Default handler: &lbrace;
            3.5
Default handler: &rbrace;
Default handler: &rbrace;
             % right side \qbezier(2,3)(2.5,2.9)(3,3.25) \qbezier(3,3.25)(3.5,3.6)(4,3.5) \thicklines % below here, lines are twice as thick \put(2,3)
Default handler: &lbrace;
            \line(4,1)
Default handler: &lbrace;
            2
Default handler: &rbrace;
Default handler: &rbrace;
             \put(4.5,2.5)
Default handler: &lbrace;
            \framebox
Default handler: &lbrace;
            Trapezoidal Rule
Default handler: &rbrace;
Default handler: &rbrace;
             \end
Default handler: &lbrace;
            picture
Default handler: &rbrace;
          </pre>
        </example>
      </subsection>
      <node name="_005cgraphpaper" spaces=" ">
        <nodename>
          \graphpaper
        </nodename>
        <nodenext automatic="on">
          \line
        </nodenext>
        <nodeprev automatic="on">
          \qbezier
        </nodeprev>
        <nodeup automatic="on">
          picture
        </nodeup>
      </node>
      <subsection spaces=" ">
        <sectiontitle>
          <code>
            \graphpaper
          </code>
        </sectiontitle>
        <findex index="fn" spaces=" ">
          <indexterm index="fn" number="377" mergedindex="cp">
            \graphpaper
          </indexterm>
        </findex>
        <para>
          Synopsis:
        </para>
        <example endspaces=" ">
          <pre xml:space="preserve">
            \graphpaper(
            <var>
              x_init
            </var>
            ,
            <var>
              y_init
            </var>
            )(
            <var>
              x_dimen
            </var>
            ,
            <var>
              y_dimen
            </var>
            ) \graphpaper[
            <var>
              spacing
            </var>
            ](
            <var>
              x_init
            </var>
            ,
            <var>
              y_init
            </var>
            )(
            <var>
              x_dimen
            </var>
            ,
            <var>
              y_dimen
            </var>
            )
          </pre>
        </example>
        <cindex index="cp" spaces=" ">
          <indexterm index="cp" number="379">
            <r>
              package
            </r>
            ,
            <code>
              graphpap
            </code>
          </indexterm>
        </cindex>
        <cindex index="cp" spaces=" ">
          <indexterm index="cp" number="380">
            <code>
              graphpap
            </code>
            <r>
              package
            </r>
          </indexterm>
        </cindex>
        <para>
          Draw a coordinate grid. Requires the
          <code>
            graphpap
          </code>
           package. The grid
Default handler: &textrsquo;
          s origin is
          <code>
            (
            <var>
              x_init
            </var>
            ,
            <var>
              y_init
            </var>
            )
          </code>
          . Grid lines come every
          <var>
            spacing
          </var>
           units (the default is 10). The grid extends
          <var>
            x_dimen
          </var>
           units to the right and
          <var>
            y_dimen
          </var>
           units up. All arguments must be positive integers.
        </para>
        <para>
          This make a grid with seven vertical lines and eleven horizontal lines.
        </para>
        <example endspaces=" ">
          <pre xml:space="preserve">
            \usepackage
Default handler: &lbrace;
            graphpap
Default handler: &rbrace;
             % in preamble ... \begin
Default handler: &lbrace;
            picture
Default handler: &rbrace;
            (6,20) % in document body \graphpaper[2](0,0)(12,20) \end
Default handler: &lbrace;
            picture
Default handler: &rbrace;
          </pre>
        </example>
        <noindent/>
        <para>
          The lines are numbered every ten units.
        </para>
      </subsection>
      <node name="_005cline" spaces=" ">
        <nodename>
          \line
        </nodename>
        <nodenext automatic="on">
          \linethickness
        </nodenext>
        <nodeprev automatic="on">
          \graphpaper
        </nodeprev>
        <nodeup automatic="on">
          picture
        </nodeup>
      </node>
      <subsection spaces=" ">
        <sectiontitle>
          <code>
            \line
          </code>
        </sectiontitle>
        <findex index="fn" spaces=" ">
          <indexterm index="fn" number="378" mergedindex="cp">
            \line
          </indexterm>
        </findex>
        <para>
          Synopsis:
        </para>
        <example endspaces=" ">
          <pre xml:space="preserve">
            \line(
            <var>
              x_run
            </var>
            ,
            <var>
              y_rise
            </var>
            )
Default handler: &lbrace;
            <var>
              travel
            </var>
Default handler: &rbrace;
          </pre>
        </example>
        <para>
          Draw a line. It slopes such that it vertically rises
          <var>
            y_rise
          </var>
           for every horizontal
          <var>
            x_run
          </var>
          . The
          <var>
            travel
          </var>
           is the total horizontal change
Default handler: &textmdash;
          it is not the length of the vector, it is the change in
          <math>
            x
          </math>
          . In the special case of vertical lines, where (
          <var>
            x_run
          </var>
          ,
          <var>
            y_rise
          </var>
          )=(0,1), the
          <var>
            travel
          </var>
           gives the change in
          <math>
            y
          </math>
          .
        </para>
        <para>
          This draws a line starting at coordinates (1,3).
        </para>
        <example endspaces=" ">
          <pre xml:space="preserve">
            \put(1,3)
Default handler: &lbrace;
            \line(2,5)
Default handler: &lbrace;
            4
Default handler: &rbrace;
Default handler: &rbrace;
          </pre>
        </example>
        <noindent/>
        <para>
          For every over 2, this line will go up 5. Because
          <var>
            travel
          </var>
           specifies that this goes over 4, it must go up
Default handler: &nbsp;
          10. Thus its endpoint is
          <math>
            (1,3)+(4,10)=(5,13)
          </math>
          . In particular, note that
          <math>
            <var>
              travel
            </var>
            =4
          </math>
           is not the length of the line, it is the change in
          <math>
            x
          </math>
          .
        </para>
        <para>
          The arguments
          <var>
            x_run
          </var>
           and
          <var>
            y_rise
          </var>
           are integers that can be positive, negative, or zero. (If both are 0 then
Default handler: &latex;
           treats the second as 1.) With
          <code>
            \put(
            <var>
              x_init
            </var>
            ,
            <var>
              y_init
            </var>
            )
Default handler: &lbrace;
            \line(
            <var>
              x_run
            </var>
            ,
            <var>
              y_rise
            </var>
            )
Default handler: &lbrace;
            <var>
              travel
            </var>
Default handler: &rbrace;
Default handler: &rbrace;
          </code>
          , if
          <var>
            x_run
          </var>
           is negative then the line
Default handler: &textrsquo;
          s ending point has a first coordinate that is less than
          <var>
            x_init
          </var>
          . If
          <var>
            y_rise
          </var>
           is negative then the line
Default handler: &textrsquo;
          s ending point has a second coordinate that is less than
          <var>
            y_init
          </var>
          .
        </para>
        <para>
          If
          <var>
            travel
          </var>
           is negative then you get
          <code>
            LaTeX Error: Bad \line or \vector argument.
          </code>
        </para>
        <cindex index="cp" spaces=" ">
          <indexterm index="cp" number="381">
            graphics packages
          </indexterm>
        </cindex>
        <cindex index="cp" spaces=" ">
          <indexterm index="cp" number="382">
            <r>
              package
            </r>
            ,
            <code>
              pict2e
            </code>
          </indexterm>
        </cindex>
        <cindex index="cp" spaces=" ">
          <indexterm index="cp" number="383">
            <code>
              pict2e
            </code>
            <r>
              package
            </r>
          </indexterm>
        </cindex>
        <cindex index="cp" spaces=" ">
          <indexterm index="cp" number="384">
            <r>
              package
            </r>
            ,
            <code>
              TikZ
            </code>
          </indexterm>
        </cindex>
        <cindex index="cp" spaces=" ">
          <indexterm index="cp" number="385">
            <code>
              TikZ
            </code>
            <r>
              package
            </r>
          </indexterm>
        </cindex>
        <cindex index="cp" spaces=" ">
          <indexterm index="cp" number="386">
            <r>
              package
            </r>
            ,
            <code>
              PSTricks
            </code>
          </indexterm>
        </cindex>
        <cindex index="cp" spaces=" ">
          <indexterm index="cp" number="387">
            <code>
              PSTricks
            </code>
            <r>
              package
            </r>
          </indexterm>
        </cindex>
        <cindex index="cp" spaces=" ">
          <indexterm index="cp" number="388">
            <r>
              package
            </r>
            ,
            <code>
              MetaPost
            </code>
          </indexterm>
        </cindex>
        <cindex index="cp" spaces=" ">
          <indexterm index="cp" number="389">
            <code>
              MetaPost
            </code>
            <r>
              package
            </r>
          </indexterm>
        </cindex>
        <cindex index="cp" spaces=" ">
          <indexterm index="cp" number="390">
            <r>
              package
            </r>
            ,
            <code>
              Asymptote
            </code>
          </indexterm>
        </cindex>
        <cindex index="cp" spaces=" ">
          <indexterm index="cp" number="391">
            <code>
              Asymptote
            </code>
            <r>
              package
            </r>
          </indexterm>
        </cindex>
        <para>
          Standard
Default handler: &latex;
           can only draw lines with a limited range of slopes because these lines are made by putting together line segments from pre-made fonts. The two numbers
          <var>
            x_run
          </var>
           and
          <var>
            y_rise
          </var>
           must have integer values from
Default handler: &minus;
          6 through
Default handler: &nbsp;
          6. Also, they must be relatively prime, so that
          <var>
            (x_run,y_rise)
          </var>
           can be (2,1) but not (4,2) (if you choose the latter then instead of lines you get sequences of arrowheads; the solution is to switch to the former). To get lines of arbitrary slope and plenty of other shapes in a system like
          <code>
            picture
          </code>
          , see the package
          <code>
            pict2e
          </code>
           (
          <url>
            <urefurl>
              https://ctan.org/pkg/pict2e
            </urefurl>
          </url>
          ). Another solution is to use a full-featured graphics system such as TikZ, PSTricks, MetaPost, or Asymptote.
        </para>
      </subsection>
      <node name="_005clinethickness" spaces=" ">
        <nodename>
          \linethickness
        </nodename>
        <nodenext automatic="on">
          \thinlines
        </nodenext>
        <nodeprev automatic="on">
          \line
        </nodeprev>
        <nodeup automatic="on">
          picture
        </nodeup>
      </node>
      <subsection spaces=" ">
        <sectiontitle>
          <code>
            \linethickness
          </code>
        </sectiontitle>
        <findex index="fn" spaces=" ">
          <indexterm index="fn" number="379" mergedindex="cp">
            \linethickness
          </indexterm>
        </findex>
        <para>
          Synopsis:
        </para>
        <example endspaces=" ">
          <pre xml:space="preserve">
            \linethickness
Default handler: &lbrace;
            <var>
              dim
            </var>
Default handler: &rbrace;
          </pre>
        </example>
        <para>
          Declares the thickness of subsequent horizontal and vertical lines in a picture to be
          <var>
            dim
          </var>
          , which must be a positive length (
          <pxref label="Lengths">
            <xrefnodename>
              Lengths
            </xrefnodename>
          </pxref>
          ). It differs from
          <code>
            \thinlines
          </code>
           and
          <code>
            \thicklines
          </code>
           in that it does not affect the thickness of slanted lines, circles, or ovals (
          <pxref label="_005coval">
            <xrefnodename>
              \oval
            </xrefnodename>
          </pxref>
          ).
        </para>
      </subsection>
      <node name="_005cthinlines" spaces=" ">
        <nodename>
          \thinlines
        </nodename>
        <nodenext automatic="on">
          \thicklines
        </nodenext>
        <nodeprev automatic="on">
          \linethickness
        </nodeprev>
        <nodeup automatic="on">
          picture
        </nodeup>
      </node>
      <subsection spaces=" ">
        <sectiontitle>
          <code>
            \thinlines
          </code>
        </sectiontitle>
        <findex index="fn" spaces=" ">
          <indexterm index="fn" number="380" mergedindex="cp">
            \thinlines
          </indexterm>
        </findex>
        <para>
          Declaration to set the thickness of subsequent lines, circles, and ovals in a picture environment to be 0.4
          <dmn>
            pt
          </dmn>
          . This is the default thickness, so this command is unnecessary unless the thickness has been changed with either
          <ref label="_005clinethickness">
            <xrefnodename>
              \linethickness
            </xrefnodename>
          </ref>
           or
          <ref label="_005cthicklines">
            <xrefnodename>
              \thicklines
            </xrefnodename>
          </ref>
          .
        </para>
      </subsection>
      <node name="_005cthicklines" spaces=" ">
        <nodename>
          \thicklines
        </nodename>
        <nodenext automatic="on">
          \circle
        </nodenext>
        <nodeprev automatic="on">
          \thinlines
        </nodeprev>
        <nodeup automatic="on">
          picture
        </nodeup>
      </node>
      <subsection spaces=" ">
        <sectiontitle>
          <code>
            \thicklines
          </code>
        </sectiontitle>
        <findex index="fn" spaces=" ">
          <indexterm index="fn" number="381" mergedindex="cp">
            \thicklines
          </indexterm>
        </findex>
        <para>
          Declaration to set the thickness of subsequent lines, circles, and ovals in a picture environment to be 0.8
          <dmn>
            pt
          </dmn>
          . See also
          <ref label="_005clinethickness">
            <xrefnodename>
              \linethickness
            </xrefnodename>
          </ref>
           and
          <ref label="_005cthinlines">
            <xrefnodename>
              \thinlines
            </xrefnodename>
          </ref>
          . This command is illustrated in the Trapezoidal Rule example of
          <ref label="_005cqbezier">
            <xrefnodename>
              \qbezier
            </xrefnodename>
          </ref>
          .
        </para>
      </subsection>
      <node name="_005ccircle" spaces=" ">
        <nodename>
          \circle
        </nodename>
        <nodenext automatic="on">
          \oval
        </nodenext>
        <nodeprev automatic="on">
          \thicklines
        </nodeprev>
        <nodeup automatic="on">
          picture
        </nodeup>
      </node>
      <subsection spaces=" ">
        <sectiontitle>
          <code>
            \circle
          </code>
        </sectiontitle>
        <findex index="fn" spaces=" ">
          <indexterm index="fn" number="382" mergedindex="cp">
            \circle
          </indexterm>
        </findex>
        <para>
          Synopsis:
        </para>
        <example endspaces=" ">
          <pre xml:space="preserve">
            \circle
Default handler: &lbrace;
            <var>
              diameter
            </var>
Default handler: &rbrace;
             \circle*
Default handler: &lbrace;
            <var>
              diameter
            </var>
Default handler: &rbrace;
          </pre>
        </example>
        <para>
          Produces a circle with a diameter as close as possible to the specified one. The
          <code>
            *
          </code>
Default handler: &nbsp;
          form produces a filled-in circle.
        </para>
        <para>
          This draws a circle of radius 6, centered at
          <code>
            (5,7)
          </code>
          .
        </para>
        <example endspaces=" ">
          <pre xml:space="preserve">
            \put(5,7)
Default handler: &lbrace;
            \circle
Default handler: &lbrace;
            6
Default handler: &rbrace;
Default handler: &rbrace;
          </pre>
        </example>
        <para>
          The available radii for
          <code>
            \circle
          </code>
           are, in points, the even numbers from 2 to 20, inclusive. For
          <code>
            \circle*
          </code>
           they are all the integers from 1 to 15.
        </para>
      </subsection>
      <node name="_005coval" spaces=" ">
        <nodename>
          \oval
        </nodename>
        <nodenext automatic="on">
          \shortstack
        </nodenext>
        <nodeprev automatic="on">
          \circle
        </nodeprev>
        <nodeup automatic="on">
          picture
        </nodeup>
      </node>
      <subsection spaces=" ">
        <sectiontitle>
          <code>
            \oval
          </code>
        </sectiontitle>
        <findex index="fn" spaces=" ">
          <indexterm index="fn" number="383" mergedindex="cp">
            \oval
          </indexterm>
        </findex>
        <para>
          Synopsis:
        </para>
        <example endspaces=" ">
          <pre xml:space="preserve">
            \oval(
            <var>
              width
            </var>
            ,
            <var>
              height
            </var>
            ) \oval(
            <var>
              width
            </var>
            ,
            <var>
              height
            </var>
            )[
            <var>
              portion
            </var>
            ]
          </pre>
        </example>
        <para>
          Produce a rectangle with rounded corners, hereinafter referred to as an
          <dfn>
            oval
          </dfn>
          . The optional argument
          <var>
            portion
          </var>
           allows you to produce only half or a quarter of the oval. For half an oval take
          <var>
            portion
          </var>
           to be one of these.
        </para>
        <table commandarg="code" spaces=" " endspaces=" ">
          <tableentry>
            <tableterm>
              <item spaces=" ">
                <itemformat command="code">
                  t
                </itemformat>
              </item>
            </tableterm>
            <tableitem>
              <para>
                top half
              </para>
            </tableitem>
          </tableentry>
          <tableentry>
            <tableterm>
              <item spaces=" ">
                <itemformat command="code">
                  b
                </itemformat>
              </item>
            </tableterm>
            <tableitem>
              <para>
                bottom half
              </para>
            </tableitem>
          </tableentry>
          <tableentry>
            <tableterm>
              <item spaces=" ">
                <itemformat command="code">
                  r
                </itemformat>
              </item>
            </tableterm>
            <tableitem>
              <para>
                right half
              </para>
            </tableitem>
          </tableentry>
          <tableentry>
            <tableterm>
              <item spaces=" ">
                <itemformat command="code">
                  l
                </itemformat>
              </item>
            </tableterm>
            <tableitem>
              <para>
                left half
              </para>
            </tableitem>
          </tableentry>
        </table>
        <para>
          Produce only one quarter of the oval by setting
          <var>
            portion
          </var>
           to
          <code>
            tr
          </code>
          ,
          <code>
            br
          </code>
          ,
          <code>
            bl
          </code>
          , or
          <code>
            tl
          </code>
          .
        </para>
        <para>
          This draws the top half of an oval that is 3 wide and 7 tall.
        </para>
        <example endspaces=" ">
          <pre xml:space="preserve">
            \put(5,7)
Default handler: &lbrace;
            \oval(3,7)[t]
Default handler: &rbrace;
          </pre>
        </example>
        <noindent/>
        <para>
          The (5,7) is the center of the entire oval, not just the center of the top half.
        </para>
        <para>
          These shapes are not ellipses. They are rectangles whose corners are made with quarter circles. These circles have a maximum radius of 20
          <dmn>
            pt
          </dmn>
           (
          <pxref label="_005ccircle">
            <xrefnodename>
              \circle
            </xrefnodename>
          </pxref>
           for the sizes). Thus large ovals are just frames with a small amount of corner rounding.
        </para>
      </subsection>
      <node name="_005cshortstack" spaces=" ">
        <nodename>
          \shortstack
        </nodename>
        <nodenext automatic="on">
          \vector
        </nodenext>
        <nodeprev automatic="on">
          \oval
        </nodeprev>
        <nodeup automatic="on">
          picture
        </nodeup>
      </node>
      <subsection spaces=" ">
        <sectiontitle>
          <code>
            \shortstack
          </code>
        </sectiontitle>
        <findex index="fn" spaces=" ">
          <indexterm index="fn" number="384" mergedindex="cp">
            \shortstack
          </indexterm>
        </findex>
        <para>
          Synopsis:
        </para>
        <example endspaces=" ">
          <pre xml:space="preserve">
            \shortstack[
            <var>
              position
            </var>
            ]
Default handler: &lbrace;
            <var>
              line 1
            </var>
             \\ ...
Default handler: &rbrace;
          </pre>
        </example>
        <para>
          Produce a vertical stack of objects.
        </para>
        <para>
          This labels the
          <math>
            y
          </math>
           axis by writing the word
          <samp>
            <math>
              y
            </math>
          </samp>
           above the word
          <samp>
            axis
          </samp>
          .
        </para>
        <example endspaces=" ">
          <pre xml:space="preserve">
            \setlength
Default handler: &lbrace;
            \unitlength
Default handler: &rbrace;
Default handler: &lbrace;
            1cm
Default handler: &rbrace;
             \begin
Default handler: &lbrace;
            picture
Default handler: &rbrace;
            (5,2.5)(-0.75,0) \put(0,0)
Default handler: &lbrace;
            \vector(1,0)
Default handler: &lbrace;
            4
Default handler: &rbrace;
Default handler: &rbrace;
             % x axis \put(0,0)
Default handler: &lbrace;
            \vector(0,1)
Default handler: &lbrace;
            2
Default handler: &rbrace;
Default handler: &rbrace;
             % y \put(-0.2,2)
Default handler: &lbrace;
            \makebox(0,0)[r]
Default handler: &lbrace;
            \shortstack[r]
Default handler: &lbrace;
            $y$\\ axis
Default handler: &rbrace;
Default handler: &rbrace;
Default handler: &rbrace;
             \end
Default handler: &lbrace;
            picture
Default handler: &rbrace;
          </pre>
        </example>
        <noindent/>
        <para>
          For a short stack, the reference point is the lower left of the stack. In the above example the
          <code>
            \makebox
          </code>
           (
          <pxref label="_005cmbox-_0026-_005cmakebox">
            <xrefnodename>
              \mbox
              &
               \makebox
            </xrefnodename>
          </pxref>
          ) puts the stack flush right in a zero width box so in total the short stack sits slightly to the left of the
          <math>
            y
          </math>
Default handler: &nbsp;
          axis.
        </para>
        <para>
          The valid positions are:
        </para>
        <table commandarg="code" spaces=" " endspaces=" ">
          <tableentry>
            <tableterm>
              <item spaces=" ">
                <itemformat command="code">
                  r
                </itemformat>
              </item>
            </tableterm>
            <tableitem>
              <para>
                Make objects flush right
              </para>
            </tableitem>
          </tableentry>
          <tableentry>
            <tableterm>
              <item spaces=" ">
                <itemformat command="code">
                  l
                </itemformat>
              </item>
            </tableterm>
            <tableitem>
              <para>
                Make objects flush left
              </para>
            </tableitem>
          </tableentry>
          <tableentry>
            <tableterm>
              <item spaces=" ">
                <itemformat command="code">
                  c
                </itemformat>
              </item>
            </tableterm>
            <tableitem>
              <para>
                Center objects (default)
              </para>
            </tableitem>
          </tableentry>
        </table>
        <findex index="fn" spaces=" ">
          <indexterm index="fn" number="385" mergedindex="cp">
            \\
            <r>
              (for
              <code>
                \shortstack
              </code>
               objects)
            </r>
          </indexterm>
        </findex>
        <para>
          Separate objects into lines with
          <code>
            \\
          </code>
          . These stacks are short in that, unlike in a
          <code>
            tabular
          </code>
           or
          <code>
            array
          </code>
           environment, here the rows are not spaced out to be of even baseline skips. Thus, in
          <code>
            \shortstack
Default handler: &lbrace;
            X\\o\\o\\X
Default handler: &rbrace;
          </code>
           the first and last rows are taller than the middle two, and therefore the baseline skip between the two middle rows is smaller than that between the third and last row. You can adjust row heights and depths either by putting in the usual interline spacing with
          <code>
            \shortstack
Default handler: &lbrace;
            X\\ \strut o\\o\\X
Default handler: &rbrace;
          </code>
           (
          <pxref label="_005cstrut">
            <xrefnodename>
              \strut
            </xrefnodename>
          </pxref>
          ), or explicitly, via an zero-width box
          <code>
            \shortstack
Default handler: &lbrace;
            X \\ \rule
Default handler: &lbrace;
            0pt
Default handler: &rbrace;
Default handler: &lbrace;
            12pt
Default handler: &rbrace;
             o\\o\\X
Default handler: &rbrace;
          </code>
           or by using
          <code>
            \\
          </code>
Default handler: &textrsquo;
          s optional argument
          <code>
            \shortstack
Default handler: &lbrace;
            X\\[2pt] o\\o\\X
Default handler: &rbrace;
          </code>
          .
        </para>
        <para>
          The
          <code>
            \shortstack
          </code>
           command is also available outside the
          <code>
            picture
          </code>
           environment.
        </para>
      </subsection>
      <node name="_005cvector" spaces=" ">
        <nodename>
          \vector
        </nodename>
        <nodenext automatic="on">
          \makebox (picture)
        </nodenext>
        <nodeprev automatic="on">
          \shortstack
        </nodeprev>
        <nodeup automatic="on">
          picture
        </nodeup>
      </node>
      <subsection spaces=" ">
        <sectiontitle>
          <code>
            \vector
          </code>
        </sectiontitle>
        <findex index="fn" spaces=" ">
          <indexterm index="fn" number="386" mergedindex="cp">
            \vector
          </indexterm>
        </findex>
        <para>
          Synopsis:
        </para>
        <example endspaces=" ">
          <pre xml:space="preserve">
            \vector(
            <var>
              x_run
            </var>
            ,
            <var>
              y_rise
            </var>
            )
Default handler: &lbrace;
            <var>
              travel
            </var>
Default handler: &rbrace;
          </pre>
        </example>
        <para>
          Draw a line ending in an arrow. The slope of that line is: it vertically rises
          <var>
            y_rise
          </var>
           for every horizontal
          <var>
            x_run
          </var>
          . The
          <var>
            travel
          </var>
           is the total horizontal change
Default handler: &textmdash;
          it is not the length of the vector, it is the change in
          <math>
            x
          </math>
          . In the special case of vertical vectors, if (
          <var>
            x_run
          </var>
          ,
          <var>
            y_rise
          </var>
          )=(0,1), then
          <var>
            travel
          </var>
           gives the change in
          <math>
            y
          </math>
          .
        </para>
        <para>
          For an example see
          <ref label="picture">
            <xrefnodename>
              picture
            </xrefnodename>
          </ref>
          .
        </para>
        <para>
          For elaboration on
          <var>
            x_run
          </var>
           and
          <var>
            y_rise
          </var>
           see
          <ref label="_005cline">
            <xrefnodename>
              \line
            </xrefnodename>
          </ref>
          . As there, the values of
          <var>
            x_run
          </var>
           and
          <var>
            y_rise
          </var>
           are limited. For
          <code>
            \vector
          </code>
           you must chooses integers between
Default handler: &minus;
          4 and 4, inclusive. Also, the two you choose must be relatively prime. Thus,
          <code>
            \vector(2,1)
Default handler: &lbrace;
            4
Default handler: &rbrace;
          </code>
           is acceptable but
          <code>
            \vector(4,2)
Default handler: &lbrace;
            4
Default handler: &rbrace;
          </code>
           is not (if you use the latter then you get a sequence of arrowheads).
        </para>
      </subsection>
      <node name="_005cmakebox-_0028picture_0029" spaces=" ">
        <nodename>
          \makebox (picture)
        </nodename>
        <nodenext automatic="on">
          \framebox (picture)
        </nodenext>
        <nodeprev automatic="on">
          \vector
        </nodeprev>
        <nodeup automatic="on">
          picture
        </nodeup>
      </node>
      <subsection spaces=" ">
        <sectiontitle>
          <code>
            \makebox
          </code>
           (picture)
        </sectiontitle>
        <findex index="fn" spaces=" ">
          <indexterm index="fn" number="387" mergedindex="cp">
            \makebox
            <r>
              (for
              <code>
                picture
              </code>
              )
            </r>
          </indexterm>
        </findex>
        <para>
          Synopsis:
        </para>
        <example endspaces=" ">
          <pre xml:space="preserve">
            \makebox(
            <var>
              rec-width
            </var>
            ,
            <var>
              rec-height
            </var>
            )
Default handler: &lbrace;
            <var>
              text
            </var>
Default handler: &rbrace;
             \makebox(
            <var>
              rec-width
            </var>
            ,
            <var>
              rec-height
            </var>
            )[
            <var>
              position
            </var>
            ]
Default handler: &lbrace;
            <var>
              text
            </var>
Default handler: &rbrace;
          </pre>
        </example>
        <para>
          Make a box to hold
          <var>
            text
          </var>
          . This command fits with the
          <code>
            picture
          </code>
           environment, although you can use it outside of there, because
          <var>
            rec-width
          </var>
           and
          <var>
            rec-height
          </var>
           are numbers specifying distances in terms of the
          <code>
            \unitlength
          </code>
           (
          <pxref label="picture">
            <xrefnodename>
              picture
            </xrefnodename>
          </pxref>
          ). This command is similar to the normal
          <code>
            \makebox
          </code>
           command (
          <pxref label="_005cmbox-_0026-_005cmakebox">
            <xrefnodename>
              \mbox
              &
               \makebox
            </xrefnodename>
          </pxref>
          ) except here that you must specify the width and height. This command is fragile (
          <pxref label="_005cprotect">
            <xrefnodename>
              \protect
            </xrefnodename>
          </pxref>
          ).
        </para>
        <para>
          This makes a box of length 3.5 times
          <code>
            \unitlength
          </code>
           and height 4 times
          <code>
            \unitlength
          </code>
          .
        </para>
        <example endspaces=" ">
          <pre xml:space="preserve">
            \put(1,2)
Default handler: &lbrace;
            \makebox(3.5,4)
Default handler: &lbrace;
            ...
Default handler: &rbrace;
Default handler: &rbrace;
          </pre>
        </example>
        <para>
          The optional argument
          <code>
            <var>
              position
            </var>
          </code>
           specifies where in the box the
          <var>
            text
          </var>
           appears. The default is to center it, both horizontally and vertically. To place it somewhere else, use a string with one or two of these letters.
        </para>
        <table commandarg="code" spaces=" " endspaces=" ">
          <tableentry>
            <tableterm>
              <item spaces=" ">
                <itemformat command="code">
                  t
                </itemformat>
              </item>
            </tableterm>
            <tableitem>
              <para>
                Puts
                <var>
                  text
                </var>
                 the top of the box.
              </para>
            </tableitem>
          </tableentry>
          <tableentry>
            <tableterm>
              <item spaces=" ">
                <itemformat command="code">
                  b
                </itemformat>
              </item>
            </tableterm>
            <tableitem>
              <para>
                Put
                <var>
                  text
                </var>
                 at the bottom.
              </para>
            </tableitem>
          </tableentry>
          <tableentry>
            <tableterm>
              <item spaces=" ">
                <itemformat command="code">
                  l
                </itemformat>
              </item>
            </tableterm>
            <tableitem>
              <para>
                Put
                <var>
                  text
                </var>
                 on the left.
              </para>
            </tableitem>
          </tableentry>
          <tableentry>
            <tableterm>
              <item spaces=" ">
                <itemformat command="code">
                  r
                </itemformat>
              </item>
            </tableterm>
            <tableitem>
              <para>
                Put
                <var>
                  text
                </var>
                 on the right.
              </para>
            </tableitem>
          </tableentry>
        </table>
      </subsection>
      <node name="_005cframebox-_0028picture_0029" spaces=" ">
        <nodename>
          \framebox (picture)
        </nodename>
        <nodenext automatic="on">
          \frame
        </nodenext>
        <nodeprev automatic="on">
          \makebox (picture)
        </nodeprev>
        <nodeup automatic="on">
          picture
        </nodeup>
      </node>
      <subsection spaces=" ">
        <sectiontitle>
          <code>
            \framebox
          </code>
           (picture)
        </sectiontitle>
        <findex index="fn" spaces=" ">
          <indexterm index="fn" number="388" mergedindex="cp">
            \framebox
          </indexterm>
        </findex>
        <para>
          Synopsis:
        </para>
        <example endspaces=" ">
          <pre xml:space="preserve">
            \framebox(
            <var>
              rec-width
            </var>
            ,
            <var>
              rec-height
            </var>
            )
Default handler: &lbrace;
            <var>
              text
            </var>
Default handler: &rbrace;
             \framebox(
            <var>
              rec-width
            </var>
            ,
            <var>
              rec-height
            </var>
            )[
            <var>
              position
            </var>
            ]
Default handler: &lbrace;
            <var>
              text
            </var>
Default handler: &rbrace;
          </pre>
        </example>
        <para>
          This is the same as
          <ref label="_005cmakebox-_0028picture_0029">
            <xrefnodename>
              \makebox (picture)
            </xrefnodename>
          </ref>
           except that it puts a frame around the outside of the box that it creates. The reference point is the bottom left corner of the frame. This command fits with the
          <code>
            picture
          </code>
           environment, although you can use it outside of there, because lengths are numbers specifying the distance in terms of the
          <code>
            \unitlength
          </code>
           (
          <pxref label="picture">
            <xrefnodename>
              picture
            </xrefnodename>
          </pxref>
          ). This command is fragile (
          <pxref label="_005cprotect">
            <xrefnodename>
              \protect
            </xrefnodename>
          </pxref>
          ).
        </para>
        <para>
          This example creates a frame 2.5
Default handler: &nbsp;
          inches by 3
Default handler: &nbsp;
          inches and puts the text in the center.
        </para>
        <example endspaces=" ">
          <pre xml:space="preserve">
            \setlength
Default handler: &lbrace;
            \unitlength
Default handler: &rbrace;
Default handler: &lbrace;
            1in
Default handler: &rbrace;
             \framebox(2.5,3)
Default handler: &lbrace;
            test text
Default handler: &rbrace;
          </pre>
        </example>
        <para>
          The required arguments are that the rectangle has overall width
          <var>
            rect-width
          </var>
           units and height
          <var>
            rect-height
          </var>
           units.
        </para>
        <para>
          The optional argument
          <var>
            position
          </var>
           specifies the position of
          <var>
            text
          </var>
          ; see
          <ref label="_005cmakebox-_0028picture_0029">
            <xrefnodename>
              \makebox (picture)
            </xrefnodename>
          </ref>
           for the values that it can take.
        </para>
        <findex index="fn" spaces=" ">
          <indexterm index="fn" number="389" mergedindex="cp">
            \fboxrule
          </indexterm>
        </findex>
        <findex index="fn" spaces=" ">
          <indexterm index="fn" number="390" mergedindex="cp">
            \fboxsep
          </indexterm>
        </findex>
        <para>
          The rule has thickness
          <code>
            \fboxrule
          </code>
           and there is a blank space
          <code>
            \fboxsep
          </code>
           between the frame and the contents of the box.
        </para>
        <para>
          For this command, you must specify the
          <var>
            width
          </var>
           and
          <var>
            height
          </var>
          . If you want to just put a frame around some contents whose dimension is determined in some other way then either use
          <code>
            \fbox
          </code>
           (
          <pxref label="_005cfbox-_0026-_005cframebox">
            <xrefnodename>
              \fbox
              &
               \framebox
            </xrefnodename>
          </pxref>
          ) or
          <code>
            \frame
          </code>
           (
          <pxref label="_005cframe">
            <xrefnodename>
              \frame
            </xrefnodename>
          </pxref>
          ).
        </para>
      </subsection>
      <node name="_005cframe" spaces=" ">
        <nodename>
          \frame
        </nodename>
        <nodenext automatic="on">
          \dashbox
        </nodenext>
        <nodeprev automatic="on">
          \framebox (picture)
        </nodeprev>
        <nodeup automatic="on">
          picture
        </nodeup>
      </node>
      <subsection spaces=" ">
        <sectiontitle>
          <code>
            \frame
          </code>
        </sectiontitle>
        <findex index="fn" spaces=" ">
          <indexterm index="fn" number="391" mergedindex="cp">
            \frame
          </indexterm>
        </findex>
        <para>
          Synopsis:
        </para>
        <example endspaces=" ">
          <pre xml:space="preserve">
            \frame
Default handler: &lbrace;
            <var>
              contents
            </var>
Default handler: &rbrace;
          </pre>
        </example>
        <para>
          Puts a rectangular frame around
          <var>
            contents
          </var>
          . The reference point is the bottom left corner of the frame. In contrast to
          <code>
            \framebox
          </code>
           (
          <pxref label="_005cframebox-_0028picture_0029">
            <xrefnodename>
              \framebox (picture)
            </xrefnodename>
          </pxref>
          ), this command puts no extra space between the frame and the object. It is fragile (
          <pxref label="_005cprotect">
            <xrefnodename>
              \protect
            </xrefnodename>
          </pxref>
          ).
        </para>
      </subsection>
      <node name="_005cdashbox" spaces=" ">
        <nodename>
          \dashbox
        </nodename>
        <nodeprev automatic="on">
          \frame
        </nodeprev>
        <nodeup automatic="on">
          picture
        </nodeup>
      </node>
      <subsection spaces=" ">
        <sectiontitle>
          <code>
            \dashbox
          </code>
        </sectiontitle>
        <findex index="fn" spaces=" ">
          <indexterm index="fn" number="392" mergedindex="cp">
            \dashbox
          </indexterm>
        </findex>
        <para>
          Synopsis:
        </para>
        <example endspaces=" ">
          <pre xml:space="preserve">
            \dashbox
Default handler: &lbrace;
            <var>
              dash-len
            </var>
Default handler: &rbrace;
            (
            <var>
              rect-width
            </var>
            ,
            <var>
              rect-height
            </var>
            )
Default handler: &lbrace;
            <var>
              text
            </var>
Default handler: &rbrace;
             \dashbox
Default handler: &lbrace;
            <var>
              dash-len
            </var>
Default handler: &rbrace;
            (
            <var>
              rect-width
            </var>
            ,
            <var>
              rect-height
            </var>
            )[
            <var>
              position
            </var>
            ]
Default handler: &lbrace;
            <var>
              text
            </var>
Default handler: &rbrace;
          </pre>
        </example>
        <para>
          Create a dashed rectangle around
          <var>
            text
          </var>
          . This command fits with the
          <code>
            picture
          </code>
           environment, although you can use it outside of there, because lengths are numbers specifying the distance in terms of the
          <code>
            \unitlength
          </code>
           (
          <pxref label="picture">
            <xrefnodename>
              picture
            </xrefnodename>
          </pxref>
          ).
        </para>
        <para>
          The required arguments are: dashes are
          <var>
            dash-len
          </var>
           units long, with the same length gap, and the rectangle has overall width
          <var>
            rect-width
          </var>
           units and height
          <var>
            rect-height
          </var>
           units.
        </para>
        <para>
          The optional argument
          <var>
            position
          </var>
           specifies the position of
          <var>
            text
          </var>
          ; see
          <ref label="_005cmakebox-_0028picture_0029">
            <xrefnodename>
              \makebox (picture)
            </xrefnodename>
          </ref>
           for the values that it can take.
        </para>
        <para>
          This shows that you can use non-integer value for
          <var>
            dash-len
          </var>
          .
        </para>
        <example endspaces=" ">
          <pre xml:space="preserve">
            \put(0,0)
Default handler: &lbrace;
            \dashbox
Default handler: &lbrace;
            0.1
Default handler: &rbrace;
            (5,0.5)
Default handler: &lbrace;
            My hovercraft is full of eels.
Default handler: &rbrace;
Default handler: &rbrace;
          </pre>
        </example>
        <noindent/>
        <para>
          Each dash will be
          <code>
            0.1\unitlength
          </code>
           long, the box
Default handler: &textrsquo;
          s width is
          <code>
            5\unitlength
          </code>
           and its height is
          <code>
            0.5\unitlength
          </code>
          .
        </para>
        <para>
          As in that example, a dashed box looks best when
          <var>
            rect-width
          </var>
           and
          <var>
            rect-height
          </var>
           are multiples of the
          <var>
            dash-len
          </var>
          .
        </para>
      </subsection>
    </section>
    <node name="quotation-_0026-quote" spaces=" ">
      <nodename>
        quotation
        &
         quote
      </nodename>
      <nodenext automatic="on">
        tabbing
      </nodenext>
      <nodeprev automatic="on">
        picture
      </nodeprev>
      <nodeup automatic="on">
        Environments
      </nodeup>
    </node>
    <section spaces=" ">
      <sectiontitle>
        <code>
          quotation
        </code>
        &
        <code>
          quote
        </code>
      </sectiontitle>
      <anchor name="quotation">
        quotation
      </anchor>
      <findex index="fn" spaces=" ">
        <indexterm index="fn" number="393" mergedindex="cp">
          <r>
            environment
          </r>
          ,
          <code>
            quotation
          </code>
        </indexterm>
      </findex>
      <findex index="fn" spaces=" ">
        <indexterm index="fn" number="394" mergedindex="cp">
          <code>
            quotation
          </code>
          <r>
            environment
          </r>
        </indexterm>
      </findex>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="392">
          quoted text with paragraph indentation, displaying
        </indexterm>
      </cindex>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="393">
          displaying quoted text with paragraph indentation
        </indexterm>
      </cindex>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="394">
          paragraph indentations in quoted text
        </indexterm>
      </cindex>
      <anchor name="quote">
        quote
      </anchor>
      <findex index="fn" spaces=" ">
        <indexterm index="fn" number="395" mergedindex="cp">
          <r>
            environment
          </r>
          ,
          <code>
            quote
          </code>
        </indexterm>
      </findex>
      <findex index="fn" spaces=" ">
        <indexterm index="fn" number="396" mergedindex="cp">
          <code>
            quote
          </code>
          <r>
            environment
          </r>
        </indexterm>
      </findex>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="395">
          quoted text without paragraph indentation, displaying
        </indexterm>
      </cindex>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="396">
          displaying quoted text without paragraph indentation
        </indexterm>
      </cindex>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="397">
          paragraph indentations in quoted text, omitting
        </indexterm>
      </cindex>
      <para>
        Synopsis:
      </para>
      <example endspaces=" ">
        <pre xml:space="preserve">
          \begin
Default handler: &lbrace;
          quotation
Default handler: &rbrace;
          <var>
            text
          </var>
           \end
Default handler: &lbrace;
          quotation
Default handler: &rbrace;
        </pre>
      </example>
      <noindent/>
      <para>
        or
      </para>
      <example endspaces=" ">
        <pre xml:space="preserve">
          \begin
Default handler: &lbrace;
          quote
Default handler: &rbrace;
          <var>
            text
          </var>
           \end
Default handler: &lbrace;
          quote
Default handler: &rbrace;
        </pre>
      </example>
      <para>
        Include a quotation. Both environments indent margins on both sides by
        <code>
          \leftmargin
        </code>
         and the text is right-justified.
      </para>
      <para>
        They differ in how they treat paragraphs. In the
        <code>
          quotation
        </code>
         environment, paragraphs are indented by 1.5
        <dmn>
          em
        </dmn>
         and the space between paragraphs is small,
        <code>
          0pt plus 1pt
        </code>
        . In the
        <code>
          quote
        </code>
         environment, paragraphs are not indented and there is vertical space between paragraphs (it is the rubber length
        <code>
          \parsep
        </code>
        ).
      </para>
      <example endspaces=" ">
        <pre xml:space="preserve">
          \begin
Default handler: &lbrace;
          quotation
Default handler: &rbrace;
           \small\it Four score and seven years ago ... shall not perish from the earth. \hspace
Default handler: &lbrace;
          1em plus 1fill
Default handler: &rbrace;
          ---Abraham Lincoln \end
Default handler: &lbrace;
          quotation
Default handler: &rbrace;
        </pre>
      </example>
    </section>
    <node name="tabbing" spaces=" ">
      <nodename>
        tabbing
      </nodename>
      <nodenext automatic="on">
        table
      </nodenext>
      <nodeprev automatic="on">
        quotation
        &
         quote
      </nodeprev>
      <nodeup automatic="on">
        Environments
      </nodeup>
    </node>
    <section spaces=" ">
      <sectiontitle>
        <code>
          tabbing
        </code>
      </sectiontitle>
Default handler: <!-- c xx TODO align on the French which is more precise and has more illustrative examples. -->
      <findex index="fn" spaces=" ">
        <indexterm index="fn" number="397" mergedindex="cp">
          <r>
            environment
          </r>
          ,
          <code>
            tabbing
          </code>
        </indexterm>
      </findex>
      <findex index="fn" spaces=" ">
        <indexterm index="fn" number="398" mergedindex="cp">
          <code>
            tabbing
          </code>
          <r>
            environment
          </r>
        </indexterm>
      </findex>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="398">
          tab stops, using
        </indexterm>
      </cindex>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="399">
          lining text up using tab stops
        </indexterm>
      </cindex>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="400">
          alignment via tabbing
        </indexterm>
      </cindex>
      <para>
        Synopsis:
      </para>
      <example endspaces=" ">
        <pre xml:space="preserve">
          \begin
Default handler: &lbrace;
          tabbing
Default handler: &rbrace;
          <var>
            row1col1
          </var>
           \=
          <var>
            row1col2
          </var>
           ... \\
          <var>
            row2col1
          </var>
           \
          >
          <var>
            row2col2
          </var>
           ... \\ ... \end
Default handler: &lbrace;
          tabbing
Default handler: &rbrace;
        </pre>
      </example>
      <para>
        Align text in columns, by setting tab stops and tabbing to them much as was done on a typewriter. This is less often used than the environments
        <code>
          tabular
        </code>
         (
        <pxref label="tabular">
          <xrefnodename>
            tabular
          </xrefnodename>
        </pxref>
        ) or
        <code>
          array
        </code>
         (
        <pxref label="array">
          <xrefnodename>
            array
          </xrefnodename>
        </pxref>
        ) because in those the width of each column need not be constant and need not be known in advance.
      </para>
      <para>
        This example has a first line where the tab stops are set to explicit widths, ended by a
        <code>
          \kill
        </code>
         command (which is described below):
      </para>
      <example endspaces=" ">
        <pre xml:space="preserve">
          \begin
Default handler: &lbrace;
          tabbing
Default handler: &rbrace;
           \hspace
Default handler: &lbrace;
          1.2in
Default handler: &rbrace;
          \=\hspace
Default handler: &lbrace;
          1in
Default handler: &rbrace;
          \=\kill Ship \
          >
          Guns \
          >
          Year \\ \textit
Default handler: &lbrace;
          Sophie
Default handler: &rbrace;
           \
          >
          14 \
          >
          1800 \\ \textit
Default handler: &lbrace;
          Polychrest
Default handler: &rbrace;
           \
          >
          24 \
          >
          1803 \\ \textit
Default handler: &lbrace;
          Lively
Default handler: &rbrace;
           \
          >
          38 \
          >
          1804 \\ \textit
Default handler: &lbrace;
          Surprise
Default handler: &rbrace;
           \
          >
          28 \
          >
          1805 \\ \end
Default handler: &lbrace;
          tabbing
Default handler: &rbrace;
        </pre>
      </example>
      <para>
        Both the
        <code>
          tabbing
        </code>
         environment and the more widely-used
        <code>
          tabular
        </code>
         environment put text in columns. The most important distinction is that in
        <code>
          tabular
        </code>
         the width of columns is determined automatically by
Default handler: &latex;
        , while in
        <code>
          tabbing
        </code>
         the user sets the tab stops. Another distinction is that
        <code>
          tabular
        </code>
         generates a box, but
        <code>
          tabbing
        </code>
         can be broken across pages. Finally, while
        <code>
          tabular
        </code>
         can be used in any mode,
        <code>
          tabbing
        </code>
         can be used only in paragraph mode and it always starts a new paragraph, without indentation.
      </para>
      <para>
        Moreover, as shown in the example above, there is no need to use the starred form of the
        <code>
          \hspace
        </code>
         command at the beginning of a tabbed row. The right margin of the
        <code>
          tabbing
        </code>
         environment is the end of line, so that the width of the environment is
        <code>
          \linewidth
        </code>
        .
      </para>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="401">
          row,
          <r>
            tabbing
          </r>
        </indexterm>
      </cindex>
      <para>
        The
        <code>
          tabbing
        </code>
         environment contains a sequence of
        <dfn>
          tabbed rows
        </dfn>
        . The first tabbed row begins immediately after
        <code>
          \begin
Default handler: &lbrace;
          tabbing
Default handler: &rbrace;
        </code>
         and each row ends with
        <code>
          \\
        </code>
         or
        <code>
          \kill
        </code>
        . The last row may omit the
        <code>
          \\
        </code>
         and end with just
        <code>
          \end
Default handler: &lbrace;
          tabbing
Default handler: &rbrace;
        </code>
        .
      </para>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="402">
          pattern, current tab stops,
          <r>
            tabbing
          </r>
        </indexterm>
      </cindex>
      <para>
        At any point the
        <code>
          tabbing
        </code>
         environment has a
        <dfn>
          current tab stop pattern
        </dfn>
        , a sequence of
        <math>
          <var>
            n
          </var>
          >
           0
        </math>
         tab stops, numbered 0, 1, etc. These create
        <var>
          n
        </var>
         corresponding columns. Tab stop
Default handler: &nbsp;
        0 is always the left margin, defined by the enclosing environment. Tab stop number
Default handler: &nbsp;
        <var>
          i
        </var>
         is set if it is assigned a horizontal position on the page. Tab stop number
Default handler: &nbsp;
        <var>
          i
        </var>
         can only be set if all the stops 0,
Default handler: &dots;
        ,
        <math>
          i-1
        </math>
         have already been set; normally later stops are to the right of earlier ones.
      </para>
      <para>
        By default any text typeset in a
        <code>
          tabbing
        </code>
         environment is typeset ragged right and left-aligned on the current tab stop. Typesetting is done in LR mode (
        <pxref label="Modes">
          <xrefnodename>
            Modes
          </xrefnodename>
        </pxref>
        ).
      </para>
      <para>
        The following commands can be used inside a
        <code>
          tabbing
        </code>
         environment. They are all fragile (
        <pxref label="_005cprotect">
          <xrefnodename>
            \protect
          </xrefnodename>
        </pxref>
        ).
      </para>
      <ftable commandarg="code" spaces=" " endspaces=" ">
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                <indexterm index="fn" number="399" mergedindex="cp">
                  \\
                  <r>
                    (tabbing)
                  </r>
                </indexterm>
                \\
                <r>
                  (tabbing)
                </r>
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <para>
              End a tabbed line and typeset it.
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                <indexterm index="fn" number="400" mergedindex="cp">
                  \=
                  <r>
                    (tabbing)
                  </r>
                </indexterm>
                \=
                <r>
                  (tabbing)
                </r>
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <para>
              Sets a tab stop at the current position.
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                <indexterm index="fn" number="401" mergedindex="cp">
                  \
                  >
                  <r>
                    (tabbing)
                  </r>
                </indexterm>
                \
                >
                <r>
                  (tabbing)
                </r>
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <findex index="fn" spaces=" ">
              <indexterm index="fn" number="402" mergedindex="cp">
                \
                >
              </indexterm>
            </findex>
            <para>
              Advances to the next tab stop.
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                <indexterm index="fn" number="403" mergedindex="cp">
                  \
                  <
                </indexterm>
                \
                <
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <para>
              Put following text to the left of the local margin (without changing the margin). Can only be used at the start of the line.
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                <indexterm index="fn" number="404" mergedindex="cp">
                  \+
                </indexterm>
                \+
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <para>
              Moves the left margin of the next and all the following commands one tab stop to the right, beginning tabbed line if necessary.
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                <indexterm index="fn" number="405" mergedindex="cp">
                  \-
                </indexterm>
                \-
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <para>
              Moves the left margin of the next and all the following commands one tab stop to the left, beginning tabbed line if necessary.
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                <indexterm index="fn" number="406" mergedindex="cp">
                  \'
                  <r>
                    (tabbing)
                  </r>
                </indexterm>
                \'
                <r>
                  (tabbing)
                </r>
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <para>
              Moves everything that you have typed so far in the current column, i.e., everything from the most recent
              <code>
                \
                >
              </code>
              ,
              <code>
                \
                <
              </code>
              ,
              <code>
                \'
              </code>
              ,
              <code>
                \\
              </code>
              , or
              <code>
                \kill
              </code>
               command, to the previous column and aligned to the right, flush against the current column
Default handler: &textrsquo;
              s tab stop.
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                <indexterm index="fn" number="407" mergedindex="cp">
                  \`
                  <r>
                    (tabbing)
                  </r>
                </indexterm>
                \`
                <r>
                  (tabbing)
                </r>
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <para>
              Allows you to put text flush right against any tab stop, including tab stop
Default handler: &nbsp;
              0. However, it can
Default handler: &textrsquo;
              t move text to the right of the last column because there
Default handler: &textrsquo;
              s no tab stop there. The
              <code>
                \`
              </code>
               command moves all the text that follows it, up to the
              <code>
                \\
              </code>
               or
              <code>
                \end
Default handler: &lbrace;
                tabbing
Default handler: &rbrace;
              </code>
               command that ends the line, to the right margin of the
              <code>
                tabbing
              </code>
               environment. There must be no
              <code>
                \
                >
              </code>
               or
              <code>
                \'
              </code>
               command between the
              <code>
                \`
              </code>
               and the
              <code>
                \\
              </code>
               or
              <code>
                \end
Default handler: &lbrace;
                tabbing
Default handler: &rbrace;
              </code>
               command that ends the line.
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                <indexterm index="fn" number="408" mergedindex="cp">
                  \a
                  <r>
                    (tabbing)
                  </r>
                </indexterm>
                \a
                <r>
                  (tabbing)
                </r>
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <findex index="fn" spaces=" ">
              <indexterm index="fn" number="409" mergedindex="cp">
                \a'
                <r>
                  (acute accent in tabbing)
                </r>
              </indexterm>
            </findex>
            <findex index="fn" spaces=" ">
              <indexterm index="fn" number="410" mergedindex="cp">
                \a`
                <r>
                  (grave accent in tabbing)
                </r>
              </indexterm>
            </findex>
            <findex index="fn" spaces=" ">
              <indexterm index="fn" number="411" mergedindex="cp">
                \a=
                <r>
                  (macron accent in tabbing)
                </r>
              </indexterm>
            </findex>
            <para>
              In a
              <code>
                tabbing
              </code>
               environment, the commands
              <code>
                \=
              </code>
              ,
              <code>
                \'
              </code>
               and
              <code>
                \`
              </code>
               do not produce accents as usual (
              <pxref label="Accents">
                <xrefnodename>
                  Accents
                </xrefnodename>
              </pxref>
              ). Instead, use the commands
              <code>
                \a=
              </code>
              ,
              <code>
                \a'
              </code>
               and
              <code>
                \a`
              </code>
              .
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                <indexterm index="fn" number="412" mergedindex="cp">
                  \kill
                </indexterm>
                \kill
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <para>
              Sets tab stops without producing text. Works just like
              <code>
                \\
              </code>
               except that it throws away the current line instead of producing output for it. Any
              <code>
                \=
              </code>
              ,
              <code>
                \+
              </code>
               or
              <code>
                \-
              </code>
               commands in that line remain in effect.
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                <indexterm index="fn" number="413" mergedindex="cp">
                  \poptabs
                </indexterm>
                \poptabs
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <findex index="fn" spaces=" ">
              <indexterm index="fn" number="414" mergedindex="cp">
                \poptabs
              </indexterm>
            </findex>
            <para>
              Restores the tab stop positions saved by the last
              <code>
                \pushtabs
              </code>
              .
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                <indexterm index="fn" number="415" mergedindex="cp">
                  \pushtabs
                </indexterm>
                \pushtabs
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <para>
              Saves all current tab stop positions. Useful for temporarily changing tab stop positions in the middle of a
              <code>
                tabbing
              </code>
               environment.
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                <indexterm index="fn" number="416" mergedindex="cp">
                  \tabbingsep
                </indexterm>
                \tabbingsep
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <para>
              Distance of the text moved by
              <code>
                \'
              </code>
               to left of current tab stop.
            </para>
          </tableitem>
        </tableentry>
      </ftable>
      <para>
        This example typesets a Pascal function:
      </para>
      <example endspaces=" ">
        <pre xml:space="preserve">
          \begin
Default handler: &lbrace;
          tabbing
Default handler: &rbrace;
           function \= fact(n : integer) : integer;\\ \
          >
           begin \= \+ \\ \
          >
           if \= n
          >
           1 then \+ \\ fact := n * fact(n-1) \- \\ else \+ \\ fact := 1; \-\- \\ end;\\ \end
Default handler: &lbrace;
          tabbing
Default handler: &rbrace;
        </pre>
      </example>
      <noindent/>
      <para>
        The output looks like this.
      </para>
      <example endspaces=" ">
        <pre xml:space="preserve">
          function fact(n : integer) : integer; begin if n
          >
           1 then fact := n * fact(n-1); else fact := 1; end;
        </pre>
      </example>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="403">
          <r>
            package
          </r>
          ,
          <code>
            algorithm2e
          </code>
        </indexterm>
      </cindex>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="404">
          <code>
            algorithm2e
          </code>
          <r>
            package
          </r>
        </indexterm>
      </cindex>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="405">
          <r>
            package
          </r>
          ,
          <code>
            fancyvrb
          </code>
        </indexterm>
      </cindex>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="406">
          <code>
            fancyvrb
          </code>
          <r>
            package
          </r>
        </indexterm>
      </cindex>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="407">
          <r>
            package
          </r>
          ,
          <code>
            listings
          </code>
        </indexterm>
      </cindex>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="408">
          <code>
            listings
          </code>
          <r>
            package
          </r>
        </indexterm>
      </cindex>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="409">
          <r>
            package
          </r>
          ,
          <code>
            minted
          </code>
        </indexterm>
      </cindex>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="410">
          <code>
            minted
          </code>
          <r>
            package
          </r>
        </indexterm>
      </cindex>
      <noindent/>
      <para>
        This example is just for illustration of the environment. To actually typeset computer code in typewriter like this, a verbatim environment (
        <pxref label="verbatim">
          <xrefnodename>
            verbatim
          </xrefnodename>
        </pxref>
        ) would normally be best. For pretty-printed code, there are quite a few packages, including
        <code>
          algorithm2e
        </code>
        ,
        <code>
          fancyvrb
        </code>
        ,
        <code>
          listings
        </code>
        , and
        <code>
          minted
        </code>
        .
      </para>
    </section>
    <node name="table" spaces=" ">
      <nodename>
        table
      </nodename>
      <nodenext automatic="on">
        tabular
      </nodenext>
      <nodeprev automatic="on">
        tabbing
      </nodeprev>
      <nodeup automatic="on">
        Environments
      </nodeup>
    </node>
    <section spaces=" ">
      <sectiontitle>
        <code>
          table
        </code>
      </sectiontitle>
      <findex index="fn" spaces=" ">
        <indexterm index="fn" number="417" mergedindex="cp">
          <r>
            environment
          </r>
          ,
          <code>
            table
          </code>
        </indexterm>
      </findex>
      <findex index="fn" spaces=" ">
        <indexterm index="fn" number="418" mergedindex="cp">
          <code>
            table
          </code>
          <r>
            environment
          </r>
        </indexterm>
      </findex>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="411">
          tables, creating
        </indexterm>
      </cindex>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="412">
          creating tables
        </indexterm>
      </cindex>
      <para>
        Synopsis:
      </para>
      <example endspaces=" ">
        <pre xml:space="preserve">
          \begin
Default handler: &lbrace;
          table
Default handler: &rbrace;
          [
          <var>
            placement
          </var>
          ]
          <var>
            table body
          </var>
           \caption[
          <var>
            loftitle
          </var>
          ]
Default handler: &lbrace;
          <var>
            title
          </var>
Default handler: &rbrace;
           % optional \label
Default handler: &lbrace;
          <var>
            label
Default handler: &rbrace;
          </var>
           % also optional \end
Default handler: &lbrace;
          table
Default handler: &rbrace;
        </pre>
      </example>
      <para>
        A class of floats (
        <pxref label="Floats">
          <xrefnodename>
            Floats
          </xrefnodename>
        </pxref>
        ). They cannot be split across pages and so they are not typeset in sequence with the normal text but instead are floated to a convenient place, such as the top of a following page.
      </para>
      <para>
        This example
        <code>
          table
        </code>
         environment contains a
        <code>
          tabular
        </code>
      </para>
      <example endspaces=" ">
        <pre xml:space="preserve">
          \begin
Default handler: &lbrace;
          table
Default handler: &rbrace;
           \centering\small \begin
Default handler: &lbrace;
          tabular
Default handler: &rbrace;
Default handler: &lbrace;
          ll
Default handler: &rbrace;
           \multicolumn
Default handler: &lbrace;
          1
Default handler: &rbrace;
Default handler: &lbrace;
          c
Default handler: &rbrace;
Default handler: &lbrace;
          \textit
Default handler: &lbrace;
          Author
Default handler: &rbrace;
Default handler: &rbrace;
          &
          \multicolumn
Default handler: &lbrace;
          1
Default handler: &rbrace;
Default handler: &lbrace;
          c
Default handler: &rbrace;
Default handler: &lbrace;
          \textit
Default handler: &lbrace;
          Piece
Default handler: &rbrace;
Default handler: &rbrace;
           \\ \hline Bach
          &
          Cello Suite Number 1 \\ Beethoven
          &
          Cello Sonata Number 3 \\ Brahms
          &
          Cello Sonata Number 1 \end
Default handler: &lbrace;
          tabular
Default handler: &rbrace;
           \caption
Default handler: &lbrace;
          Top cello pieces
Default handler: &rbrace;
           \label
Default handler: &lbrace;
          tab:cello
Default handler: &rbrace;
           \end
Default handler: &lbrace;
          table
Default handler: &rbrace;
        </pre>
      </example>
      <noindent/>
      <para>
        but you can put many different kinds of content in a
        <code>
          table
        </code>
        : the
        <var>
          table body
        </var>
         may contain text,
Default handler: &latex;
         commands, graphics, etc. It is typeset in a
        <code>
          parbox
        </code>
         of width
        <code>
          \textwidth
        </code>
        .
      </para>
      <para>
        For the possible values of
        <var>
          placement
        </var>
         and their effect on the float placement algorithm, see
        <ref label="Floats">
          <xrefnodename>
            Floats
          </xrefnodename>
        </ref>
        .
      </para>
      <para>
        The label is optional; it is used for cross references (
        <pxref label="Cross-references">
          <xrefnodename>
            Cross references
          </xrefnodename>
        </pxref>
        ).
        <findex index="fn" spaces=" ">
          <indexterm index="fn" number="419" mergedindex="cp">
            \caption
          </indexterm>
        </findex>
         The
        <code>
          \caption
        </code>
         command is also optional. It specifies caption text
        <var>
          title
        </var>
         for the table (
        <pxref label="_005ccaption">
          <xrefnodename>
            \caption
          </xrefnodename>
        </pxref>
        ). By default it is numbered. If its optional
        <var>
          lottitle
        </var>
         is present then that text is used in the list of tables instead of
        <var>
          title
        </var>
         (
        <pxref label="Table-of-contents-etc_002e">
          <xrefnodename>
            Table of contents etc.
          </xrefnodename>
        </pxref>
        ).
      </para>
      <para>
        In this example the table and caption will float to the bottom of a page, unless it is pushed to a float page at the end.
      </para>
      <example endspaces=" ">
        <pre xml:space="preserve">
          \begin
Default handler: &lbrace;
          table
Default handler: &rbrace;
          [b] \centering \begin
Default handler: &lbrace;
          tabular
Default handler: &rbrace;
Default handler: &lbrace;
          r|p
Default handler: &lbrace;
          2in
Default handler: &rbrace;
Default handler: &rbrace;
           \hline One
          &
          The loneliest number \\ Two
          &
          Can be as sad as one. It's the loneliest number since the number one. \end
Default handler: &lbrace;
          tabular
Default handler: &rbrace;
           \caption
Default handler: &lbrace;
          Cardinal virtues
Default handler: &rbrace;
           \label
Default handler: &lbrace;
          tab:CardinalVirtues
Default handler: &rbrace;
           \end
Default handler: &lbrace;
          table
Default handler: &rbrace;
        </pre>
      </example>
    </section>
    <node name="tabular" spaces=" ">
      <nodename>
        tabular
      </nodename>
      <nodenext automatic="on">
        thebibliography
      </nodenext>
      <nodeprev automatic="on">
        table
      </nodeprev>
      <nodeup automatic="on">
        Environments
      </nodeup>
    </node>
    <section spaces=" ">
      <sectiontitle>
        <code>
          tabular
        </code>
      </sectiontitle>
      <findex index="fn" spaces=" ">
        <indexterm index="fn" number="420" mergedindex="cp">
          <r>
            environment
          </r>
          ,
          <code>
            tabular
          </code>
        </indexterm>
      </findex>
      <findex index="fn" spaces=" ">
        <indexterm index="fn" number="421" mergedindex="cp">
          <code>
            tabular
          </code>
          <r>
            environment
          </r>
        </indexterm>
      </findex>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="413">
          lines in tables
        </indexterm>
      </cindex>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="414">
          lining text up in tables
        </indexterm>
      </cindex>
      <para>
        Synopsis:
      </para>
      <example endspaces=" ">
        <pre xml:space="preserve">
          \begin
Default handler: &lbrace;
          tabular
Default handler: &rbrace;
          [
          <var>
            pos
          </var>
          ]
Default handler: &lbrace;
          <var>
            cols
          </var>
Default handler: &rbrace;
          <var>
            column 1 entry
          </var>
          &
          <var>
            column 2 entry
          </var>
           ...
          &
          <var>
            column n entry
          </var>
           \\ ... \end
Default handler: &lbrace;
          tabular
Default handler: &rbrace;
        </pre>
      </example>
      <noindent/>
      <para>
        or
      </para>
      <example endspaces=" ">
        <pre xml:space="preserve">
          \begin
Default handler: &lbrace;
          tabular*
Default handler: &rbrace;
Default handler: &lbrace;
          <var>
            width
          </var>
Default handler: &rbrace;
          [
          <var>
            pos
          </var>
          ]
Default handler: &lbrace;
          <var>
            cols
          </var>
Default handler: &rbrace;
          <var>
            column 1 entry
          </var>
          &
          <var>
            column 2 entry
          </var>
           ...
          &
          <var>
            column n entry
          </var>
           \\ ... \end
Default handler: &lbrace;
          tabular*
Default handler: &rbrace;
        </pre>
      </example>
      <para>
        Produce a table, a box consisting of a sequence of horizontal rows. Each row consists of items that are aligned vertically in columns. This illustrates many of the features.
      </para>
      <example endspaces=" ">
        <pre xml:space="preserve">
          \begin
Default handler: &lbrace;
          tabular
Default handler: &rbrace;
Default handler: &lbrace;
          l|l
Default handler: &rbrace;
           \textit
Default handler: &lbrace;
          Player name
Default handler: &rbrace;
          &
          \textit
Default handler: &lbrace;
          Career home runs
Default handler: &rbrace;
           \\ \hline Hank Aaron
          &
          755 \\ Babe Ruth
          &
          714 \end
Default handler: &lbrace;
          tabular
Default handler: &rbrace;
        </pre>
      </example>
      <noindent/>
      <para>
        The output will have two left-aligned columns with a vertical bar between them. This is specified in
        <code>
          tabular
        </code>
Default handler: &textrsquo;
        s argument
        <codeDefault handler: &lbrace;
>
          l|l
Default handler: &rbrace;
        </code>
        .
        <findex index="fn" spaces=" ">
          <indexterm index="fn" number="422" mergedindex="cp">
            &
            <r>
              (for table cells)
            </r>
          </indexterm>
        </findex>
         Put the entries into different columns by separating them with an ampersand,
        <code>
          &
        </code>
        . The end of each row is marked with a double backslash,
        <code>
          \\
        </code>
        . Put a horizontal rule below a row, after a double backslash, with
        <code>
          \hline
        </code>
        .
        <findex index="fn" spaces=" ">
          <indexterm index="fn" number="423" mergedindex="cp">
            \\
            <r>
              (for
              <code>
                tabular
              </code>
              )
            </r>
          </indexterm>
        </findex>
         After the last row the
        <code>
          \\
        </code>
         is optional, unless an
        <code>
          \hline
        </code>
         command follows to put a rule below the table.
      </para>
      <para>
        The required and optional arguments to
        <code>
          tabular
        </code>
         consist of:
      </para>
      <table commandarg="var" spaces=" " endspaces=" ">
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="var">
                pos
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <para>
              Optional. Specifies the table
Default handler: &textrsquo;
              s vertical position. The default is to align the table so its vertical center matches the baseline of the surrounding text. There are two other possible alignments:
              <code>
                t
              </code>
               aligns the table so its top row matches the baseline of the surrounding text, and
              <code>
                b
              </code>
               aligns on the bottom row.
            </para>
            <para>
              This only has an effect if there is other text. In the common case of a
              <code>
                tabular
              </code>
               alone in a
              <code>
                center
              </code>
               environment this option makes no difference.
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="var">
                cols
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <para>
              Required. Specifies the formatting of columns. It consists of a sequence of the following specifiers, corresponding to the types of column and intercolumn material.
            </para>
            <table commandarg="code" spaces=" " endspaces=" ">
              <tableentry>
                <tableterm>
                  <item spaces=" ">
                    <itemformat command="code">
                      l
                    </itemformat>
                  </item>
                </tableterm>
                <tableitem>
                  <para>
                    A column of left-aligned items.
                  </para>
                </tableitem>
              </tableentry>
              <tableentry>
                <tableterm>
                  <item spaces=" ">
                    <itemformat command="code">
                      r
                    </itemformat>
                  </item>
                </tableterm>
                <tableitem>
                  <para>
                    A column of right-aligned items.
                  </para>
                </tableitem>
              </tableentry>
              <tableentry>
                <tableterm>
                  <item spaces=" ">
                    <itemformat command="code">
                      c
                    </itemformat>
                  </item>
                </tableterm>
                <tableitem>
                  <para>
                    A column of centered items.
                  </para>
                </tableitem>
              </tableentry>
              <tableentry>
                <tableterm>
                  <item spaces=" ">
                    <itemformat command="code">
                      |
                    </itemformat>
                  </item>
                </tableterm>
                <tableitem>
                  <para>
                    A vertical line the full height and depth of the environment.
                  </para>
                </tableitem>
              </tableentry>
              <tableentry>
                <tableterm>
                  <item spaces=" ">
                    <itemformat command="code"Default handler: &arobase;
Default handler: &lbrace;
>
                      <var>
                        text or space
                      </var>
Default handler: &rbrace;
                    </itemformat>
                  </item>
                </tableterm>
                <tableitem>
                  <para>
                    Insert
                    <var>
                      text or space
                    </var>
                     at this location in every row. The
                    <var>
                      text or space
                    </var>
                     material is typeset in LR mode. This text is fragile (
                    <pxref label="_005cprotect">
                      <xrefnodename>
                        \protect
                      </xrefnodename>
                    </pxref>
                    ).
                  </para>
                  <para>
                    If between two column specifiers there is no
Default handler: &arobase;
                    -expression then
Default handler: &latex;
Default handler: &textrsquo;
                    s
                    <code>
                      book
                    </code>
                    ,
                    <code>
                      article
                    </code>
                    , and
                    <code>
                      report
                    </code>
                     classes will put on either side of each column a space of width
                    <code>
                      \tabcolsep
                    </code>
                    , which by default is 6
                    <dmn>
                      pt
                    </dmn>
                    . That is, by default adjacent columns are separated by 12
                    <dmn>
                      pt
                    </dmn>
                     (so
                    <code>
                      \tabcolsep
                    </code>
                     is misleadingly named since it is only half of the separation between tabular columns). In addition, a space of
                    <code>
                      \tabcolsep
                    </code>
                     also comes before the first column and after the final column, unless you put a
                    <codeDefault handler: &arobase;
Default handler: &lbrace;
>
                      ...
Default handler: &rbrace;
                    </code>
                     there.
                  </para>
                  <para>
                    If you override the default and use an
Default handler: &arobase;
                    -expression then
Default handler: &latex;
                     does not insert
                    <code>
                      \tabcolsep
                    </code>
                     so you must insert any desired space yourself, as in
                    <codeDefault handler: &arobase;
Default handler: &lbrace;
>
                      \hspace
Default handler: &lbrace;
                      1em
Default handler: &rbrace;
Default handler: &rbrace;
                    </code>
                    .
                  </para>
                  <para>
                    An empty expression
                    <codeDefault handler: &arobase;
Default handler: &lbrace;
Default handler: &rbrace;
/>
                     will eliminate the space. In particular, sometimes you want to eliminate the space before the first column or after the last one, as in the example below where the tabular lines need to lie on the left margin.
                  </para>
                  <example endspaces=" ">
                    <pre xml:space="preserve">
                      \begin
Default handler: &lbrace;
                      flushleft
Default handler: &rbrace;
                       \begin
Default handler: &lbrace;
                      tabular
Default handler: &rbrace;
Default handler: &lbrace;
Default handler: &arobase;
Default handler: &lbrace;
Default handler: &rbrace;
                      l
Default handler: &rbrace;
                       ... \end
Default handler: &lbrace;
                      tabular
Default handler: &rbrace;
                       \end
Default handler: &lbrace;
                      flushleft
Default handler: &rbrace;
                    </pre>
                  </example>
                  <para>
                    The next example shows text, a decimal point between the columns, arranged so the numbers in the table are aligned on it.
                  </para>
                  <example endspaces=" ">
                    <pre xml:space="preserve">
                      \begin
Default handler: &lbrace;
                      tabular
Default handler: &rbrace;
Default handler: &lbrace;
                      r
Default handler: &arobase;
Default handler: &lbrace;
                      $.$
Default handler: &rbrace;
                      l
Default handler: &rbrace;
                       $3$
                      &
                      $14$ \\ $9$
                      &
                      $80665$ \end
Default handler: &lbrace;
                      tabular
Default handler: &rbrace;
                    </pre>
                  </example>
                  <anchor name="_005cextracolsep">
                    \extracolsep
                  </anchor>
                  <findex index="fn" spaces=" ">
                    <indexterm index="fn" number="424" mergedindex="cp">
                      \extracolsep
                    </indexterm>
                  </findex>
                  <para>
                    An
                    <code>
                      \extracolsep
Default handler: &lbrace;
                      <var>
                        wd
                      </var>
Default handler: &rbrace;
                    </code>
                     command in an
Default handler: &arobase;
                    -expression causes an extra space of width
                    <var>
                      wd
                    </var>
                     to appear to the left of all subsequent columns, until countermanded by another
                    <code>
                      \extracolsep
                    </code>
                    . Unlike ordinary intercolumn space, this extra space is not suppressed by an
Default handler: &arobase;
                    -expression. An
                    <code>
                      \extracolsep
                    </code>
                     command can be used only in an
Default handler: &arobase;
                    -expression in the
                    <code>
                      cols
                    </code>
                     argument. Below,
Default handler: &latex;
                     inserts the right amount of intercolumn space to make the entire table 4 inches wide.
                  </para>
                  <example endspaces=" ">
                    <pre xml:space="preserve">
                      \begin
Default handler: &lbrace;
                      tabular*
Default handler: &rbrace;
Default handler: &lbrace;
                      4in
Default handler: &rbrace;
Default handler: &lbrace;
                      l
Default handler: &arobase;
Default handler: &lbrace;
                      \extracolsep
Default handler: &lbrace;
                      \fill
Default handler: &rbrace;
Default handler: &rbrace;
                      l
Default handler: &rbrace;
                       Seven times down, eight times up \ldots
                      &
                      such is life! \end
Default handler: &lbrace;
                      tabular*
Default handler: &rbrace;
                    </pre>
                  </example>
                  <para>
                    To insert commands that are automatically executed before a given column, load the
                    <code>
                      array
                    </code>
                     package and use the
                    <code>
                      >
Default handler: &lbrace;
                      ...
Default handler: &rbrace;
                    </code>
                     specifier.
Default handler: <!-- c xx should fully explain array, tabularx, and all other base packages... -->
                  </para>
                </tableitem>
              </tableentry>
              <tableentry>
                <tableterm>
                  <item spaces=" ">
                    <itemformat command="code">
                      p
Default handler: &lbrace;
                      <var>
                        wd
                      </var>
Default handler: &rbrace;
                    </itemformat>
                  </item>
                </tableterm>
                <tableitem>
                  <para>
                    Each item in the column is typeset in a parbox of width
                    <var>
                      wd
                    </var>
                    , as if it were the argument of a
                    <code>
                      \parbox[t]
Default handler: &lbrace;
                      wd
Default handler: &rbrace;
Default handler: &lbrace;
                      ...
Default handler: &rbrace;
                    </code>
                     command.
                  </para>
                  <para>
                    A line break double backslash
                    <code>
                      \\
                    </code>
                     may not appear in the item, except inside an environment like
                    <code>
                      minipage
                    </code>
                    ,
                    <code>
                      array
                    </code>
                    , or
                    <code>
                      tabular
                    </code>
                    , or inside an explicit
                    <code>
                      \parbox
                    </code>
                    , or in the scope of a
                    <code>
                      \centering
                    </code>
                    ,
                    <code>
                      \raggedright
                    </code>
                    , or
                    <code>
                      \raggedleft
                    </code>
                     declaration (when used in a
                    <code>
                      p
                    </code>
                    -column element these declarations must appear inside braces, as with
                    <codeDefault handler: &lbrace;
>
                      \centering .. \\ ..
Default handler: &rbrace;
                    </code>
                    ). Otherwise
Default handler: &latex;
                     will misinterpret the double backslash as ending the tabular row. Instead, to get a line break in there use
                    <code>
                      \newline
                    </code>
                     (
                    <pxref label="_005cnewline">
                      <xrefnodename>
                        \newline
                      </xrefnodename>
                    </pxref>
                    ).
                  </para>
                </tableitem>
              </tableentry>
              <tableentry>
                <tableterm>
                  <item spaces=" ">
                    <itemformat command="code">
                      *
Default handler: &lbrace;
                      <var>
                        num
                      </var>
Default handler: &rbrace;
Default handler: &lbrace;
                      <var>
                        cols
                      </var>
Default handler: &rbrace;
                    </itemformat>
                  </item>
                </tableterm>
                <tableitem>
                  <para>
                    Equivalent to
                    <var>
                      num
                    </var>
                     copies of
                    <var>
                      cols
                    </var>
                    , where
                    <var>
                      num
                    </var>
                     is a positive integer and
                    <var>
                      cols
                    </var>
                     is a list of specifiers. Thus the specifier
                    <code>
                      \begin
Default handler: &lbrace;
                      tabular
Default handler: &rbrace;
Default handler: &lbrace;
                      |*
Default handler: &lbrace;
                      3
Default handler: &rbrace;
Default handler: &lbrace;
                      l|r
Default handler: &rbrace;
                      |
Default handler: &rbrace;
                    </code>
                     is equivalent to the specifier
                    <code>
                      \begin
Default handler: &lbrace;
                      tabular
Default handler: &rbrace;
Default handler: &lbrace;
                      |l|rl|rl|r|
Default handler: &rbrace;
                    </code>
                    . Note that
                    <var>
                      cols
                    </var>
                     may contain another
                    <code>
                      *
                    </code>
                    -expression.
                  </para>
                </tableitem>
              </tableentry>
            </table>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="var">
                width
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <para>
              Required for
              <code>
                tabular*
              </code>
              , not allowed for
              <code>
                tabular
              </code>
              . Specifies the width of the
              <code>
                tabular*
              </code>
               environment. The space between columns should be rubber, as with
              <codeDefault handler: &arobase;
Default handler: &lbrace;
>
                \extracolsep
Default handler: &lbrace;
                \fill
Default handler: &rbrace;
Default handler: &rbrace;
              </code>
              , to allow the table to stretch or shrink to make the specified width, or else you are likely to get the
              <code>
                Underfull \hbox (badness 10000) in alignment ...
              </code>
               warning.
            </para>
          </tableitem>
        </tableentry>
      </table>
      <para>
        Parameters that control formatting:
Default handler: <!-- c xx defaults, own node (xref from array)? -->
      </para>
      <ftable commandarg="code" spaces=" " endspaces=" ">
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                <indexterm index="fn" number="425" mergedindex="cp">
                  \arrayrulewidth
                </indexterm>
                \arrayrulewidth
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <anchor name="tabular-arrayrulewidth">
              tabular arrayrulewidth
            </anchor>
            <para>
              A length that is the thickness of the rule created by
              <code>
                |
              </code>
              ,
              <code>
                \hline
              </code>
              , and
              <code>
                \vline
              </code>
               in the
              <code>
                tabular
              </code>
               and
              <code>
                array
              </code>
               environments. The default is
              <samp>
                .4pt
              </samp>
              . Change it as in
              <code>
                \setlength
Default handler: &lbrace;
                \arrayrulewidth
Default handler: &rbrace;
Default handler: &lbrace;
                0.8pt
Default handler: &rbrace;
              </code>
              .
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                <indexterm index="fn" number="426" mergedindex="cp">
                  \arraystretch
                </indexterm>
                \arraystretch
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <anchor name="tabular-arraystrech">
              tabular arraystrech
            </anchor>
            <para>
              A factor by which the spacing between rows in the
              <code>
                tabular
              </code>
               and
              <code>
                array
              </code>
               environments is multiplied. The default is
              <samp>
                1
              </samp>
              , for no scaling. Change it as
              <code>
                \renewcommand
Default handler: &lbrace;
                \arraystretch
Default handler: &rbrace;
Default handler: &lbrace;
                1.2
Default handler: &rbrace;
              </code>
              .
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                <indexterm index="fn" number="427" mergedindex="cp">
                  \doublerulesep
                </indexterm>
                \doublerulesep
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <anchor name="tabular-doublerulesep">
              tabular doublerulesep
            </anchor>
            <para>
              A length that is the distance between the vertical rules produced by the
              <code>
                ||
              </code>
               specifier. The default is
              <samp>
                2pt
              </samp>
              .
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                <indexterm index="fn" number="428" mergedindex="cp">
                  \tabcolsep
                </indexterm>
                \tabcolsep
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <anchor name="tabular-tabcolsep">
              tabular tabcolsep
            </anchor>
            <para>
              A length that is half of the space between columns. The default is
              <samp>
                6pt
              </samp>
              . Change it with
              <code>
                \setlength
              </code>
              .
            </para>
          </tableitem>
        </tableentry>
      </ftable>
      <para>
        The following commands can be used inside the body of a
        <code>
          tabular
        </code>
         environment, the first two inside an entry and the second two between lines:
      </para>
      <menu endspaces=" ">
        <menuentry>
          <menuleadingtext>
            *
          </menuleadingtext>
          <menunode>
            \multicolumn
          </menunode>
          <menuseparator>
            ::
          </menuseparator>
          <menudescription>
            <pre xml:space="preserve">
              Make an item spanning several columns.
            </pre>
          </menudescription>
        </menuentry>
        <menuentry>
          <menuleadingtext>
            *
          </menuleadingtext>
          <menunode>
            \vline
          </menunode>
          <menuseparator>
            ::
          </menuseparator>
          <menudescription>
            <pre xml:space="preserve">
              Draw a vertical line.
            </pre>
          </menudescription>
        </menuentry>
        <menuentry>
          <menuleadingtext>
            *
          </menuleadingtext>
          <menunode>
            \cline
          </menunode>
          <menuseparator>
            ::
          </menuseparator>
          <menudescription>
            <pre xml:space="preserve">
              Draw a horizontal line spanning some columns.
            </pre>
          </menudescription>
        </menuentry>
        <menuentry>
          <menuleadingtext>
            *
          </menuleadingtext>
          <menunode>
            \hline
          </menunode>
          <menuseparator>
            ::
          </menuseparator>
          <menudescription>
            <pre xml:space="preserve">
              Draw a horizontal line spanning all columns.
            </pre>
          </menudescription>
        </menuentry>
      </menu>
      <node name="_005cmulticolumn" spaces=" ">
        <nodename>
          \multicolumn
        </nodename>
        <nodenext automatic="on">
          \vline
        </nodenext>
        <nodeup automatic="on">
          tabular
        </nodeup>
      </node>
      <subsection spaces=" ">
        <sectiontitle>
          <code>
            \multicolumn
          </code>
        </sectiontitle>
        <findex index="fn" spaces=" ">
          <indexterm index="fn" number="429" mergedindex="cp">
            \multicolumn
          </indexterm>
        </findex>
        <para>
          Synopsis:
        </para>
        <example endspaces=" ">
          <pre xml:space="preserve">
            \multicolumn
Default handler: &lbrace;
            <var>
              numcols
            </var>
Default handler: &rbrace;
Default handler: &lbrace;
            <var>
              cols
            </var>
Default handler: &rbrace;
Default handler: &lbrace;
            <var>
              text
            </var>
Default handler: &rbrace;
          </pre>
        </example>
        <para>
          Make an
          <code>
            array
          </code>
           or
          <code>
            tabular
          </code>
           entry that spans several columns. The first argument
          <var>
            numcols
          </var>
           gives the number of columns to span. The second argument
          <var>
            cols
          </var>
           specifies the formatting of the entry, with
          <code>
            c
          </code>
           for centered,
          <code>
            l
          </code>
           for flush left, or
          <code>
            r
          </code>
           for flush right. The third argument
          <var>
            text
          </var>
           gives the contents of that entry.
        </para>
        <para>
          In this example, in the first row, the second and third columns are spanned by the single heading
          <samp>
            Name
          </samp>
          .
        </para>
        <example endspaces=" ">
          <pre xml:space="preserve">
            \begin
Default handler: &lbrace;
            tabular
Default handler: &rbrace;
Default handler: &lbrace;
            lccl
Default handler: &rbrace;
             \textit
Default handler: &lbrace;
            ID
Default handler: &rbrace;
            &
            \multicolumn
Default handler: &lbrace;
            2
Default handler: &rbrace;
Default handler: &lbrace;
            c
Default handler: &rbrace;
Default handler: &lbrace;
            \textit
Default handler: &lbrace;
            Name
Default handler: &rbrace;
Default handler: &rbrace;
            &
            \textit
Default handler: &lbrace;
            Age
Default handler: &rbrace;
             \\ \hline 978-0-393-03701-2
            &
            O'Brian
            &
            Patrick
            &
            55 \\ ... \end
Default handler: &lbrace;
            tabular
Default handler: &rbrace;
          </pre>
        </example>
        <para>
          What counts as a column is:
Default handler: &nbsp;
          the column format specifier for the
          <code>
            array
          </code>
           or
          <code>
            tabular
          </code>
           environment is broken into parts, where each part (except the first) begins with
          <code>
            l
          </code>
          ,
          <code>
            c
          </code>
          ,
          <code>
            r
          </code>
          , or
Default handler: &nbsp;
          <code>
            p
          </code>
          . So from
          <code>
            \begin
Default handler: &lbrace;
            tabular
Default handler: &rbrace;
Default handler: &lbrace;
            |r|ccp
Default handler: &lbrace;
            1.5in
Default handler: &rbrace;
            |
Default handler: &rbrace;
          </code>
           the parts are
          <code>
            |r|
          </code>
          ,
          <code>
            c
          </code>
          ,
          <code>
            c
          </code>
          , and
Default handler: &nbsp;
          <code>
            p
Default handler: &lbrace;
            1.5in
Default handler: &rbrace;
            |
          </code>
          .
        </para>
        <para>
          The
          <var>
            cols
          </var>
           argument overrides the
          <code>
            array
          </code>
           or
          <code>
            tabular
          </code>
           environment
Default handler: &textrsquo;
          s intercolumn area default adjoining this multicolumn entry. To affect that area, this argument can contain vertical bars
          <code>
            |
          </code>
           indicating the placement of vertical rules, and
          <codeDefault handler: &arobase;
Default handler: &lbrace;
>
            ...
Default handler: &rbrace;
          </code>
           expressions. Thus if
          <var>
            cols
          </var>
           is
          <samp>
            |c|
          </samp>
           then this multicolumn entry will be centered and a vertical rule will come in the intercolumn area before it and after it. This table details the exact behavior.
        </para>
        <example endspaces=" ">
          <pre xml:space="preserve">
            \begin
Default handler: &lbrace;
            tabular
Default handler: &rbrace;
Default handler: &lbrace;
            |cc|c|c|
Default handler: &rbrace;
             \multicolumn
Default handler: &lbrace;
            1
Default handler: &rbrace;
Default handler: &lbrace;
            r
Default handler: &rbrace;
Default handler: &lbrace;
            w
Default handler: &rbrace;
             % entry one
            &
            \multicolumn
Default handler: &lbrace;
            1
Default handler: &rbrace;
Default handler: &lbrace;
            |r|
Default handler: &rbrace;
Default handler: &lbrace;
            x
Default handler: &rbrace;
             % entry two
            &
            \multicolumn
Default handler: &lbrace;
            1
Default handler: &rbrace;
Default handler: &lbrace;
            |r
Default handler: &rbrace;
Default handler: &lbrace;
            y
Default handler: &rbrace;
             % entry three
            &
            z % entry four \end
Default handler: &lbrace;
            tabular
Default handler: &rbrace;
          </pre>
        </example>
        <noindent/>
        <para>
          Before the first entry the output will not have a vertical rule because the
          <code>
            \multicolumn
          </code>
           has the
          <var>
            cols
          </var>
           specifier
          <samp>
            r
          </samp>
           with no initial vertical bar. Between entry one and entry two there will be a vertical rule; although the first
          <var>
            cols
          </var>
           does not have an ending vertical bar, the second
          <var>
            cols
          </var>
           does have a starting one. Between entry two and entry three there is a single vertical rule; despite that the
          <var>
            cols
          </var>
           in both of the surrounding
          <code>
            multicolumn
          </code>
Default handler: &textrsquo;
          s call for a vertical rule, you only get one rule. Between entry three and entry four there is no vertical rule; the default calls for one but the
          <var>
            cols
          </var>
           in the entry three
          <code>
            \multicolumn
          </code>
           leaves it out, and that takes precedence. Finally, following entry four there is a vertical rule because of the default.
        </para>
        <para>
          The number of spanned columns
          <var>
            numcols
          </var>
           can be 1. Besides giving the ability to change the horizontal alignment, this also is useful to override for one row the
          <code>
            tabular
          </code>
           definition
Default handler: &textrsquo;
          s default intercolumn area specification, including the placement of vertical rules.
        </para>
        <para>
          In the example below, in the
          <code>
            tabular
          </code>
           definition the first column is specified to default to left justified but in the first row the entry is centered with
          <code>
            \multicolumn
Default handler: &lbrace;
            1
Default handler: &rbrace;
Default handler: &lbrace;
            c
Default handler: &rbrace;
Default handler: &lbrace;
            \textsc
Default handler: &lbrace;
            Period
Default handler: &rbrace;
Default handler: &rbrace;
          </code>
          . Also in the first row, the second and third columns are spanned by a single entry with
          <code>
            \multicolumn
Default handler: &lbrace;
            2
Default handler: &rbrace;
Default handler: &lbrace;
            c
Default handler: &rbrace;
Default handler: &lbrace;
            \textsc
Default handler: &lbrace;
            Span
Default handler: &rbrace;
Default handler: &rbrace;
          </code>
          , overriding the specification to center those two columns on the page range en-dash.
        </para>
        <example endspaces=" ">
          <pre xml:space="preserve">
            \begin
Default handler: &lbrace;
            tabular
Default handler: &rbrace;
Default handler: &lbrace;
            l|r
Default handler: &arobase;
Default handler: &lbrace;
            --
Default handler: &rbrace;
            l
Default handler: &rbrace;
             \multicolumn
Default handler: &lbrace;
            1
Default handler: &rbrace;
Default handler: &lbrace;
            c
Default handler: &rbrace;
Default handler: &lbrace;
            \textsc
Default handler: &lbrace;
            Period
Default handler: &rbrace;
Default handler: &rbrace;
            &
            \multicolumn
Default handler: &lbrace;
            2
Default handler: &rbrace;
Default handler: &lbrace;
            c
Default handler: &rbrace;
Default handler: &lbrace;
            \textsc
Default handler: &lbrace;
            Span
Default handler: &rbrace;
Default handler: &rbrace;
             \\ \hline Baroque
            &
            1600
            &
            1760 \\ Classical
            &
            1730
            &
            1820 \\ Romantic
            &
            1780
            &
            1910 \\ Impressionistic
            &
            1875
            &
            1925 \end
Default handler: &lbrace;
            tabular
Default handler: &rbrace;
          </pre>
        </example>
        <noindent/>
        <para>
          Although the
          <code>
            tabular
          </code>
           specification by default puts a vertical rule between the first and second columns, no such vertical rule appears in the first row here. That
Default handler: &textrsquo;
          s because there is no vertical bar in the
          <var>
            cols
          </var>
           part of the first row
Default handler: &textrsquo;
          s first
          <code>
            \multicolumn
          </code>
           command.
        </para>
      </subsection>
      <node name="_005cvline" spaces=" ">
        <nodename>
          \vline
        </nodename>
        <nodenext automatic="on">
          \cline
        </nodenext>
        <nodeprev automatic="on">
          \multicolumn
        </nodeprev>
        <nodeup automatic="on">
          tabular
        </nodeup>
      </node>
      <subsection spaces=" ">
        <sectiontitle>
          <code>
            \vline
          </code>
        </sectiontitle>
        <findex index="fn" spaces=" ">
          <indexterm index="fn" number="430" mergedindex="cp">
            \vline
          </indexterm>
        </findex>
        <para>
          Draw a vertical line in a
          <code>
            tabular
          </code>
           or
          <code>
            array
          </code>
           environment extending the full height and depth of an entry
Default handler: &textrsquo;
          s row. Can also be used in an
Default handler: &arobase;
          -expression, although its synonym vertical bar
Default handler: &nbsp;
          <code>
            |
          </code>
           is more common. This command is rarely used in the body of a table; typically a table
Default handler: &textrsquo;
          s vertical lines are specified in
          <code>
            tabular
          </code>
Default handler: &textrsquo;
          s
          <var>
            cols
          </var>
           argument and overridden as needed with
          <code>
            \multicolumn
          </code>
           (
          <pxref label="tabular">
            <xrefnodename>
              tabular
            </xrefnodename>
          </pxref>
          ).
        </para>
        <para>
          The example below illustrates some pitfalls. In the first row
Default handler: &textrsquo;
          s second entry the
          <code>
            \hfill
          </code>
           moves the
          <code>
            \vline
          </code>
           to the left edge of the cell. But that is different than putting it halfway between the two columns, so between the first and second columns there are two vertical rules, with the one from the
          <codeDefault handler: &lbrace;
>
            c|cc
Default handler: &rbrace;
          </code>
           specifier coming before the one produced by the
          <code>
            \vline\hfill
          </code>
          . In contrast, the first row
Default handler: &textrsquo;
          s third entry shows the usual way to put a vertical bar between two columns. In the second row, the
          <code>
            ghi
          </code>
           is the widest entry in its column so in the
          <code>
            \vline\hfill
          </code>
           the
          <code>
            \hfill
          </code>
           has no effect and the vertical line in that entry appears immediately next to the
          <code>
            g
          </code>
          , with no whitespace.
        </para>
        <example endspaces=" ">
          <pre xml:space="preserve">
            \begin
Default handler: &lbrace;
            tabular
Default handler: &rbrace;
Default handler: &lbrace;
            c|cc
Default handler: &rbrace;
             x
            &
            \vline\hfill y
            &
            \multicolumn
Default handler: &lbrace;
            1
Default handler: &rbrace;
Default handler: &lbrace;
            |r
Default handler: &rbrace;
Default handler: &lbrace;
            z
Default handler: &rbrace;
             \\ % row 1 abc
            &
            def
            &
            \vline\hfill ghi % row 2 \end
Default handler: &lbrace;
            tabular
Default handler: &rbrace;
          </pre>
        </example>
      </subsection>
      <node name="_005ccline" spaces=" ">
        <nodename>
          \cline
        </nodename>
        <nodenext automatic="on">
          \hline
        </nodenext>
        <nodeprev automatic="on">
          \vline
        </nodeprev>
        <nodeup automatic="on">
          tabular
        </nodeup>
      </node>
      <subsection spaces=" ">
        <sectiontitle>
          <code>
            \cline
          </code>
        </sectiontitle>
        <findex index="fn" spaces=" ">
          <indexterm index="fn" number="431" mergedindex="cp">
            \cline
          </indexterm>
        </findex>
        <para>
          Synopsis:
        </para>
        <example endspaces=" ">
          <pre xml:space="preserve">
            \cline
Default handler: &lbrace;
            <var>
              i
            </var>
            -
            <var>
              j
            </var>
Default handler: &rbrace;
          </pre>
        </example>
        <para>
          In an
          <code>
            array
          </code>
           or
          <code>
            tabular
          </code>
           environment, draw a horizontal rule beginning in column
Default handler: &nbsp;
          <var>
            i
          </var>
           and ending in column
Default handler: &nbsp;
          <var>
            j
          </var>
          . The dash,
          <code>
            -
          </code>
          , must appear in the mandatory argument. To span a single column use the number twice, as with
          <code>
            \cline
Default handler: &lbrace;
            2-2
Default handler: &rbrace;
          </code>
          .
        </para>
        <para>
          This example puts two horizontal lines between the first and second rows, one line in the first column only, and the other spanning the third and fourth columns. The two lines are side-by-side, at the same height.
        </para>
        <example endspaces=" ">
          <pre xml:space="preserve">
            \begin
Default handler: &lbrace;
            tabular
Default handler: &rbrace;
Default handler: &lbrace;
            llrr
Default handler: &rbrace;
             a
            &
            b
            &
            c
            &
            d \\ \cline
Default handler: &lbrace;
            1-1
Default handler: &rbrace;
             \cline
Default handler: &lbrace;
            3-4
Default handler: &rbrace;
             e
            &
            f
            &
            g
            &
            h \end
Default handler: &lbrace;
            tabular
Default handler: &rbrace;
          </pre>
        </example>
      </subsection>
      <node name="_005chline" spaces=" ">
        <nodename>
          \hline
        </nodename>
        <nodeprev automatic="on">
          \cline
        </nodeprev>
        <nodeup automatic="on">
          tabular
        </nodeup>
      </node>
      <subsection spaces=" ">
        <sectiontitle>
          <code>
            \hline
          </code>
        </sectiontitle>
        <findex index="fn" spaces=" ">
          <indexterm index="fn" number="432" mergedindex="cp">
            \hline
          </indexterm>
        </findex>
        <para>
          Draw a horizontal line the width of the enclosing
          <code>
            tabular
          </code>
           or
          <code>
            array
          </code>
           environment. It
Default handler: &textrsquo;
          s most commonly used to draw a line at the top, bottom, and between the rows of a table.
        </para>
        <para>
          In this example the top of the table has two horizontal rules, one above the other, that span both columns. The bottom of the table has a single rule spanning both columns. Because of the
          <code>
            \hline
          </code>
          , the
          <code>
            tabular
          </code>
           second row
Default handler: &textrsquo;
          s line ending double backslash
Default handler: &nbsp;
          <code>
            \\
          </code>
           is required.
        </para>
        <example endspaces=" ">
          <pre xml:space="preserve">
            \begin
Default handler: &lbrace;
            tabular
Default handler: &rbrace;
Default handler: &lbrace;
            ll
Default handler: &rbrace;
             \hline\hline Baseball
            &
            Red Sox \\ Basketball
            &
            Celtics \\ \hline \end
Default handler: &lbrace;
            tabular
Default handler: &rbrace;
          </pre>
        </example>
      </subsection>
    </section>
    <node name="thebibliography" spaces=" ">
      <nodename>
        thebibliography
      </nodename>
      <nodenext automatic="on">
        theorem
      </nodenext>
      <nodeprev automatic="on">
        tabular
      </nodeprev>
      <nodeup automatic="on">
        Environments
      </nodeup>
    </node>
    <section spaces=" ">
      <sectiontitle>
        <code>
          thebibliography
        </code>
      </sectiontitle>
      <findex index="fn" spaces=" ">
        <indexterm index="fn" number="433" mergedindex="cp">
          <r>
            environment
          </r>
          ,
          <code>
            thebibliography
          </code>
        </indexterm>
      </findex>
      <findex index="fn" spaces=" ">
        <indexterm index="fn" number="434" mergedindex="cp">
          <code>
            thebibliography
          </code>
          <r>
            environment
          </r>
        </indexterm>
      </findex>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="415">
          bibliography, creating (manually)
        </indexterm>
      </cindex>
      <para>
        Synopsis:
      </para>
      <example endspaces=" ">
        <pre xml:space="preserve">
          \begin
Default handler: &lbrace;
          thebibliography
Default handler: &rbrace;
Default handler: &lbrace;
          <var>
            widest-label
          </var>
Default handler: &rbrace;
           \bibitem[
          <var>
            label
          </var>
          ]
Default handler: &lbrace;
          <var>
            cite_key
Default handler: &rbrace;
          </var>
           ... \end
Default handler: &lbrace;
          thebibliography
Default handler: &rbrace;
        </pre>
      </example>
      <para>
        Produce a bibliography or reference list. There are two ways to produce bibliographic lists. This environment is suitable when you have only a few references and can maintain the list by hand.
        <xref label="Using-BibTeX">
          <xrefnodename>
            Using BibTeX
          </xrefnodename>
        </xref>
        , for a more sophisticated approach.
      </para>
      <para>
        This shows the environment with two entries.
      </para>
      <example endspaces=" ">
        <pre xml:space="preserve">
          This work is based on \cite
Default handler: &lbrace;
          latexdps
Default handler: &rbrace;
          . Together they are \cite
Default handler: &lbrace;
          latexdps, texbook
Default handler: &rbrace;
          . ... \begin
Default handler: &lbrace;
          thebibliography
Default handler: &rbrace;
Default handler: &lbrace;
          9
Default handler: &rbrace;
           \bibitem
Default handler: &lbrace;
          latexdps
Default handler: &rbrace;
           Leslie Lamport. \textit
Default handler: &lbrace;
          \LaTeX
Default handler: &lbrace;
Default handler: &rbrace;
          : a document preparation system
Default handler: &rbrace;
          . Addison-Wesley, Reading, Massachusetts, 1993. \bibitem
Default handler: &lbrace;
          texbook
Default handler: &rbrace;
           Donald Ervin Knuth. \textit
Default handler: &lbrace;
          The \TeX book
Default handler: &rbrace;
          . Addison-Wesley, Reading, Massachusetts, 1983. \end
Default handler: &lbrace;
          thebibliography
Default handler: &rbrace;
        </pre>
      </example>
      <noindent/>
      <para>
        This styles the first reference as
        <samp>
          [1] Leslie ...
        </samp>
        , and so that
        <code>
          ... based on \cite
Default handler: &lbrace;
          latexdps
Default handler: &rbrace;
        </code>
         produces the matching
        <samp>
          ... based on [1]
        </samp>
        . The second
        <code>
          \cite
        </code>
         produces
        <samp>
          [1, 2]
        </samp>
        . You must compile the document twice to resolve these references.
      </para>
      <para>
        The mandatory argument
        <var>
          widest-label
        </var>
         is text that, when typeset, is as wide as the widest item label produced by the
        <code>
          \bibitem
        </code>
         commands. The tradition is to use
        <code>
          9
        </code>
         for bibliographies with less than 10 references,
        <code>
          99
        </code>
         for ones with less than 100, etc.
      </para>
      <findex index="fn" spaces=" ">
        <indexterm index="fn" number="435" mergedindex="cp">
          \bibname
        </indexterm>
      </findex>
      <findex index="fn" spaces=" ">
        <indexterm index="fn" number="436" mergedindex="cp">
          \refname
        </indexterm>
      </findex>
      <para>
        The bibliographic list is headed by a title such as
        <samp>
          Bibliography
        </samp>
        . To change it there are two cases. In the
        <file>
          book
        </file>
         and
        <file>
          report
        </file>
         classes, where the top level sectioning is
        <code>
          \chapter
        </code>
         and the default title is
        <samp>
          Bibliography
        </samp>
        , that title is in the macro
        <code>
          \bibname
        </code>
        . For
        <file>
          article
        </file>
        , where the class
Default handler: &textrsquo;
        s top level sectioning is
        <code>
          \section
        </code>
         and the default is
        <samp>
          References
        </samp>
        , the title is in macro
        <code>
          \refname
        </code>
        . Change it by redefining the command, as with
        <code>
          \renewcommand
Default handler: &lbrace;
          \refname
Default handler: &rbrace;
Default handler: &lbrace;
          Cited references
Default handler: &rbrace;
        </code>
        , after
        <code>
          \begin
Default handler: &lbrace;
          document
Default handler: &rbrace;
        </code>
        .
      </para>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="416">
          <r>
            package
          </r>
          ,
          <code>
            babel
          </code>
        </indexterm>
      </cindex>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="417">
          <code>
            babel
          </code>
          <r>
            package
          </r>
        </indexterm>
      </cindex>
      <para>
        Language support packages such as
        <code>
          babel
        </code>
         will automatically redefine
        <code>
          \refname
        </code>
         or
        <code>
          \bibname
        </code>
         to fit the selected language.
      </para>
      <para>
        <xref label="list">
          <xrefnodename>
            list
          </xrefnodename>
        </xref>
        , for the list layout control parameters.
      </para>
      <menu endspaces=" ">
        <menuentry>
          <menuleadingtext>
            *
          </menuleadingtext>
          <menunode>
            \bibitem
          </menunode>
          <menuseparator>
            ::
          </menuseparator>
          <menudescription>
            <pre xml:space="preserve">
              Specify a bibliography item.
            </pre>
          </menudescription>
        </menuentry>
        <menuentry>
          <menuleadingtext>
            *
          </menuleadingtext>
          <menunode>
            \cite
          </menunode>
          <menuseparator>
            ::
          </menuseparator>
          <menudescription>
            <pre xml:space="preserve">
              Refer to a bibliography item.
            </pre>
          </menudescription>
        </menuentry>
        <menuentry>
          <menuleadingtext>
            *
          </menuleadingtext>
          <menunode>
            \nocite
          </menunode>
          <menuseparator>
            ::
          </menuseparator>
          <menudescription>
            <pre xml:space="preserve">
              Include an item in the bibliography.
            </pre>
          </menudescription>
        </menuentry>
        <menuentry>
          <menuleadingtext>
            *
          </menuleadingtext>
          <menunode>
            Using BibTeX
          </menunode>
          <menuseparator>
            ::
          </menuseparator>
          <menudescription>
            <pre xml:space="preserve">
              Automatic generation of bibliographies.
            </pre>
          </menudescription>
        </menuentry>
      </menu>
      <node name="_005cbibitem" spaces=" ">
        <nodename>
          \bibitem
        </nodename>
        <nodenext automatic="on">
          \cite
        </nodenext>
        <nodeup automatic="on">
          thebibliography
        </nodeup>
      </node>
      <subsection spaces=" ">
        <sectiontitle>
          <code>
            \bibitem
          </code>
        </sectiontitle>
        <findex index="fn" spaces=" ">
          <indexterm index="fn" number="437" mergedindex="cp">
            \bibitem
          </indexterm>
        </findex>
        <para>
          Synopsis:
        </para>
        <example endspaces=" ">
          <pre xml:space="preserve">
            \bibitem
Default handler: &lbrace;
            <var>
              cite_key
            </var>
Default handler: &rbrace;
          </pre>
        </example>
        <noindent/>
        <para>
          or
        </para>
        <example endspaces=" ">
          <pre xml:space="preserve">
            \bibitem[
            <var>
              label
            </var>
            ]
Default handler: &lbrace;
            <var>
              cite_key
            </var>
Default handler: &rbrace;
          </pre>
        </example>
        <para>
          Generate an entry labeled by default by a number generated using the
          <code>
            enumi
          </code>
           counter. The
          <dfn>
            citation key
          </dfn>
          <cindex index="cp" spaces=" ">
            <indexterm index="cp" number="418">
              citation key
            </indexterm>
          </cindex>
          <var>
            cite_key
          </var>
           can be any string of letters, numbers, and punctuation symbols (but not comma).
        </para>
        <para>
          <xref label="thebibliography">
            <xrefnodename>
              thebibliography
            </xrefnodename>
          </xref>
          , for an example.
        </para>
        <para>
          When provided, the optional
          <var>
            label
          </var>
           becomes the entry label and the
          <code>
            enumi
          </code>
           counter is not incremented. With this
        </para>
        <example endspaces=" ">
          <pre xml:space="preserve">
            \begin
Default handler: &lbrace;
            thebibliography
Default handler: &rbrace;
             \bibitem[Lamport 1993]
Default handler: &lbrace;
            latexdps
Default handler: &rbrace;
             Leslie Lamport. \textit
Default handler: &lbrace;
            \LaTeX
Default handler: &lbrace;
Default handler: &rbrace;
            : a document preparation system
Default handler: &rbrace;
            . Addison-Wesley, Reading, Massachusetts, 1993. \bibitem
Default handler: &lbrace;
            texbook
Default handler: &rbrace;
             Donald Ervin Knuth. \textit
Default handler: &lbrace;
            The \TeX book
Default handler: &rbrace;
            . Addison-Wesley, Reading, Massachusetts, 1983. \end
Default handler: &lbrace;
            thebibliography
Default handler: &rbrace;
          </pre>
        </example>
        <noindent/>
        <para>
          the first entry will be styled as
          <samp>
            [Lamport 1993] Leslie ...
          </samp>
           (The amount of horizontal space that
Default handler: &latex;
           leaves for the label depends on the
          <var>
            widest-label
          </var>
           argument of the
          <code>
            thebibliography
          </code>
           environment; see
          <ref label="thebibliography">
            <xrefnodename>
              thebibliography
            </xrefnodename>
          </ref>
          .) Similarly,
          <code>
            ... based on \cite
Default handler: &lbrace;
            latexdps
Default handler: &rbrace;
          </code>
           will produce
          <samp>
            ... based on [Lamport 1994]
          </samp>
          .
        </para>
        <para>
          If you mix
          <code>
            \bibitem
          </code>
           entries having a
          <var>
            label
          </var>
           with those that do not then
Default handler: &latex;
           will number the unlabelled ones sequentially. In the example above the
          <code>
            texbook
          </code>
           entry will appear as
          <samp>
            [1] Donald ...
          </samp>
          , despite that it is the second entry.
        </para>
        <para>
          If you use the same
          <var>
            cite_key
          </var>
           twice then you get
          <samp>
            LaTeX Warning: There were multiply-defined labels
          </samp>
          .
        </para>
        <para>
          Under the hood,
Default handler: &latex;
           remembers the
          <var>
            cite_key
          </var>
           and
          <var>
            label
          </var>
           information because
          <code>
            \bibitem
          </code>
           writes it to the auxiliary file
          <file>
            <var>
              jobname
            </var>
            .aux
          </file>
           (
          <pxref label="Jobname">
            <xrefnodename>
              Jobname
            </xrefnodename>
          </pxref>
          ). For instance, the above example causes the two
          <code>
            \bibcite
Default handler: &lbrace;
            latexdps
Default handler: &rbrace;
Default handler: &lbrace;
            Lamport, 1993
Default handler: &rbrace;
          </code>
           and
          <code>
            \bibcite
Default handler: &lbrace;
            texbook
Default handler: &rbrace;
Default handler: &lbrace;
            1
Default handler: &rbrace;
          </code>
           to appear in that file. The
          <file>
            .aux
          </file>
           file is read by the
          <code>
            \begin
Default handler: &lbrace;
            document
Default handler: &rbrace;
          </code>
           command and then the information is available for
          <code>
            \cite
          </code>
           commands. This explains why you need to run
Default handler: &latex;
           twice to resolve references: once to write it out and once to read it in.
        </para>
        <para>
          Because of this two-pass algorithm, when you add a
          <code>
            \bibitem
          </code>
           or change its
          <var>
            cite_key
          </var>
           you may get
          <samp>
            LaTeX Warning: Label(s) may have changed. Rerun to get cross-references right
          </samp>
          . Fix it by recompiling.
        </para>
      </subsection>
      <node name="_005ccite" spaces=" ">
        <nodename>
          \cite
        </nodename>
        <nodenext automatic="on">
          \nocite
        </nodenext>
        <nodeprev automatic="on">
          \bibitem
        </nodeprev>
        <nodeup automatic="on">
          thebibliography
        </nodeup>
      </node>
      <subsection spaces=" ">
        <sectiontitle>
          <code>
            \cite
          </code>
        </sectiontitle>
        <findex index="fn" spaces=" ">
          <indexterm index="fn" number="438" mergedindex="cp">
            \cite
          </indexterm>
        </findex>
        <para>
          Synopsis:
        </para>
        <example endspaces=" ">
          <pre xml:space="preserve">
            \cite
Default handler: &lbrace;
            <var>
              keys
            </var>
Default handler: &rbrace;
          </pre>
        </example>
        <noindent/>
        <para>
          or
        </para>
        <example endspaces=" ">
          <pre xml:space="preserve">
            \cite[
            <var>
              subcite
            </var>
            ]
Default handler: &lbrace;
            <var>
              keys
            </var>
Default handler: &rbrace;
          </pre>
        </example>
        <para>
          Generate as output a citation to the references associated with
          <var>
            keys
          </var>
          . The mandatory
          <var>
            keys
          </var>
           is a citation key, or a comma-separated list of citation keys (
          <pxref label="_005cbibitem">
            <xrefnodename>
              \bibitem
            </xrefnodename>
          </pxref>
          ).
        </para>
        <para>
          This
        </para>
        <example endspaces=" ">
          <pre xml:space="preserve">
            The ultimate source is \cite
Default handler: &lbrace;
            texbook
Default handler: &rbrace;
            . ... \begin
Default handler: &lbrace;
            thebibliography
Default handler: &rbrace;
             \bibitem
Default handler: &lbrace;
            texbook
Default handler: &rbrace;
             Donald Ervin Knuth. \textit
Default handler: &lbrace;
            The \TeX book
Default handler: &rbrace;
            . Addison-Wesley, Reading, Massachusetts, 1983. \end
Default handler: &lbrace;
            thebibliography
Default handler: &rbrace;
          </pre>
        </example>
        <noindent/>
        <para>
          produces output like
          <samp>
            ... source is [1]
          </samp>
          . You can change the appearance of the citation and of the reference by using bibliography styles if you generate automatically the
          <code>
            thebibliography
          </code>
           environment. More information in
          <ref label="Using-BibTeX">
            <xrefnodename>
              Using BibTeX
            </xrefnodename>
          </ref>
          .
        </para>
        <para>
          The optional argument
          <var>
            subcite
          </var>
           is appended to the citation. For example,
          <code>
            See 14.3 in \cite[p.~314]
Default handler: &lbrace;
            texbook
Default handler: &rbrace;
          </code>
           might produce
          <samp>
            See 14.3 in [1, p.
Default handler: &nbsp;
            314]
          </samp>
          .
        </para>
        <para>
          In addition to what appears in the output,
          <code>
            \cite
          </code>
           writes information to the auxiliary file
          <file>
            <var>
              jobname
            </var>
            .aux
          </file>
           (
          <pxref label="Jobname">
            <xrefnodename>
              Jobname
            </xrefnodename>
          </pxref>
          ). For instance,
          <code>
            \cite
Default handler: &lbrace;
            latexdps
Default handler: &rbrace;
          </code>
           writes
          <samp>
            \citation
Default handler: &lbrace;
            latexdps
Default handler: &rbrace;
          </samp>
           to that file. This information is used by Bib
Default handler: &tex;
           to include in your reference list only those works that you have actually cited; see
          <ref label="_005cnocite">
            <xrefnodename>
              \nocite
            </xrefnodename>
          </ref>
           also.
        </para>
        <para>
          If
          <var>
            keys
          </var>
           is not in your bibliography information then you get
          <samp>
            LaTeX Warning: There were undefined references
          </samp>
          , and in the output the citation shows as a boldface question mark between square brackets. There are two possible causes. If you have mistyped something, as in
          <code>
            \cite
Default handler: &lbrace;
            texbok
Default handler: &rbrace;
          </code>
           then you need to correct the spelling. On the other hand, if you have just added or modified the bibliographic information and so changed the
          <file>
            .aux
          </file>
           file (
          <pxref label="_005cbibitem">
            <xrefnodename>
              \bibitem
            </xrefnodename>
          </pxref>
          ) then the fix may be to run
Default handler: &latex;
           again.
        </para>
      </subsection>
      <node name="_005cnocite" spaces=" ">
        <nodename>
          \nocite
        </nodename>
        <nodenext automatic="on">
          Using BibTeX
        </nodenext>
        <nodeprev automatic="on">
          \cite
        </nodeprev>
        <nodeup automatic="on">
          thebibliography
        </nodeup>
      </node>
      <subsection spaces=" ">
        <sectiontitle>
          <code>
            \nocite
          </code>
        </sectiontitle>
        <findex index="fn" spaces=" ">
          <indexterm index="fn" number="439" mergedindex="cp">
            \nocite
          </indexterm>
        </findex>
        <para>
          Synopsis:
        </para>
        <example endspaces=" ">
          <pre xml:space="preserve">
            <code>
              \nocite
Default handler: &lbrace;
              <var>
                keys
              </var>
Default handler: &rbrace;
            </code>
          </pre>
        </example>
        <para>
          Produces no output but writes
          <var>
            keys
          </var>
           to the auxiliary file
          <file>
            <var>
              jobname
            </var>
            .aux
          </file>
           (
          <pxref label="Jobname">
            <xrefnodename>
              Jobname
            </xrefnodename>
          </pxref>
          ).
        </para>
        <para>
          The mandatory argument
          <var>
            keys
          </var>
           is a comma-separated list of one or more citation keys (
          <pxref label="_005cbibitem">
            <xrefnodename>
              \bibitem
            </xrefnodename>
          </pxref>
          ). This information is used by Bib
Default handler: &tex;
           to include these works in your reference list even though you have not explicitly cited them (
          <pxref label="_005ccite">
            <xrefnodename>
              \cite
            </xrefnodename>
          </pxref>
          ).
        </para>
      </subsection>
      <node name="Using-BibTeX" spaces=" ">
        <nodename>
          Using BibTeX
        </nodename>
        <nodeprev automatic="on">
          \nocite
        </nodeprev>
        <nodeup automatic="on">
          thebibliography
        </nodeup>
      </node>
      <subsection spaces=" ">
        <sectiontitle>
          Using Bib
Default handler: &tex;
        </sectiontitle>
        <cindex index="cp" spaces=" ">
          <indexterm index="cp" number="419">
            using Bib
Default handler: &tex;
          </indexterm>
        </cindex>
        <cindex index="cp" spaces=" ">
          <indexterm index="cp" number="420">
            bib
Default handler: &tex;
            , using
          </indexterm>
        </cindex>
        <cindex index="cp" spaces=" ">
          <indexterm index="cp" number="421">
            bibliography, creating (automatically)
          </indexterm>
        </cindex>
        <findex index="fn" spaces=" ">
          <indexterm index="fn" number="440" mergedindex="cp">
            \bibliographystyle
          </indexterm>
        </findex>
        <findex index="fn" spaces=" ">
          <indexterm index="fn" number="441" mergedindex="cp">
            \bibliography
          </indexterm>
        </findex>
        <para>
          As described in
          <code>
            thebibliography
          </code>
           (
          <pxref label="thebibliography">
            <xrefnodename>
              thebibliography
            </xrefnodename>
          </pxref>
          ), a sophisticated approach to managing bibliographies is provided by the Bib
Default handler: &tex;
           program. This is only an introduction; see the full documentation on CTAN (
          <pxref label="CTAN">
            <xrefnodename>
              CTAN
            </xrefnodename>
          </pxref>
          ).
        </para>
        <para>
          With Bib
Default handler: &tex;
          , you don
Default handler: &textrsquo;
          t use the
          <code>
            thebibliography
          </code>
           environment directly (
          <pxref label="thebibliography">
            <xrefnodename>
              thebibliography
            </xrefnodename>
          </pxref>
          ). Instead, include these lines:
        </para>
        <example endspaces=" ">
          <pre xml:space="preserve">
            \bibliographystyle
Default handler: &lbrace;
            <var>
              bibstyle
            </var>
Default handler: &rbrace;
             \bibliography
Default handler: &lbrace;
            <var>
              bibfile1
            </var>
            ,
            <var>
              bibfile2
            </var>
            , ...
Default handler: &rbrace;
          </pre>
        </example>
        <noindent/>
        <para>
          The
          <var>
            bibstyle
          </var>
           refers to a file
          <file>
            <var>
              bibstyle
            </var>
            .bst
          </file>
          , which defines how your citations will look. The standard
          <var>
            bibstyle
          </var>
Default handler: &textrsquo;
          s distributed with Bib
Default handler: &tex;
           are:
        </para>
        <table commandarg="code" spaces=" " endspaces=" ">
          <tableentry>
            <tableterm>
              <item spaces=" ">
                <itemformat command="code">
                  alpha
                </itemformat>
              </item>
            </tableterm>
            <tableitem>
              <para>
                Labels are formed from name of author and year of publication. The bibliographic items are sorted alphabetically.
              </para>
            </tableitem>
          </tableentry>
          <tableentry>
            <tableterm>
              <item spaces=" ">
                <itemformat command="code">
                  plain
                </itemformat>
              </item>
            </tableterm>
            <tableitem>
              <para>
                Labels are integers. Sort the bibliographic items alphabetically.
              </para>
            </tableitem>
          </tableentry>
          <tableentry>
            <tableterm>
              <item spaces=" ">
                <itemformat command="code">
                  unsrt
                </itemformat>
              </item>
            </tableterm>
            <tableitem>
              <para>
                Like
                <code>
                  plain
                </code>
                , but entries are in order of citation.
              </para>
            </tableitem>
          </tableentry>
          <tableentry>
            <tableterm>
              <item spaces=" ">
                <itemformat command="code">
                  abbrv
                </itemformat>
              </item>
            </tableterm>
            <tableitem>
              <para>
                Like
                <code>
                  plain
                </code>
                , but more compact labels.
              </para>
            </tableitem>
          </tableentry>
        </table>
        <noindent/>
        <para>
          Many, many other Bib
Default handler: &tex;
           style files exist, tailored to the demands of various publications. See the CTAN topic
          <url>
            <urefurl>
              https://ctan.org/topic/bibtex-sty
            </urefurl>
          </url>
          .
        </para>
        <para>
          The
          <code>
            \bibliography
          </code>
           command is what actually produces the bibliography. Its argument is a comma-separated list, referring to files named
          <file>
            <var>
              bibfile1
            </var>
            .bib
          </file>
          ,
          <file>
            <var>
              bibfile2
            </var>
            .bib
          </file>
          ,
Default handler: &dots;
           These contain your database in Bib
Default handler: &tex;
           format. This shows a typical couple of entries in that format.
        </para>
        <example endspaces=" ">
          <pre xml:space="preserve"Default handler: &arobase;
>
            book
Default handler: &lbrace;
            texbook, title =
Default handler: &lbrace;
            The
Default handler: &lbrace;
Default handler: &lbrace;
            \TeX
Default handler: &rbrace;
Default handler: &rbrace;
            book
Default handler: &rbrace;
            , author =
Default handler: &lbrace;
            D.E. Knuth
Default handler: &rbrace;
            , isbn =
Default handler: &lbrace;
            0201134489
Default handler: &rbrace;
            , series =
Default handler: &lbrace;
            Computers \
            &
             typesetting
Default handler: &rbrace;
            , year =
Default handler: &lbrace;
            1983
Default handler: &rbrace;
            , publisher =
Default handler: &lbrace;
            Addison-Wesley
Default handler: &rbrace;
Default handler: &rbrace;
Default handler: &arobase;
            book
Default handler: &lbrace;
            sexbook, author =
Default handler: &lbrace;
            W.H. Masters and V.E. Johnson
Default handler: &rbrace;
            , title =
Default handler: &lbrace;
            Human Sexual Response
Default handler: &rbrace;
            , year =
Default handler: &lbrace;
            1966
Default handler: &rbrace;
            , publisher =
Default handler: &lbrace;
            Bantam Books
Default handler: &rbrace;
Default handler: &rbrace;
          </pre>
        </example>
        <para>
          Only the bibliographic entries referred to via
          <code>
            \cite
          </code>
           and
          <code>
            \nocite
          </code>
           will be listed in the document
Default handler: &textrsquo;
          s bibliography. Thus you can keep all your sources together in one file, or a small number of files, and rely on Bib
Default handler: &tex;
           to include in this document only those that you used.
        </para>
        <cindex index="cp" spaces=" ">
          <indexterm index="cp" number="422">
            <samp>
              *
            </samp>
            , to
            <code>
              \nocite
            </code>
             all keys
          </indexterm>
        </cindex>
        <findex index="fn" spaces=" ">
          <indexterm index="fn" number="442" mergedindex="cp">
            \nocite
            <rDefault handler: &lbrace;
>
              *
Default handler: &rbrace;
              , for all keys
            </r>
          </indexterm>
        </findex>
        <para>
          With Bib
Default handler: &tex;
          , the
          <var>
            keys
          </var>
           argument to
          <code>
            \nocite
          </code>
           can also be the single character
          <samp>
            *
          </samp>
          . This means to implicitly cite all entries from all given bibliographies.
        </para>
        <menu endspaces=" ">
          <menuentry>
            <menuleadingtext>
              *
            </menuleadingtext>
            <menunode>
              Bib
Default handler: &tex;
               error messages
            </menunode>
            <menuseparator>
              ::
            </menuseparator>
            <menudescription>
              <pre xml:space="preserve"/>
            </menudescription>
          </menuentry>
        </menu>
        <node name="BibTeX-error-messages" spaces=" ">
          <nodename>
            Bib
Default handler: &tex;
             error messages
          </nodename>
          <nodeup automatic="on">
            Using BibTeX
          </nodeup>
        </node>
        <subsubsection spaces=" ">
          <sectiontitle>
            Bib
Default handler: &tex;
             error messages
          </sectiontitle>
          <cindex index="cp" spaces=" ">
            <indexterm index="cp" number="423">
              Bib
Default handler: &tex;
               error messages
            </indexterm>
          </cindex>
          <cindex index="cp" spaces=" ">
            <indexterm index="cp" number="424">
              error messages, from Bib
Default handler: &tex;
            </indexterm>
          </cindex>
          <findex index="fn" spaces=" ">
            <indexterm index="fn" number="443" mergedindex="cp">
              .aux
              <r>
                file and Bib
Default handler: &tex;
                 commands
              </r>
            </indexterm>
          </findex>
          <para>
            If you forget to use
            <code>
              \bibliography
            </code>
             or
            <code>
              \bibliographystyle
            </code>
             in your document (or, less likely, any
            <code>
              \cite
            </code>
             or
            <code>
              \nocite
            </code>
             command), Bib
Default handler: &tex;
             will issue an error message. Because Bib
Default handler: &tex;
             can be used with any program, not just
Default handler: &latex;
            , the error messages refer to the internal commands read by Bib
Default handler: &tex;
             (from the
            <file>
              .aux
            </file>
             file), rather than the user-level commands described above.
          </para>
          <para>
            Here is a table showing internal commands mentioned in the Bib
Default handler: &tex;
             errors, and the corresponding user-level commands.
          </para>
          <ftable commandarg="code" spaces=" " endspaces=" ">
            <tableentry>
              <tableterm>
                <item spaces=" ">
                  <itemformat command="code">
                    <indexterm index="fn" number="444" mergedindex="cp">
                      \bibdata
                    </indexterm>
                    \bibdata
                  </itemformat>
                </item>
              </tableterm>
              <tableitem>
                <findex index="fn" spaces=" ">
                  <indexterm index="fn" number="445" mergedindex="cp">
                    \bibliography
                    <r>
                      and internal
                      <code>
                        \bibdata
                      </code>
                    </r>
                  </indexterm>
                </findex>
                <para>
                  <code>
                    \bibliography
                  </code>
                </para>
              </tableitem>
            </tableentry>
            <tableentry>
              <tableterm>
                <item spaces=" ">
                  <itemformat command="code">
                    <indexterm index="fn" number="446" mergedindex="cp">
                      \bibstyle
                    </indexterm>
                    \bibstyle
                  </itemformat>
                </item>
              </tableterm>
              <tableitem>
                <findex index="fn" spaces=" ">
                  <indexterm index="fn" number="447" mergedindex="cp">
                    \bibliographystyle
                    <r>
                      and internal
                      <code>
                        \bibstyle
                      </code>
                    </r>
                  </indexterm>
                </findex>
                <para>
                  <code>
                    \bibliographystyle
                  </code>
                </para>
              </tableitem>
            </tableentry>
            <tableentry>
              <tableterm>
                <item spaces=" ">
                  <itemformat command="code">
                    <indexterm index="fn" number="448" mergedindex="cp">
                      \citation
                    </indexterm>
                    \citation
                  </itemformat>
                </item>
              </tableterm>
              <tableitem>
                <findex index="fn" spaces=" ">
                  <indexterm index="fn" number="449" mergedindex="cp">
                    \cite
                    <r>
                      and internal
                      <code>
                        \citation
                      </code>
                    </r>
                  </indexterm>
                </findex>
                <findex index="fn" spaces=" ">
                  <indexterm index="fn" number="450" mergedindex="cp">
                    \nocite
                    <r>
                      and internal
                      <code>
                        \citation
                      </code>
                    </r>
                  </indexterm>
                </findex>
                <para>
                  <code>
                    \cite
                  </code>
                  ,
                  <code>
                    \nocite
                  </code>
                </para>
              </tableitem>
            </tableentry>
          </ftable>
          <para>
            For example, if your document has no
            <code>
              \bibliographystyle
            </code>
             command, Bib
Default handler: &tex;
             complains as follows:
          </para>
          <example endspaces=" ">
            <pre xml:space="preserve">
              I found no \bibstyle command---while reading file
              <var>
                document
              </var>
              .aux
            </pre>
          </example>
        </subsubsection>
      </subsection>
    </section>
    <node name="theorem" spaces=" ">
      <nodename>
        theorem
      </nodename>
      <nodenext automatic="on">
        titlepage
      </nodenext>
      <nodeprev automatic="on">
        thebibliography
      </nodeprev>
      <nodeup automatic="on">
        Environments
      </nodeup>
    </node>
    <section spaces=" ">
      <sectiontitle>
        <code>
          theorem
        </code>
      </sectiontitle>
      <findex index="fn" spaces=" ">
        <indexterm index="fn" number="451" mergedindex="cp">
          <r>
            environment
          </r>
          ,
          <code>
            theorem
          </code>
        </indexterm>
      </findex>
      <findex index="fn" spaces=" ">
        <indexterm index="fn" number="452" mergedindex="cp">
          <code>
            theorem
          </code>
          <r>
            environment
          </r>
        </indexterm>
      </findex>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="425">
          theorems, typesetting
        </indexterm>
      </cindex>
      <para>
        Synopsis:
      </para>
      <example endspaces=" ">
        <pre xml:space="preserve">
          \begin
Default handler: &lbrace;
          theorem
Default handler: &rbrace;
          <var>
            theorem body
          </var>
           \end
Default handler: &lbrace;
          theorem
Default handler: &rbrace;
        </pre>
      </example>
      <para>
        Produces
        <samp>
          Theorem
          <var>
            n
          </var>
        </samp>
         in boldface followed by
        <var>
          theorem body
        </var>
         in italics. The numbering possibilities for
        <var>
          n
        </var>
         are described under
        <code>
          \newtheorem
        </code>
         (
        <pxref label="_005cnewtheorem">
          <xrefnodename>
            \newtheorem
          </xrefnodename>
        </pxref>
        ).
      </para>
      <example endspaces=" ">
        <pre xml:space="preserve">
          \newtheorem
Default handler: &lbrace;
          lem
Default handler: &rbrace;
Default handler: &lbrace;
          Lemma
Default handler: &rbrace;
           % in preamble \newtheorem
Default handler: &lbrace;
          thm
Default handler: &rbrace;
Default handler: &lbrace;
          Theorem
Default handler: &rbrace;
           ... \begin
Default handler: &lbrace;
          lem
Default handler: &rbrace;
           % in document body text of lemma \end
Default handler: &lbrace;
          lem
Default handler: &rbrace;
           The next result follows immediately. \begin
Default handler: &lbrace;
          thm
Default handler: &rbrace;
          [Gauss] % put `Gauss' in parens after theorem head text of theorem \end
Default handler: &lbrace;
          thm
Default handler: &rbrace;
        </pre>
      </example>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="426">
          <r>
            package
          </r>
          ,
          <code>
            amsmath
          </code>
        </indexterm>
      </cindex>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="427">
          <code>
            amsmath
          </code>
          <r>
            package
          </r>
        </indexterm>
      </cindex>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="428">
          <r>
            package
          </r>
          ,
          <code>
            amsthm
          </code>
        </indexterm>
      </cindex>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="429">
          <code>
            amsthm
          </code>
          <r>
            package
          </r>
        </indexterm>
      </cindex>
      <para>
        Most new documents use the packages
        <code>
          amsthm
        </code>
         and
        <code>
          amsmath
        </code>
         from the American Mathematical Society. Among other things these packages include a large number of options for theorem environments, such as styling options.
      </para>
    </section>
    <node name="titlepage" spaces=" ">
      <nodename>
        titlepage
      </nodename>
      <nodenext automatic="on">
        verbatim
      </nodenext>
      <nodeprev automatic="on">
        theorem
      </nodeprev>
      <nodeup automatic="on">
        Environments
      </nodeup>
    </node>
    <section spaces=" ">
      <sectiontitle>
        <code>
          titlepage
        </code>
      </sectiontitle>
      <findex index="fn" spaces=" ">
        <indexterm index="fn" number="453" mergedindex="cp">
          <r>
            environment
          </r>
          ,
          <code>
            titlepage
          </code>
        </indexterm>
      </findex>
      <findex index="fn" spaces=" ">
        <indexterm index="fn" number="454" mergedindex="cp">
          <code>
            titlepage
          </code>
          <r>
            environment
          </r>
        </indexterm>
      </findex>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="430">
          making a title page
        </indexterm>
      </cindex>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="431">
          title pages, creating
        </indexterm>
      </cindex>
      <para>
        Synopsis:
      </para>
      <example endspaces=" ">
        <pre xml:space="preserve">
          \begin
Default handler: &lbrace;
          titlepage
Default handler: &rbrace;
           ... text and spacing ... \end
Default handler: &lbrace;
          titlepage
Default handler: &rbrace;
        </pre>
      </example>
      <para>
        Create a title page, a page with no printed page number or heading and with succeeding pages numbered starting with page one.
      </para>
      <para>
        In this example all formatting, including vertical spacing, is left to the author.
      </para>
      <example endspaces=" ">
        <pre xml:space="preserve">
          \begin
Default handler: &lbrace;
          titlepage
Default handler: &rbrace;
           \vspace*
Default handler: &lbrace;
          \stretch
Default handler: &lbrace;
          1
Default handler: &rbrace;
Default handler: &rbrace;
           \begin
Default handler: &lbrace;
          center
Default handler: &rbrace;
Default handler: &lbrace;
          \huge\bfseries Thesis \\[1ex] title
Default handler: &rbrace;
           \\[6.5ex]
Default handler: &lbrace;
          \large\bfseries Author name
Default handler: &rbrace;
           \\ \vspace
Default handler: &lbrace;
          4ex
Default handler: &rbrace;
           Thesis submitted to \\[5pt] \textit
Default handler: &lbrace;
          University name
Default handler: &rbrace;
           \\[2cm] in partial fulfilment for the award of the degree of \\[2cm] \textsc
Default handler: &lbrace;
          \Large Doctor of Philosophy
Default handler: &rbrace;
           \\[2ex] \textsc
Default handler: &lbrace;
          \large Mathematics
Default handler: &rbrace;
           \\[12ex] \vfill Department of Mathematics \\ Address \\ \vfill \today \end
Default handler: &lbrace;
          center
Default handler: &rbrace;
           \vspace
Default handler: &lbrace;
          \stretch
Default handler: &lbrace;
          2
Default handler: &rbrace;
Default handler: &rbrace;
           \end
Default handler: &lbrace;
          titlepage
Default handler: &rbrace;
        </pre>
      </example>
      <para>
        To instead produce a standard title page without a
        <code>
          titlepage
        </code>
         environment, use
        <code>
          \maketitle
        </code>
         (
        <pxref label="_005cmaketitle">
          <xrefnodename>
            \maketitle
          </xrefnodename>
        </pxref>
        ).
      </para>
    </section>
    <node name="verbatim" spaces=" ">
      <nodename>
        verbatim
      </nodename>
      <nodenext automatic="on">
        verse
      </nodenext>
      <nodeprev automatic="on">
        titlepage
      </nodeprev>
      <nodeup automatic="on">
        Environments
      </nodeup>
    </node>
    <section spaces=" ">
      <sectiontitle>
        <code>
          verbatim
        </code>
      </sectiontitle>
      <findex index="fn" spaces=" ">
        <indexterm index="fn" number="455" mergedindex="cp">
          <r>
            environment
          </r>
          ,
          <code>
            verbatim
          </code>
        </indexterm>
      </findex>
      <findex index="fn" spaces=" ">
        <indexterm index="fn" number="456" mergedindex="cp">
          <code>
            verbatim
          </code>
          <r>
            environment
          </r>
        </indexterm>
      </findex>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="432">
          verbatim text
        </indexterm>
      </cindex>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="433">
          simulating typed text
        </indexterm>
      </cindex>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="434">
          typed text, simulating
        </indexterm>
      </cindex>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="435">
          code, typesetting
        </indexterm>
      </cindex>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="436">
          computer programs, typesetting
        </indexterm>
      </cindex>
      <para>
        Synopsis:
      </para>
      <example endspaces=" ">
        <pre xml:space="preserve">
          \begin
Default handler: &lbrace;
          verbatim
Default handler: &rbrace;
          <var>
            literal-text
          </var>
           \end
Default handler: &lbrace;
          verbatim
Default handler: &rbrace;
        </pre>
      </example>
      <para>
        A paragraph-making environment in which
Default handler: &latex;
         produces as output exactly what you type as input. For instance inside
        <var>
          literal-text
        </var>
         the backslash
Default handler: &nbsp;
        <code>
          \
        </code>
         character does not start commands, it produces a printed
        <samp>
          \
        </samp>
        , and carriage returns and blanks are taken literally. The output appears in a monospaced typewriter-like font (
        <code>
          \tt
        </code>
        ).
      </para>
      <example endspaces=" ">
        <pre xml:space="preserve">
          \begin
Default handler: &lbrace;
          verbatim
Default handler: &rbrace;
           Symbol swearing: %
          &
          $#?
Default handler: &eosexcl;
          . \end
Default handler: &lbrace;
          verbatim
Default handler: &rbrace;
        </pre>
      </example>
      <para>
        The only restriction on
        <code>
          literal-text
        </code>
         is that it cannot include the string
        <code>
          \end
Default handler: &lbrace;
          verbatim
Default handler: &rbrace;
        </code>
        .
      </para>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="437">
          <r>
            package
          </r>
          ,
          <code>
            cprotect
          </code>
        </indexterm>
      </cindex>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="438">
          <code>
            cprotect
          </code>
          <r>
            package
          </r>
        </indexterm>
      </cindex>
      <para>
        You cannot use the verbatim environment in the argument to macros, for instance in the argument to a
        <code>
          \section
        </code>
        . This is not the same as commands being fragile (
        <pxref label="_005cprotect">
          <xrefnodename>
            \protect
          </xrefnodename>
        </pxref>
        ), instead it just cannot work, as the
        <code>
          verbatim
        </code>
         environment changes the catcode regime before processing its contents, and restore it immediately afterward, nevertheless with a macro argument the content of the argument has already be converted to a token list along the catcode regime in effect when the macro was called. However, the
        <code>
          cprotect
        </code>
         package can help with this.
      </para>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="439">
          <r>
            package
          </r>
          ,
          <code>
            listings
          </code>
        </indexterm>
      </cindex>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="440">
          <code>
            listings
          </code>
          <r>
            package
          </r>
        </indexterm>
      </cindex>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="441">
          <r>
            package
          </r>
          ,
          <code>
            minted
          </code>
        </indexterm>
      </cindex>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="442">
          <code>
            minted
          </code>
          <r>
            package
          </r>
        </indexterm>
      </cindex>
      <para>
        One common use of verbatim input is to typeset computer code. Some packages offer many features not provided by the
        <code>
          verbatim
        </code>
         environment; two of the most popular are
        <code>
          listings
        </code>
         and
        <code>
          minted
        </code>
        . For example, they are capable of pretty-printing, line numbering, and selecting parts of files for a continuing listing.
      </para>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="443">
          <r>
            package
          </r>
          ,
          <code>
            fancyvrb
          </code>
        </indexterm>
      </cindex>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="444">
          <code>
            fancyvrb
          </code>
          <r>
            package
          </r>
        </indexterm>
      </cindex>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="445">
          <r>
            package
          </r>
          ,
          <code>
            verbatimbox
          </code>
        </indexterm>
      </cindex>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="446">
          <code>
            verbatimbox
          </code>
          <r>
            package
          </r>
        </indexterm>
      </cindex>
      <para>
        A package that provides many more options for verbatim environments is
        <code>
          fancyvrb
        </code>
        . Another is
        <code>
          verbatimbox
        </code>
        .
      </para>
      <para>
        For a list of all the relevant packages, see CTAN (
        <pxref label="CTAN">
          <xrefnodename>
            CTAN
          </xrefnodename>
        </pxref>
        ), particularly the topics
        <code>
          listing
        </code>
         (
        <url>
          <urefurl>
            https://ctan.org/topic/listing
          </urefurl>
        </url>
        ) and
        <code>
          verbatim
        </code>
         (
        <url>
          <urefurl>
            https://ctan.org/topic/verbatim
          </urefurl>
        </url>
        ).
      </para>
      <menu endspaces=" ">
        <menuentry>
          <menuleadingtext>
            *
          </menuleadingtext>
          <menunode>
            \verb
          </menunode>
          <menuseparator>
            ::
          </menuseparator>
          <menudescription>
            <pre xml:space="preserve">
              The macro form of the
              <code>
                verbatim
              </code>
               environment.
            </pre>
          </menudescription>
        </menuentry>
      </menu>
      <node name="_005cverb" spaces=" ">
        <nodename>
          \verb
        </nodename>
        <nodeup automatic="on">
          verbatim
        </nodeup>
      </node>
      <subsection spaces=" ">
        <sectiontitle>
          <code>
            \verb
          </code>
        </sectiontitle>
        <findex index="fn" spaces=" ">
          <indexterm index="fn" number="457" mergedindex="cp">
            \verb
          </indexterm>
        </findex>
        <cindex index="cp" spaces=" ">
          <indexterm index="cp" number="447">
            verbatim text, inline
          </indexterm>
        </cindex>
        <para>
          Synopsis:
        </para>
        <example endspaces=" ">
          <pre xml:space="preserve">
            \verb
            <var>
              char
            </var>
            <var>
              literal-text
            </var>
            <var>
              char
            </var>
             \verb*
            <var>
              char
            </var>
            <var>
              literal-text
            </var>
            <var>
              char
            </var>
          </pre>
        </example>
        <para>
          Typeset
          <var>
            literal-text
          </var>
           as it is input, including special characters and spaces, using the typewriter (
          <code>
            \tt
          </code>
          ) font.
        </para>
        <para>
          This example shows two different invocations of
          <code>
            \verb
          </code>
          .
        </para>
        <example endspaces=" ">
          <pre xml:space="preserve">
            This is \verb!literally! the biggest pumpkin ever. And this is the best squash, \verb+literally!+
          </pre>
        </example>
        <noindent/>
        <para>
          The first
          <code>
            \verb
          </code>
           has its
          <var>
            literal-text
          </var>
           surrounded with exclamation point,
          <code>
            !
          </code>
          . The second instead uses plus,
          <code>
            +
          </code>
          , because the exclamation point is part of
          <code>
            literal-text
          </code>
          .
        </para>
        <para>
          The single-character delimiter
          <var>
            char
          </var>
           surrounds
          <var>
            literal-text
          </var>
Default handler: &textmdash;
          it must be the same character before and after. No spaces come between
          <code>
            \verb
          </code>
           or
          <code>
            \verb*
          </code>
           and
          <var>
            char
          </var>
          , or between
          <var>
            char
          </var>
           and
          <var>
            literal-text
          </var>
          , or between
          <var>
            literal-text
          </var>
           and the second occurrence of
          <var>
            char
          </var>
           (the synopsis shows a space only to distinguish one component from the other). The delimiter must not appear in
          <var>
            literal-text
          </var>
          . The
          <var>
            literal-text
          </var>
           cannot include a line break.
        </para>
        <cindex index="cp" spaces=" ">
          <indexterm index="cp" number="448">
            visible space
          </indexterm>
        </cindex>
        <para>
          The
          <code>
            *
          </code>
          -form differs only in that spaces are printed with a visible space character.
          <tex endspaces=" ">
             (Namely, {\tt\char`\ }.)
          </tex>
        </para>
        <para>
          The output from this will include a visible space on both side of word
          <samp>
            with
          </samp>
          :
        </para>
        <example endspaces=" ">
          <pre xml:space="preserve">
            The command's first argument is \verb*!filename with extension! and ...
          </pre>
        </example>
        <cindex index="cp" spaces=" ">
          <indexterm index="cp" number="449">
            <r>
              package
            </r>
            ,
            <code>
              url
            </code>
          </indexterm>
        </cindex>
        <cindex index="cp" spaces=" ">
          <indexterm index="cp" number="450">
            <code>
              url
            </code>
            <r>
              package
            </r>
          </indexterm>
        </cindex>
        <para>
          For typesetting Internet addresses, urls, the package
          <code>
            url
          </code>
           is a better option than the
          <code>
            \verb
          </code>
           command, since it allows line breaks.
        </para>
        <cindex index="cp" spaces=" ">
          <indexterm index="cp" number="451">
            <r>
              package
            </r>
            ,
            <code>
              cprotect
            </code>
          </indexterm>
        </cindex>
        <cindex index="cp" spaces=" ">
          <indexterm index="cp" number="452">
            <code>
              cprotect
            </code>
            <r>
              package
            </r>
          </indexterm>
        </cindex>
        <para>
          You cannot use
          <code>
            \verb
          </code>
           in the argument to a macro, for instance in the argument to a
          <code>
            \section
          </code>
          . It is not a question of
          <code>
            \verb
          </code>
           being fragile (
          <pxref label="_005cprotect">
            <xrefnodename>
              \protect
            </xrefnodename>
          </pxref>
          ), instead it just cannot work, as the
          <code>
            \verb
          </code>
           command changes the catcode regime before reading its argument, and restore it immediately afterward, nevertheless with a macro argument the content of the argument has already be converted to a token list along the catcode regime in effect when the macro was called. However, the
          <code>
            cprotect
          </code>
           package can help with this.
        </para>
      </subsection>
    </section>
    <node name="verse" spaces=" ">
      <nodename>
        verse
      </nodename>
      <nodeprev automatic="on">
        verbatim
      </nodeprev>
      <nodeup automatic="on">
        Environments
      </nodeup>
    </node>
    <section spaces=" ">
      <sectiontitle>
        <code>
          verse
        </code>
      </sectiontitle>
      <findex index="fn" spaces=" ">
        <indexterm index="fn" number="458" mergedindex="cp">
          <r>
            environment
          </r>
          ,
          <code>
            verse
          </code>
        </indexterm>
      </findex>
      <findex index="fn" spaces=" ">
        <indexterm index="fn" number="459" mergedindex="cp">
          <code>
            verse
          </code>
          <r>
            environment
          </r>
        </indexterm>
      </findex>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="453">
          poetry, an environment for
        </indexterm>
      </cindex>
      <para>
        Synopsis:
      </para>
      <example endspaces=" ">
        <pre xml:space="preserve">
          \begin
Default handler: &lbrace;
          verse
Default handler: &rbrace;
          <var>
            line1
          </var>
           \\
          <var>
            line2
          </var>
           \\ ... \end
Default handler: &lbrace;
          verse
Default handler: &rbrace;
        </pre>
      </example>
      <para>
        An environment for poetry.
      </para>
      <para>
        Here are two lines from Shakespeare
Default handler: &textrsquo;
        s Romeo and Juliet.
      </para>
      <example endspaces=" ">
        <pre xml:space="preserve">
          Then plainly know my heart's dear love is set \\ On the fair daughter of rich Capulet.
        </pre>
      </example>
      <findex index="fn" spaces=" ">
        <indexterm index="fn" number="460" mergedindex="cp">
          \\
          <r>
            (for
            <code>
              verse
            </code>
            )
          </r>
        </indexterm>
      </findex>
      <para>
        Separate the lines of each stanza with
        <code>
          \\
        </code>
        , and use one or more blank lines to separate the stanzas.
      </para>
      <example endspaces=" ">
        <pre xml:space="preserve">
          \begin
Default handler: &lbrace;
          verse
Default handler: &rbrace;
           \makebox[\linewidth][c]
Default handler: &lbrace;
          \textit
Default handler: &lbrace;
          Shut Not Your Doors
Default handler: &rbrace;
           ---Walt Whitman
Default handler: &rbrace;
           \\[1\baselineskip] Shut not your doors to me proud libraries, \\ For that which was lacking on all your well-fill'd shelves, \\ \qquad yet needed most, I bring, \\ Forth from the war emerging, a book I have made, \\ The words of my book nothing, the drift of it every thing, \\ A book separate, not link'd with the rest nor felt by the intellect, \\ But you ye untold latencies will thrill to every page. \end
Default handler: &lbrace;
          verse
Default handler: &rbrace;
        </pre>
      </example>
      <noindent/>
      <para>
        The output has margins indented on the left and the right, paragraphs are not indented, and the text is not right-justified.
      </para>
    </section>
  </chapter>
  <node name="Line-breaking" spaces=" ">
    <nodename>
      Line breaking
    </nodename>
    <nodenext automatic="on">
      Page breaking
    </nodenext>
    <nodeprev automatic="on">
      Environments
    </nodeprev>
    <nodeup automatic="on">
      Top
    </nodeup>
  </node>
  <chapter spaces=" ">
    <sectiontitle>
      Line breaking
    </sectiontitle>
    <cindex index="cp" spaces=" ">
      <indexterm index="cp" number="454">
        line breaking
      </indexterm>
    </cindex>
    <cindex index="cp" spaces=" ">
      <indexterm index="cp" number="455">
        breaking lines
      </indexterm>
    </cindex>
    <para>
      The first thing
Default handler: &latex;
       does when processing ordinary text is to translate your input file into a sequence of glyphs and spaces. To produce a printed document, this sequence must be broken into lines (and these lines must be broken into pages).
    </para>
    <paraDefault handler: &latex;
>
       usually does the line (and page) breaking in the text body for you but in some environments you manually force line breaks.
    </para>
    <para>
      A common workflow is to get a final version of the document content before taking a final pass through and considering line breaks (and page breaks). This differs from word processing, where you are formatting text as you input it. Putting these off until the end prevents a lot of fiddling with breaks that will change anyway.
Default handler: <!-- c Alernative text proposed here: https://tug.org/pipermail/latexrefman/2021q3/000803.html -->
Default handler: <!-- c this text is that of the French version. -->
      <ignore endspaces=" ">
         A common workflow with LaTeX is to get a final version of the document content before taking a final pass through and considering line breaks (and page breaks). Most people do not consider LaTeX as a word processor, because it does not show the output instantly. However differing the output encourages the user to put off until the end formatting adjustments, and thus it prevents a lot of fiddling with breaks that will change anyway. @noindent Differing the output has other advantages: it enables to make no compromise about the typesetting, which ensures that what you see it exactly what you get, and it also helps authors concentrate their mind on either writing or reading rather than distract it by doing both a the same time.
      </ignore>
    </para>
    <menu endspaces=" ">
      <menuentry>
        <menuleadingtext>
          *
        </menuleadingtext>
        <menunode>
          \\
        </menunode>
        <menuseparator>
          ::
        </menuseparator>
        <menudescription>
          <pre xml:space="preserve">
            Start a new line.
          </pre>
        </menudescription>
      </menuentry>
      <menuentry>
        <menuleadingtext>
          *
        </menuleadingtext>
        <menunode>
          \obeycr
          &
           \restorecr
        </menunode>
        <menuseparator>
          ::
        </menuseparator>
        <menudescription>
          <pre xml:space="preserve">
            Make each input line start a new output line.
          </pre>
        </menudescription>
      </menuentry>
      <menuentry>
        <menuleadingtext>
          *
        </menuleadingtext>
        <menunode>
          \newline
        </menunode>
        <menuseparator>
          ::
        </menuseparator>
        <menudescription>
          <pre xml:space="preserve">
            Break the line
          </pre>
        </menudescription>
      </menuentry>
      <menuentry>
        <menuleadingtext>
          *
        </menuleadingtext>
        <menunode>
          \- (hyphenation)
        </menunode>
        <menuseparator>
          ::
        </menuseparator>
        <menudescription>
          <pre xml:space="preserve">
            Insert explicit hyphenation.
          </pre>
        </menudescription>
      </menuentry>
      <menuentry>
        <menuleadingtext>
          *
        </menuleadingtext>
        <menunode>
          \slash
        </menunode>
        <menuseparator>
          ::
        </menuseparator>
        <menudescription>
          <pre xml:space="preserve">
            Insert a breakable /.
          </pre>
        </menudescription>
      </menuentry>
      <menuentry>
        <menuleadingtext>
          *
        </menuleadingtext>
        <menunode>
          \discretionary
        </menunode>
        <menuseparator>
          ::
        </menuseparator>
        <menudescription>
          <pre xml:space="preserve">
            Explicit control of hyphenation character(s).
          </pre>
        </menudescription>
      </menuentry>
      <menuentry>
        <menuleadingtext>
          *
        </menuleadingtext>
        <menunode>
          \fussy
          &
           \sloppy
        </menunode>
        <menuseparator>
          ::
        </menuseparator>
        <menudescription>
          <pre xml:space="preserve">
            Be more or less particular with line breaking.
          </pre>
        </menudescription>
      </menuentry>
      <menuentry>
        <menuleadingtext>
          *
        </menuleadingtext>
        <menunode>
          \hyphenation
        </menunode>
        <menuseparator>
          ::
        </menuseparator>
        <menudescription>
          <pre xml:space="preserve">
            Tell
Default handler: &latex;
             how to hyphenate a word.
          </pre>
        </menudescription>
      </menuentry>
      <menuentry>
        <menuleadingtext>
          *
        </menuleadingtext>
        <menunode>
          \linebreak
          &
           \nolinebreak
        </menunode>
        <menuseparator>
          ::
        </menuseparator>
        <menudescription>
          <pre xml:space="preserve">
            Forcing
            &
             avoiding line breaks.
          </pre>
        </menudescription>
      </menuentry>
    </menu>
    <node name="_005c_005c" spaces=" ">
      <nodename>
        \\
      </nodename>
      <nodenext automatic="on">
        \obeycr
        &
         \restorecr
      </nodenext>
      <nodeup automatic="on">
        Line breaking
      </nodeup>
    </node>
    <section spaces=" ">
      <sectiontitle>
        <code>
          \\
        </code>
      </sectiontitle>
      <findex index="fn" spaces=" ">
        <indexterm index="fn" number="461" mergedindex="cp">
          \\
          <r>
            (force line break)
          </r>
        </indexterm>
      </findex>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="456">
          new line, starting
        </indexterm>
      </cindex>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="457">
          line break, forcing
        </indexterm>
      </cindex>
      <para>
        Synopsis, one of:
      </para>
      <example endspaces=" ">
        <pre xml:space="preserve">
          \\ \\[
          <var>
            morespace
          </var>
          ]
        </pre>
      </example>
      <noindent/>
      <para>
        or one of:
      </para>
      <example endspaces=" ">
        <pre xml:space="preserve">
          \\* \\*[
          <var>
            morespace
          </var>
          ]
        </pre>
      </example>
      <para>
        End the current line. The optional argument
        <var>
          morespace
        </var>
         specifies extra vertical space to be inserted before the next line. This is a rubber length (
        <pxref label="Lengths">
          <xrefnodename>
            Lengths
          </xrefnodename>
        </pxref>
        ) and can be negative. The text before the line break is set at its normal length, that is, it is not stretched to fill out the line width. This command is fragile (
        <pxref label="_005cprotect">
          <xrefnodename>
            \protect
          </xrefnodename>
        </pxref>
        ).
      </para>
      <example endspaces=" ">
        <pre xml:space="preserve">
          \title
Default handler: &lbrace;
          My story: \\[0.25in] a tale of woe
Default handler: &rbrace;
        </pre>
      </example>
      <noindent/>
      <para>
        The starred form,
        <code>
          \\*
        </code>
        , tells
Default handler: &latex;
         not to start a new page between the two lines, by issuing a
        <code>
          \nobreak
        </code>
        .
      </para>
      <para>
        Explicit line breaks in the main text body are unusual in
Default handler: &latex;
        . In particular, don
Default handler: &textrsquo;
        t start new paragraphs with
        <code>
          \\
        </code>
        . Instead leave a blank line between the two paragraphs. And don
Default handler: &textrsquo;
        t put in a sequence of
        <code>
          \\
        </code>
Default handler: &textrsquo;
        s to make vertical space. Instead use
        <code>
          \vspace
Default handler: &lbrace;
          <var>
            length
          </var>
Default handler: &rbrace;
        </code>
        , or
        <code>
          \leavevmode\vspace
Default handler: &lbrace;
          <var>
            length
          </var>
Default handler: &rbrace;
        </code>
        , or
        <code>
          \vspace*
Default handler: &lbrace;
          <var>
            length
          </var>
Default handler: &rbrace;
        </code>
         if you want the space to not be thrown out at the top of a new page (
        <pxref label="_005cvspace">
          <xrefnodename>
            \vspace
          </xrefnodename>
        </pxref>
        ).
      </para>
      <para>
        The
        <code>
          \\
        </code>
         command is mostly used outside of the main flow of text such as in a
        <code>
          tabular
        </code>
         or
        <code>
          array
        </code>
         environment or in an equation environment.
      </para>
      <para>
        The
        <code>
          \\
        </code>
         command is a synonym for
        <code>
          \newline
        </code>
         (
        <pxref label="_005cnewline">
          <xrefnodename>
            \newline
          </xrefnodename>
        </pxref>
        ) under ordinary circumstances (an example of an exception is the
        <code>
          p
Default handler: &lbrace;
          ...
Default handler: &rbrace;
        </code>
         column in a
        <code>
          tabular
        </code>
         environment;
        <pxref label="tabular">
          <xrefnodename>
            tabular
          </xrefnodename>
        </pxref>
        ).
      </para>
Default handler: <!-- c credit: David Carlisle https://tex.stackexchange.com/a/82666 -->
      <para>
        The
        <code>
          \\
        </code>
         command is a macro, and its definition changes by context so that its definition in normal text, a
        <code>
          center
        </code>
         environment, a
        <code>
          flushleft
        </code>
         environment, and a
        <code>
          tabular
        </code>
         are all different. In normal text when it forces a linebreak it is essentially a shorthand for
        <code>
          \newline
        </code>
        . It does not end horizontal mode or end the paragraph, it just inserts some glue and penalties so that when the paragraph does end a linebreak will occur at that point, with the short line padded with white space.
      </para>
      <para>
        You get
        <samp>
          LaTeX Error: There's no line here to end
        </samp>
         if you use
        <code>
          \\
        </code>
         to ask for a new line, rather than to end the current line. An example is if you have
        <code>
          \begin
Default handler: &lbrace;
          document
Default handler: &rbrace;
          \\
        </code>
         or, more likely, something like this.
      </para>
      <example endspaces=" ">
        <pre xml:space="preserve">
          \begin
Default handler: &lbrace;
          center
Default handler: &rbrace;
           \begin
Default handler: &lbrace;
          minipage
Default handler: &rbrace;
Default handler: &lbrace;
          0.5\textwidth
Default handler: &rbrace;
           \\ In that vertical space put your mark. \end
Default handler: &lbrace;
          minipage
Default handler: &rbrace;
           \end
Default handler: &lbrace;
          center
Default handler: &rbrace;
        </pre>
      </example>
      <noindent/>
      <para>
        Fix it by replacing the double backslash with something like
        <code>
          \vspace
Default handler: &lbrace;
          \baselineskip
Default handler: &rbrace;
        </code>
        .
      </para>
    </section>
    <node name="_005cobeycr-_0026-_005crestorecr" spaces=" ">
      <nodename>
        \obeycr
        &
         \restorecr
      </nodename>
      <nodenext automatic="on">
        \newline
      </nodenext>
      <nodeprev automatic="on">
        \\
      </nodeprev>
      <nodeup automatic="on">
        Line breaking
      </nodeup>
    </node>
    <section spaces=" ">
      <sectiontitle>
        <code>
          \obeycr
        </code>
        &
        <code>
          \restorecr
        </code>
      </sectiontitle>
      <anchor name="_005cobeycr">
        \obeycr
      </anchor>
      <anchor name="_005crestorecr">
        \restorecr
      </anchor>
      <findex index="fn" spaces=" ">
        <indexterm index="fn" number="462" mergedindex="cp">
          \obeycr
        </indexterm>
      </findex>
      <findex index="fn" spaces=" ">
        <indexterm index="fn" number="463" mergedindex="cp">
          \restorecr
        </indexterm>
      </findex>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="458">
          new line, output as input
        </indexterm>
      </cindex>
      <para>
        The
        <code>
          \obeycr
        </code>
         command makes a return in the input file (
        <samp>
          ^^M
        </samp>
        , internally) the same as
        <code>
          \\
        </code>
        , followed by
        <code>
          \relax
        </code>
        . So each new line in the input will also be a new line in the output. The
        <code>
          \restorecr
        </code>
         command restores normal line-breaking behavior.
      </para>
      <para>
        This is not the way to show verbatim text or computer code. Use
        <code>
          verbatim
        </code>
         (
        <pxref label="verbatim">
          <xrefnodename>
            verbatim
          </xrefnodename>
        </pxref>
        ) instead.
      </para>
      <para>
        With
Default handler: &latex;
Default handler: &textrsquo;
        s usual defaults, this
      </para>
      <example endspaces=" ">
        <pre xml:space="preserve">
          aaa bbb \obeycr ccc ddd eee \restorecr fff ggg hhh iii
        </pre>
      </example>
      <noindent/>
      <para>
        produces output like this.
      </para>
      <example endspaces=" ">
        <pre xml:space="preserve">
           aaa bbb ccc ddd eee fff ggg hhh iii
        </pre>
      </example>
      <noindent/>
      <para>
        The indents are paragraph indents.
      </para>
    </section>
    <node name="_005cnewline" spaces=" ">
      <nodename>
        \newline
      </nodename>
      <nodenext automatic="on">
        \- (hyphenation)
      </nodenext>
      <nodeprev automatic="on">
        \obeycr
        &
         \restorecr
      </nodeprev>
      <nodeup automatic="on">
        Line breaking
      </nodeup>
    </node>
    <section spaces=" ">
      <sectiontitle>
        <code>
          \newline
        </code>
      </sectiontitle>
      <findex index="fn" spaces=" ">
        <indexterm index="fn" number="464" mergedindex="cp">
          \newline
        </indexterm>
      </findex>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="459">
          new line, starting (paragraph mode)
        </indexterm>
      </cindex>
      <para>
        In ordinary text, this ends a line in a way that does not right-justify it, so the text before the end of line is not stretched. That is, in paragraph mode (
        <pxref label="Modes">
          <xrefnodename>
            Modes
          </xrefnodename>
        </pxref>
        ), the
        <code>
          \newline
        </code>
         command is equivalent to double-backslash (
        <pxref label="_005c_005c">
          <xrefnodename>
            \\
          </xrefnodename>
        </pxref>
        ). This command is fragile (
        <pxref label="_005cprotect">
          <xrefnodename>
            \protect
          </xrefnodename>
        </pxref>
        ).
      </para>
      <para>
        However, the two commands are different inside a
        <code>
          tabular
        </code>
         or
        <code>
          array
        </code>
         environment. In a column with a specifier producing a paragraph box such as typically
        <code>
          p
Default handler: &lbrace;
          ...
Default handler: &rbrace;
        </code>
        ,
        <code>
          \newline
        </code>
         will insert a line end inside of the column; that is, it does not break the entire tabular row. To break the entire row use
        <code>
          \\
        </code>
         or its equivalent
        <code>
          \tabularnewline
        </code>
        .
      </para>
      <para>
        This will print
        <samp>
          Name:
        </samp>
         and
        <samp>
          Address:
        </samp>
         as two lines in a single cell of the table.
      </para>
      <example endspaces=" ">
        <pre xml:space="preserve">
          \begin
Default handler: &lbrace;
          tabular
Default handler: &rbrace;
Default handler: &lbrace;
          p
Default handler: &lbrace;
          1in
Default handler: &rbrace;
Default handler: &arobase;
Default handler: &lbrace;
          \hspace
Default handler: &lbrace;
          2in
Default handler: &rbrace;
Default handler: &rbrace;
          p
Default handler: &lbrace;
          1in
Default handler: &rbrace;
Default handler: &rbrace;
           Name: \newline Address:
          &
          Date: \\ \hline \end
Default handler: &lbrace;
          tabular
Default handler: &rbrace;
        </pre>
      </example>
      <noindent/>
      <para>
        The
        <samp>
          Date:
        </samp>
         will be baseline-aligned with
        <samp>
          Name:
        </samp>
        .
      </para>
    </section>
    <node name="_005c_002d-_0028hyphenation_0029" spaces=" ">
      <nodename>
        \- (hyphenation)
      </nodename>
      <nodenext automatic="on">
        \slash
      </nodenext>
      <nodeprev automatic="on">
        \newline
      </nodeprev>
      <nodeup automatic="on">
        Line breaking
      </nodeup>
    </node>
    <section spaces=" ">
      <sectiontitle>
        <code>
          \-
        </code>
         (discretionary hyphen)
      </sectiontitle>
      <findex index="fn" spaces=" ">
        <indexterm index="fn" number="465" mergedindex="cp">
          \-
          <r>
            (hyphenation)
          </r>
        </indexterm>
      </findex>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="460">
          hyphenation, forcing
        </indexterm>
      </cindex>
      <para>
        Tell
Default handler: &latex;
         that it may hyphenate the word at that point. When you insert
        <code>
          \-
        </code>
         commands in a word, the word will only be hyphenated at those points and not at any of the other hyphenation points that
Default handler: &latex;
         might otherwise have chosen. This command is robust (
        <pxref label="_005cprotect">
          <xrefnodename>
            \protect
          </xrefnodename>
        </pxref>
        ).
      </para>
      <paraDefault handler: &latex;
>
         is good at hyphenating and usually finds most of the correct hyphenation points, while almost never using an incorrect one. The
        <code>
          \-
        </code>
         command is for exceptional cases.
      </para>
      <para>
        For example,
Default handler: &latex;
         does not ordinarily hyphenate words containing a hyphen. Below, the long and hyphenated word means
Default handler: &latex;
         has to put in unacceptably large spaces to set the narrow column.
      </para>
      <example endspaces=" ">
        <pre xml:space="preserve">
          \begin
Default handler: &lbrace;
          tabular
Default handler: &rbrace;
Default handler: &lbrace;
          rp
Default handler: &lbrace;
          1.75in
Default handler: &rbrace;
Default handler: &rbrace;
           Isaac Asimov
          &
          The strain of anti-intellectualism % an\-ti-in\-tel\-lec\-tu\-al\-ism has been a constant thread winding its way through our political and cultural life, nurtured by the false notion that democracy means that `my ignorance is just as good as your knowledge'. \end
Default handler: &lbrace;
          tabular
Default handler: &rbrace;
        </pre>
      </example>
      <noindent/>
      <para>
        Commenting out the third line and uncommenting the fourth makes a much better fit.
      </para>
      <para>
        The
        <code>
          \-
        </code>
         command only allows
Default handler: &latex;
         to break there, it does not require that it break there. You can force a split with something like
        <code>
          Hef-\linebreak feron
        </code>
        . Of course, if you later change the text then this forced break may look out of place, so this approach requires care.
      </para>
    </section>
    <node name="_005cslash" spaces=" ">
      <nodename>
        \slash
      </nodename>
      <nodenext automatic="on">
        \discretionary
      </nodenext>
      <nodeprev automatic="on">
        \- (hyphenation)
      </nodeprev>
      <nodeup automatic="on">
        Line breaking
      </nodeup>
    </node>
    <section spaces=" ">
      <sectiontitle>
        <code>
          \slash
        </code>
        : breakable
        <samp>
          /
        </samp>
      </sectiontitle>
      <findex index="fn" spaces=" ">
        <indexterm index="fn" number="466" mergedindex="cp">
          \slash
        </indexterm>
      </findex>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="461">
          slash character, breakable
        </indexterm>
      </cindex>
      <para>
        The
        <code>
          \slash
        </code>
         command produces a
        <samp>
          /
        </samp>
         character and then a penalty of the same value as an explicit
        <samp>
          -
        </samp>
         character (
        <code>
          \exhyphenpenalty
        </code>
        ). This allows
Default handler: &tex;
         to break a line at the
        <samp>
          /
        </samp>
        , similar to a hyphen. Hyphenation is allowed in the word part preceding the
        <samp>
          /
        </samp>
        , but not after. For example:
      </para>
      <example endspaces=" ">
        <pre xml:space="preserve">
          The input\slash output of the program is complicated.
        </pre>
      </example>
    </section>
    <node name="_005cdiscretionary" spaces=" ">
      <nodename>
        \discretionary
      </nodename>
      <nodenext automatic="on">
        \fussy
        &
         \sloppy
      </nodenext>
      <nodeprev automatic="on">
        \slash
      </nodeprev>
      <nodeup automatic="on">
        Line breaking
      </nodeup>
    </node>
    <section spaces=" ">
      <sectiontitle>
        <code>
          \discretionary
        </code>
         (generalized hyphenation point)
      </sectiontitle>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="462">
          hyphenation, discretionary
        </indexterm>
      </cindex>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="463">
          discretionary hyphenation
        </indexterm>
      </cindex>
      <para>
        Synopsis:
      </para>
      <example endspaces=" ">
        <pre xml:space="preserve">
          \discretionary
Default handler: &lbrace;
          <var>
            pre-break
          </var>
Default handler: &rbrace;
Default handler: &lbrace;
          <var>
            post-break
          </var>
Default handler: &rbrace;
Default handler: &lbrace;
          <var>
            no-break
          </var>
Default handler: &rbrace;
        </pre>
      </example>
      <para>
        Handle word changes around hyphens. This command is not often used in
Default handler: &latex;
         documents.
      </para>
      <para>
        If a line break occurs at the point where
        <code>
          \discretionary
        </code>
         appears then
Default handler: &tex;
         puts
        <var>
          pre-break
        </var>
         at the end of the current line and puts
        <var>
          post-break
        </var>
         at the start of the next line. If there is no line break here then
Default handler: &tex;
         puts
        <var>
          no-break
        </var>
        .
      </para>
      <para>
        In
        <samp>
          difficult
        </samp>
         the three letters
        <code>
          ffi
        </code>
         form a ligature. But
Default handler: &tex;
         can nonetheless break between the two
        <samp>
          f
        </samp>
Default handler: &textrsquo;
        s with this.
      </para>
      <example endspaces=" ">
        <pre xml:space="preserve">
          di\discretionary
Default handler: &lbrace;
          f-
Default handler: &rbrace;
Default handler: &lbrace;
          fi
Default handler: &rbrace;
Default handler: &lbrace;
          ffi
Default handler: &rbrace;
          cult
        </pre>
      </example>
      <para>
        Note that users do not have to do this. It is typically handled automatically by
Default handler: &tex;
Default handler: &textrsquo;
        s hyphenation algorithm.
      </para>
Default handler: <!-- c xxx TODO, complete this node, see LaTeX-fr (copied & pasted below, -->
Default handler: <!-- c with accented letter escaped) -->
      <ignore endspaces=" ">
         @c Les arguments de @code{\discretionary} ne peuvent contenir que des @c caract@`eres, des bo@^{@dotless{i}}tes ou des cr@'enages. @c @c La commande @code{\discretionary} permet de contr@^oler @c finement la c@'esure dans les cas o@`u ne suffisent ni le contr@^ole standard @c de la c@'esure fait l'algorithme de c@'esure de @TeX{} et les r@`egles de @c c@'esures donn@'ees par les paquetages de gestion linguistiques, ni les @c moyens de contr@^ole explicites offerts par les commandes @c @code{\hyphenation} (@pxref{\hyphenation}) et @code{\-} (@pxref{\- @c (hyphenation),\- (c@'esure @`a gr@'e)}). @c @c L'usage typique de @code{\discretionary} est par exemple de contr@^oler la @c c@'esure au sein d'une formule math@'ematique en mode ligne (voir aussi @c @ref{Math miscellany,Miscellan@'ees math@'ematique (entr@'ee \*)}). Ci-dessous @c un exemple de contr@^ole de la c@'esure au sein d'une adresse r@'eticulaire, @c o@`u l'on autorise la c@'esure sur les obliques mais en utilisant une @c contr'oblique violette en lieu de trait d'union@tie{}: @c @c @example @c \documentclass@{article@} @c \usepackage[T1]@{fontenc@} @c \usepackage[utf8]@{inputenc@} @c \usepackage@{xcolor@} @c \usepackage@{hyperref@} @c \usepackage@{french@} @c \newcommand*\DiscrSlash@{\discretionary@{\mbox@{\textcolor @c @{purple@}@{\textbackslash@}@}@}@{/@}@{/@}@} @c \begin@{document@} @c Allez donc @`a \href@{http://une/tr\%c3\%A8s/tr\%c3\%A8s/longue% @c /mais/vraiment/tr\%c3\%A8s/longue/adresse/r\%C3\%A9ticulaire% @c /index.html@}@{http://une\DiscrSlash tr@`es\DiscrSlash tr@`es\DiscrSlash @c longue\DiscrSlash mais\DiscrSlash vraiment\DiscrSlash @c tr@`es\DiscrSlash longue\DiscrSlash adresse\DiscrSlash @c r@'eticulaire\DiscrSlash index.html@} @c \end@{document@} @c @end example
      </ignore>
    </section>
    <node name="_005cfussy-_0026-_005csloppy" spaces=" ">
      <nodename>
        \fussy
        &
         \sloppy
      </nodename>
      <nodenext automatic="on">
        \hyphenation
      </nodenext>
      <nodeprev automatic="on">
        \discretionary
      </nodeprev>
      <nodeup automatic="on">
        Line breaking
      </nodeup>
    </node>
    <section spaces=" ">
      <sectiontitle>
        <code>
          \fussy
        </code>
        &
        <code>
          \sloppy
        </code>
      </sectiontitle>
      <anchor name="_005cfussy">
        \fussy
      </anchor>
      <anchor name="_005csloppy">
        \sloppy
      </anchor>
      <findex index="fn" spaces=" ">
        <indexterm index="fn" number="467" mergedindex="cp">
          \fussy
        </indexterm>
      </findex>
      <findex index="fn" spaces=" ">
        <indexterm index="fn" number="468" mergedindex="cp">
          \sloppy
        </indexterm>
      </findex>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="464">
          line breaks, changing
        </indexterm>
      </cindex>
      <para>
        Declarations to make
Default handler: &tex;
         more picky or less picky about line breaking. Declaring
        <code>
          \fussy
        </code>
         usually avoids too much space between words, at the cost of an occasional overfull box. Conversely,
        <code>
          \sloppy
        </code>
         avoids overfull boxes while suffering loose interword spacing.
      </para>
      <para>
        The default is
        <code>
          \fussy
        </code>
        . Line breaking in a paragraph is controlled by whichever declaration is current at the end of the paragraph, i.e., at the blank line or
        <code>
          \par
        </code>
         or displayed equation ending that paragraph. So to affect the line breaks, include that paragraph-ending material in the scope of the command.
      </para>
      <menu endspaces=" ">
        <menuentry>
          <menuleadingtext>
            *
          </menuleadingtext>
          <menunode>
            sloppypar
          </menunode>
          <menuseparator>
            ::
          </menuseparator>
          <menudescription>
            <pre xml:space="preserve">
              Environment version of \sloppy command.
            </pre>
          </menudescription>
        </menuentry>
      </menu>
      <node name="sloppypar" spaces=" ">
        <nodename>
          sloppypar
        </nodename>
        <nodeup automatic="on">
          \fussy
          &
           \sloppy
        </nodeup>
      </node>
      <subsection spaces=" ">
        <sectiontitle>
          <code>
            sloppypar
          </code>
        </sectiontitle>
        <findex index="fn" spaces=" ">
          <indexterm index="fn" number="469" mergedindex="cp">
            <r>
              environment
            </r>
            ,
            <code>
              sloppypar
            </code>
          </indexterm>
        </findex>
        <findex index="fn" spaces=" ">
          <indexterm index="fn" number="470" mergedindex="cp">
            <code>
              sloppypar
            </code>
            <r>
              environment
            </r>
          </indexterm>
        </findex>
        <cindex index="cp" spaces=" ">
          <indexterm index="cp" number="465">
            sloppypar environment
          </indexterm>
        </cindex>
        <para>
          Synopsis:
        </para>
        <example endspaces=" ">
          <pre xml:space="preserve">
            \begin
Default handler: &lbrace;
            sloppypar
Default handler: &rbrace;
             ... paragraphs ... \end
Default handler: &lbrace;
            sloppypar
Default handler: &rbrace;
          </pre>
        </example>
        <para>
          Typeset the paragraphs with
          <code>
            \sloppy
          </code>
           in effect (
          <pxref label="_005cfussy-_0026-_005csloppy">
            <xrefnodename>
              \fussy
              &
               \sloppy
            </xrefnodename>
          </pxref>
          ). Use this to locally adjust line breaking, to avoid
          <samp>
            Overfull box
          </samp>
           or
          <samp>
            Underfull box
          </samp>
           errors.
        </para>
        <para>
          The example is simple.
        </para>
        <example endspaces=" ">
          <pre xml:space="preserve">
            \begin
Default handler: &lbrace;
            sloppypar
Default handler: &rbrace;
             Her plan for the morning thus settled, she sat quietly down to her book after breakfast, resolving to remain in the same place and the same employment till the clock struck one; and from habitude very little incommoded by the remarks and ejaculations of Mrs.\ Allen, whose vacancy of mind and incapacity for thinking were such, that as she never talked a great deal, so she could never be entirely silent; and, therefore, while she sat at her work, if she lost her needle or broke her thread, if she heard a carriage in the street, or saw a speck upon her gown, she must observe it aloud, whether there were anyone at leisure to answer her or not. \end
Default handler: &lbrace;
            sloppypar
Default handler: &rbrace;
          </pre>
        </example>
      </subsection>
    </section>
    <node name="_005chyphenation" spaces=" ">
      <nodename>
        \hyphenation
      </nodename>
      <nodenext automatic="on">
        \linebreak
        &
         \nolinebreak
      </nodenext>
      <nodeprev automatic="on">
        \fussy
        &
         \sloppy
      </nodeprev>
      <nodeup automatic="on">
        Line breaking
      </nodeup>
    </node>
    <section spaces=" ">
      <sectiontitle>
        <code>
          \hyphenation
        </code>
      </sectiontitle>
      <findex index="fn" spaces=" ">
        <indexterm index="fn" number="471" mergedindex="cp">
          \hyphenation
        </indexterm>
      </findex>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="466">
          hyphenation, defining
        </indexterm>
      </cindex>
      <para>
        Synopsis:
      </para>
      <example endspaces=" ">
        <pre xml:space="preserve">
          \hyphenation
Default handler: &lbrace;
          <var>
            word1
          </var>
           ...
Default handler: &rbrace;
        </pre>
      </example>
      <para>
        Declares allowed hyphenation points within the words in the list. The words in that list are separated by spaces. Show permitted points for hyphenation with an ASCII dash character,
        <code>
          -
        </code>
        .
      </para>
      <para>
        Here is an example:
      </para>
      <example endspaces=" ">
        <pre xml:space="preserve">
          \hyphenation
Default handler: &lbrace;
          hat-er il-lit-e-ra-ti tru-th-i-ness
Default handler: &rbrace;
        </pre>
      </example>
      <para>
        Use lowercase letters.
Default handler: &tex;
         will only hyphenate if the word matches exactly; no inflections are tried. Multiple
        <code>
          \hyphenation
        </code>
         commands accumulate.
      </para>
Default handler: <!-- c xx Re-align on LaTeX-fr which also mentions fontenc, and that -->
Default handler: <!-- c babel/polyglossia already load hyphenation patterns, and you have to -->
Default handler: <!-- c declare only non existing words. -->
    </section>
    <node name="_005clinebreak-_0026-_005cnolinebreak" spaces=" ">
      <nodename>
        \linebreak
        &
         \nolinebreak
      </nodename>
      <nodeprev automatic="on">
        \hyphenation
      </nodeprev>
      <nodeup automatic="on">
        Line breaking
      </nodeup>
    </node>
    <section spaces=" ">
      <sectiontitle>
        <code>
          \linebreak
        </code>
        &
        <code>
          \nolinebreak
        </code>
      </sectiontitle>
      <anchor name="_005clinebreak">
        \linebreak
      </anchor>
      <anchor name="_005cnolinebreak">
        \nolinebreak
      </anchor>
      <findex index="fn" spaces=" ">
        <indexterm index="fn" number="472" mergedindex="cp">
          \linebreak
        </indexterm>
      </findex>
      <findex index="fn" spaces=" ">
        <indexterm index="fn" number="473" mergedindex="cp">
          \nolinebreak
        </indexterm>
      </findex>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="467">
          line breaks, forcing
        </indexterm>
      </cindex>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="468">
          line breaks, preventing
        </indexterm>
      </cindex>
      <para>
        Synopses, one of:
      </para>
      <example endspaces=" ">
        <pre xml:space="preserve">
          \linebreak \linebreak[
          <var>
            zero-to-four
          </var>
          ]
        </pre>
      </example>
      <noindent/>
      <para>
        or one of these.
      </para>
      <example endspaces=" ">
        <pre xml:space="preserve">
          \nolinebreak \nolinebreak[
          <var>
            zero-to-four
          </var>
          ]
        </pre>
      </example>
      <para>
        Encourage or discourage a line break. The optional
        <var>
          zero-to-four
        </var>
         is an integer lying between 0 and 4 that allows you to soften the instruction. The default is 4, so that without the optional argument these commands entirely force or prevent the break. But for instance,
        <code>
          \nolinebreak[1]
        </code>
         is a suggestion that another place may be better. The higher the number, the more insistent the request. Both commands are fragile (
        <pxref label="_005cprotect">
          <xrefnodename>
            \protect
          </xrefnodename>
        </pxref>
        ).
      </para>
      <para>
        Here we tell
Default handler: &latex;
         that a good place to put a linebreak is after the standard legal text.
      </para>
      <example endspaces=" ">
        <pre xml:space="preserve">
          \boilerplatelegal
Default handler: &lbrace;
Default handler: &rbrace;
           \linebreak[2] We especially encourage applications from members of traditionally underrepresented groups.
        </pre>
      </example>
      <para>
        When you issue
        <code>
          \linebreak
        </code>
        , the spaces in the line are stretched out so that the break point reaches the right margin.
        <xref label="_005c_005c">
          <xrefnodename>
            \\
          </xrefnodename>
        </xref>
         and
Default handler: &nbsp;
        <ref label="_005cnewline">
          <xrefnodename>
            \newline
          </xrefnodename>
        </ref>
        , to have the spaces not stretched out.
      </para>
    </section>
  </chapter>
  <node name="Page-breaking" spaces=" ">
    <nodename>
      Page breaking
    </nodename>
    <nodenext automatic="on">
      Footnotes
    </nodenext>
    <nodeprev automatic="on">
      Line breaking
    </nodeprev>
    <nodeup automatic="on">
      Top
    </nodeup>
  </node>
  <chapter spaces=" ">
    <sectiontitle>
      Page breaking
    </sectiontitle>
    <cindex index="cp" spaces=" ">
      <indexterm index="cp" number="469">
        page breaking
      </indexterm>
    </cindex>
    <cindex index="cp" spaces=" ">
      <indexterm index="cp" number="470">
        breaking pages
      </indexterm>
    </cindex>
    <para>
      Ordinarily
Default handler: &latex;
       automatically takes care of breaking output into pages with its usual aplomb. But if you are writing commands, or tweaking the final version of a document, then you may need to understand how to influence its actions.
    </para>
Default handler: <!-- c credit: H Vogt https://tex.stackexchange.com/a/115563 -->
    <cindex index="cp" spaces=" ">
      <indexterm index="cp" number="471">
        badness
      </indexterm>
    </cindex>
    <paraDefault handler: &latex;
Default handler: &textrsquo;
>
      s algorithm for splitting a document into pages is more complex than just waiting until there is enough material to fill a page and outputting the result. Instead,
Default handler: &latex;
       typesets more material than would fit on the page and then chooses a break that is optimal in some way (it has the smallest
      <dfn>
        badness
      </dfn>
      ). An example of the advantage of this approach is that if the page has some vertical space that can be stretched or shrunk, such as with rubber lengths between paragraphs, then
Default handler: &latex;
       can use that to avoid widow lines (where a new page starts with the last line of a paragraph;
Default handler: &latex;
       can squeeze the extra line onto the first page) and orphans (where the first line of paragraph is at the end of a page;
Default handler: &latex;
       can stretch the material of the first page so the extra line falls on the second page). Another example is where
Default handler: &latex;
       uses available vertical shrinkage to fit on a page not just the header for a new section but also the first two lines of that section.
    </para>
    <para>
      But
Default handler: &latex;
       does not optimize over the entire document
Default handler: &textrsquo;
      s set of page breaks. So it can happen that the first page break is great but the second one is lousy; to break the current page
Default handler: &latex;
       doesn
Default handler: &textrsquo;
      t look as far ahead as the next page break. So occasionally you may want to influence page breaks while preparing a final version of a document.
    </para>
    <para>
      <xref label="Layout">
        <xrefnodename>
          Layout
        </xrefnodename>
      </xref>
      , for more material that is relevant to page breaking.
    </para>
    <menu endspaces=" ">
      <menuentry>
        <menuleadingtext>
          *
        </menuleadingtext>
        <menunode>
          \clearpage
          &
           \cleardoublepage
        </menunode>
        <menuseparator>
          ::
        </menuseparator>
        <menudescription>
          <pre xml:space="preserve">
            Start a new page; eject floats.
          </pre>
        </menudescription>
      </menuentry>
      <menuentry>
        <menuleadingtext>
          *
        </menuleadingtext>
        <menunode>
          \newpage
        </menunode>
        <menuseparator>
          ::
        </menuseparator>
        <menudescription>
          <pre xml:space="preserve">
            Start a new page.
          </pre>
        </menudescription>
      </menuentry>
      <menuentry>
        <menuleadingtext>
          *
        </menuleadingtext>
        <menunode>
          \enlargethispage
        </menunode>
        <menuseparator>
          ::
        </menuseparator>
        <menudescription>
          <pre xml:space="preserve">
            Enlarge the current page a bit.
          </pre>
        </menudescription>
      </menuentry>
      <menuentry>
        <menuleadingtext>
          *
        </menuleadingtext>
        <menunode>
          \pagebreak
          &
           \nopagebreak
        </menunode>
        <menuseparator>
          ::
        </menuseparator>
        <menudescription>
          <pre xml:space="preserve">
            Forcing
            &
             avoiding page breaks.
          </pre>
        </menudescription>
      </menuentry>
    </menu>
    <node name="_005cclearpage-_0026-_005ccleardoublepage" spaces=" ">
      <nodename>
        \clearpage
        &
         \cleardoublepage
      </nodename>
      <nodenext automatic="on">
        \newpage
      </nodenext>
      <nodeup automatic="on">
        Page breaking
      </nodeup>
    </node>
    <section spaces=" ">
      <sectiontitle>
        <code>
          \clearpage
        </code>
        &
        <code>
          \cleardoublepage
        </code>
      </sectiontitle>
      <anchor name="_005cclearpage">
        \clearpage
      </anchor>
      <findex index="fn" spaces=" ">
        <indexterm index="fn" number="474" mergedindex="cp">
          \clearpage
        </indexterm>
      </findex>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="472">
          flushing floats and starting a page
        </indexterm>
      </cindex>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="473">
          starting a new page and clearing floats
        </indexterm>
      </cindex>
      <anchor name="_005ccleardoublepage">
        \cleardoublepage
      </anchor>
      <findex index="fn" spaces=" ">
        <indexterm index="fn" number="475" mergedindex="cp">
          \cleardoublepage
        </indexterm>
      </findex>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="474">
          starting on a right-hand page
        </indexterm>
      </cindex>
      <para>
        Synopsis:
      </para>
      <example endspaces=" ">
        <pre xml:space="preserve">
          \clearpage
        </pre>
      </example>
      <noindent/>
      <para>
        or
      </para>
      <example endspaces=" ">
        <pre xml:space="preserve">
          \cleardoublepage
        </pre>
      </example>
      <para>
        End the current page and output all of the pending floating figures and tables (
        <pxref label="Floats">
          <xrefnodename>
            Floats
          </xrefnodename>
        </pxref>
        ). If there are too many floats to fit on the page then
Default handler: &latex;
         will put in extra pages containing only floats. In two-sided printing,
        <code>
          \cleardoublepage
        </code>
         also makes the next page of content a right-hand page, an odd-numbered page, if necessary inserting a blank page. The
        <code>
          \clearpage
        </code>
         command is robust while
        <code>
          \cleardoublepage
        </code>
         is fragile (
        <pxref label="_005cprotect">
          <xrefnodename>
            \protect
          </xrefnodename>
        </pxref>
        ).
      </para>
      <paraDefault handler: &latex;
Default handler: &textrsquo;
>
        s page breaks are optimized so ordinarily you only use this command in a document body to polish the final version, or inside commands.
      </para>
Default handler: <!-- c credit: https://www.tex.ac.uk/FAQ-reallyblank.html -->
      <para>
        The
        <code>
          \cleardoublepage
        </code>
         command will put in a blank page, but it will have the running headers and footers. To get a really blank page, use this command.
      </para>
      <example endspaces=" ">
        <pre xml:space="preserve">
          \let\origdoublepage\cleardoublepage \newcommand
Default handler: &lbrace;
          \clearemptydoublepage
Default handler: &rbrace;
Default handler: &lbrace;
          % \clearpage
Default handler: &lbrace;
          \pagestyle
Default handler: &lbrace;
          empty
Default handler: &rbrace;
          \origdoublepage
Default handler: &rbrace;
          %
Default handler: &rbrace;
        </pre>
      </example>
      <noindent/>
      <para>
        If you want
Default handler: &latex;
Default handler: &textrsquo;
        s standard
        <code>
          \chapter
        </code>
         command to do this then add the line
        <code>
          \let\cleardoublepage\clearemptydoublepage
        </code>
        . (Of course this affects all uses of
        <code>
          \cleardoublepage
        </code>
        , not just the one in
        <code>
          \chapter
        </code>
        .)
      </para>
      <para>
        The command
        <code>
          \newpage
        </code>
         (
        <pxref label="_005cnewpage">
          <xrefnodename>
            \newpage
          </xrefnodename>
        </pxref>
        ) also ends the current page, but without clearing pending floats. And, if
Default handler: &latex;
         is in two-column mode then
        <code>
          \newpage
        </code>
         ends the current column while
        <code>
          \clearpage
        </code>
         and
        <code>
          \cleardoublepage
        </code>
         end the current page.
      </para>
    </section>
    <node name="_005cnewpage" spaces=" ">
      <nodename>
        \newpage
      </nodename>
      <nodenext automatic="on">
        \enlargethispage
      </nodenext>
      <nodeprev automatic="on">
        \clearpage
        &
         \cleardoublepage
      </nodeprev>
      <nodeup automatic="on">
        Page breaking
      </nodeup>
    </node>
    <section spaces=" ">
      <sectiontitle>
        <code>
          \newpage
        </code>
      </sectiontitle>
      <findex index="fn" spaces=" ">
        <indexterm index="fn" number="476" mergedindex="cp">
          \newpage
        </indexterm>
      </findex>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="475">
          new page, starting
        </indexterm>
      </cindex>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="476">
          starting a new page
        </indexterm>
      </cindex>
      <para>
        Synopsis:
      </para>
      <example endspaces=" ">
        <pre xml:space="preserve">
          \newpage
        </pre>
      </example>
      <para>
        End the current page. This command is robust (
        <pxref label="_005cprotect">
          <xrefnodename>
            \protect
          </xrefnodename>
        </pxref>
        ).
      </para>
      <paraDefault handler: &latex;
Default handler: &textrsquo;
>
        s page breaks are optimized so ordinarily you only use this command in a document body to polish the final version, or inside commands.
      </para>
      <para>
        While the commands
        <code>
          \clearpage
        </code>
         and
        <code>
          \cleardoublepage
        </code>
         also end the current page, in addition they clear pending floats (
        <pxref label="_005cclearpage-_0026-_005ccleardoublepage">
          <xrefnodename>
            \clearpage
            &
             \cleardoublepage
          </xrefnodename>
        </pxref>
        ). And, if
Default handler: &latex;
         is in two-column mode then
        <code>
          \clearpage
        </code>
         and
        <code>
          \cleardoublepage
        </code>
         end the current page, possibly leaving an empty column, while
        <code>
          \newpage
        </code>
         only ends the current column.
      </para>
      <para>
        In contrast with
        <code>
          \pagebreak
        </code>
         (
        <pxref label="_005cpagebreak-_0026-_005cnopagebreak">
          <xrefnodename>
            \pagebreak
            &
             \nopagebreak
          </xrefnodename>
        </pxref>
        ), the
        <code>
          \newpage
        </code>
         command will cause the new page to start right where requested. This
      </para>
      <example endspaces=" ">
        <pre xml:space="preserve">
          Four score and seven years ago our fathers brought forth on this continent, \newpage \noindent a new nation, conceived in Liberty, and dedicated to the proposition that all men are created equal.
        </pre>
      </example>
      <noindent/>
      <para>
        makes a new page start after
        <samp>
          continent
        </samp>
        , and the cut-off line is not right justified. In addition,
        <code>
          \newpage
        </code>
         does not vertically stretch out the page, as
        <code>
          \pagebreak
        </code>
         does.
      </para>
    </section>
    <node name="_005cenlargethispage" spaces=" ">
      <nodename>
        \enlargethispage
      </nodename>
      <nodenext automatic="on">
        \pagebreak
        &
         \nopagebreak
      </nodenext>
      <nodeprev automatic="on">
        \newpage
      </nodeprev>
      <nodeup automatic="on">
        Page breaking
      </nodeup>
    </node>
    <section spaces=" ">
      <sectiontitle>
        <code>
          \enlargethispage
        </code>
      </sectiontitle>
      <findex index="fn" spaces=" ">
        <indexterm index="fn" number="477" mergedindex="cp">
          \enlargethispage
        </indexterm>
      </findex>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="477">
          enlarge current page
        </indexterm>
      </cindex>
      <para>
        Synopsis, one of:
      </para>
      <example endspaces=" ">
        <pre xml:space="preserve">
          \enlargethispage
Default handler: &lbrace;
          <var>
            size
          </var>
Default handler: &rbrace;
           \enlargethispage*
Default handler: &lbrace;
          <var>
            size
          </var>
Default handler: &rbrace;
        </pre>
      </example>
      <para>
        Enlarge the
        <code>
          \textheight
        </code>
         for the current page. The required argument
        <var>
          size
        </var>
         must be a rigid length (
        <pxref label="Lengths">
          <xrefnodename>
            Lengths
          </xrefnodename>
        </pxref>
        ). It may be positive or negative. This command is fragile (
        <pxref label="_005cprotect">
          <xrefnodename>
            \protect
          </xrefnodename>
        </pxref>
        ).
      </para>
      <para>
        A common strategy is to wait until you have the final text of a document, and then pass through it tweaking line and page breaks. This command allows you some page size leeway.
      </para>
      <para>
        This will allow one extra line on the current page.
      </para>
      <example endspaces=" ">
        <pre xml:space="preserve">
          \enlargethispage
Default handler: &lbrace;
          \baselineskip
Default handler: &rbrace;
        </pre>
      </example>
      <para>
        The starred form
        <code>
          \enlargesthispage*
        </code>
         tries to squeeze the material together on the page as much as possible, for the common use case of getting one more line on the page. This is often used together with an explicit
        <code>
          \pagebreak
        </code>
        .
      </para>
    </section>
    <node name="_005cpagebreak-_0026-_005cnopagebreak" spaces=" ">
      <nodename>
        \pagebreak
        &
         \nopagebreak
      </nodename>
      <nodeprev automatic="on">
        \enlargethispage
      </nodeprev>
      <nodeup automatic="on">
        Page breaking
      </nodeup>
    </node>
    <section spaces=" ">
      <sectiontitle>
        <code>
          \pagebreak
        </code>
        &
        <code>
          \nopagebreak
        </code>
      </sectiontitle>
      <anchor name="_005cpagebreak">
        \pagebreak
      </anchor>
      <anchor name="_005cnopagebreak">
        \nopagebreak
      </anchor>
      <findex index="fn" spaces=" ">
        <indexterm index="fn" number="478" mergedindex="cp">
          \pagebreak
        </indexterm>
      </findex>
      <findex index="fn" spaces=" ">
        <indexterm index="fn" number="479" mergedindex="cp">
          \nopagebreak
        </indexterm>
      </findex>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="478">
          page break, forcing
        </indexterm>
      </cindex>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="479">
          page break, preventing
        </indexterm>
      </cindex>
      <para>
        Synopses:
      </para>
      <example endspaces=" ">
        <pre xml:space="preserve">
          \pagebreak \pagebreak[
          <var>
            zero-to-four
          </var>
          ]
        </pre>
      </example>
      <noindent/>
      <para>
        or
      </para>
      <example endspaces=" ">
        <pre xml:space="preserve">
          \nopagebreak \nopagebreak[
          <var>
            zero-to-four
          </var>
          ]
        </pre>
      </example>
      <para>
        Encourage or discourage a page break. The optional
        <var>
          zero-to-four
        </var>
         is an integer that allows you to soften the request. The default is 4, so that without the optional argument these commands entirely force or prevent the break. But for instance
        <code>
          \nopagebreak[1]
        </code>
         suggests to
Default handler: &latex;
         that another spot might be preferable. The higher the number, the more insistent the request. Both commands are fragile (
        <pxref label="_005cprotect">
          <xrefnodename>
            \protect
          </xrefnodename>
        </pxref>
        ).
      </para>
      <paraDefault handler: &latex;
Default handler: &textrsquo;
>
        s page endings are optimized so ordinarily you only use these commands in a document body to polish the final version, or inside commands.
      </para>
      <para>
        If you use these inside a paragraph, they apply to the point following the line in which they appear. So this
      </para>
      <example endspaces=" ">
        <pre xml:space="preserve">
          Four score and seven years ago our fathers brought forth on this continent, \pagebreak a new nation, conceived in Liberty, and dedicated to the proposition that all men are created equal.
        </pre>
      </example>
      <noindent/>
      <para>
        does not give a page break at
        <samp>
          continent
        </samp>
        , but instead at
        <samp>
          nation
        </samp>
        , since that is where
Default handler: &latex;
         breaks that line. In addition, with
        <code>
          \pagebreak
        </code>
         the vertical space on the page is stretched out where possible so that it extends to the normal bottom margin. This can look strange, and if
        <code>
          \flushbottom
        </code>
         is in effect this can cause you to get
        <samp>
          Underfull \vbox (badness 10000) has occurred while \output is active
        </samp>
        .
        <xref label="_005cnewpage">
          <xrefnodename>
            \newpage
          </xrefnodename>
        </xref>
        , for a command that does not have these effects.
      </para>
      <findex index="fn" spaces=" ">
        <indexterm index="fn" number="480" mergedindex="cp">
          \samepage
        </indexterm>
      </findex>
      <findex index="fn" spaces=" ">
        <indexterm index="fn" number="481" mergedindex="cp">
          samepage
          <r>
            environment
          </r>
        </indexterm>
      </findex>
      <para>
        A declaration
        <code>
          \samepage
        </code>
         and corresponding
        <code>
          samepage
        </code>
         environment try to only allow breaks between paragraphs. They are not perfectly reliable. For more on keeping material on the same page, see the FAQ entry
        <url>
          <urefurl>
            https://texfaq.org/FAQ-nopagebrk
          </urefurl>
        </url>
        .)
      </para>
    </section>
  </chapter>
  <node name="Footnotes" spaces=" ">
    <nodename>
      Footnotes
    </nodename>
    <nodenext automatic="on">
      Definitions
    </nodenext>
    <nodeprev automatic="on">
      Page breaking
    </nodeprev>
    <nodeup automatic="on">
      Top
    </nodeup>
  </node>
  <chapter spaces=" ">
    <sectiontitle>
      Footnotes
    </sectiontitle>
    <cindex index="cp" spaces=" ">
      <indexterm index="cp" number="480">
        footnotes, creating
      </indexterm>
    </cindex>
    <para>
      Place a footnote at the bottom of the current page, as here.
    </para>
    <example endspaces=" ">
      <pre xml:space="preserve">
        No
        <accent type="uml">
          e
        </accent>
        l Coward quipped that having to read a footnote is like having to go downstairs to answer the door, while in the midst of making love.\footnote
Default handler: &lbrace;
        % I wouldn't know, I don't read footnotes.
Default handler: &rbrace;
      </pre>
    </example>
    <para>
      You can put multiple footnotes on a page. If the footnote text becomes too long then it will flow to the next page.
    </para>
    <para>
      You can also produce footnotes by combining the
      <code>
        \footnotemark
      </code>
       and the
      <code>
        \footnotetext
      </code>
       commands, which is useful in special circumstances.
    </para>
    <para>
      To make bibliographic references come out as footnotes you need to include a bibliographic style with that behavior (
      <pxref label="Using-BibTeX">
        <xrefnodename>
          Using BibTeX
        </xrefnodename>
      </pxref>
      ).
    </para>
    <menu endspaces=" ">
      <menuentry>
        <menuleadingtext>
          *
        </menuleadingtext>
        <menunode>
          \footnote
        </menunode>
        <menuseparator>
          ::
        </menuseparator>
        <menudescription>
          <pre xml:space="preserve">
            Insert a footnote.
          </pre>
        </menudescription>
      </menuentry>
      <menuentry>
        <menuleadingtext>
          *
        </menuleadingtext>
        <menunode>
          \footnotemark
        </menunode>
        <menuseparator>
          ::
        </menuseparator>
        <menudescription>
          <pre xml:space="preserve">
            Insert footnote mark only.
          </pre>
        </menudescription>
      </menuentry>
      <menuentry>
        <menuleadingtext>
          *
        </menuleadingtext>
        <menunode>
          \footnotetext
        </menunode>
        <menuseparator>
          ::
        </menuseparator>
        <menudescription>
          <pre xml:space="preserve">
            Insert footnote text only.
          </pre>
        </menudescription>
      </menuentry>
      <menuentry>
        <menuleadingtext>
          *
        </menuleadingtext>
        <menunode>
          Footnotes in section headings
        </menunode>
        <menuseparator>
          ::
        </menuseparator>
        <menudescription>
          <pre xml:space="preserve">
            Chapter or section titles.
          </pre>
        </menudescription>
      </menuentry>
      <menuentry>
        <menuleadingtext>
          *
        </menuleadingtext>
        <menunode>
          Footnotes in a table
        </menunode>
        <menuseparator>
          ::
        </menuseparator>
        <menudescription>
          <pre xml:space="preserve">
            Table footnotes.
          </pre>
        </menudescription>
      </menuentry>
      <menuentry>
        <menuleadingtext>
          *
        </menuleadingtext>
        <menunode>
          Footnotes of footnotes
        </menunode>
        <menuseparator>
          ::
        </menuseparator>
        <menudescription>
          <pre xml:space="preserve">
            Multiple classes of footnotes.
          </pre>
        </menudescription>
      </menuentry>
    </menu>
    <node name="_005cfootnote" spaces=" ">
      <nodename>
        \footnote
      </nodename>
      <nodenext automatic="on">
        \footnotemark
      </nodenext>
      <nodeup automatic="on">
        Footnotes
      </nodeup>
    </node>
    <section spaces=" ">
      <sectiontitle>
        <code>
          \footnote
        </code>
      </sectiontitle>
      <findex index="fn" spaces=" ">
        <indexterm index="fn" number="482" mergedindex="cp">
          \footnote
        </indexterm>
      </findex>
      <para>
        Synopsis, one of:
      </para>
      <example endspaces=" ">
        <pre xml:space="preserve">
          \footnote
Default handler: &lbrace;
          <var>
            text
          </var>
Default handler: &rbrace;
           \footnote[
          <var>
            number
          </var>
          ]
Default handler: &lbrace;
          <var>
            text
          </var>
Default handler: &rbrace;
        </pre>
      </example>
      <para>
        Place a footnote
        <var>
          text
        </var>
         at the bottom of the current page, with a footnote marker at the current position in the text.
      </para>
      <example endspaces=" ">
        <pre xml:space="preserve">
          There are over a thousand footnotes in Gibbon's \textit
Default handler: &lbrace;
          Decline and Fall of the Roman Empire
Default handler: &rbrace;
          .\footnote
Default handler: &lbrace;
          % After reading an early version with endnotes David Hume complained, ``One is also plagued with his Notes, according to the present Method of printing the Book'' and suggested that they ``only to be printed at the Margin or the Bottom of the Page.''
Default handler: &rbrace;
        </pre>
      </example>
      <para>
        The optional argument
        <var>
          number
        </var>
         allows you to specify the number of the footnote. If you use this then
Default handler: &latex;
         does not increment the
        <code>
          footnote
        </code>
         counter.
      </para>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="481">
          footnotes, symbols instead of numbers
        </indexterm>
      </cindex>
      <findex index="fn" spaces=" ">
        <indexterm index="fn" number="483" mergedindex="cp">
          \fnsymbol
          <r>
            , and footnotes
          </r>
        </indexterm>
      </findex>
      <findex index="fn" spaces=" ">
        <indexterm index="fn" number="484" mergedindex="cp">
          \
Default handler: &arobase;
          fnsymbol
        </indexterm>
      </findex>
      <para>
        By default,
Default handler: &latex;
         uses arabic numbers as footnote markers. Change this with something like
        <code>
          \renewcommand
Default handler: &lbrace;
          \thefootnote
Default handler: &rbrace;
Default handler: &lbrace;
          \fnsymbol
Default handler: &lbrace;
          footnote
Default handler: &rbrace;
Default handler: &rbrace;
        </code>
        , which uses a sequence of symbols (
        <pxref label="_005calph-_005cAlph-_005carabic-_005croman-_005cRoman-_005cfnsymbol">
          <xrefnodename>
            \alph \Alph \arabic \roman \Roman \fnsymbol
          </xrefnodename>
        </pxref>
        ). To make this change global put that in the preamble. If you make the change local then you may want to reset the counter with
        <code>
          \setcounter
Default handler: &lbrace;
          footnote
Default handler: &rbrace;
Default handler: &lbrace;
          0
Default handler: &rbrace;
        </code>
        .
      </para>
      <paraDefault handler: &latex;
>
         determines the spacing of footnotes with two parameters.
      </para>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="482">
          footnote parameters
        </indexterm>
      </cindex>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="483">
          parameters, for footnotes
        </indexterm>
      </cindex>
      <ftable commandarg="code" spaces=" " endspaces=" ">
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                <indexterm index="fn" number="485" mergedindex="cp">
                  \footnoterule
                </indexterm>
                \footnoterule
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <anchor name="footnote-footnoterule">
              footnote footnoterule
            </anchor>
            <para>
              Produces the rule separating the main text on a page from the page
Default handler: &textrsquo;
              s footnotes. Default dimensions in the standard document classes (except
              <code>
                slides
              </code>
              , where it does not appear) are: vertical thickness of
              <code>
                0.4pt
              </code>
              , and horizontal size of
              <code>
                0.4\columnwidth
              </code>
               long. Change the rule with something like this.
            </para>
Default handler: <!-- c Credit egreg: https://tex.stackexchange.com/a/21917 -->
            <example endspaces=" ">
              <pre xml:space="preserve">
                % \footnoterule is expanded in vertical mode, thus \kern % commands ensure that no vertical space is created, % and the rule is separated vertically with 2pt % above the note text. \renewcommand*
Default handler: &lbrace;
                \footnoterule
Default handler: &rbrace;
Default handler: &lbrace;
                % \kern -3pt % This -3 is negative \hrule width \textwidth height 1pt % of the sum of this 1 \kern 2pt
Default handler: &rbrace;
                 % and this 2
              </pre>
            </example>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                <indexterm index="fn" number="486" mergedindex="cp">
                  \footnotesep
                </indexterm>
                \footnotesep
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <anchor name="footnote-footnotesep">
              footnote footnotesep
            </anchor>
            <cindex index="cp" spaces=" ">
              <indexterm index="cp" number="484">
                strut
              </indexterm>
            </cindex>
            <para>
              The height of the strut placed at the beginning of the footnote (
              <pxref label="_005cstrut">
                <xrefnodename>
                  \strut
                </xrefnodename>
              </pxref>
              ). By default, this is set to the normal strut for
              <code>
                \footnotesize
              </code>
               fonts (
              <pxref label="Font-sizes">
                <xrefnodename>
                  Font sizes
                </xrefnodename>
              </pxref>
              ), therefore there is no extra space between footnotes. This is
              <samp>
                6.65pt
              </samp>
               for
              <samp>
                10pt
              </samp>
              ,
              <samp>
                7.7pt
              </samp>
               for
              <samp>
                11pt
              </samp>
              , and
              <samp>
                8.4pt
              </samp>
               for
              <samp>
                12pt
              </samp>
              . Change it as with
              <code>
                \setlength
Default handler: &lbrace;
                \footnotesep
Default handler: &rbrace;
Default handler: &lbrace;
                11pt
Default handler: &rbrace;
              </code>
              .
            </para>
          </tableitem>
        </tableentry>
      </ftable>
      <para>
        The
        <code>
          \footnote
        </code>
         command is fragile (
        <pxref label="_005cprotect">
          <xrefnodename>
            \protect
          </xrefnodename>
        </pxref>
        ).
      </para>
      <paraDefault handler: &latex;
Default handler: &textrsquo;
>
        s default puts many restrictions on where you can use a
        <code>
          \footnote
        </code>
        ; for instance, you cannot use it in an argument to a sectioning command such as
        <code>
          \chapter
        </code>
         (it can only be used in outer paragraph mode;
        <pxref label="Modes">
          <xrefnodename>
            Modes
          </xrefnodename>
        </pxref>
        ). There are some workarounds; see following sections.
      </para>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="485">
          footnotes, in a minipage
        </indexterm>
      </cindex>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="486">
          mpfootnote counter
        </indexterm>
      </cindex>
      <para>
        In a
        <code>
          minipage
        </code>
         environment the
        <code>
          \footnote
        </code>
         command uses the
        <code>
          mpfootnote
        </code>
         counter instead of the
        <code>
          footnote
        </code>
         counter, so they are numbered independently. They are shown at the bottom of the environment, not at the bottom of the page. And by default they are shown alphabetically.
        <xref label="minipage">
          <xrefnodename>
            minipage
          </xrefnodename>
        </xref>
         and
        <ref label="Footnotes-in-a-table">
          <xrefnodename>
            Footnotes in a table
          </xrefnodename>
        </ref>
        .
      </para>
    </section>
    <node name="_005cfootnotemark" spaces=" ">
      <nodename>
        \footnotemark
      </nodename>
      <nodenext automatic="on">
        \footnotetext
      </nodenext>
      <nodeprev automatic="on">
        \footnote
      </nodeprev>
      <nodeup automatic="on">
        Footnotes
      </nodeup>
    </node>
    <section spaces=" ">
      <sectiontitle>
        <code>
          \footnotemark
        </code>
      </sectiontitle>
      <findex index="fn" spaces=" ">
        <indexterm index="fn" number="487" mergedindex="cp">
          \footnotemark
        </indexterm>
      </findex>
      <para>
        Synopsis, one of:
      </para>
      <example endspaces=" ">
        <pre xml:space="preserve">
          \footnotemark \footnotemark[
          <var>
            number
          </var>
          ]
        </pre>
      </example>
      <para>
        Put the current footnote mark in the text. To specify associated text for the footnote see
Default handler: &nbsp;
        <ref label="_005cfootnotetext">
          <xrefnodename>
            \footnotetext
          </xrefnodename>
        </ref>
        . The optional argument
        <var>
          number
        </var>
         causes the command to use that number to determine the footnote mark. This command can be used in inner paragraph mode (
        <pxref label="Modes">
          <xrefnodename>
            Modes
          </xrefnodename>
        </pxref>
        ).
      </para>
      <para>
        If you use
        <code>
          \footnotemark
        </code>
         without the optional argument then it increments the
        <code>
          footnote
        </code>
         counter, but if you use the optional
        <var>
          number
        </var>
         then it does not. The next example produces several consecutive footnote markers referring to the same footnote.
      </para>
      <example endspaces=" ">
        <pre xml:space="preserve">
          The first theorem\footnote
Default handler: &lbrace;
          Due to Gauss.
Default handler: &rbrace;
           and the second theorem\footnotemark[\value
Default handler: &lbrace;
          footnote
Default handler: &rbrace;
          ] and the third theorem.\footnotemark[\value
Default handler: &lbrace;
          footnote
Default handler: &rbrace;
          ]
        </pre>
      </example>
      <para>
        If there are intervening footnotes then you must remember the value of the number of the common mark. This example gives the same institutional affiliation to both the first and third authors (
        <code>
          \thanks
        </code>
         is a version of
        <code>
          \footnote
        </code>
        ), by explicitly specifying the number of the footnote (
        <samp>
          1
        </samp>
        ).
      </para>
      <example endspaces=" ">
        <pre xml:space="preserve">
          \title
Default handler: &lbrace;
          A Treatise on the Binomial Theorem
Default handler: &rbrace;
           \author
Default handler: &lbrace;
          J Moriarty\thanks
Default handler: &lbrace;
          University of Leeds
Default handler: &rbrace;
           \and A C Doyle\thanks
Default handler: &lbrace;
          Durham University
Default handler: &rbrace;
           \and S Holmes\footnotemark[1]
Default handler: &rbrace;
           \begin
Default handler: &lbrace;
          document
Default handler: &rbrace;
           \maketitle
        </pre>
      </example>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="487">
          <r>
            package
          </r>
          ,
          <code>
            cleveref
          </code>
        </indexterm>
      </cindex>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="488">
          <code>
            cleveref
          </code>
          <r>
            package
          </r>
        </indexterm>
      </cindex>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="489">
          <r>
            package
          </r>
          ,
          <code>
            hyperref
          </code>
        </indexterm>
      </cindex>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="490">
          <code>
            hyperref
          </code>
          <r>
            package
          </r>
        </indexterm>
      </cindex>
      <para>
        This example accomplishes the same by using the package
        <code>
          cleveref
        </code>
        .
      </para>
Default handler: <!-- c from SE user Jake http://tex.stackexchange.com/a/10116/339 -->
      <example endspaces=" ">
        <pre xml:space="preserve">
          \usepackage
Default handler: &lbrace;
          cleveref
Default handler: &rbrace;
          [2012/02/15] % in preamble \crefformat
Default handler: &lbrace;
          footnote
Default handler: &rbrace;
Default handler: &lbrace;
          #2\footnotemark[#1]#3
Default handler: &rbrace;
           ... The theorem is from Evers.\footnote
Default handler: &lbrace;
          \label
Default handler: &lbrace;
          fn:TE
Default handler: &rbrace;
          Tinker, Evers, 1994.
Default handler: &rbrace;
           The corollary is from Chance.\footnote
Default handler: &lbrace;
          Evers, Chance, 1990.
Default handler: &rbrace;
           But the key lemma is from Tinker.\cref
Default handler: &lbrace;
          fn:TE
Default handler: &rbrace;
        </pre>
      </example>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="491">
          <r>
            package
          </r>
          ,
          <code>
            hyperref
          </code>
        </indexterm>
      </cindex>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="492">
          <code>
            hyperref
          </code>
          <r>
            package
          </r>
        </indexterm>
      </cindex>
      <para>
        It will work with the package
        <code>
          hyperref
        </code>
        .
      </para>
      <para>
        This uses a counter to remember the footnote number. The third sentence is followed by the same footnote marker as the first.
      </para>
      <example endspaces=" ">
        <pre xml:space="preserve">
          \newcounter
Default handler: &lbrace;
          footnoteValueSaver
Default handler: &rbrace;
           All babies are illogical.\footnote
Default handler: &lbrace;
          % Lewis Carroll.
Default handler: &rbrace;
          \setcounter
Default handler: &lbrace;
          footnoteValueSaver
Default handler: &rbrace;
Default handler: &lbrace;
          \value
Default handler: &lbrace;
          footnote
Default handler: &rbrace;
Default handler: &rbrace;
           Nobody is despised who can manage a crocodile.\footnote
Default handler: &lbrace;
          % Captain Hook.
Default handler: &rbrace;
           Illogical persons are despised.\footnotemark[\value
Default handler: &lbrace;
          footnoteValueSaver
Default handler: &rbrace;
          ] Therefore, anyone who can manage a crocodile is not a baby.
        </pre>
      </example>
    </section>
    <node name="_005cfootnotetext" spaces=" ">
      <nodename>
        \footnotetext
      </nodename>
      <nodenext automatic="on">
        Footnotes in section headings
      </nodenext>
      <nodeprev automatic="on">
        \footnotemark
      </nodeprev>
      <nodeup automatic="on">
        Footnotes
      </nodeup>
    </node>
    <section spaces=" ">
      <sectiontitle>
        <code>
          \footnotetext
        </code>
      </sectiontitle>
      <findex index="fn" spaces=" ">
        <indexterm index="fn" number="488" mergedindex="cp">
          \footnotetext
        </indexterm>
      </findex>
      <para>
        Synopsis, one of:
      </para>
      <example endspaces=" ">
        <pre xml:space="preserve">
          \footnotetext
Default handler: &lbrace;
          <var>
            text
          </var>
Default handler: &rbrace;
           \footnotetext[
          <var>
            number
          </var>
          ]
Default handler: &lbrace;
          <var>
            text
          </var>
Default handler: &rbrace;
        </pre>
      </example>
      <para>
        Place
        <var>
          text
        </var>
         at the bottom of the page as a footnote. It pairs with
        <code>
          \footnotemark
        </code>
         (
        <pxref label="_005cfootnotemark">
          <xrefnodename>
            \footnotemark
          </xrefnodename>
        </pxref>
        ) and can come anywhere after that command, but must appear in outer paragraph mode (
        <pxref label="Modes">
          <xrefnodename>
            Modes
          </xrefnodename>
        </pxref>
        ). The optional argument
        <var>
          number
        </var>
         changes the number of the footnote mark.
      </para>
      <para>
        <xref label="_005cfootnotemark">
          <xrefnodename>
            \footnotemark
          </xrefnodename>
        </xref>
         and
Default handler: &nbsp;
        <ref label="Footnotes-in-a-table">
          <xrefnodename>
            Footnotes in a table
          </xrefnodename>
        </ref>
        , for usage examples.
      </para>
    </section>
    <node name="Footnotes-in-section-headings" spaces=" ">
      <nodename>
        Footnotes in section headings
      </nodename>
      <nodenext automatic="on">
        Footnotes in a table
      </nodenext>
      <nodeprev automatic="on">
        \footnotetext
      </nodeprev>
      <nodeup automatic="on">
        Footnotes
      </nodeup>
    </node>
    <section spaces=" ">
      <sectiontitle>
        Footnotes in section headings
      </sectiontitle>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="493">
          footnote, in section headings
        </indexterm>
      </cindex>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="494">
          table of contents, avoiding footnotes
        </indexterm>
      </cindex>
      <para>
        Putting a footnote in a section heading, as in:
      </para>
      <example endspaces=" ">
        <pre xml:space="preserve">
          \section
Default handler: &lbrace;
          Full sets\protect\footnote
Default handler: &lbrace;
          This material due to ...
Default handler: &rbrace;
Default handler: &rbrace;
        </pre>
      </example>
      <noindent/>
      <para>
        causes the footnote to appear at the bottom of the page where the section starts, as usual, but also at the bottom of the table of contents, where it is not likely to be desired. The simplest way to have it not appear on the table of contents is to use the optional argument to
        <code>
          \section
        </code>
        .
Default handler: <!-- c xx Same issue with table/figure captions and -->
Default handler: <!-- c \listoftable/\listoffigures, and same sort of fix can be used. -->
      </para>
      <example endspaces=" ">
        <pre xml:space="preserve">
          \section[Please]
Default handler: &lbrace;
          Please\footnote
Default handler: &lbrace;
          % Don't footnote in chapter and section headers!
Default handler: &rbrace;
Default handler: &rbrace;
        </pre>
      </example>
      <noindent/>
      <para>
        No
        <code>
          \protect
        </code>
         is needed in front of
        <code>
          \footnote
        </code>
         here because what gets moved to the table of contents is the optional argument.
      </para>
    </section>
    <node name="Footnotes-in-a-table" spaces=" ">
      <nodename>
        Footnotes in a table
      </nodename>
      <nodenext automatic="on">
        Footnotes of footnotes
      </nodenext>
      <nodeprev automatic="on">
        Footnotes in section headings
      </nodeprev>
      <nodeup automatic="on">
        Footnotes
      </nodeup>
    </node>
    <section spaces=" ">
      <sectiontitle>
        Footnotes in a table
      </sectiontitle>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="495">
          footnote, in a table
        </indexterm>
      </cindex>
      <para>
        Inside a
        <code>
          tabular
        </code>
         or
        <code>
          array
        </code>
         environment the
        <code>
          \footnote
        </code>
         command does not work; there is a footnote mark in the table cell but the footnote text does not appear. The solution is to use a
        <code>
          minipage
        </code>
         environment as here (
        <pxref label="minipage">
          <xrefnodename>
            minipage
          </xrefnodename>
        </pxref>
        ).
      </para>
      <example endspaces=" ">
        <pre xml:space="preserve">
          \begin
Default handler: &lbrace;
          center
Default handler: &rbrace;
           \begin
Default handler: &lbrace;
          minipage
Default handler: &rbrace;
Default handler: &lbrace;
          \textwidth
Default handler: &rbrace;
           \centering \begin
Default handler: &lbrace;
          tabular
Default handler: &rbrace;
Default handler: &lbrace;
          l|l
Default handler: &rbrace;
           \textsc
Default handler: &lbrace;
          Ship
Default handler: &rbrace;
          &
          \textsc
Default handler: &lbrace;
          Book
Default handler: &rbrace;
           \\ \hline \textit
Default handler: &lbrace;
          HMS Sophie
Default handler: &rbrace;
          &
          Master and Commander \\ \textit
Default handler: &lbrace;
          HMS Polychrest
Default handler: &rbrace;
          &
          Post Captain \\ \textit
Default handler: &lbrace;
          HMS Lively
Default handler: &rbrace;
          &
          Post Captain \\ \textit
Default handler: &lbrace;
          HMS Surprise
Default handler: &rbrace;
          &
          A number of books\footnote
Default handler: &lbrace;
          % Starting with \textit
Default handler: &lbrace;
          HMS Surprise
Default handler: &rbrace;
          .
Default handler: &rbrace;
           \end
Default handler: &lbrace;
          tabular
Default handler: &rbrace;
           \end
Default handler: &lbrace;
          minipage
Default handler: &rbrace;
           \end
Default handler: &lbrace;
          center
Default handler: &rbrace;
        </pre>
      </example>
      <para>
        Inside a
        <code>
          minipage
        </code>
        , footnote marks are lowercase letters. Change that with something like
        <code>
          \renewcommand
Default handler: &lbrace;
          \thempfootnote
Default handler: &rbrace;
Default handler: &lbrace;
          \arabic
Default handler: &lbrace;
          mpfootnote
Default handler: &rbrace;
Default handler: &rbrace;
        </code>
         (
        <pxref label="_005calph-_005cAlph-_005carabic-_005croman-_005cRoman-_005cfnsymbol">
          <xrefnodename>
            \alph \Alph \arabic \roman \Roman \fnsymbol
          </xrefnodename>
        </pxref>
        ).
      </para>
      <para>
        The footnotes in the prior example appear at the bottom of the
        <code>
          minipage
        </code>
        . To have them appear at the bottom of the main page, as part of the regular footnote sequence, use the
        <code>
          \footnotemark
        </code>
         and
        <code>
          \footnotetext
        </code>
         pair and make a new counter.
      </para>
      <example endspaces=" ">
        <pre xml:space="preserve">
          \newcounter
Default handler: &lbrace;
          mpFootnoteValueSaver
Default handler: &rbrace;
           \begin
Default handler: &lbrace;
          center
Default handler: &rbrace;
           \begin
Default handler: &lbrace;
          minipage
Default handler: &rbrace;
Default handler: &lbrace;
          \textwidth
Default handler: &rbrace;
           \setcounter
Default handler: &lbrace;
          mpFootnoteValueSaver
Default handler: &rbrace;
Default handler: &lbrace;
          \value
Default handler: &lbrace;
          footnote
Default handler: &rbrace;
Default handler: &rbrace;
           \centering \begin
Default handler: &lbrace;
          tabular
Default handler: &rbrace;
Default handler: &lbrace;
          l|l
Default handler: &rbrace;
           \textsc
Default handler: &lbrace;
          Woman
Default handler: &rbrace;
          &
          \textsc
Default handler: &lbrace;
          Relationship
Default handler: &rbrace;
           \\ \hline Mona
          &
          Attached\footnotemark \\ Diana Villiers
          &
          Eventual wife \\ Christine Hatherleigh Wood
          &
          Fiance\footnotemark \end
Default handler: &lbrace;
          tabular
Default handler: &rbrace;
           \end
Default handler: &lbrace;
          minipage
Default handler: &rbrace;
          % percent sign keeps footnote text close to minipage \stepcounter
Default handler: &lbrace;
          mpFootnoteValueSaver
Default handler: &rbrace;
          % \footnotetext[\value
Default handler: &lbrace;
          mpFootnoteValueSaver
Default handler: &rbrace;
          ]
Default handler: &lbrace;
          % Little is known other than her death.
Default handler: &rbrace;
          % \stepcounter
Default handler: &lbrace;
          mpFootnoteValueSaver
Default handler: &rbrace;
          % \footnotetext[\value
Default handler: &lbrace;
          mpFootnoteValueSaver
Default handler: &rbrace;
          ]
Default handler: &lbrace;
          % Relationship is unresolved.
Default handler: &rbrace;
           \end
Default handler: &lbrace;
          center
Default handler: &rbrace;
        </pre>
      </example>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="496">
          <r>
            package
          </r>
          ,
          <code>
            tablefootnote
          </code>
        </indexterm>
      </cindex>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="497">
          <code>
            tablefootnote
          </code>
          <r>
            package
          </r>
        </indexterm>
      </cindex>
      <para>
        For a floating
        <code>
          table
        </code>
         environment (
        <pxref label="table">
          <xrefnodename>
            table
          </xrefnodename>
        </pxref>
        ), use the
        <code>
          tablefootnote
        </code>
         package.
      </para>
      <example endspaces=" ">
        <pre xml:space="preserve">
          \usepackage
Default handler: &lbrace;
          tablefootnote
Default handler: &rbrace;
           % in preamble ... \begin
Default handler: &lbrace;
          table
Default handler: &rbrace;
           \centering \begin
Default handler: &lbrace;
          tabular
Default handler: &rbrace;
Default handler: &lbrace;
          l|l
Default handler: &rbrace;
           \textsc
Default handler: &lbrace;
          Date
Default handler: &rbrace;
          &
          \textsc
Default handler: &lbrace;
          Campaign
Default handler: &rbrace;
           \\ \hline 1862
          &
          Fort Donelson \\ 1863
          &
          Vicksburg \\ 1865
          &
          Army of Northern Virginia\tablefootnote
Default handler: &lbrace;
          % Ending the war.
Default handler: &rbrace;
           \end
Default handler: &lbrace;
          tabular
Default handler: &rbrace;
           \caption
Default handler: &lbrace;
          Forces captured by US Grant
Default handler: &rbrace;
           \end
Default handler: &lbrace;
          table
Default handler: &rbrace;
        </pre>
      </example>
      <noindent/>
      <para>
        The footnote appears at the page bottom and is numbered in sequence with other footnotes.
      </para>
    </section>
    <node name="Footnotes-of-footnotes" spaces=" ">
      <nodename>
        Footnotes of footnotes
      </nodename>
      <nodeprev automatic="on">
        Footnotes in a table
      </nodeprev>
      <nodeup automatic="on">
        Footnotes
      </nodeup>
    </node>
    <section spaces=" ">
      <sectiontitle>
        Footnotes of footnotes
      </sectiontitle>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="498">
          footnote, of a footnote
        </indexterm>
      </cindex>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="499">
          <r>
            package
          </r>
          ,
          <code>
            bigfoot
          </code>
        </indexterm>
      </cindex>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="500">
          <code>
            bigfoot
          </code>
          <r>
            package
          </r>
        </indexterm>
      </cindex>
      <para>
        Particularly in the humanities, authors can have multiple classes of footnotes, including having footnotes of footnotes. The package
        <code>
          bigfoot
        </code>
         extends
Default handler: &latex;
Default handler: &textrsquo;
        s default footnote mechanism in many ways, including allow these two, as in this example.
      </para>
      <example endspaces=" ">
        <pre xml:space="preserve">
          \usepackage
Default handler: &lbrace;
          bigfoot
Default handler: &rbrace;
           % in preamble \DeclareNewFootnote
Default handler: &lbrace;
          Default
Default handler: &rbrace;
           \DeclareNewFootnote
Default handler: &lbrace;
          from
Default handler: &rbrace;
          [alph] % create class \footnotefrom
Default handler: &lbrace;
Default handler: &rbrace;
           ... The third theorem is a partial converse of the second.\footnotefrom
Default handler: &lbrace;
          % Noted in Wilson.\footnote
Default handler: &lbrace;
          Second edition only.
Default handler: &rbrace;
Default handler: &rbrace;
        </pre>
      </example>
    </section>
  </chapter>
  <node name="Definitions" spaces=" ">
    <nodename>
      Definitions
    </nodename>
    <nodenext automatic="on">
      Counters
    </nodenext>
    <nodeprev automatic="on">
      Footnotes
    </nodeprev>
    <nodeup automatic="on">
      Top
    </nodeup>
  </node>
  <chapter spaces=" ">
    <sectiontitle>
      Definitions
    </sectiontitle>
    <cindex index="cp" spaces=" ">
      <indexterm index="cp" number="501">
        definitions
      </indexterm>
    </cindex>
    <paraDefault handler: &latex;
>
       has support for making new commands of many different kinds.
    </para>
    <menu endspaces=" ">
      <menuentry>
        <menuleadingtext>
          *
        </menuleadingtext>
        <menunode>
          \newcommand
          &
           \renewcommand
        </menunode>
        <menuseparator>
          ::
        </menuseparator>
        <menudescription>
          <pre xml:space="preserve">
            (Re)define a new command.
          </pre>
        </menudescription>
      </menuentry>
      <menuentry>
        <menuleadingtext>
          *
        </menuleadingtext>
        <menunode>
          \providecommand
        </menunode>
        <menuseparator>
          ::
        </menuseparator>
        <menudescription>
          <pre xml:space="preserve">
            Define a new command, if name not used.
          </pre>
        </menudescription>
      </menuentry>
      <menuentry>
        <menuleadingtext>
          *
        </menuleadingtext>
        <menunode>
          \makeatletter
          &
           \makeatother
        </menunode>
        <menuseparator>
          ::
        </menuseparator>
        <menudescription>
          <pre xml:space="preserve">
            Change the status of the at-sign character.
          </pre>
        </menudescription>
      </menuentry>
      <menuentry>
        <menuleadingtext>
          *
        </menuleadingtext>
        <menunode>
          \
Default handler: &arobase;
          ifstar
        </menunode>
        <menuseparator>
          ::
        </menuseparator>
        <menudescription>
          <pre xml:space="preserve">
            Define your own commands with *-variants.
          </pre>
        </menudescription>
      </menuentry>
      <menuentry>
        <menuleadingtext>
          *
        </menuleadingtext>
        <menunode>
          \newcounter
        </menunode>
        <menuseparator>
          ::
        </menuseparator>
        <menudescription>
          <pre xml:space="preserve">
            Define a new counter.
          </pre>
        </menudescription>
      </menuentry>
      <menuentry>
        <menuleadingtext>
          *
        </menuleadingtext>
        <menunode>
          \newlength
        </menunode>
        <menuseparator>
          ::
        </menuseparator>
        <menudescription>
          <pre xml:space="preserve">
            Define a new length.
          </pre>
        </menudescription>
      </menuentry>
      <menuentry>
        <menuleadingtext>
          *
        </menuleadingtext>
        <menunode>
          \newsavebox
        </menunode>
        <menuseparator>
          ::
        </menuseparator>
        <menudescription>
          <pre xml:space="preserve">
            Define a new box.
          </pre>
        </menudescription>
      </menuentry>
      <menuentry>
        <menuleadingtext>
          *
        </menuleadingtext>
        <menunode>
          \newenvironment
          &
           \renewenvironment
        </menunode>
        <menuseparator>
          ::
        </menuseparator>
        <menudescription>
          <pre xml:space="preserve">
            Define a new environment.
          </pre>
        </menudescription>
      </menuentry>
      <menuentry>
        <menuleadingtext>
          *
        </menuleadingtext>
        <menunode>
          \newtheorem
        </menunode>
        <menuseparator>
          ::
        </menuseparator>
        <menudescription>
          <pre xml:space="preserve">
            Define a new theorem-like environment.
          </pre>
        </menudescription>
      </menuentry>
      <menuentry>
        <menuleadingtext>
          *
        </menuleadingtext>
        <menunode>
          \newfont
        </menunode>
        <menuseparator>
          ::
        </menuseparator>
        <menudescription>
          <pre xml:space="preserve">
            Define a new font name.
          </pre>
        </menudescription>
      </menuentry>
      <menuentry>
        <menuleadingtext>
          *
        </menuleadingtext>
        <menunode>
          \protect
        </menunode>
        <menuseparator>
          ::
        </menuseparator>
        <menudescription>
          <pre xml:space="preserve">
            Using tricky commands.
          </pre>
        </menudescription>
      </menuentry>
      <menuentry>
        <menuleadingtext>
          *
        </menuleadingtext>
        <menunode>
          \ignorespaces
          &
           \ignorespacesafterend
        </menunode>
        <menuseparator>
          ::
        </menuseparator>
        <menudescription>
          <pre xml:space="preserve">
            Discard extra spaces.
          </pre>
        </menudescription>
      </menuentry>
      <menuentry>
        <menuleadingtext>
          *
        </menuleadingtext>
        <menunode>
          xspace package
        </menunode>
        <menuseparator>
          ::
        </menuseparator>
        <menudescription>
          <pre xml:space="preserve">
            Space after a macro, conditionally.
          </pre>
        </menudescription>
      </menuentry>
      <menuentry>
        <menuleadingtext>
          *
        </menuleadingtext>
        <menunode>
          Class and package commands
        </menunode>
        <menuseparator>
          ::
        </menuseparator>
        <menudescription>
          <pre xml:space="preserve">
            Primarily for LaTeX programmers.
          </pre>
        </menudescription>
      </menuentry>
    </menu>
    <node name="_005cnewcommand-_0026-_005crenewcommand" spaces=" ">
      <nodename>
        \newcommand
        &
         \renewcommand
      </nodename>
      <nodenext automatic="on">
        \providecommand
      </nodenext>
      <nodeup automatic="on">
        Definitions
      </nodeup>
    </node>
    <section spaces=" ">
      <sectiontitle>
        <code>
          \newcommand
        </code>
        &
        <code>
          \renewcommand
        </code>
      </sectiontitle>
      <anchor name="_005cnewcommand">
        \newcommand
      </anchor>
      <anchor name="_005crenewcommand">
        \renewcommand
      </anchor>
      <findex index="fn" spaces=" ">
        <indexterm index="fn" number="489" mergedindex="cp">
          \newcommand
        </indexterm>
      </findex>
      <findex index="fn" spaces=" ">
        <indexterm index="fn" number="490" mergedindex="cp">
          \renewcommand
        </indexterm>
      </findex>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="502">
          commands, defining new ones
        </indexterm>
      </cindex>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="503">
          commands, redefining
        </indexterm>
      </cindex>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="504">
          defining a new command
        </indexterm>
      </cindex>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="505">
          redefining a command
        </indexterm>
      </cindex>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="506">
          new commands, defining
        </indexterm>
      </cindex>
      <para>
        Synopses, one of (three regular forms, three starred forms):
      </para>
      <example endspaces=" ">
        <pre xml:space="preserve">
          \newcommand
Default handler: &lbrace;
          \
          <var>
            cmd
          </var>
Default handler: &rbrace;
Default handler: &lbrace;
          <var>
            defn
          </var>
Default handler: &rbrace;
           \newcommand
Default handler: &lbrace;
          \
          <var>
            cmd
          </var>
Default handler: &rbrace;
          [
          <var>
            nargs
          </var>
          ]
Default handler: &lbrace;
          <var>
            defn
          </var>
Default handler: &rbrace;
           \newcommand
Default handler: &lbrace;
          \
          <var>
            cmd
          </var>
Default handler: &rbrace;
          [
          <var>
            nargs
          </var>
          ][
          <var>
            optargdefault
          </var>
          ]
Default handler: &lbrace;
          <var>
            defn
          </var>
Default handler: &rbrace;
           \newcommand*
Default handler: &lbrace;
          \
          <var>
            cmd
          </var>
Default handler: &rbrace;
Default handler: &lbrace;
          <var>
            defn
          </var>
Default handler: &rbrace;
           \newcommand*
Default handler: &lbrace;
          \
          <var>
            cmd
          </var>
Default handler: &rbrace;
          [
          <var>
            nargs
          </var>
          ]
Default handler: &lbrace;
          <var>
            defn
          </var>
Default handler: &rbrace;
           \newcommand*
Default handler: &lbrace;
          \
          <var>
            cmd
          </var>
Default handler: &rbrace;
          [
          <var>
            nargs
          </var>
          ][
          <var>
            optargdefault
          </var>
          ]
Default handler: &lbrace;
          <var>
            defn
          </var>
Default handler: &rbrace;
        </pre>
      </example>
      <noindent/>
      <para>
        or the same six possibilities with
        <code>
          \renewcommand
        </code>
         instead of
        <code>
          \newcommand
        </code>
        :
      </para>
      <example endspaces=" ">
        <pre xml:space="preserve">
          \renewcommand
Default handler: &lbrace;
          \
          <var>
            cmd
          </var>
Default handler: &rbrace;
Default handler: &lbrace;
          <var>
            defn
          </var>
Default handler: &rbrace;
           \renewcommand
Default handler: &lbrace;
          \
          <var>
            cmd
          </var>
Default handler: &rbrace;
          [
          <var>
            nargs
          </var>
          ]
Default handler: &lbrace;
          <var>
            defn
          </var>
Default handler: &rbrace;
           \renewcommand
Default handler: &lbrace;
          \
          <var>
            cmd
          </var>
Default handler: &rbrace;
          [
          <var>
            nargs
          </var>
          ][
          <var>
            optargdefault
          </var>
          ]
Default handler: &lbrace;
          <var>
            defn
          </var>
Default handler: &rbrace;
           \renewcommand*
Default handler: &lbrace;
          \
          <var>
            cmd
          </var>
Default handler: &rbrace;
Default handler: &lbrace;
          <var>
            defn
          </var>
Default handler: &rbrace;
           \renewcommand*
Default handler: &lbrace;
          \
          <var>
            cmd
          </var>
Default handler: &rbrace;
          [
          <var>
            nargs
          </var>
          ]
Default handler: &lbrace;
          <var>
            defn
          </var>
Default handler: &rbrace;
           \renewcommand*
Default handler: &lbrace;
          \
          <var>
            cmd
          </var>
Default handler: &rbrace;
          [
          <var>
            nargs
          </var>
          ][
          <var>
            optargdefault
          </var>
          ]
Default handler: &lbrace;
          <var>
            defn
          </var>
Default handler: &rbrace;
        </pre>
      </example>
      <para>
        Define or redefine a command (see also
        <code>
          \DeclareRobustCommand
        </code>
         in
        <ref label="Class-and-package-commands">
          <xrefnodename>
            Class and package commands
          </xrefnodename>
        </ref>
        ).
      </para>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="507">
          starred form, defining new commands
        </indexterm>
      </cindex>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="508">
          *-form, defining new commands
        </indexterm>
      </cindex>
      <findex index="fn" spaces=" ">
        <indexterm index="fn" number="491" mergedindex="cp">
          \long
          <r>
            , not defining a command as
          </r>
        </indexterm>
      </findex>
      <para>
        The starred form of these two forbids the arguments from containing multiple paragraphs of text (i.e., a
        <code>
          \par
        </code>
         token; in plain
Default handler: &tex;
         terms: the commands are not
        <code>
          \long
        </code>
        ). With the default form, arguments can be multiple paragraphs.
      </para>
      <para>
        These are the parameters (examples follow):
      </para>
      <table commandarg="var" spaces=" " endspaces=" ">
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="var">
                cmd
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <para>
              Required;
              <code>
                \
                <var>
                  cmd
                </var>
              </code>
               is the command name. It must begin with a backslash,
              <code>
                \
              </code>
              , and must not begin with the four character string
              <code>
                \end
              </code>
              . For
              <code>
                \newcommand
              </code>
              , it must not be already defined. For
              <code>
                \renewcommand
              </code>
              , this name must already be defined.
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="var">
                nargs
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <para>
              Optional; an integer from 0 to 9, specifying the number of arguments that the command takes, including any optional argument. Omitting this argument is the same as specifying 0, meaning that the command has no arguments. If you redefine a command, the new version can have a different number of arguments than the old version.
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="var">
                optargdefault
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <cindex index="cp" spaces=" ">
              <indexterm index="cp" number="509">
                optional arguments, defining and using
              </indexterm>
            </cindex>
            <cindex index="cp" spaces=" ">
              <indexterm index="cp" number="510">
                arguments, optional, defining and using
              </indexterm>
            </cindex>
            <para>
              Optional; if this argument is present then the first argument of
              <code>
                \
                <var>
                  cmd
                </var>
              </code>
               is optional, with default value
              <var>
                optargdefault
              </var>
               (which may be the empty string). If
              <var>
                optargdefault
              </var>
               is not present then
              <code>
                \
                <var>
                  cmd
                </var>
              </code>
               does not take an optional argument.
            </para>
            <para>
              That is, if
              <code>
                \
                <var>
                  cmd
                </var>
              </code>
               is called with a following argument in square brackets, as in
              <code>
                \
                <var>
                  cmd
                </var>
                [
                <var>
                  optval
                </var>
                ]
Default handler: &lbrace;
                ...
Default handler: &rbrace;
                ...
              </code>
              , then within
              <var>
                defn
              </var>
               the parameter
Default handler: &nbsp;
              <code>
                #1
              </code>
               is set to
              <var>
                optval
              </var>
              . On the other hand, if
              <code>
                \
                <var>
                  cmd
                </var>
              </code>
               is called without following square brackets then within
              <var>
                defn
              </var>
               the parameter
              <code>
                #1
              </code>
               is set to
              <var>
                optargdefault
              </var>
              . In either case, the required arguments start with
              <code>
                #2
              </code>
              .
            </para>
            <para>
              Omitting
              <code>
                [
                <var>
                  optargdefault
                </var>
                ]
              </code>
               from the definition is entirely different from giving the square brackets with empty contents, as in
              <code>
                []
              </code>
              . The former says the command being defined takes no optional argument, so
              <code>
                #1
              </code>
               is the first required argument (if
              <math>
                <var>
                  nargs
                </var>
Default handler: &ge;
                 1
              </math>
              ); the latter sets the optional argument
              <code>
                #1
              </code>
               to the empty string as the default, if no optional argument was given in the call.
            </para>
            <para>
              Similarly, omitting
              <code>
                [
                <var>
                  optval
                </var>
                ]
              </code>
               from a call is also entirely different from giving the square brackets with empty contents. The former sets
              <code>
                #1
              </code>
               to the value of
              <var>
                optval
              </var>
               (assuming the command was defined to take an optional argument); the latter sets
              <code>
                #1
              </code>
               to the empty string, just as with any other value.
            </para>
            <para>
              If a command is not defined to take an optional argument, but is called with an optional argument, the results are unpredictable: there may be a
Default handler: &latex;
               error, there may be incorrect typeset output, or both.
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="var">
                defn
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <cindex index="cp" spaces=" ">
              <indexterm index="cp" number="511">
                parameters, substituting
              </indexterm>
            </cindex>
            <para>
              Required; the text to be substituted for every occurrence of
              <code>
                \
                <var>
                  cmd
                </var>
              </code>
              . The parameters
              <code>
                #1
              </code>
              ,
              <code>
                #2
              </code>
              ,
Default handler: &dots;
              ,
              <code>
                #
                <var>
                  nargs
                </var>
              </code>
               are replaced by the values supplied when the command is called (or by
              <var>
                optargdefault
              </var>
               in the case of an optional argument not specified in the call, as just explained).
            </para>
          </tableitem>
        </tableentry>
      </table>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="512">
          blanks, after control sequences
        </indexterm>
      </cindex>
      <paraDefault handler: &tex;
>
         ignores blanks in the source following a control word (
        <pxref label="Control-sequences">
          <xrefnodename>
            Control sequences
          </xrefnodename>
        </pxref>
        ), as in
        <samp>
          \cmd
        </samp>
        . If you want a space there, one solution is to type
        <codeDefault handler: &lbrace;
Default handler: &rbrace;
/>
         after the command (
        <samp>
          \cmd
Default handler: &lbrace;
Default handler: &rbrace;
        </samp>
        ), and another solution is to use an explicit control space (
        <samp>
          \cmd\
        </samp>
        ).
      </para>
      <para>
        A simple example of defining a new command:
        <code>
          \newcommand
Default handler: &lbrace;
          \RS
Default handler: &rbrace;
Default handler: &lbrace;
          Robin Smith
Default handler: &rbrace;
        </code>
         results in
        <code>
          \RS
        </code>
         being replaced by the longer text. Redefining an existing command is similar:
        <code>
          \renewcommand
Default handler: &lbrace;
          \qedsymbol
Default handler: &rbrace;
Default handler: &lbrace;
Default handler: &lbrace;
          \small QED
Default handler: &rbrace;
Default handler: &rbrace;
        </code>
        .
      </para>
      <para>
        If you use
        <code>
          \newcommand
        </code>
         and the command name has already been used then you get something like
        <samp>
          LaTeX Error: Command \fred already defined. Or name \end... illegal, see p.192 of the manual
        </samp>
        . Similarly, If you use
        <code>
          \renewcommand
        </code>
         and the command name has not been defined then you get something like
        <samp>
          LaTeX Error: \hank undefined
        </samp>
        .
      </para>
      <para>
        Here the first definition creates a command with no arguments, and the second, a command with one required argument:
      </para>
      <example endspaces=" ">
        <pre xml:space="preserve">
          \newcommand
Default handler: &lbrace;
          \student
Default handler: &rbrace;
Default handler: &lbrace;
          Ms~O'Leary
Default handler: &rbrace;
           \newcommand
Default handler: &lbrace;
          \defref
Default handler: &rbrace;
          [1]
Default handler: &lbrace;
          Definition~\ref
Default handler: &lbrace;
          #1
Default handler: &rbrace;
Default handler: &rbrace;
        </pre>
      </example>
      <noindent/>
      <para>
        Use the first as in
        <code>
          I highly recommend \student
Default handler: &lbrace;
Default handler: &rbrace;
           to you
        </code>
        . The second has a variable argument, so that
        <code>
          \defref
Default handler: &lbrace;
          def:basis
Default handler: &rbrace;
        </code>
         expands to
        <code>
          Definition~\ref
Default handler: &lbrace;
          def:basis
Default handler: &rbrace;
        </code>
        , which ultimately expands to something like
        <samp>
          Definition~3.14
        </samp>
        .
      </para>
      <para>
        Similarly, but with two required arguments:
        <code>
          \newcommand
Default handler: &lbrace;
          \nbym
Default handler: &rbrace;
          [2]
Default handler: &lbrace;
          $#1 \times #2$
Default handler: &rbrace;
        </code>
         is invoked as
        <code>
          \nbym
Default handler: &lbrace;
          2
Default handler: &rbrace;
Default handler: &lbrace;
          k
Default handler: &rbrace;
        </code>
        .
      </para>
      <para>
        This example has an optional argument.
      </para>
      <example endspaces=" ">
        <pre xml:space="preserve">
          \newcommand
Default handler: &lbrace;
          \salutation
Default handler: &rbrace;
          [1][Sir or Madam]
Default handler: &lbrace;
          Dear #1:
Default handler: &rbrace;
        </pre>
      </example>
      <noindent/>
      <para>
        Then
        <code>
          \salutation
        </code>
         gives
        <samp>
          Dear Sir or Madam:
        </samp>
         while
        <code>
          \salutation[John]
        </code>
         gives
        <samp>
          Dear John:
        </samp>
        . And
        <code>
          \salutation[]
        </code>
         gives
        <samp>
          Dear :
        </samp>
        .
      </para>
      <para>
        This example has an optional argument and two required arguments.
      </para>
      <example endspaces=" ">
        <pre xml:space="preserve">
          \newcommand
Default handler: &lbrace;
          \lawyers
Default handler: &rbrace;
          [3][company]
Default handler: &lbrace;
          #2, #3, and~#1
Default handler: &rbrace;
           I employ \lawyers[Howe]
Default handler: &lbrace;
          Dewey
Default handler: &rbrace;
Default handler: &lbrace;
          Cheatem
Default handler: &rbrace;
          .
        </pre>
      </example>
      <noindent/>
      <para>
        The output is
        <samp>
          I employ Dewey, Cheatem, and Howe.
        </samp>
        . The optional argument,
        <code>
          Howe
        </code>
        , is associated with
        <code>
          #1
        </code>
        , while
        <code>
          Dewey
        </code>
         and
        <code>
          Cheatem
        </code>
         are associated with
        <code>
          #2
        </code>
         and
Default handler: &nbsp;
        <code>
          #3
        </code>
        . Because of the optional argument,
        <code>
          \lawyers
Default handler: &lbrace;
          Dewey
Default handler: &rbrace;
Default handler: &lbrace;
          Cheatem
Default handler: &rbrace;
        </code>
         will give the output
        <samp>
          I employ Dewey, Cheatem, and company.
        </samp>
        .
      </para>
      <para>
        The braces around
        <var>
          defn
        </var>
         do not define a group, that is, they do not delimit the scope of the result of expanding
        <var>
          defn
        </var>
        . For example, with
        <code>
          \newcommand
Default handler: &lbrace;
          \shipname
Default handler: &rbrace;
          [1]
Default handler: &lbrace;
          \it #1
Default handler: &rbrace;
        </code>
        , in this sentence,
      </para>
      <example endspaces=" ">
        <pre xml:space="preserve">
          The \shipname
Default handler: &lbrace;
          Monitor
Default handler: &rbrace;
           met the \shipname
Default handler: &lbrace;
          Merrimac
Default handler: &rbrace;
          .
        </pre>
      </example>
      <noindent/>
      <para>
        the words
        <samp>
          met the
        </samp>
        , and the period, would incorrectly be in italics. The solution is to put another pair of braces inside the definition:
        <code>
          \newcommand
Default handler: &lbrace;
          \shipname
Default handler: &rbrace;
          [1]
Default handler: &lbrace;
Default handler: &lbrace;
          \it #1
Default handler: &rbrace;
Default handler: &rbrace;
        </code>
        .
      </para>
      <menu endspaces=" ">
        <menuentry>
          <menuleadingtext>
            *
          </menuleadingtext>
          <menunode>
            Control sequences
          </menunode>
          <menuseparator>
            ::
          </menuseparator>
          <menudescription>
            <pre xml:space="preserve">
              Control sequence, control word and control symbol.
            </pre>
          </menudescription>
        </menuentry>
      </menu>
      <node name="Control-sequences" spaces=" ">
        <nodename>
          Control sequences
        </nodename>
        <nodeup automatic="on">
          \newcommand
          &
           \renewcommand
        </nodeup>
      </node>
      <subsection spaces=" ">
        <sectiontitle>
          Control sequence, control word and control symbol
        </sectiontitle>
        <cindex index="cp" spaces=" ">
          <indexterm index="cp" number="513">
            control sequences
          </indexterm>
        </cindex>
        <para>
          When reading input
Default handler: &tex;
           converts the stream of read characters into a sequence of
          <dfn>
            tokens
          </dfn>
          . When
Default handler: &tex;
           sees a backslash
          <code>
            \
          </code>
          , it will handle the following characters in a special way in order to make a
          <dfn>
            control sequence
          </dfn>
           token.
        </para>
        <para>
          The control sequences fall into two categories:
        </para>
        <itemize commandarg="bullet" automaticcommandarg="on" endspaces=" ">
          <itemprepend>
            <formattingcommand command="bullet" automatic="on"/>
          </itemprepend>
          <listitem>
            <prependDefault handler: &bullet;
/>
            <cindex index="cp" spaces=" ">
              <indexterm index="cp" number="514">
                control word, defined
              </indexterm>
            </cindex>
            <para>
              <dfn>
                control word
              </dfn>
              , when the control sequence is gathered from a
              <code>
                \
              </code>
               followed by at least one ASCII letter (
              <code>
                A-Z
              </code>
               and
              <code>
                a-z
              </code>
              ), followed by at least one non-letter.
            </para>
          </listitem>
          <listitem>
            <prependDefault handler: &bullet;
/>
            <cindex index="cp" spaces=" ">
              <indexterm index="cp" number="515">
                control symbol, defined
              </indexterm>
            </cindex>
            <para>
              <dfn>
                control symbol
              </dfn>
              , when the control sequence is gathered from a
              <code>
                \
              </code>
               followed by one non-letter character.
            </para>
          </listitem>
        </itemize>
        <para>
          The sequence of characters so found after the
          <code>
            \
          </code>
           is also called the
          <dfn>
            control sequence name
          </dfn>
          .
        </para>
        <para>
          Blanks after a control word are ignored and do not produce any whitespace in the output (
          <pxref label="_005cnewcommand-_0026-_005crenewcommand">
            <xrefnodename>
              \newcommand
              &
               \renewcommand
            </xrefnodename>
          </pxref>
           and
          <ref label="_005c_0028SPACE_0029">
            <xrefnodename>
              \(SPACE)
            </xrefnodename>
          </ref>
          ).
        </para>
        <para>
          Just as the
          <code>
            \relax
          </code>
           command does nothing, the following input will simply print
          <samp>
            Hello!
          </samp>
          <inlinefmt>
            <inlinefmtformat>
              tex
            </inlinefmtformat>
            <inlinefmtcontent>
              We use visible spaces @samp{@visiblespace{}} instead of blanks
            </inlinefmtcontent>
          </inlinefmt>
          <inlinefmt>
            <inlinefmtformat>
              info
            </inlinefmtformat>
            <inlinefmtcontent>
               (if you use the Emacs info viewer@comma{} turn on the @code{whitespace-mode} minor mode to see the trailing spaces)
            </inlinefmtcontent>
          </inlinefmt>
          :
        </para>
        <example endspaces=" ">
          <pre xml:space="preserve">
            Hel\relax
            <w/>
            <w/>
            <w/>
            <w/>
            <w/>
            <w/>
            lo!
          </pre>
        </example>
        <noindent/>
        <para>
          This is because blanks after
          <code>
            \relax
          </code>
          , including the newline, are ignored, and blanks at the beginning of a line are also ignored (
          <pxref label="Leading-blanks">
            <xrefnodename>
              Leading blanks
            </xrefnodename>
          </pxref>
          ).
        </para>
      </subsection>
    </section>
    <node name="_005cprovidecommand" spaces=" ">
      <nodename trailingspaces=" ">
        \providecommand
      </nodename>
      <nodenext automatic="on">
        \makeatletter
        &
         \makeatother
      </nodenext>
      <nodeprev automatic="on">
        \newcommand
        &
         \renewcommand
      </nodeprev>
      <nodeup automatic="on">
        Definitions
      </nodeup>
    </node>
    <section spaces=" ">
      <sectiontitle>
        <code>
          \providecommand
        </code>
      </sectiontitle>
      <findex index="fn" spaces=" ">
        <indexterm index="fn" number="492" mergedindex="cp">
          \providecommand
        </indexterm>
      </findex>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="516">
          commands, defining new ones
        </indexterm>
      </cindex>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="517">
          defining a new command
        </indexterm>
      </cindex>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="518">
          new commands, defining
        </indexterm>
      </cindex>
      <para>
        Synopses, one of:
      </para>
      <example endspaces=" ">
        <pre xml:space="preserve">
          \providecommand
Default handler: &lbrace;
          \
          <var>
            cmd
          </var>
Default handler: &rbrace;
Default handler: &lbrace;
          <var>
            defn
          </var>
Default handler: &rbrace;
           \providecommand
Default handler: &lbrace;
          \
          <var>
            cmd
          </var>
Default handler: &rbrace;
          [
          <var>
            nargs
          </var>
          ]
Default handler: &lbrace;
          <var>
            defn
          </var>
Default handler: &rbrace;
           \providecommand
Default handler: &lbrace;
          \
          <var>
            cmd
          </var>
Default handler: &rbrace;
          [
          <var>
            nargs
          </var>
          ][
          <var>
            optargdefault
          </var>
          ]
Default handler: &lbrace;
          <var>
            defn
          </var>
Default handler: &rbrace;
           \providecommand*
Default handler: &lbrace;
          \
          <var>
            cmd
          </var>
Default handler: &rbrace;
Default handler: &lbrace;
          <var>
            defn
          </var>
Default handler: &rbrace;
           \providecommand*
Default handler: &lbrace;
          \
          <var>
            cmd
          </var>
Default handler: &rbrace;
          [
          <var>
            nargs
          </var>
          ]
Default handler: &lbrace;
          <var>
            defn
          </var>
Default handler: &rbrace;
           \providecommand*
Default handler: &lbrace;
          \
          <var>
            cmd
          </var>
Default handler: &rbrace;
          [
          <var>
            nargs
          </var>
          ][
          <var>
            optargdefault
          </var>
          ]
Default handler: &lbrace;
          <var>
            defn
          </var>
Default handler: &rbrace;
        </pre>
      </example>
      <para>
        Defines a command, as long as no command of this name already exists. If no command of this name already exists then this has the same effect as
        <code>
          \newcommand
        </code>
        . If a command of this name already exists then this definition does nothing. This is particularly useful in a file that may be loaded more than once, such as a style file.
        <xref label="_005cnewcommand-_0026-_005crenewcommand">
          <xrefnodename>
            \newcommand
            &
             \renewcommand
          </xrefnodename>
        </xref>
        , for the description of the arguments.
      </para>
      <para>
        This example
      </para>
      <example endspaces=" ">
        <pre xml:space="preserve">
          \providecommand
Default handler: &lbrace;
          \myaffiliation
Default handler: &rbrace;
Default handler: &lbrace;
          Saint Michael's College
Default handler: &rbrace;
           \providecommand
Default handler: &lbrace;
          \myaffiliation
Default handler: &rbrace;
Default handler: &lbrace;
          Lyc\'ee Henri IV
Default handler: &rbrace;
           From \myaffiliation.
        </pre>
      </example>
      <noindent/>
      <para>
        outputs
        <samp>
          From Saint Michael's College.
        </samp>
        . Unlike
        <code>
          \newcommand
        </code>
        , the repeated use of
        <code>
          \providecommand
        </code>
         to (try to) define
        <code>
          \myaffiliation
        </code>
         does not give an error.
      </para>
    </section>
    <node name="_005cmakeatletter-_0026-_005cmakeatother" spaces=" ">
      <nodename>
        \makeatletter
        &
         \makeatother
      </nodename>
      <nodenext automatic="on">
        \
Default handler: &arobase;
        ifstar
      </nodenext>
      <nodeprev automatic="on">
        \providecommand
      </nodeprev>
      <nodeup automatic="on">
        Definitions
      </nodeup>
    </node>
    <section spaces=" ">
      <sectiontitle>
        <code>
          \makeatletter
        </code>
        &
        <code>
          \makeatother
        </code>
      </sectiontitle>
      <anchor name="_005cmakeatletter">
        \makeatletter
      </anchor>
      <anchor name="_005cmakeatother">
        \makeatother
      </anchor>
      <findex index="fn" spaces=" ">
        <indexterm index="fn" number="493" mergedindex="cp">
          \makeatother
        </indexterm>
      </findex>
      <findex index="fn" spaces=" ">
        <indexterm index="fn" number="494" mergedindex="cp">
          \makeatother
        </indexterm>
      </findex>
      <para>
        Synopsis:
      </para>
      <example endspaces=" ">
        <pre xml:space="preserve">
          \makeatletter ... definition of commands with
Default handler: &arobase;
           in their name .. \makeatother
        </pre>
      </example>
      <para>
        Use this pair when you redefine
Default handler: &latex;
         commands that are named with an at-sign character
Default handler: &nbsp;
        <samp>
          <codeDefault handler: &arobase;
/>
        </samp>
        . The
        <code>
          \makeatletter
        </code>
         declaration makes the at-sign character have the category code of a letter, code
Default handler: &nbsp;
        11. The
        <code>
          \makeatother
        </code>
         declaration sets the category code of the at-sign to code
Default handler: &nbsp;
        12, its default value.
      </para>
      <para>
        As
Default handler: &tex;
         reads characters, it assigns each one a category code, or
        <cindex index="cp" spaces=" ">
          <indexterm index="cp" number="519">
            catcode
          </indexterm>
        </cindex>
        <cindex index="cp" spaces=" ">
          <indexterm index="cp" number="520">
            character category code
          </indexterm>
        </cindex>
        <cindex index="cp" spaces=" ">
          <indexterm index="cp" number="521">
            category code, character
          </indexterm>
        </cindex>
        <dfn>
          catcode
        </dfn>
        . For instance, it assigns the backslash character
Default handler: &nbsp;
        <samp>
          <code>
            \
          </code>
        </samp>
         the catcode
Default handler: &nbsp;
        0. Command names consist of a category
Default handler: &nbsp;
        0 character, ordinarily backslash, followed by letters, category
Default handler: &nbsp;
        11 characters (except that a command name can also consist of a category
Default handler: &nbsp;
        0 character followed by a single non-letter symbol).
      </para>
      <paraDefault handler: &latex;
Default handler: &textrsquo;
>
        s source code has the convention that some commands use
        <codeDefault handler: &arobase;
/>
         in their name. These commands are mainly intended for package or class writers. The convention prevents authors who are just using a package or class from accidentally replacing such a command with one of their own, because by default the at-sign has catcode
Default handler: &nbsp;
        12.
      </para>
      <para>
        Use the pair
        <code>
          \makeatletter
        </code>
         and
        <code>
          \makeatother
        </code>
         inside a
        <file>
          .tex
        </file>
         file, typically in the preamble, when you are defining or redefining commands named with
        <codeDefault handler: &arobase;
/>
        , by having them surround your definition. Don
Default handler: &textrsquo;
        t use these inside
        <file>
          .sty
        </file>
         or
        <file>
          .cls
        </file>
         files since the
        <code>
          \usepackage
        </code>
         and
        <code>
          \documentclass
        </code>
         commands already arrange that the at-sign has the character code of a letter, catcode
Default handler: &nbsp;
        11.
      </para>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="522">
          <r>
            package
          </r>
          ,
          <code>
            macros2e
          </code>
        </indexterm>
      </cindex>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="523">
          <code>
            macros2e
          </code>
          <r>
            package
          </r>
        </indexterm>
      </cindex>
      <para>
        For a comprehensive list of macros with an at-sign in their names see
        <url>
          <urefurl>
            https://ctan.org/pkg/macros2e
          </urefurl>
        </url>
        .
      </para>
      <para>
        In this example the class file has a command
        <code>
          \thesis
Default handler: &arobase;
          universityname
        </code>
         that the user wants to change. These three lines should go in the preamble, before the
        <code>
          \begin
Default handler: &lbrace;
          document
Default handler: &rbrace;
        </code>
        .
      </para>
      <example endspaces=" ">
        <pre xml:space="preserve">
          \makeatletter \renewcommand
Default handler: &lbrace;
          \thesis
Default handler: &arobase;
          universityname
Default handler: &rbrace;
Default handler: &lbrace;
          Saint Michael's College
Default handler: &rbrace;
           \makeatother
        </pre>
      </example>
    </section>
    <node name="_005c_0040ifstar" spaces=" ">
      <nodename>
        \
Default handler: &arobase;
        ifstar
      </nodename>
      <nodenext automatic="on">
        \newcounter
      </nodenext>
      <nodeprev automatic="on">
        \makeatletter
        &
         \makeatother
      </nodeprev>
      <nodeup automatic="on">
        Definitions
      </nodeup>
    </node>
    <section spaces=" ">
      <sectiontitle>
        <code>
          \
Default handler: &arobase;
          ifstar
        </code>
      </sectiontitle>
      <findex index="fn" spaces=" ">
        <indexterm index="fn" number="495" mergedindex="cp">
          \
Default handler: &arobase;
          ifstar
        </indexterm>
      </findex>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="524">
          commands, star-variants
        </indexterm>
      </cindex>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="525">
          star-variants, commands
        </indexterm>
      </cindex>
      <para>
        Synopsis:
      </para>
      <example endspaces=" ">
        <pre xml:space="preserve">
          \newcommand
Default handler: &lbrace;
          \mycmd
Default handler: &rbrace;
Default handler: &lbrace;
          \
Default handler: &arobase;
          ifstar
Default handler: &lbrace;
          \mycmd
Default handler: &arobase;
          star
Default handler: &rbrace;
Default handler: &lbrace;
          \mycmd
Default handler: &arobase;
          nostar
Default handler: &rbrace;
Default handler: &rbrace;
           \newcommand
Default handler: &lbrace;
          \mycmd
Default handler: &arobase;
          nostar
Default handler: &rbrace;
          [
          <var>
            nostar-num-args
          </var>
          ]
Default handler: &lbrace;
          <var>
            nostar-body
          </var>
Default handler: &rbrace;
           \newcommand
Default handler: &lbrace;
          \mycmd
Default handler: &arobase;
          star
Default handler: &rbrace;
          [
          <var>
            star-num-args
          </var>
          ]
Default handler: &lbrace;
          <var>
            star-body
          </var>
Default handler: &rbrace;
        </pre>
      </example>
      <para>
        Many standard
Default handler: &latex;
         environments or commands have a variant with the same name but ending with a star character
Default handler: &nbsp;
        <code>
          *
        </code>
        , an asterisk. Examples are the
        <code>
          table
        </code>
         and
        <code>
          table*
        </code>
         environments and the
        <code>
          \section
        </code>
         and
        <code>
          \section*
        </code>
         commands.
      </para>
      <para>
        When defining environments, following this pattern is straightforward because
        <code>
          \newenvironment
        </code>
         and
        <code>
          \renewenvironment
        </code>
         allow the environment name to contain a star. So you just have to write
        <code>
          \newenvironment
Default handler: &lbrace;
          <var>
            myenv
          </var>
Default handler: &rbrace;
        </code>
         or
        <code>
          \newenvironment
Default handler: &lbrace;
          <var>
            myenv
          </var>
          *
Default handler: &rbrace;
        </code>
         and continue the definition as usual. For commands the situation is more complex as the star not being a letter cannot be part of the command name. As in the synopsis above, there will be a user-called command, given above as
        <code>
          \mycmd
        </code>
        , which peeks ahead to see if it is followed by a star. For instance,
Default handler: &latex;
         does not really have a
        <code>
          \section*
        </code>
         command; instead, the
        <code>
          \section
        </code>
         command peeks ahead. This command does not accept arguments but instead expands to one of two commands that do accept arguments. In the synopsis these two are
        <code>
          \mycmd
Default handler: &arobase;
          nostar
        </code>
         and
        <code>
          \mycmd
Default handler: &arobase;
          star
        </code>
        . They could take the same number of arguments or a different number, or no arguments at all. As always, in a
Default handler: &latex;
         document a command using an at-sign
Default handler: &nbsp;
        <codeDefault handler: &arobase;
/>
         in its name must be enclosed inside a
        <code>
          \makeatletter ... \makeatother
        </code>
         block (
        <pxref label="_005cmakeatletter-_0026-_005cmakeatother">
          <xrefnodename>
            \makeatletter
            &
             \makeatother
          </xrefnodename>
        </pxref>
        ).
      </para>
      <para>
        This example of
        <code>
          \
Default handler: &arobase;
          ifstar
        </code>
         defines the command
        <code>
          \ciel
        </code>
         and a variant
        <code>
          \ciel*
        </code>
        . Both have one required argument. A call to
        <code>
          \ciel
Default handler: &lbrace;
          blue
Default handler: &rbrace;
        </code>
         will return
        "
        not starry blue sky
        "
         while
        <code>
          \ciel*
Default handler: &lbrace;
          night
Default handler: &rbrace;
        </code>
         will return
        "
        starry night sky
        "
        .
      </para>
      <example endspaces=" ">
        <pre xml:space="preserve">
          \makeatletter \newcommand*
Default handler: &lbrace;
          \ciel
Default handler: &arobase;
          unstarred
Default handler: &rbrace;
          [1]
Default handler: &lbrace;
          not starry #1 sky
Default handler: &rbrace;
           \newcommand*
Default handler: &lbrace;
          \ciel
Default handler: &arobase;
          starred
Default handler: &rbrace;
          [1]
Default handler: &lbrace;
          starry #1 sky
Default handler: &rbrace;
           \newcommand*
Default handler: &lbrace;
          \ciel
Default handler: &rbrace;
Default handler: &lbrace;
          \
Default handler: &arobase;
          ifstar
Default handler: &lbrace;
          \ciel
Default handler: &arobase;
          starred
Default handler: &rbrace;
Default handler: &lbrace;
          \ciel
Default handler: &arobase;
          unstarred
Default handler: &rbrace;
Default handler: &rbrace;
           \makeatother
        </pre>
      </example>
      <para>
        In the next example, the starred variant takes a different number of arguments than the unstarred one. With this definition, Agent 007
Default handler: &textrsquo;
        s
        <code>
          ``My name is \agentsecret*
Default handler: &lbrace;
          Bond
Default handler: &rbrace;
          , \agentsecret
Default handler: &lbrace;
          James
Default handler: &rbrace;
Default handler: &lbrace;
          Bond
Default handler: &rbrace;
          .''
        </code>
         is equivalent to entering the commands
        <code>
          ``My name is \textsc
Default handler: &lbrace;
          Bond
Default handler: &rbrace;
          , \textit
Default handler: &lbrace;
          James
Default handler: &rbrace;
           textsc
Default handler: &lbrace;
          Bond
Default handler: &rbrace;
          .''
        </code>
      </para>
      <example endspaces=" ">
        <pre xml:space="preserve">
          \newcommand*
Default handler: &lbrace;
          \agentsecret
Default handler: &arobase;
          unstarred
Default handler: &rbrace;
          [2]
Default handler: &lbrace;
          \textit
Default handler: &lbrace;
          #1
Default handler: &rbrace;
           \textsc
Default handler: &lbrace;
          #2
Default handler: &rbrace;
Default handler: &rbrace;
           \newcommand*
Default handler: &lbrace;
          \agentsecret
Default handler: &arobase;
          starred
Default handler: &rbrace;
          [1]
Default handler: &lbrace;
          \textsc
Default handler: &lbrace;
          #1
Default handler: &rbrace;
Default handler: &rbrace;
           \newcommand*
Default handler: &lbrace;
          \agentsecret
Default handler: &rbrace;
Default handler: &lbrace;
          % \
Default handler: &arobase;
          ifstar
Default handler: &lbrace;
          \agentsecret
Default handler: &arobase;
          starred
Default handler: &rbrace;
Default handler: &lbrace;
          \agentsecret
Default handler: &arobase;
          unstarred
Default handler: &rbrace;
Default handler: &rbrace;
        </pre>
      </example>
      <para>
        After a command name, a star is handled similarly to an optional argument. (This differs from environment names in which the star is part of the name itself and as such could be in any position.) Thus, it is technically possible to put any number of spaces between the command and the star. Thus
        <code>
          \agentsecret*
Default handler: &lbrace;
          Bond
Default handler: &rbrace;
        </code>
         and
        <code>
          \agentsecret
          <w>
             *
          </w>
Default handler: &lbrace;
          Bond
Default handler: &rbrace;
        </code>
         are equivalent. However, the standard practice is not to insert any such spaces.
      </para>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="526">
          <r>
            package
          </r>
          ,
          <code>
            suffix
          </code>
        </indexterm>
      </cindex>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="527">
          <code>
            suffix
          </code>
          <r>
            package
          </r>
        </indexterm>
      </cindex>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="528">
          <r>
            package
          </r>
          ,
          <code>
            xparse
          </code>
        </indexterm>
      </cindex>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="529">
          <code>
            xparse
          </code>
          <r>
            package
          </r>
        </indexterm>
      </cindex>
      <para>
        There are two alternative ways to accomplish the work of
        <code>
          \
Default handler: &arobase;
          ifstar
        </code>
        . (1)
Default handler: &nbsp;
        The
        <code>
          suffix
        </code>
         package allows the construct
        <code>
          \newcommand\mycommand
Default handler: &lbrace;
          <var>
            unstarred-variant
          </var>
Default handler: &rbrace;
        </code>
         followed by
        <code>
          \WithSuffix\newcommand\mycommand*
Default handler: &lbrace;
          <var>
            starred-variant
          </var>
Default handler: &rbrace;
        </code>
        . (2)
Default handler: &nbsp;
Default handler: &latex;
         provides the
        <code>
          xparse
        </code>
         package, which allows this code:
      </para>
      <example endspaces=" ">
        <pre xml:space="preserve">
          \NewDocumentCommand\foo
Default handler: &lbrace;
          s
Default handler: &rbrace;
Default handler: &lbrace;
          \IfBooleanTF#1
Default handler: &lbrace;
          <var>
            starred-variant
          </var>
Default handler: &rbrace;
          %
Default handler: &lbrace;
          <var>
            unstarred-variant
          </var>
Default handler: &rbrace;
          %
Default handler: &rbrace;
        </pre>
      </example>
    </section>
    <node name="_005cnewcounter" spaces=" ">
      <nodename>
        \newcounter
      </nodename>
      <nodenext automatic="on">
        \newlength
      </nodenext>
      <nodeprev automatic="on">
        \
Default handler: &arobase;
        ifstar
      </nodeprev>
      <nodeup automatic="on">
        Definitions
      </nodeup>
    </node>
    <section spaces=" ">
      <sectiontitle>
        <code>
          \newcounter
        </code>
        : Allocating a counter
      </sectiontitle>
      <findex index="fn" spaces=" ">
        <indexterm index="fn" number="496" mergedindex="cp">
          \newcounter
        </indexterm>
      </findex>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="530">
          counters, defining new
        </indexterm>
      </cindex>
      <para>
        Synopsis, one of:
      </para>
      <example endspaces=" ">
        <pre xml:space="preserve">
          \newcounter
Default handler: &lbrace;
          <var>
            countername
          </var>
Default handler: &rbrace;
           \newcounter
Default handler: &lbrace;
          <var>
            countername
          </var>
Default handler: &rbrace;
          [
          <var>
            supercounter
          </var>
          ]
        </pre>
      </example>
      <para>
        Globally defines a new counter named
        <var>
          countername
        </var>
         and initialize it to zero (
        <pxref label="Counters">
          <xrefnodename>
            Counters
          </xrefnodename>
        </pxref>
        ).
      </para>
      <para>
        The name
        <var>
          countername
        </var>
         must consist of letters only. It does not begin with a backslash. This name must not already be in use by another counter.
      </para>
      <para>
        When you use the optional argument
        <code>
          [
          <var>
            supercounter
          </var>
          ]
        </code>
         then the counter
        <var>
          countername
        </var>
         will be reset to zero whenever
        <var>
          supercounter
        </var>
         is incremented. For example, ordinarily
        <code>
          subsection
        </code>
         is numbered within
        <code>
          section
        </code>
         so that any time you increment
        <var>
          section
        </var>
        , either with
        <code>
          \stepcounter
        </code>
         (
        <pxref label="_005cstepcounter">
          <xrefnodename>
            \stepcounter
          </xrefnodename>
        </pxref>
        ) or
        <code>
          \refstepcounter
        </code>
         (
        <pxref label="_005crefstepcounter">
          <xrefnodename>
            \refstepcounter
          </xrefnodename>
        </pxref>
        ), then
Default handler: &latex;
         will reset
        <var>
          subsection
        </var>
         to zero.
      </para>
      <para>
        This example
      </para>
      <example endspaces=" ">
        <pre xml:space="preserve">
          \newcounter
Default handler: &lbrace;
          asuper
Default handler: &rbrace;
           \setcounter
Default handler: &lbrace;
          asuper
Default handler: &rbrace;
Default handler: &lbrace;
          1
Default handler: &rbrace;
           \newcounter
Default handler: &lbrace;
          asub
Default handler: &rbrace;
          [asuper] \setcounter
Default handler: &lbrace;
          asub
Default handler: &rbrace;
Default handler: &lbrace;
          3
Default handler: &rbrace;
           % Note `asuper' The value of asuper is \arabic
Default handler: &lbrace;
          asuper
Default handler: &rbrace;
           and of asub is \arabic
Default handler: &lbrace;
          asub
Default handler: &rbrace;
          . \stepcounter
Default handler: &lbrace;
          asuper
Default handler: &rbrace;
           Now asuper is \arabic
Default handler: &lbrace;
          asuper
Default handler: &rbrace;
           while asub is \arabic
Default handler: &lbrace;
          asub
Default handler: &rbrace;
          .
        </pre>
      </example>
      <para>
        produces
        <samp>
          The value of asuper is 1 and that of asub is 3
        </samp>
         and
        <samp>
          Now asuper is 2 while asub is 0
        </samp>
        .
      </para>
      <para>
        If the counter already exists, for instance by entering
        <code>
          asuper
        </code>
         twice, then you get something like
        <samp>
          LaTeX Error: Command \c
Default handler: &arobase;
          asuper already defined. Or name \end... illegal, see p.192 of the manual.
        </samp>
        .
      </para>
      <para>
        If you use the optional argument then the super counter must already exist. Entering
        <code>
          \newcounter
Default handler: &lbrace;
          jh
Default handler: &rbrace;
          [lh]
        </code>
         when
        <code>
          lh
        </code>
         is not a defined counter will get you
        <samp>
          LaTeX Error: No counter 'lh' defined.
        </samp>
      </para>
    </section>
    <node name="_005cnewlength" spaces=" ">
      <nodename>
        \newlength
      </nodename>
      <nodenext automatic="on">
        \newsavebox
      </nodenext>
      <nodeprev automatic="on">
        \newcounter
      </nodeprev>
      <nodeup automatic="on">
        Definitions
      </nodeup>
    </node>
    <section spaces=" ">
      <sectiontitle>
        <code>
          \newlength
        </code>
      </sectiontitle>
      <findex index="fn" spaces=" ">
        <indexterm index="fn" number="497" mergedindex="cp">
          \newlength
        </indexterm>
      </findex>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="531">
          lengths, allocating new
        </indexterm>
      </cindex>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="532">
          rubber lengths, defining new
        </indexterm>
      </cindex>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="533">
          skip register, plain
Default handler: &tex;
        </indexterm>
      </cindex>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="534">
          glue register, plain
Default handler: &tex;
        </indexterm>
      </cindex>
      <para>
        Synopsis:
      </para>
      <example endspaces=" ">
        <pre xml:space="preserve">
          \newlength
Default handler: &lbrace;
          \
          <var>
            len
          </var>
Default handler: &rbrace;
        </pre>
      </example>
      <para>
        Allocate a new length register (
        <pxref label="Lengths">
          <xrefnodename>
            Lengths
          </xrefnodename>
        </pxref>
        ). The required argument
        <code>
          \
          <var>
            len
          </var>
        </code>
         has to be a control sequence (
        <pxref label="Control-sequences">
          <xrefnodename>
            Control sequences
          </xrefnodename>
        </pxref>
        ), and as such must begin with a backslash,
        <code>
          \
        </code>
         under normal circumstances. The new register holds rubber lengths such as
        <code>
          72.27pt
        </code>
         or
        <code>
          1in plus.2in minus.1in
        </code>
         (a
Default handler: &latex;
         length register is what plain
Default handler: &tex;
         calls a
        <code>
          skip
        </code>
         register). The initial value is zero. The control sequence
        <code>
          \
          <var>
            len
          </var>
        </code>
         must not be already defined.
      </para>
      <para>
        An example:
      </para>
      <example endspaces=" ">
        <pre xml:space="preserve">
          \newlength
Default handler: &lbrace;
          \graphichgt
Default handler: &rbrace;
        </pre>
      </example>
      <para>
        If you forget the backslash then you get
        <samp>
          Missing control sequence inserted
        </samp>
        . If the control sequence already exists then you get something like
        <samp>
          LaTeX Error: Command \graphichgt already defined. Or name \end... illegal, see p.192 of the manual
        </samp>
        .
      </para>
    </section>
    <node name="_005cnewsavebox" spaces=" ">
      <nodename>
        \newsavebox
      </nodename>
      <nodenext automatic="on">
        \newenvironment
        &
         \renewenvironment
      </nodenext>
      <nodeprev automatic="on">
        \newlength
      </nodeprev>
      <nodeup automatic="on">
        Definitions
      </nodeup>
    </node>
    <section spaces=" ">
      <sectiontitle>
        <code>
          \newsavebox
        </code>
      </sectiontitle>
      <findex index="fn" spaces=" ">
        <indexterm index="fn" number="498" mergedindex="cp">
          \newsavebox
        </indexterm>
      </findex>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="535">
          box, allocating new
        </indexterm>
      </cindex>
      <para>
        Synopsis:
      </para>
      <example endspaces=" ">
        <pre xml:space="preserve">
          \newsavebox
Default handler: &lbrace;
          \
          <var>
            cmd
          </var>
Default handler: &rbrace;
        </pre>
      </example>
      <para>
        Define \
        <var>
          cmd
        </var>
        , the string consisting of a backslash followed by
        <var>
          cmd
        </var>
        , to refer to a new bin for storing material. These bins hold material that has been typeset, to use multiple times or to measure or manipulate (
        <pxref label="Boxes">
          <xrefnodename>
            Boxes
          </xrefnodename>
        </pxref>
        ). The bin name \
        <var>
          cmd
        </var>
         is required, must start with a backslash, \, and must not already be a defined command. This command is fragile (
        <pxref label="_005cprotect">
          <xrefnodename>
            \protect
          </xrefnodename>
        </pxref>
        ).
      </para>
      <para>
        This allocates a bin and then puts typeset material into it.
      </para>
      <example endspaces=" ">
        <pre xml:space="preserve">
          \newsavebox
Default handler: &lbrace;
          \logobox
Default handler: &rbrace;
           \savebox
Default handler: &lbrace;
          \logobox
Default handler: &rbrace;
Default handler: &lbrace;
          LoGo
Default handler: &rbrace;
           Our logo is \usebox
Default handler: &lbrace;
          \logobox
Default handler: &rbrace;
          .
        </pre>
      </example>
      <noindent/>
      <para>
        The output is
        <samp>
          Our logo is LoGo
        </samp>
        .
      </para>
      <para>
        If there is an already defined bin then you get something like
        <samp>
          LaTeX Error: Command \logobox already defined. Or name \end... illegal, see p.192 of the manual
        </samp>
        .
      </para>
      <para>
        The allocation of a box is global.
      </para>
    </section>
    <node name="_005cnewenvironment-_0026-_005crenewenvironment" spaces=" ">
      <nodename>
        \newenvironment
        &
         \renewenvironment
      </nodename>
      <nodenext automatic="on">
        \newtheorem
      </nodenext>
      <nodeprev automatic="on">
        \newsavebox
      </nodeprev>
      <nodeup automatic="on">
        Definitions
      </nodeup>
    </node>
    <section spaces=" ">
      <sectiontitle>
        <code>
          \newenvironment
        </code>
        &
        <code>
          \renewenvironment
        </code>
      </sectiontitle>
      <anchor name="_005cnewenvironment">
        \newenvironment
      </anchor>
      <anchor name="_005crenewenvironment">
        \renewenvironment
      </anchor>
      <findex index="fn" spaces=" ">
        <indexterm index="fn" number="499" mergedindex="cp">
          \newenvironment
        </indexterm>
      </findex>
      <findex index="fn" spaces=" ">
        <indexterm index="fn" number="500" mergedindex="cp">
          \renewenvironment
        </indexterm>
      </findex>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="536">
          environments, defining
        </indexterm>
      </cindex>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="537">
          defining new environments
        </indexterm>
      </cindex>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="538">
          redefining environments
        </indexterm>
      </cindex>
      <para>
        Synopses, one of:
      </para>
      <example endspaces=" ">
        <pre xml:space="preserve">
          \newenvironment
Default handler: &lbrace;
          <var>
            env
          </var>
Default handler: &rbrace;
Default handler: &lbrace;
          <var>
            begdef
          </var>
Default handler: &rbrace;
Default handler: &lbrace;
          <var>
            enddef
          </var>
Default handler: &rbrace;
           \newenvironment
Default handler: &lbrace;
          <var>
            env
          </var>
Default handler: &rbrace;
          [
          <var>
            nargs
          </var>
          ]
Default handler: &lbrace;
          <var>
            begdef
          </var>
Default handler: &rbrace;
Default handler: &lbrace;
          <var>
            enddef
          </var>
Default handler: &rbrace;
           \newenvironment
Default handler: &lbrace;
          <var>
            env
          </var>
Default handler: &rbrace;
          [
          <var>
            nargs
          </var>
          ][
          <var>
            optargdefault
          </var>
          ]
Default handler: &lbrace;
          <var>
            begdef
          </var>
Default handler: &rbrace;
Default handler: &lbrace;
          <var>
            enddef
          </var>
Default handler: &rbrace;
           \newenvironment*
Default handler: &lbrace;
          <var>
            env
          </var>
Default handler: &rbrace;
Default handler: &lbrace;
          <var>
            begdef
          </var>
Default handler: &rbrace;
Default handler: &lbrace;
          <var>
            enddef
          </var>
Default handler: &rbrace;
           \newenvironment*
Default handler: &lbrace;
          <var>
            env
          </var>
Default handler: &rbrace;
          [
          <var>
            nargs
          </var>
          ]
Default handler: &lbrace;
          <var>
            begdef
          </var>
Default handler: &rbrace;
Default handler: &lbrace;
          <var>
            enddef
          </var>
Default handler: &rbrace;
           \newenvironment*
Default handler: &lbrace;
          <var>
            env
          </var>
Default handler: &rbrace;
          [
          <var>
            nargs
          </var>
          ][
          <var>
            optargdefault
          </var>
          ]
Default handler: &lbrace;
          <var>
            begdef
          </var>
Default handler: &rbrace;
Default handler: &lbrace;
          <var>
            enddef
          </var>
Default handler: &rbrace;
        </pre>
      </example>
      <noindent/>
      <para>
        or one of these.
      </para>
      <example endspaces=" ">
        <pre xml:space="preserve">
          \renewenvironment
Default handler: &lbrace;
          <var>
            env
          </var>
Default handler: &rbrace;
Default handler: &lbrace;
          <var>
            begdef
          </var>
Default handler: &rbrace;
Default handler: &lbrace;
          <var>
            enddef
          </var>
Default handler: &rbrace;
           \renewenvironment
Default handler: &lbrace;
          <var>
            env
          </var>
Default handler: &rbrace;
          [
          <var>
            nargs
          </var>
          ]
Default handler: &lbrace;
          <var>
            begdef
          </var>
Default handler: &rbrace;
Default handler: &lbrace;
          <var>
            enddef
          </var>
Default handler: &rbrace;
           \renewenvironment
Default handler: &lbrace;
          <var>
            env
          </var>
Default handler: &rbrace;
          [
          <var>
            nargs
          </var>
          ][
          <var>
            optargdefault
          </var>
          ]
Default handler: &lbrace;
          <var>
            begdef
          </var>
Default handler: &rbrace;
Default handler: &lbrace;
          <var>
            enddef
          </var>
Default handler: &rbrace;
           \renewenvironment*
Default handler: &lbrace;
          <var>
            env
          </var>
Default handler: &rbrace;
Default handler: &lbrace;
          <var>
            begdef
          </var>
Default handler: &rbrace;
Default handler: &lbrace;
          <var>
            enddef
          </var>
Default handler: &rbrace;
           \renewenvironment*
Default handler: &lbrace;
          <var>
            env
          </var>
Default handler: &rbrace;
          [
          <var>
            nargs
          </var>
          ]
Default handler: &lbrace;
          <var>
            begdef
          </var>
Default handler: &rbrace;
Default handler: &lbrace;
          <var>
            enddef
          </var>
Default handler: &rbrace;
           \renewenvironment*
Default handler: &lbrace;
          <var>
            env
          </var>
Default handler: &rbrace;
          [
          <var>
            nargs
          </var>
          ][
          <var>
            optargdefault
          </var>
          ]
Default handler: &lbrace;
          <var>
            begdef
          </var>
Default handler: &rbrace;
Default handler: &lbrace;
          <var>
            enddef
          </var>
Default handler: &rbrace;
        </pre>
      </example>
      <para>
        Define or redefine the environment
        <var>
          env
        </var>
        , that is, create the construct
        <code>
          \begin
Default handler: &lbrace;
          <var>
            env
          </var>
Default handler: &rbrace;
           ...
          <var>
            body
          </var>
           ... \end
Default handler: &lbrace;
          <var>
            env
          </var>
Default handler: &rbrace;
        </code>
        .
      </para>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="539">
          <code>
            *
          </code>
          -form of environment commands
        </indexterm>
      </cindex>
      <para>
        The starred form of these commands requires that the arguments not contain multiple paragraphs of text. However, the body of these environments can contain multiple paragraphs.
      </para>
      <table commandarg="var" spaces=" " endspaces=" ">
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="var">
                env
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <para>
              Required; the environment name. It consists only of letters or the
              <code>
                *
              </code>
               character, and thus does not begin with backslash,
              <code>
                \
              </code>
              . It must not begin with the string
              <code>
                end
              </code>
              . For
              <code>
                \newenvironment
              </code>
              , the name
              <var>
                env
              </var>
               must not be the name of an already existing environment, and also the command
              <code>
                \
                <var>
                  env
                </var>
              </code>
               must be undefined. For
              <code>
                \renewenvironment
              </code>
              ,
              <var>
                env
              </var>
               must be the name of an existing environment.
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="var">
                nargs
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <para>
              Optional; an integer from 0 to 9 denoting the number of arguments of that the environment takes. When you use the environment these arguments appear after the
              <code>
                \begin
              </code>
              , as in
              <code>
                \begin
Default handler: &lbrace;
                <var>
                  env
                </var>
Default handler: &rbrace;
Default handler: &lbrace;
                <var>
                  arg1
                </var>
Default handler: &rbrace;
                 ...
Default handler: &lbrace;
                <var>
                  argn
                </var>
Default handler: &rbrace;
              </code>
              . Omitting this is equivalent to setting it to 0; the environment will have no arguments. When redefining an environment, the new version can have a different number of arguments than the old version.
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="var">
                optargdefault
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <para>
              Optional; if this is present then the first argument of the defined environment is optional, with default value
              <var>
                optargdefault
              </var>
               (which may be the empty string). If this is not in the definition then the environment does not take an optional argument.
            </para>
            <para>
              That is, when
              <var>
                optargdefault
              </var>
               is present in the definition of the environment then you can start the environment with square brackets, as in
              <code>
                \begin
Default handler: &lbrace;
                <var>
                  env
                </var>
Default handler: &rbrace;
                [
                <var>
                  optval
                </var>
                ]
Default handler: &lbrace;
                ...
Default handler: &rbrace;
                 ... \end
Default handler: &lbrace;
                <var>
                  env
                </var>
Default handler: &rbrace;
              </code>
              . In this case, within
              <var>
                begdefn
              </var>
               the parameter
              <code>
                #1
              </code>
               is set to the value of
              <var>
                optval
              </var>
              . If you call
              <code>
                \begin
Default handler: &lbrace;
                <var>
                  env
                </var>
Default handler: &rbrace;
              </code>
               without square brackets, then within
              <var>
                begdefn
              </var>
               the parameter
              <code>
                #1
              </code>
               is set to the value of the default
              <var>
                optargdefault
              </var>
              . In either case, any required arguments start with
              <code>
                #2
              </code>
              .
            </para>
            <para>
              Omitting
              <code>
                [
                <var>
                  myval
                </var>
                ]
              </code>
               in the call is different than having the square brackets with no contents, as in
              <code>
                []
              </code>
              . The former results in
              <code>
                #1
              </code>
               expanding to
              <var>
                optargdefault
              </var>
              ; the latter results in
              <code>
                #1
              </code>
               expanding to the empty string.
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="var">
                begdef
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <para>
              Required; the text expanded at every occurrence of
              <code>
                \begin
Default handler: &lbrace;
                <var>
                  env
                </var>
Default handler: &rbrace;
              </code>
              . Within
              <var>
                begdef
              </var>
              , the parameters
              <code>
                #1
              </code>
              ,
              <code>
                #2
              </code>
              , ...
              <code>
                #
                <var>
                  nargs
                </var>
              </code>
              , are replaced by the values that you supply when you call the environment; see the examples below.
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="var">
                enddef
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <para>
              Required; the text expanded at every occurrence of
              <code>
                \end
Default handler: &lbrace;
                <var>
                  env
                </var>
Default handler: &rbrace;
              </code>
              . This may not contain any parameters, that is, you cannot use
              <code>
                #1
              </code>
              ,
              <code>
                #2
              </code>
              , etc., here (but see the final example below).
            </para>
          </tableitem>
        </tableentry>
      </table>
      <para>
        All environments, that is to say the
        <var>
          begdef
        </var>
         code, the environment body, and the
        <var>
          enddef
        </var>
         code, are processed within a group. Thus, in the first example below, the effect of the
        <code>
          \small
        </code>
         is limited to the quote and does not extend to material following the environment.
      </para>
      <para>
        If you try to define an environment and the name has already been used then you get something like
        <samp>
          LaTeX Error: Command \fred already defined. Or name \end... illegal, see p.192 of the manual
        </samp>
        . If you try to redefine an environment and the name has not yet been used then you get something like
        <samp>
          LaTeX Error: Environment hank undefined.
        </samp>
        .
      </para>
      <para>
        This example gives an environment like
Default handler: &latex;
Default handler: &textrsquo;
        s
        <code>
          quotation
        </code>
         except that it will be set in smaller type.
      </para>
      <example endspaces=" ">
        <pre xml:space="preserve">
          \newenvironment
Default handler: &lbrace;
          smallquote
Default handler: &rbrace;
Default handler: &lbrace;
          % \small\begin
Default handler: &lbrace;
          quotation
Default handler: &rbrace;
Default handler: &rbrace;
Default handler: &lbrace;
          % \end
Default handler: &lbrace;
          quotation
Default handler: &rbrace;
Default handler: &rbrace;
        </pre>
      </example>
      <para>
        This has an argument, which is set in boldface at the start of a paragraph.
      </para>
      <example endspaces=" ">
        <pre xml:space="preserve">
          \newenvironment
Default handler: &lbrace;
          point
Default handler: &rbrace;
          [1]
Default handler: &lbrace;
          % \noindent\textbf
Default handler: &lbrace;
          #1
Default handler: &rbrace;
Default handler: &rbrace;
Default handler: &lbrace;
          %
Default handler: &rbrace;
        </pre>
      </example>
      <para>
        This one shows the use of a optional argument; it gives a quotation environment that cites the author.
      </para>
      <example endspaces=" ">
        <pre xml:space="preserve">
          \newenvironment
Default handler: &lbrace;
          citequote
Default handler: &rbrace;
          [1][Shakespeare]
Default handler: &lbrace;
          % \begin
Default handler: &lbrace;
          quotation
Default handler: &rbrace;
           \noindent\textit
Default handler: &lbrace;
          #1
Default handler: &rbrace;
          :
Default handler: &rbrace;
Default handler: &lbrace;
          % \end
Default handler: &lbrace;
          quotation
Default handler: &rbrace;
Default handler: &rbrace;
        </pre>
      </example>
      <noindent/>
      <para>
        The author
Default handler: &textrsquo;
        s name is optional, and defaults to
        <samp>
          Shakespeare
        </samp>
        . In the document, use the environment like this.
      </para>
      <example endspaces=" ">
        <pre xml:space="preserve">
          \begin
Default handler: &lbrace;
          citequote
Default handler: &rbrace;
          [Lincoln] ... \end
Default handler: &lbrace;
          citequote
Default handler: &rbrace;
        </pre>
      </example>
      <para>
        The final example shows how to save the value of an argument to use in
        <var>
          enddef
        </var>
        , in this case in a box (
        <pxref label="_005csbox-_0026-_005csavebox">
          <xrefnodename>
            \sbox
            &
             \savebox
          </xrefnodename>
        </pxref>
        ).
      </para>
      <example endspaces=" ">
        <pre xml:space="preserve">
          \newsavebox
Default handler: &lbrace;
          \quoteauthor
Default handler: &rbrace;
           \newenvironment
Default handler: &lbrace;
          citequote
Default handler: &rbrace;
          [1][Shakespeare]
Default handler: &lbrace;
          % \sbox\quoteauthor
Default handler: &lbrace;
          #1
Default handler: &rbrace;
          % \begin
Default handler: &lbrace;
          quotation
Default handler: &rbrace;
Default handler: &rbrace;
Default handler: &lbrace;
          % \hspace
Default handler: &lbrace;
          1em plus 1fill
Default handler: &rbrace;
          ---\usebox
Default handler: &lbrace;
          \quoteauthor
Default handler: &rbrace;
           \end
Default handler: &lbrace;
          quotation
Default handler: &rbrace;
Default handler: &rbrace;
        </pre>
      </example>
    </section>
    <node name="_005cnewtheorem" spaces=" ">
      <nodename>
        \newtheorem
      </nodename>
      <nodenext automatic="on">
        \newfont
      </nodenext>
      <nodeprev automatic="on">
        \newenvironment
        &
         \renewenvironment
      </nodeprev>
      <nodeup automatic="on">
        Definitions
      </nodeup>
    </node>
    <section spaces=" ">
      <sectiontitle>
        <code>
          \newtheorem
        </code>
      </sectiontitle>
      <findex index="fn" spaces=" ">
        <indexterm index="fn" number="501" mergedindex="cp">
          \newtheorem
        </indexterm>
      </findex>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="540">
          theorems, defining
        </indexterm>
      </cindex>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="541">
          defining new theorems
        </indexterm>
      </cindex>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="542">
          theorem-like environment
        </indexterm>
      </cindex>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="543">
          environment, theorem-like
        </indexterm>
      </cindex>
      <para>
        Synopses:
      </para>
      <example endspaces=" ">
        <pre xml:space="preserve">
          \newtheorem
Default handler: &lbrace;
          <var>
            name
          </var>
Default handler: &rbrace;
Default handler: &lbrace;
          <var>
            title
          </var>
Default handler: &rbrace;
           \newtheorem
Default handler: &lbrace;
          <var>
            name
          </var>
Default handler: &rbrace;
Default handler: &lbrace;
          <var>
            title
          </var>
Default handler: &rbrace;
          [
          <var>
            numbered_within
          </var>
          ] \newtheorem
Default handler: &lbrace;
          <var>
            name
          </var>
Default handler: &rbrace;
          [
          <var>
            numbered_like
          </var>
          ]
Default handler: &lbrace;
          <var>
            title
          </var>
Default handler: &rbrace;
        </pre>
      </example>
      <para>
        Define a new theorem-like environment. You can specify one of
        <var>
          numbered_within
        </var>
         and
        <var>
          numbered_like
        </var>
        , or neither, but not both.
      </para>
      <para>
        The first form,
        <code>
          \newtheorem
Default handler: &lbrace;
          <var>
            name
          </var>
Default handler: &rbrace;
Default handler: &lbrace;
          <var>
            title
          </var>
Default handler: &rbrace;
        </code>
        , creates an environment that will be labelled with
        <var>
          title
        </var>
        ; see the first example below.
      </para>
      <para>
        The second form,
        <code>
          \newtheorem
Default handler: &lbrace;
          <var>
            name
          </var>
Default handler: &rbrace;
Default handler: &lbrace;
          <var>
            title
          </var>
Default handler: &rbrace;
          [
          <var>
            numbered_within
          </var>
          ]
        </code>
        , creates an environment whose counter is subordinate to the existing counter
        <var>
          numbered_within
        </var>
        , so this counter will be reset when
        <var>
          numbered_within
        </var>
         is reset. See the second example below.
      </para>
      <para>
        The third form
        <code>
          \newtheorem
Default handler: &lbrace;
          <var>
            name
          </var>
Default handler: &rbrace;
          [
          <var>
            numbered_like
          </var>
          ]
Default handler: &lbrace;
          <var>
            title
          </var>
Default handler: &rbrace;
        </code>
        , with optional argument between the two required arguments, creates an environment whose counter will share the previously defined counter
        <var>
          numbered_like
        </var>
        . See the third example.
      </para>
      <para>
        This command creates a counter named
        <var>
          name
        </var>
        . In addition, unless the optional argument
        <var>
          numbered_like
        </var>
         is used, inside of the theorem-like environment the current
        <code>
          \ref
        </code>
         value will be that of
        <code>
          \the
          <var>
            numbered_within
          </var>
        </code>
         (
        <pxref label="_005cref">
          <xrefnodename>
            \ref
          </xrefnodename>
        </pxref>
        ).
      </para>
      <para>
        This declaration is global. It is fragile (
        <pxref label="_005cprotect">
          <xrefnodename>
            \protect
          </xrefnodename>
        </pxref>
        ).
      </para>
      <para>
        Arguments:
      </para>
      <table commandarg="var" spaces=" " endspaces=" ">
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="var">
                name
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <para>
              The name of the environment. It is a string of letters. It must not begin with a backslash,
              <code>
                \
              </code>
              . It must not be the name of an existing environment, and the command name
              <code>
                \
                <var>
                  name
                </var>
              </code>
               must not already be defined.
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="var">
                title
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <para>
              The text to be printed at the beginning of the environment, before the number. For example,
              <samp>
                Theorem
              </samp>
              .
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="var">
                numbered_within
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <para>
              Optional; the name of an already defined counter, usually a sectional unit such as
              <code>
                chapter
              </code>
               or
              <code>
                section
              </code>
              . When the
              <var>
                numbered_within
              </var>
               counter is reset then the
              <var>
                name
              </var>
               environment
Default handler: &textrsquo;
              s counter will also be reset.
            </para>
            <para>
              If this optional argument is not used then the command
              <code>
                \the
                <var>
                  name
                </var>
              </code>
               is set to
              <code>
                \arabic
Default handler: &lbrace;
                <var>
                  name
                </var>
Default handler: &rbrace;
              </code>
              .
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="var">
                numbered_like
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <para>
              Optional; the name of an already defined theorem-like environment. The new environment will be numbered in sequence with
              <var>
                numbered_like
              </var>
              .
            </para>
          </tableitem>
        </tableentry>
      </table>
      <para>
        Without any optional arguments the environments are numbered sequentially. The example below has a declaration in the preamble that results in
        <samp>
          Definition
Default handler: &nbsp;
          1
        </samp>
         and
        <samp>
          Definition
Default handler: &nbsp;
          2
        </samp>
         in the output.
      </para>
      <example endspaces=" ">
        <pre xml:space="preserve">
          \newtheorem
Default handler: &lbrace;
          defn
Default handler: &rbrace;
Default handler: &lbrace;
          Definition
Default handler: &rbrace;
           \begin
Default handler: &lbrace;
          document
Default handler: &rbrace;
           \section
Default handler: &lbrace;
          ...
Default handler: &rbrace;
           \begin
Default handler: &lbrace;
          defn
Default handler: &rbrace;
           First def \end
Default handler: &lbrace;
          defn
Default handler: &rbrace;
           \section
Default handler: &lbrace;
          ...
Default handler: &rbrace;
           \begin
Default handler: &lbrace;
          defn
Default handler: &rbrace;
           Second def \end
Default handler: &lbrace;
          defn
Default handler: &rbrace;
        </pre>
      </example>
      <para>
        This example has the same document body as the prior one. But here
        <code>
          \newtheorem
        </code>
Default handler: &textrsquo;
        s optional argument
        <var>
          numbered_within
        </var>
         is given as
        <code>
          section
        </code>
        , so the output is like
        <samp>
          Definition
Default handler: &nbsp;
          1.1
        </samp>
         and
        <samp>
          Definition
Default handler: &nbsp;
          2.1
        </samp>
        .
      </para>
      <example endspaces=" ">
        <pre xml:space="preserve">
          \newtheorem
Default handler: &lbrace;
          defn
Default handler: &rbrace;
Default handler: &lbrace;
          Definition
Default handler: &rbrace;
          [section] \begin
Default handler: &lbrace;
          document
Default handler: &rbrace;
           \section
Default handler: &lbrace;
          ...
Default handler: &rbrace;
           \begin
Default handler: &lbrace;
          defn
Default handler: &rbrace;
           First def \end
Default handler: &lbrace;
          defn
Default handler: &rbrace;
           \section
Default handler: &lbrace;
          ...
Default handler: &rbrace;
           \begin
Default handler: &lbrace;
          defn
Default handler: &rbrace;
           Second def \end
Default handler: &lbrace;
          defn
Default handler: &rbrace;
        </pre>
      </example>
      <para>
        In the next example there are two declarations in the preamble, the second of which calls for the new
        <code>
          thm
        </code>
         environment to use the same counter as
        <code>
          defn
        </code>
        . It gives
        <samp>
          Definition
Default handler: &nbsp;
          1.1
        </samp>
        , followed by
        <samp>
          Theorem
Default handler: &nbsp;
          2.1
        </samp>
         and
        <samp>
          Definition
Default handler: &nbsp;
          2.2
        </samp>
        .
      </para>
      <example endspaces=" ">
        <pre xml:space="preserve">
          \newtheorem
Default handler: &lbrace;
          defn
Default handler: &rbrace;
Default handler: &lbrace;
          Definition
Default handler: &rbrace;
          [section] \newtheorem
Default handler: &lbrace;
          thm
Default handler: &rbrace;
          [defn]
Default handler: &lbrace;
          Theorem
Default handler: &rbrace;
           \begin
Default handler: &lbrace;
          document
Default handler: &rbrace;
           \section
Default handler: &lbrace;
          ...
Default handler: &rbrace;
           \begin
Default handler: &lbrace;
          defn
Default handler: &rbrace;
           First def \end
Default handler: &lbrace;
          defn
Default handler: &rbrace;
           \section
Default handler: &lbrace;
          ...
Default handler: &rbrace;
           \begin
Default handler: &lbrace;
          thm
Default handler: &rbrace;
           First thm \end
Default handler: &lbrace;
          thm
Default handler: &rbrace;
           \begin
Default handler: &lbrace;
          defn
Default handler: &rbrace;
           Second def \end
Default handler: &lbrace;
          defn
Default handler: &rbrace;
        </pre>
      </example>
    </section>
    <node name="_005cnewfont" spaces=" ">
      <nodename>
        \newfont
      </nodename>
      <nodenext automatic="on">
        \protect
      </nodenext>
      <nodeprev automatic="on">
        \newtheorem
      </nodeprev>
      <nodeup automatic="on">
        Definitions
      </nodeup>
    </node>
    <section spaces=" ">
      <sectiontitle>
        <code>
          \newfont
        </code>
      </sectiontitle>
      <findex index="fn" spaces=" ">
        <indexterm index="fn" number="502" mergedindex="cp">
          \newfont
        </indexterm>
      </findex>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="544">
          fonts, new commands for
        </indexterm>
      </cindex>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="545">
          defining new fonts
        </indexterm>
      </cindex>
Default handler: <!-- c @findex .fd @r{file} -->
      <para>
        This command is obsolete. This description is here only to help with old documents. New documents should define fonts in families through the New Font Selection Scheme which allows you to, for example, associate a boldface with a roman (
        <pxref label="Fonts">
          <xrefnodename>
            Fonts
          </xrefnodename>
        </pxref>
        ).
Default handler: <!-- c This is done either by using -->
Default handler: <!-- c @file{.fd} files or through the use of an engine that can access system -->
Default handler: <!-- c fonts such as Xe@LaTeX{} (@pxref{@TeX{} engines}). -->
      </para>
      <para>
        Synopsis:
      </para>
      <example endspaces=" ">
        <pre xml:space="preserve">
          \newfont
Default handler: &lbrace;
          \
          <var>
            cmd
          </var>
Default handler: &rbrace;
Default handler: &lbrace;
          <var>
            font description
          </var>
Default handler: &rbrace;
        </pre>
      </example>
      <para>
        Define a command
        <code>
          \
          <var>
            cmd
          </var>
        </code>
         that will change the current font. The control sequence must not already be defined. It must begin with a backslash,
        <code>
          \
        </code>
        .
      </para>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="546">
          at clause, in font definitions
        </indexterm>
      </cindex>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="547">
          design size, in font definitions
        </indexterm>
      </cindex>
      <para>
        The
        <var>
          font description
        </var>
         consists of a
        <var>
          fontname
        </var>
         and an optional
        <dfn>
          at clause
        </dfn>
        .
Default handler: &latex;
         will look on your system for a file named
        <file>
          <var>
            fontname
          </var>
          .tfm
        </file>
        . The at clause can have the form either
        <code>
          at
          <var>
            dimen
          </var>
        </code>
         or
        <code>
          scaled
          <var>
            factor
          </var>
        </code>
        , where a
        <var>
          factor
        </var>
         of
        <samp>
          1000
        </samp>
         means no scaling. For
Default handler: &latex;
Default handler: &textrsquo;
        s purposes, all this does is scale all the character and other font dimensions relative to the font
Default handler: &textrsquo;
        s design size, which is a value defined in the
        <file>
          .tfm
        </file>
         file.
      </para>
      <para>
        This defines two equivalent fonts and typesets a few characters in each.
      </para>
      <example endspaces=" ">
        <pre xml:space="preserve">
          \newfont
Default handler: &lbrace;
          \testfontat
Default handler: &rbrace;
Default handler: &lbrace;
          cmb10 at 11pt
Default handler: &rbrace;
           \newfont
Default handler: &lbrace;
          \testfontscaled
Default handler: &rbrace;
Default handler: &lbrace;
          cmb10 scaled 1100
Default handler: &rbrace;
           \testfontat abc \testfontscaled abc
        </pre>
      </example>
    </section>
    <node name="_005cprotect" spaces=" ">
      <nodename>
        \protect
      </nodename>
      <nodenext automatic="on">
        \ignorespaces
        &
         \ignorespacesafterend
      </nodenext>
      <nodeprev automatic="on">
        \newfont
      </nodeprev>
      <nodeup automatic="on">
        Definitions
      </nodeup>
    </node>
    <section spaces=" ">
      <sectiontitle>
        <code>
          \protect
        </code>
      </sectiontitle>
      <findex index="fn" spaces=" ">
        <indexterm index="fn" number="503" mergedindex="cp">
          \protect
        </indexterm>
      </findex>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="548">
          fragile commands
        </indexterm>
      </cindex>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="549">
          robust commands
        </indexterm>
      </cindex>
      <para>
        All
Default handler: &latex;
         commands are either
        <dfn>
          fragile
        </dfn>
         or
        <dfn>
          robust
        </dfn>
        . A fragile command can break when it is used in the argument to certain other commands, typically those that write material to the table of contents, the cross-reference file, etc. To prevent fragile commands from causing errors, one solution is to precede them with the command
        <code>
          \protect
        </code>
        .
      </para>
      <para>
        For example, when
Default handler: &latex;
         runs the
        <code>
          \section
Default handler: &lbrace;
          <var>
            section name
          </var>
Default handler: &rbrace;
        </code>
         command it writes the
        <var>
          section name
        </var>
         text to the
        <file>
          .aux
        </file>
         auxiliary file, moving it there for use elsewhere in the document such as in the table of contents. Such an argument that is used in multiple places is referred to as a
        <cindex index="cp" spaces=" ">
          <indexterm index="cp" number="550">
            moving arguments
          </indexterm>
        </cindex>
        <dfn>
          moving argument
        </dfn>
        . A command is fragile if it can expand during this process into invalid
Default handler: &tex;
         code. Some examples of moving arguments are those that appear in the
        <code>
          \caption
Default handler: &lbrace;
          ...
Default handler: &rbrace;
        </code>
         command (
        <pxref label="figure">
          <xrefnodename>
            figure
          </xrefnodename>
        </pxref>
        ), in the
        <code>
          \thanks
Default handler: &lbrace;
          ...
Default handler: &rbrace;
        </code>
         command (
        <pxref label="_005cmaketitle">
          <xrefnodename>
            \maketitle
          </xrefnodename>
        </pxref>
        ), and in
Default handler: &arobase;
        -expressions in the
        <code>
          tabular
        </code>
         and
        <code>
          array
        </code>
         environments (
        <pxref label="tabular">
          <xrefnodename>
            tabular
          </xrefnodename>
        </pxref>
        ).
      </para>
      <para>
        If you get strange errors from commands used in moving arguments, try preceding it with
        <code>
          \protect
        </code>
        . Each fragile command must be protected with their own
        <code>
          \protect
        </code>
        .
      </para>
      <para>
        Although usually a
        <code>
          \protect
        </code>
         command doesn
Default handler: &textrsquo;
        t hurt, length commands such as
        <code>
          \parindent
        </code>
         should not be preceded by a
        <code>
          \protect
        </code>
         command (
        <pxref label="Lengths">
          <xrefnodename>
            Lengths
          </xrefnodename>
        </pxref>
        . Nor can a
        <code>
          \protect
        </code>
         command be used in the argument to
        <code>
          \addtocounter
        </code>
         or
        <code>
          \setcounter
        </code>
         command (
        <pxref label="_005csetcounter">
          <xrefnodename>
            \setcounter
          </xrefnodename>
        </pxref>
         and
        <ref label="_005caddtocounter">
          <xrefnodename>
            \addtocounter
          </xrefnodename>
        </ref>
        . These commands are already robust.
      </para>
      <para>
        As of the October 2019 release of
Default handler: &latex;
         (
        <url>
          <urefurl>
            https://www.latex-project.org/news/latex2e-news/ltnews30.pdf
          </urefurl>
        </url>
        ), most commands that had been previously fragile were fixed to be robust. For example, any command taking an optional argument, such as
        <code>
          \root
        </code>
         or
        <code>
          \raisebox
        </code>
        , was fragile, but is now robust. Similarly,
        <code>
          \(...\)
        </code>
         math was fragile and is now robust (
        <code>
          $...$
        </code>
         has always been robust).
      </para>
      <findex index="fn" spaces=" ">
        <indexterm index="fn" number="504" mergedindex="cp">
          \verb
          <r>
            , as fragile command
          </r>
        </indexterm>
      </findex>
      <para>
        Perhaps the most commonly used remaining fragile command is
        <code>
          \verb
        </code>
        ; for example,
      </para>
      <example endspaces=" ">
        <pre xml:space="preserve">
          \begin
Default handler: &lbrace;
          figure
Default handler: &rbrace;
           ... \caption
Default handler: &lbrace;
          This \verb|\command| causes an error.
Default handler: &rbrace;
           \end
Default handler: &lbrace;
          figure
Default handler: &rbrace;
        </pre>
      </example>
      <para>
        Adding
        <code>
          \protect
        </code>
         does not help here. It
Default handler: &textrsquo;
        s usually feasible to rewrite the caption (or section heading or whatever) to use
        <code>
          \texttt
        </code>
        , often the simplest solution.
      </para>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="551">
          <r>
            package
          </r>
          ,
          <code>
            cprotect
          </code>
        </indexterm>
      </cindex>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="552">
          <code>
            cprotect
          </code>
          <r>
            package
          </r>
        </indexterm>
      </cindex>
      <findex index="fn" spaces=" ">
        <indexterm index="fn" number="505" mergedindex="cp">
          \cprotect
        </indexterm>
      </findex>
      <para>
        Alternatively, to use
        <code>
          \verb
        </code>
        , you can apply the
        <code>
          \cprotect
        </code>
         command from
        <code>
          cprotect
        </code>
         package (
        <url>
          <urefurl>
            https://ctan.org/pkg/cprotect
          </urefurl>
        </url>
        ) to the
        <code>
          \caption
        </code>
        :
      </para>
      <example endspaces=" ">
        <pre xml:space="preserve">
          \cprotect\caption
Default handler: &lbrace;
          This \verb|\command| is ok with \verb|\cprotect|.
Default handler: &rbrace;
        </pre>
      </example>
      <findex index="fn" spaces=" ">
        <indexterm index="fn" number="506" mergedindex="cp">
          \cprotEnv
        </indexterm>
      </findex>
      <para>
        <code>
          \cprotect
        </code>
         also allows use of
        <code>
          \begin...\end
        </code>
         environments in moving arguments, where they are normally not allowed, via a similar prefix command
        <code>
          \cprotEnv
        </code>
        .
      </para>
    </section>
    <node name="_005cignorespaces-_0026-_005cignorespacesafterend" spaces=" ">
      <nodename>
        \ignorespaces
        &
         \ignorespacesafterend
      </nodename>
      <nodenext automatic="on">
        xspace package
      </nodenext>
      <nodeprev automatic="on">
        \protect
      </nodeprev>
      <nodeup automatic="on">
        Definitions
      </nodeup>
    </node>
    <section spaces=" ">
      <sectiontitle>
        <code>
          \ignorespaces
          &
           \ignorespacesafterend
        </code>
      </sectiontitle>
      <anchor name="_005cignorespaces">
        \ignorespaces
      </anchor>
      <anchor name="_005cignorespacesafterend">
        \ignorespacesafterend
      </anchor>
      <findex index="fn" spaces=" ">
        <indexterm index="fn" number="507" mergedindex="cp">
          \ignorespaces
        </indexterm>
      </findex>
      <findex index="fn" spaces=" ">
        <indexterm index="fn" number="508" mergedindex="cp">
          \ignorespacesafterend
        </indexterm>
      </findex>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="553">
          spaces, ignore around commands
        </indexterm>
      </cindex>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="554">
          commands, ignore spaces
        </indexterm>
      </cindex>
      <para>
        Synopsis:
      </para>
      <example endspaces=" ">
        <pre xml:space="preserve">
          \ignorespaces
        </pre>
      </example>
      <noindent/>
      <para>
        or
      </para>
      <example endspaces=" ">
        <pre xml:space="preserve">
          \ignorespacesafterend
        </pre>
      </example>
      <para>
        Both commands cause
Default handler: &latex;
         to ignore blanks (that is, characters of catcode
Default handler: &nbsp;
        10 such as space or tabulation) after the end of the command up to the first box or non-blank character. The first is a primitive command of
Default handler: &tex;
        , and the second is
Default handler: &latex;
        -specific.
      </para>
      <para>
        The
        <code>
          \ignorespaces
        </code>
         is often used when defining commands via
        <code>
          \newcommand
        </code>
        , or
        <code>
          \newenvironment
        </code>
        , or
        <code>
          \def
        </code>
        . The example below illustrates. It allows a user to show the points values for quiz questions in the margin but it is inconvenient because, as shown in the
        <code>
          enumerate
        </code>
         list, users must not put any space between the command and the question text.
      </para>
      <example endspaces=" ">
        <pre xml:space="preserve">
          \newcommand
Default handler: &lbrace;
          \points
Default handler: &rbrace;
          [1]
Default handler: &lbrace;
          \makebox[0pt]
Default handler: &lbrace;
          \makebox[10em][l]
Default handler: &lbrace;
          #1~pts
Default handler: &rbrace;
Default handler: &rbrace;
           \begin
Default handler: &lbrace;
          enumerate
Default handler: &rbrace;
           \item\points
Default handler: &lbrace;
          10
Default handler: &rbrace;
          no extra space output here \item\points
Default handler: &lbrace;
          15
Default handler: &rbrace;
           extra space between the number and the `extra' \end
Default handler: &lbrace;
          enumerate
Default handler: &rbrace;
        </pre>
      </example>
      <noindent/>
      <para>
        The solution is to change to this.
      </para>
      <example endspaces=" ">
        <pre xml:space="preserve">
          \newcommand
Default handler: &lbrace;
          \points
Default handler: &rbrace;
          [1]
Default handler: &lbrace;
          % \makebox[0pt]
Default handler: &lbrace;
          \makebox[10em][l]
Default handler: &lbrace;
          #1~pts
Default handler: &rbrace;
Default handler: &rbrace;
          \ignorespaces
Default handler: &rbrace;
        </pre>
      </example>
      <para>
        A second example shows blanks being removed from the front of text. The commands below allow a user to uniformly attach a title to names. But, as given, if a title accidentally starts with a space then
        <code>
          \fullname
        </code>
         will reproduce that.
      </para>
      <example endspaces=" ">
        <pre xml:space="preserve">
          \newcommand
Default handler: &lbrace;
          \honorific
Default handler: &rbrace;
          [1]
Default handler: &lbrace;
          \def\honorific
Default handler: &lbrace;
          #1
Default handler: &rbrace;
Default handler: &rbrace;
           % remember title \newcommand
Default handler: &lbrace;
          \fullname
Default handler: &rbrace;
          [1]
Default handler: &lbrace;
          \honorific~#1
Default handler: &rbrace;
           % put title before name \begin
Default handler: &lbrace;
          tabular
Default handler: &rbrace;
Default handler: &lbrace;
          |l|
Default handler: &rbrace;
           \honorific
Default handler: &lbrace;
          Mr/Ms
Default handler: &rbrace;
           \fullname
Default handler: &lbrace;
          Jones
Default handler: &rbrace;
           \\ % no extra space here \honorific
Default handler: &lbrace;
           Mr/Ms
Default handler: &rbrace;
           \fullname
Default handler: &lbrace;
          Jones
Default handler: &rbrace;
           % extra space before title \end
Default handler: &lbrace;
          tabular
Default handler: &rbrace;
        </pre>
      </example>
      <noindent/>
      <para>
        To fix this, change to
        <code>
          \newcommand
Default handler: &lbrace;
          \fullname
Default handler: &rbrace;
          [1]
Default handler: &lbrace;
          \ignorespaces\honorific~#1
Default handler: &rbrace;
        </code>
        .
      </para>
      <para>
        The
        <code>
          \ignorespaces
        </code>
         is also often used in a
        <code>
          \newenvironment
        </code>
         at the end of the
        <var>
          begin
        </var>
         clause, as in
        <code>
          \begin
Default handler: &lbrace;
          newenvironment
Default handler: &rbrace;
Default handler: &lbrace;
          <var>
            env name
          </var>
Default handler: &rbrace;
Default handler: &lbrace;
          ... \ignorespaces
Default handler: &rbrace;
Default handler: &lbrace;
          ...
Default handler: &rbrace;
        </code>
        .
      </para>
      <para>
        To strip blanks off the end of an environment use
        <code>
          \ignorespacesafterend
        </code>
        . An example is that this will show a much larger vertical space between the first and second environments than between the second and third.
      </para>
      <example endspaces=" ">
        <pre xml:space="preserve">
          \newenvironment
Default handler: &lbrace;
          eq
Default handler: &rbrace;
Default handler: &lbrace;
          \begin
Default handler: &lbrace;
          equation
Default handler: &rbrace;
Default handler: &rbrace;
Default handler: &lbrace;
          \end
Default handler: &lbrace;
          equation
Default handler: &rbrace;
Default handler: &rbrace;
           \begin
Default handler: &lbrace;
          eq
Default handler: &rbrace;
           e=mc^2 \end
Default handler: &lbrace;
          eq
Default handler: &rbrace;
           \begin
Default handler: &lbrace;
          equation
Default handler: &rbrace;
           F=ma \end
Default handler: &lbrace;
          equation
Default handler: &rbrace;
           \begin
Default handler: &lbrace;
          equation
Default handler: &rbrace;
           E=IR \end
Default handler: &lbrace;
          equation
Default handler: &rbrace;
        </pre>
      </example>
      <para>
        Putting a comment character
Default handler: &nbsp;
        <code>
          %
        </code>
         immediately after the
        <code>
          \end
Default handler: &lbrace;
          eq
Default handler: &rbrace;
        </code>
         will make the vertical space disappear, but that is inconvenient. The solution is to change to
        <code>
          \newenvironment
Default handler: &lbrace;
          eq
Default handler: &rbrace;
Default handler: &lbrace;
          \begin
Default handler: &lbrace;
          equation
Default handler: &rbrace;
Default handler: &rbrace;
Default handler: &lbrace;
          \end
Default handler: &lbrace;
          equation
Default handler: &rbrace;
          \ignorespacesafterend
Default handler: &rbrace;
        </code>
        .
      </para>
    </section>
    <node name="xspace-package" spaces=" ">
      <nodename>
        xspace package
      </nodename>
      <nodenext automatic="on">
        Class and package commands
      </nodenext>
      <nodeprev automatic="on">
        \ignorespaces
        &
         \ignorespacesafterend
      </nodeprev>
      <nodeup automatic="on">
        Definitions
      </nodeup>
    </node>
    <section spaces=" ">
      <sectiontitle>
        <code>
          xspace
        </code>
         package
      </sectiontitle>
      <findex index="fn" spaces=" ">
        <indexterm index="fn" number="509" mergedindex="cp">
          \xspace
        </indexterm>
      </findex>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="555">
          <r>
            package
          </r>
          ,
          <code>
            xspace
          </code>
        </indexterm>
      </cindex>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="556">
          <code>
            xspace
          </code>
          <r>
            package
          </r>
        </indexterm>
      </cindex>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="557">
          spaces, ignore around commands
        </indexterm>
      </cindex>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="558">
          commands, ignore spaces
        </indexterm>
      </cindex>
      <para>
        This is an add-on package, not part of core
Default handler: &latex;
        . Synopsis:
      </para>
      <example endspaces=" ">
        <pre xml:space="preserve">
          \usepackage
Default handler: &lbrace;
          xspace
Default handler: &rbrace;
           ... \newcommand
Default handler: &lbrace;
          ...
Default handler: &rbrace;
Default handler: &lbrace;
          ...\xspace
Default handler: &rbrace;
        </pre>
      </example>
      <para>
        The
        <code>
          \xspace
        </code>
         macro, when used at the end of a command definition, adds a space unless the command is followed by certain punctuation characters.
      </para>
      <para>
        After a control sequence that is a control word (
        <pxref label="Control-sequences">
          <xrefnodename>
            Control sequences
          </xrefnodename>
        </pxref>
        , as opposed to control symbols such as
        <code>
          \$
        </code>
        ),
Default handler: &tex;
         gobbles blank characters. Thus, in the first sentence below, the output has
        <samp>
          Vermont
        </samp>
         placed snugly against the period, without any intervening space, despite the space in the input.
      </para>
      <example endspaces=" ">
        <pre xml:space="preserve">
          \newcommand
Default handler: &lbrace;
          \VT
Default handler: &rbrace;
Default handler: &lbrace;
          Vermont
Default handler: &rbrace;
           Our college is in \VT . \VT
Default handler: &lbrace;
Default handler: &rbrace;
           summers are nice.
        </pre>
      </example>
      <para>
        But because of the gobbling, the second sentence needs the empty curly braces or else there would be no space separating
        <samp>
          Vermont
        </samp>
         from
        <samp>
          summers
        </samp>
        . (Many authors instead use a backslash-space
        <code>
          \
        </code>
         for this.
        <xref label="_005c_0028SPACE_0029">
          <xrefnodename>
            \(SPACE)
          </xrefnodename>
        </xref>
        .)
      </para>
      <para>
        The
        <code>
          xspace
        </code>
         package provides
        <code>
          \xspace
        </code>
        . It is for writing commands which are designed to be used mainly in text. It must be placed at the very end of the definition of these commands. It inserts a space after that command unless what immediately follows is in a list of exceptions. In this example, the empty braces are not needed.
      </para>
      <example endspaces=" ">
        <pre xml:space="preserve">
          \newcommand
Default handler: &lbrace;
          \VT
Default handler: &rbrace;
Default handler: &lbrace;
          Vermont\xspace
Default handler: &rbrace;
           Our college is in \VT . \VT summers are nice.
        </pre>
      </example>
      <para>
        The default exception list contains the characters
        <code>
          ,.'/?;:!~-)
        </code>
        , the open curly brace and the backslash-space command discussed above, and the commands
        <code>
          \footnote
        </code>
         or
        <code>
          \footnotemark
        </code>
        . You can add to that list as with
        <code>
          \xspaceaddexceptions
Default handler: &lbrace;
          \myfni \myfnii
Default handler: &rbrace;
        </code>
         which adds
        <code>
          \myfni
        </code>
         and
Default handler: &nbsp;
        <code>
          \myfnii
        </code>
         to the list; and you can remove from that list as with
        <code>
          \xspaceremoveexception
Default handler: &lbrace;
          !
Default handler: &rbrace;
        </code>
        .
      </para>
Default handler: <!-- c David Carlisle https://tex.stackexchange.com/a/86620/339 -->
      <para>
        A comment: many experts prefer not to use
        <code>
          \xspace
        </code>
        . Putting it in a definition means that the command will usually get the spacing right. But it isn
Default handler: &textrsquo;
        t easy to predict when to enter empty braces because
        <code>
          \xspace
        </code>
         will get it wrong, such as when it is followed by another command, and so
        <code>
          \xspace
        </code>
         can make editing material harder and more error-prone than instead of always inserting the empty braces.
      </para>
    </section>
    <node name="Class-and-package-commands" spaces=" ">
      <nodename>
        Class and package commands
      </nodename>
      <nodeprev automatic="on">
        xspace package
      </nodeprev>
      <nodeup automatic="on">
        Definitions
      </nodeup>
    </node>
    <section spaces=" ">
      <sectiontitle>
        Class and package commands
      </sectiontitle>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="559">
          class and package commands
        </indexterm>
      </cindex>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="560">
          package and class commands
        </indexterm>
      </cindex>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="561">
          commands, class and package
        </indexterm>
      </cindex>
      <para>
        These are commands designed to help writers of classes or packages.
      </para>
      <menu endspaces=" ">
        <menuentry>
          <menuleadingtext>
            *
          </menuleadingtext>
          <menunode>
            \AtBeginDvi
            &
             \AtEndDvi
          </menunode>
          <menuseparator>
            ::
          </menuseparator>
          <menudescription>
            <pre xml:space="preserve"/>
          </menudescription>
        </menuentry>
        <menuentry>
          <menuleadingtext>
            *
          </menuleadingtext>
          <menunode>
            \AtEndOfClass
            &
             \AtEndOfPackage
          </menunode>
          <menuseparator>
            ::
          </menuseparator>
          <menudescription>
            <pre xml:space="preserve"/>
          </menudescription>
        </menuentry>
        <menuentry>
          <menuleadingtext>
            *
          </menuleadingtext>
          <menunode>
            \CheckCommand
          </menunode>
          <menuseparator>
            ::
          </menuseparator>
          <menudescription>
            <pre xml:space="preserve"/>
          </menudescription>
        </menuentry>
        <menuentry>
          <menuleadingtext>
            *
          </menuleadingtext>
          <menunode>
            \ClassError and \PackageError and others
          </menunode>
          <menuseparator>
            ::
          </menuseparator>
          <menudescription>
            <pre xml:space="preserve"/>
          </menudescription>
        </menuentry>
        <menuentry>
          <menuleadingtext>
            *
          </menuleadingtext>
          <menunode>
            \CurrentOption
          </menunode>
          <menuseparator>
            ::
          </menuseparator>
          <menudescription>
            <pre xml:space="preserve"/>
          </menudescription>
        </menuentry>
        <menuentry>
          <menuleadingtext>
            *
          </menuleadingtext>
          <menunode>
            \DeclareOption
          </menunode>
          <menuseparator>
            ::
          </menuseparator>
          <menudescription>
            <pre xml:space="preserve"/>
          </menudescription>
        </menuentry>
        <menuentry>
          <menuleadingtext>
            *
          </menuleadingtext>
          <menunode>
            \DeclareRobustCommand
          </menunode>
          <menuseparator>
            ::
          </menuseparator>
          <menudescription>
            <pre xml:space="preserve"/>
          </menudescription>
        </menuentry>
        <menuentry>
          <menuleadingtext>
            *
          </menuleadingtext>
          <menunode>
            \ExecuteOptions
          </menunode>
          <menuseparator>
            ::
          </menuseparator>
          <menudescription>
            <pre xml:space="preserve"/>
          </menudescription>
        </menuentry>
        <menuentry>
          <menuleadingtext>
            *
          </menuleadingtext>
          <menunode>
            \IfFileExists
            &
             \InputIfFileExists
          </menunode>
          <menuseparator>
            ::
          </menuseparator>
          <menudescription>
            <pre xml:space="preserve"/>
          </menudescription>
        </menuentry>
        <menuentry>
          <menuleadingtext>
            *
          </menuleadingtext>
          <menunode>
            \LoadClass
            &
             \LoadClassWithOptions
          </menunode>
          <menuseparator>
            ::
          </menuseparator>
          <menudescription>
            <pre xml:space="preserve"/>
          </menudescription>
        </menuentry>
        <menuentry>
          <menuleadingtext>
            *
          </menuleadingtext>
          <menunode>
            \NeedsTeXFormat
          </menunode>
          <menuseparator>
            ::
          </menuseparator>
          <menudescription>
            <pre xml:space="preserve"/>
          </menudescription>
        </menuentry>
        <menuentry>
          <menuleadingtext>
            *
          </menuleadingtext>
          <menunode>
            \OptionNotUsed
          </menunode>
          <menuseparator>
            ::
          </menuseparator>
          <menudescription>
            <pre xml:space="preserve"/>
          </menudescription>
        </menuentry>
        <menuentry>
          <menuleadingtext>
            *
          </menuleadingtext>
          <menunode>
            \PassOptionsToClass
            &
             \PassOptionsToPackage
          </menunode>
          <menuseparator>
            ::
          </menuseparator>
          <menudescription>
            <pre xml:space="preserve"/>
          </menudescription>
        </menuentry>
        <menuentry>
          <menuleadingtext>
            *
          </menuleadingtext>
          <menunode>
            \ProcessOptions
          </menunode>
          <menuseparator>
            ::
          </menuseparator>
          <menudescription>
            <pre xml:space="preserve"/>
          </menudescription>
        </menuentry>
        <menuentry>
          <menuleadingtext>
            *
          </menuleadingtext>
          <menunode>
            \ProvidesClass
            &
             \ProvidesPackage
          </menunode>
          <menuseparator>
            ::
          </menuseparator>
          <menudescription>
            <pre xml:space="preserve"/>
          </menudescription>
        </menuentry>
        <menuentry>
          <menuleadingtext>
            *
          </menuleadingtext>
          <menunode>
            \ProvidesFile
          </menunode>
          <menuseparator>
            ::
          </menuseparator>
          <menudescription>
            <pre xml:space="preserve"/>
          </menudescription>
        </menuentry>
        <menuentry>
          <menuleadingtext>
            *
          </menuleadingtext>
          <menunode>
            \RequirePackage
            &
             \RequirePackageWithOptions
          </menunode>
          <menuseparator>
            ::
          </menuseparator>
          <menudescription>
            <pre xml:space="preserve"/>
          </menudescription>
        </menuentry>
      </menu>
      <node name="_005cAtBeginDvi-_0026-_005cAtEndDvi" spaces=" ">
        <nodename>
          \AtBeginDvi
          &
           \AtEndDvi
        </nodename>
        <nodenext automatic="on">
          \AtEndOfClass
          &
           \AtEndOfPackage
        </nodenext>
        <nodeup automatic="on">
          Class and package commands
        </nodeup>
      </node>
      <subsection spaces=" ">
        <sectiontitle>
          <code>
            \AtBeginDvi
          </code>
          &
          <code>
            \AtEndDvi
          </code>
        </sectiontitle>
        <anchor name="_005cAtBeginDvi">
          \AtBeginDvi
        </anchor>
        <anchor name="_005cAtEndDvi">
          \AtEndDvi
        </anchor>
        <findex index="fn" spaces=" ">
          <indexterm index="fn" number="510" mergedindex="cp">
            \AtBeginDvi
          </indexterm>
        </findex>
        <findex index="fn" spaces=" ">
          <indexterm index="fn" number="511" mergedindex="cp">
            \AtEndDvi
          </indexterm>
        </findex>
        <para>
          Synopsis:
        </para>
        <example endspaces=" ">
          <pre xml:space="preserve">
            \AtBeginDvi
Default handler: &lbrace;
            <var>
              code
            </var>
Default handler: &rbrace;
             \AtEndDvi
Default handler: &lbrace;
            <var>
              code
            </var>
Default handler: &rbrace;
          </pre>
        </example>
        <para>
          <code>
            \AtBeginDvi
          </code>
           saves, in a box register,
          <var>
            code
          </var>
           to be executed at the beginning of the shipout of the first page of the document. Despite the name, it applies to DVI, PDF, and XDV output. It fills the
          <code>
            shipout/firstpage
          </code>
           hook; new code should use that hook directly.
        </para>
        <cindex index="cp" spaces=" ">
          <indexterm index="cp" number="562">
            <r>
              package
            </r>
            ,
            <code>
              atenddvi
            </code>
          </indexterm>
        </cindex>
        <cindex index="cp" spaces=" ">
          <indexterm index="cp" number="563">
            <code>
              atenddvi
            </code>
            <r>
              package
            </r>
          </indexterm>
        </cindex>
        <para>
          Similarly,
          <code>
            \AtEndDvi
          </code>
           (previously available only with the
          <code>
            atenddvi
          </code>
           package) is code executed when finalizing the main output document.
        </para>
      </subsection>
      <node name="_005cAtEndOfClass-_0026-_005cAtEndOfPackage" spaces=" ">
        <nodename>
          \AtEndOfClass
          &
           \AtEndOfPackage
        </nodename>
        <nodenext automatic="on">
          \CheckCommand
        </nodenext>
        <nodeprev automatic="on">
          \AtBeginDvi
          &
           \AtEndDvi
        </nodeprev>
        <nodeup automatic="on">
          Class and package commands
        </nodeup>
      </node>
      <subsection spaces=" ">
        <sectiontitle>
          <code>
            \AtEndOfClass
          </code>
          &
          <code>
            \AtEndOfPackage
          </code>
        </sectiontitle>
        <anchor name="_005cAtEndOfClass">
          \AtEndOfClass
        </anchor>
        <anchor name="_005cAtEndOfPackage">
          \AtEndOfPackage
        </anchor>
        <findex index="fn" spaces=" ">
          <indexterm index="fn" number="512" mergedindex="cp">
            \AtEndOfClass
          </indexterm>
        </findex>
        <findex index="fn" spaces=" ">
          <indexterm index="fn" number="513" mergedindex="cp">
            \AtEndOfPackage
          </indexterm>
        </findex>
        <para>
          Synopses:
        </para>
        <example endspaces=" ">
          <pre xml:space="preserve">
            \AtEndOfClass
Default handler: &lbrace;
            <var>
              code
            </var>
Default handler: &rbrace;
             \AtEndOfPackage
Default handler: &lbrace;
            <var>
              code
            </var>
Default handler: &rbrace;
          </pre>
        </example>
        <para>
          Hooks to insert
          <var>
            code
          </var>
           to be executed when
Default handler: &latex;
           finishes processing the current class resp.
Default handler: &noeos;
           package.
        </para>
        <para>
          These hooks can be used multiple times; each
          <code>
            code
          </code>
           segment will be executed in the order called. Many packages and classes use these commands.
        </para>
        <para>
          See also
          <ref label="_005cAtBeginDocument">
            <xrefnodename>
              \AtBeginDocument
            </xrefnodename>
          </ref>
          .
        </para>
      </subsection>
      <node name="_005cCheckCommand" spaces=" ">
        <nodename>
          \CheckCommand
        </nodename>
        <nodenext automatic="on">
          \ClassError and \PackageError and others
        </nodenext>
        <nodeprev automatic="on">
          \AtEndOfClass
          &
           \AtEndOfPackage
        </nodeprev>
        <nodeup automatic="on">
          Class and package commands
        </nodeup>
      </node>
      <subsection spaces=" ">
        <sectiontitle>
          <code>
            \CheckCommand
          </code>
        </sectiontitle>
        <findex index="fn" spaces=" ">
          <indexterm index="fn" number="514" mergedindex="cp">
            \CheckCommand
          </indexterm>
        </findex>
        <cindex index="cp" spaces=" ">
          <indexterm index="cp" number="564">
            new command, checking definition of
          </indexterm>
        </cindex>
        <cindex index="cp" spaces=" ">
          <indexterm index="cp" number="565">
            long command
          </indexterm>
        </cindex>
        <cindex index="cp" spaces=" ">
          <indexterm index="cp" number="566">
            <code>
              \long
            </code>
             command, checking for
          </indexterm>
        </cindex>
        <para>
          Synopsis:
        </para>
        <example endspaces=" ">
          <pre xml:space="preserve">
            \CheckCommand
Default handler: &lbrace;
            <var>
              cmd
            </var>
Default handler: &rbrace;
            [
            <var>
              num
            </var>
            ][
            <var>
              default
            </var>
            ]
Default handler: &lbrace;
            <var>
              definition
            </var>
Default handler: &rbrace;
             \CheckCommand*
            <r>
              (same parameters)
            </r>
          </pre>
        </example>
        <para>
          Like
          <code>
            \newcommand
          </code>
           (
          <pxref label="_005cnewcommand-_0026-_005crenewcommand">
            <xrefnodename>
              \newcommand
              &
               \renewcommand
            </xrefnodename>
          </pxref>
          ) but does not define
          <var>
            cmd
          </var>
          ; instead it checks that the current definition of
          <var>
            cmd
          </var>
           is exactly as given by
          <var>
            definition
          </var>
           and is or is not
          <dfn>
            <code>
              \long
            </code>
          </dfn>
           as expected. A long command is a command that accepts
          <code>
            \par
          </code>
           within an argument.
        </para>
        <para>
          With the unstarred version of
          <code>
            \CheckCommand
          </code>
          ,
          <var>
            cmd
          </var>
           is expected to be
          <code>
            \long
          </code>
          ; with the starred version,
          <var>
            cmd
          </var>
           must not be
          <code>
            \long
          </code>
        </para>
        <para>
          <code>
            \CheckCommand
          </code>
           raises an error when the check fails. This allows you to check before you start redefining
          <code>
            cmd
          </code>
           yourself that no other package has already redefined this command.
        </para>
      </subsection>
      <node name="_005cClassError-and-_005cPackageError-and-others" spaces=" ">
        <nodename>
          \ClassError and \PackageError and others
        </nodename>
        <nodenext automatic="on">
          \CurrentOption
        </nodenext>
        <nodeprev automatic="on">
          \CheckCommand
        </nodeprev>
        <nodeup automatic="on">
          Class and package commands
        </nodeup>
      </node>
      <subsection spaces=" ">
        <sectiontitle>
          <code>
            \ClassError
          </code>
           and
          <code>
            \PackageError
          </code>
           and others
        </sectiontitle>
        <anchor name="_005cClassError">
          \ClassError
        </anchor>
        <anchor name="_005cClassWarning">
          \ClassWarning
        </anchor>
        <anchor name="_005cClassWarningNoLine">
          \ClassWarningNoLine
        </anchor>
        <anchor name="_005cClassInfo">
          \ClassInfo
        </anchor>
        <anchor name="_005cClassInfoNoLine">
          \ClassInfoNoLine
        </anchor>
        <anchor name="_005cPackageError">
          \PackageError
        </anchor>
        <anchor name="_005cPackageWarning">
          \PackageWarning
        </anchor>
        <anchor name="_005cPackageWarningNoLine">
          \PackageWarningNoLine
        </anchor>
        <anchor name="_005cPackageInfo">
          \PackageInfo
        </anchor>
        <anchor name="_005cPackageInfoNoLine">
          \PackageInfoNoLine
        </anchor>
        <para>
          Produce error, warning, and informational messages for classes:
        </para>
        <table commandarg="code" spaces=" " endspaces=" ">
          <tableentry>
            <tableterm>
              <item spaces=" ">
                <itemformat command="code">
                  \ClassError
Default handler: &lbrace;
                  <var>
                    class name
                  </var>
Default handler: &rbrace;
Default handler: &lbrace;
                  <var>
                    error-text
                  </var>
Default handler: &rbrace;
Default handler: &lbrace;
                  <var>
                    help-text
                  </var>
Default handler: &rbrace;
                </itemformat>
              </item>
              <itemx spaces=" ">
                <itemformat command="code">
                  \ClassWarning
Default handler: &lbrace;
                  <var>
                    class name
                  </var>
Default handler: &rbrace;
Default handler: &lbrace;
                  <var>
                    warning-text
                  </var>
Default handler: &rbrace;
                </itemformat>
              </itemx>
              <itemx spaces=" ">
                <itemformat command="code">
                  \ClassWarningNoLine
Default handler: &lbrace;
                  <var>
                    class name
                  </var>
Default handler: &rbrace;
Default handler: &lbrace;
                  <var>
                    warning-text
                  </var>
Default handler: &rbrace;
                </itemformat>
              </itemx>
              <itemx spaces=" ">
                <itemformat command="code">
                  \ClassInfo
Default handler: &lbrace;
                  <var>
                    class name
                  </var>
Default handler: &rbrace;
Default handler: &lbrace;
                  <var>
                    info-text
                  </var>
Default handler: &rbrace;
                </itemformat>
              </itemx>
              <itemx spaces=" ">
                <itemformat command="code">
                  \ClassInfoNoLine
Default handler: &lbrace;
                  <var>
                    class name
                  </var>
Default handler: &rbrace;
Default handler: &lbrace;
                  <var>
                    info-text
                  </var>
Default handler: &rbrace;
                </itemformat>
              </itemx>
            </tableterm>
            <tableitem>
              <findex index="fn" spaces=" ">
                <indexterm index="fn" number="515" mergedindex="cp">
                  \ClassError
                </indexterm>
              </findex>
              <findex index="fn" spaces=" ">
                <indexterm index="fn" number="516" mergedindex="cp">
                  \ClassWarning
                </indexterm>
              </findex>
              <findex index="fn" spaces=" ">
                <indexterm index="fn" number="517" mergedindex="cp">
                  \ClassWarningNoLine
                </indexterm>
              </findex>
              <findex index="fn" spaces=" ">
                <indexterm index="fn" number="518" mergedindex="cp">
                  \ClassInfo
                </indexterm>
              </findex>
              <findex index="fn" spaces=" ">
                <indexterm index="fn" number="519" mergedindex="cp">
                  \ClassInfoNoLine
                </indexterm>
              </findex>
            </tableitem>
          </tableentry>
        </table>
        <noindent/>
        <para>
          and the same for packages:
        </para>
        <table commandarg="code" spaces=" " endspaces=" ">
          <tableentry>
            <tableterm>
              <item spaces=" ">
                <itemformat command="code">
                  \PackageError
Default handler: &lbrace;
                  <var>
                    package name
                  </var>
Default handler: &rbrace;
Default handler: &lbrace;
                  <var>
                    error-text
                  </var>
Default handler: &rbrace;
Default handler: &lbrace;
                  <var>
                    help-text
                  </var>
Default handler: &rbrace;
                </itemformat>
              </item>
              <itemx spaces=" ">
                <itemformat command="code">
                  \PackageWarning
Default handler: &lbrace;
                  <var>
                    package name
                  </var>
Default handler: &rbrace;
Default handler: &lbrace;
                  <var>
                    warning-text
                  </var>
Default handler: &rbrace;
                </itemformat>
              </itemx>
              <itemx spaces=" ">
                <itemformat command="code">
                  \PackageWarningNoLine
Default handler: &lbrace;
                  <var>
                    package name
                  </var>
Default handler: &rbrace;
Default handler: &lbrace;
                  <var>
                    warning-text
                  </var>
Default handler: &rbrace;
                </itemformat>
              </itemx>
              <itemx spaces=" ">
                <itemformat command="code">
                  \PackageInfo
Default handler: &lbrace;
                  <var>
                    package name
                  </var>
Default handler: &rbrace;
Default handler: &lbrace;
                  <var>
                    info-text
                  </var>
Default handler: &rbrace;
                </itemformat>
              </itemx>
              <itemx spaces=" ">
                <itemformat command="code">
                  \PackageInfoNoLine
Default handler: &lbrace;
                  <var>
                    package name
                  </var>
Default handler: &rbrace;
Default handler: &lbrace;
                  <var>
                    info-text
                  </var>
Default handler: &rbrace;
                </itemformat>
              </itemx>
            </tableterm>
            <tableitem>
              <findex index="fn" spaces=" ">
                <indexterm index="fn" number="520" mergedindex="cp">
                  \PackageError
                </indexterm>
              </findex>
              <findex index="fn" spaces=" ">
                <indexterm index="fn" number="521" mergedindex="cp">
                  \PackageWarning
                </indexterm>
              </findex>
              <findex index="fn" spaces=" ">
                <indexterm index="fn" number="522" mergedindex="cp">
                  \PackageWarningNoLine
                </indexterm>
              </findex>
              <findex index="fn" spaces=" ">
                <indexterm index="fn" number="523" mergedindex="cp">
                  \PackageInfo
                </indexterm>
              </findex>
              <findex index="fn" spaces=" ">
                <indexterm index="fn" number="524" mergedindex="cp">
                  \PackageInfoNoLine
                </indexterm>
              </findex>
            </tableitem>
          </tableentry>
        </table>
        <para>
          For
          <code>
            \ClassError
          </code>
           and
          <code>
            \PackageError
          </code>
           the message is
          <var>
            error-text
          </var>
          , followed by
Default handler: &tex;
Default handler: &textrsquo;
          s
Default handler: &textlsquo;
          <code>
            ?
          </code>
Default handler: &textrsquo;
           error prompt. If the user then asks for help by typing
          <code>
            h
          </code>
          , they see the
          <var>
            help text
          </var>
          .
        </para>
        <para>
          The four
          <code>
            Warning
          </code>
           commands are similar except that they write
          <var>
            warning-text
          </var>
           on the screen with no error prompt. The four
          <code>
            Info
          </code>
           commands write
          <var>
            info-text
          </var>
           only in the transcript file. The
          <code>
            NoLine
          </code>
           versions omit the number of the line generating the message, while the other versions do show that number.
        </para>
        <cindex index="cp" spaces=" ">
          <indexterm index="cp" number="567">
            <code>
              \protect
            </code>
            , and message text
          </indexterm>
        </cindex>
        <cindex index="cp" spaces=" ">
          <indexterm index="cp" number="568">
            <code>
              \space
            </code>
            , and message text
          </indexterm>
        </cindex>
        <cindex index="cp" spaces=" ">
          <indexterm index="cp" number="569">
            <code>
              \MessageBreak
            </code>
            , and message text
          </indexterm>
        </cindex>
        <para>
          To format the messages, including the
          <var>
            help-text
          </var>
          : use
          <code>
            \protect
          </code>
           to stop a command from expanding, get a line break with
          <code>
            \MessageBreak
          </code>
          , and get a space with
          <code>
            \space
          </code>
           when a space character is ignore, most commonly after a command.
        </para>
        <paraDefault handler: &latex;
>
           appends a period to the messages.
        </para>
      </subsection>
      <node name="_005cCurrentOption" spaces=" ">
        <nodename>
          \CurrentOption
        </nodename>
        <nodenext automatic="on">
          \DeclareOption
        </nodenext>
        <nodeprev automatic="on">
          \ClassError and \PackageError and others
        </nodeprev>
        <nodeup automatic="on">
          Class and package commands
        </nodeup>
      </node>
      <subsection spaces=" ">
        <sectiontitle>
          <code>
            \CurrentOption
          </code>
        </sectiontitle>
        <findex index="fn" spaces=" ">
          <indexterm index="fn" number="525" mergedindex="cp">
            \CurrentOption
          </indexterm>
        </findex>
        <cindex index="cp" spaces=" ">
          <indexterm index="cp" number="570">
            option, currently being processed
          </indexterm>
        </cindex>
        <para>
          Expands to the name of the option currently being processed. This can only be used within the
          <var>
            code
          </var>
           argument of either
          <code>
            \DeclareOption
          </code>
           or
          <code>
            \DeclareOption*
          </code>
          .
        </para>
      </subsection>
      <node name="_005cDeclareOption" spaces=" ">
        <nodename>
          \DeclareOption
        </nodename>
        <nodenext automatic="on">
          \DeclareRobustCommand
        </nodenext>
        <nodeprev automatic="on">
          \CurrentOption
        </nodeprev>
        <nodeup automatic="on">
          Class and package commands
        </nodeup>
      </node>
      <subsection spaces=" ">
        <sectiontitle>
          <code>
            \DeclareOption
          </code>
        </sectiontitle>
        <findex index="fn" spaces=" ">
          <indexterm index="fn" number="526" mergedindex="cp">
            \DeclareOption
          </indexterm>
        </findex>
        <cindex index="cp" spaces=" ">
          <indexterm index="cp" number="571">
            class options
          </indexterm>
        </cindex>
        <cindex index="cp" spaces=" ">
          <indexterm index="cp" number="572">
            package options
          </indexterm>
        </cindex>
        <cindex index="cp" spaces=" ">
          <indexterm index="cp" number="573">
            options, class
          </indexterm>
        </cindex>
        <cindex index="cp" spaces=" ">
          <indexterm index="cp" number="574">
            options, package
          </indexterm>
        </cindex>
        <para>
          Synopsis:
        </para>
        <example endspaces=" ">
          <pre xml:space="preserve">
            \DeclareOption
Default handler: &lbrace;
            <var>
              option
            </var>
Default handler: &rbrace;
Default handler: &lbrace;
            <var>
              code
            </var>
Default handler: &rbrace;
             \DeclareOption*
Default handler: &lbrace;
            <var>
              option
            </var>
Default handler: &rbrace;
Default handler: &lbrace;
            <var>
              code
            </var>
Default handler: &rbrace;
          </pre>
        </example>
        <para>
          Define an option a user can include in their
          <code>
            \documentclass
          </code>
           command. For example, a class
          <code>
            smcmemo
          </code>
           could have an option
          <code>
            logo
          </code>
           allowing users to put the institutional logo on the first page. The document would start with
          <code>
            \documentclass[logo]
Default handler: &lbrace;
            smcmemo
Default handler: &rbrace;
          </code>
          . To enable this, the class file must contain
          <code>
            \DeclareOption
Default handler: &lbrace;
            logo
Default handler: &rbrace;
Default handler: &lbrace;
            <var>
              code
            </var>
Default handler: &rbrace;
          </code>
           (and later,
          <code>
            \ProcessOptions
          </code>
          ).
        </para>
        <cindex index="cp" spaces=" ">
          <indexterm index="cp" number="575">
            default option processing
          </indexterm>
        </cindex>
        <cindex index="cp" spaces=" ">
          <indexterm index="cp" number="576">
            option processing by default
          </indexterm>
        </cindex>
        <cindex index="cp" spaces=" ">
          <indexterm index="cp" number="577">
            <code>
              Unused global option
            </code>
             warning, handling
          </indexterm>
        </cindex>
        <para>
          If you request an option that has not been declared, by default this will produce a warning like
          <code>
            Unused global option(s): [badoption].
          </code>
           This can be changed by using
          <code>
            \DeclareOption*
Default handler: &lbrace;
            <var>
              code
            </var>
Default handler: &rbrace;
          </code>
          , which executes
          <var>
            code
          </var>
           for any unknown option.
        </para>
        <para>
          For example, many classes extend an existing class, using code such as
          <code>
            \LoadClass
Default handler: &lbrace;
            article
Default handler: &rbrace;
          </code>
           (
          <pxref label="_005cLoadClass">
            <xrefnodename>
              \LoadClass
            </xrefnodename>
          </pxref>
          ). In this case, it makes sense to pass any otherwise-unknown options to the underlying class, like this:
        </para>
        <example endspaces=" ">
          <pre xml:space="preserve">
            \DeclareOption*
Default handler: &lbrace;
            % \PassOptionsToClass
Default handler: &lbrace;
            \CurrentOption
Default handler: &rbrace;
Default handler: &lbrace;
            article
Default handler: &rbrace;
            %
Default handler: &rbrace;
          </pre>
        </example>
        <para>
          As another example, our class
          <code>
            smcmemo
          </code>
           might allow users to keep lists of memo recipients in external files, so the user could invoke
          <code>
            \documentclass[math]
Default handler: &lbrace;
            smcmemo
Default handler: &rbrace;
          </code>
           and it will read the file
          <code>
            math.memo
          </code>
          . This code inputs the file if it exists, while if it doesn
Default handler: &textrsquo;
          t, the option is passed to the
          <code>
            article
          </code>
           class:
        </para>
        <example endspaces=" ">
          <pre xml:space="preserve">
            \DeclareOption*
Default handler: &lbrace;
            \InputIfFileExists
Default handler: &lbrace;
            \CurrentOption.memo
Default handler: &rbrace;
Default handler: &lbrace;
Default handler: &rbrace;
Default handler: &lbrace;
            % \PassOptionsToClass
Default handler: &lbrace;
            \CurrentOption
Default handler: &rbrace;
Default handler: &lbrace;
            article
Default handler: &rbrace;
Default handler: &rbrace;
Default handler: &rbrace;
          </pre>
        </example>
      </subsection>
      <node name="_005cDeclareRobustCommand" spaces=" ">
        <nodename>
          \DeclareRobustCommand
        </nodename>
        <nodenext automatic="on">
          \ExecuteOptions
        </nodenext>
        <nodeprev automatic="on">
          \DeclareOption
        </nodeprev>
        <nodeup automatic="on">
          Class and package commands
        </nodeup>
      </node>
      <subsection spaces=" ">
        <sectiontitle>
          <code>
            \DeclareRobustCommand
          </code>
        </sectiontitle>
        <findex index="fn" spaces=" ">
          <indexterm index="fn" number="527" mergedindex="cp">
            \DeclareRobustCommand
          </indexterm>
        </findex>
        <cindex index="cp" spaces=" ">
          <indexterm index="cp" number="578">
            new command, definition
          </indexterm>
        </cindex>
        <cindex index="cp" spaces=" ">
          <indexterm index="cp" number="579">
            robust command, defining
          </indexterm>
        </cindex>
        <para>
          Synopsis:
        </para>
        <example endspaces=" ">
          <pre xml:space="preserve">
            \DeclareRobustCommand
Default handler: &lbrace;
            <var>
              cmd
            </var>
Default handler: &rbrace;
            [
            <var>
              num
            </var>
            ][
            <var>
              default
            </var>
            ]
Default handler: &slashbreak;
Default handler: &lbrace;
            <var>
              definition
            </var>
Default handler: &rbrace;
             \DeclareRobustCommand*
            <r>
              (same parameters
            </r>
          </pre>
        </example>
        <para>
          <code>
            \DeclareRobustCommand
          </code>
           and its starred form are generally like
          <code>
            \newcommand
          </code>
           and
          <code>
            \newcommand*
          </code>
           (
          <pxref label="_005cnewcommand-_0026-_005crenewcommand">
            <xrefnodename>
              \newcommand
              &
               \renewcommand
            </xrefnodename>
          </pxref>
          ), with the addition that they define a so-called
          <dfn>
            robust
          </dfn>
           command, even if some code within the
          <var>
            definition
          </var>
           is fragile. (For a discussion of robust and fragile commands,
          <pxref label="_005cprotect">
            <xrefnodename>
              \protect
            </xrefnodename>
          </pxref>
          .)
        </para>
        <para>
          Also unlike
          <code>
            \newcommand
          </code>
          , these do not give an error if macro
          <var>
            cmd
          </var>
           already exists; instead, a log message is put into the transcript file if a command is redefined. Thus,
          <code>
            \DeclareRobustCommand
          </code>
           can be used to define new robust commands or to redefine existing commands, making them robust.
        </para>
        <para>
          The starred form,
          <code>
            \DeclareRobustCommand*
          </code>
          , disallows the arguments from containing multiple paragraphs, just like the starred form of
          <code>
            \newcommand
          </code>
           and
          <code>
            \renewcommand
          </code>
          . The meaning of the arguments is the same.
        </para>
        <para>
          Commands defined this way are a bit less efficient than those defined using
          <code>
            \newcommand
          </code>
           so unless the command
Default handler: &textrsquo;
          s data is fragile and the command is used within a moving argument, use
          <code>
            \newcommand
          </code>
          .
        </para>
        <cindex index="cp" spaces=" ">
          <indexterm index="cp" number="580">
            <r>
              package
            </r>
            ,
            <code>
              etoolbox
            </code>
          </indexterm>
        </cindex>
        <cindex index="cp" spaces=" ">
          <indexterm index="cp" number="581">
            <code>
              etoolbox
            </code>
            <r>
              package
            </r>
          </indexterm>
        </cindex>
        <cindex index="cp" spaces=" ">
          <indexterm index="cp" number="582">
            e-
Default handler: &tex;
            , and robust commands
          </indexterm>
        </cindex>
        <findex index="fn" spaces=" ">
          <indexterm index="fn" number="528" mergedindex="cp">
            \newrobustcmd
            <r>
              (
              <t>
                etoolbox
              </t>
               package)
            </r>
          </indexterm>
        </findex>
        <findex index="fn" spaces=" ">
          <indexterm index="fn" number="529" mergedindex="cp">
            \renewrobustcmd
            <r>
              (
              <t>
                etoolbox
              </t>
               package)
            </r>
          </indexterm>
        </findex>
        <findex index="fn" spaces=" ">
          <indexterm index="fn" number="530" mergedindex="cp">
            \providerobustcmd
            <r>
              (
              <t>
                etoolbox
              </t>
               package)
            </r>
          </indexterm>
        </findex>
        <para>
          Related to this, the
          <code>
            etoolbox
          </code>
           package offers three commands and their starred forms:
          <code>
            \newrobustcmd
          </code>
          (
          <code>
            *
          </code>
          )
          <code>
            \renewrobustcmd
          </code>
          (
          <code>
            *
          </code>
          ), and
          <code>
            \providerobustcmd
          </code>
          (
          <code>
            *
          </code>
          ). They are similar to
          <code>
            \newcommand
          </code>
          ,
          <code>
            \renewcommand
          </code>
          , and
          <code>
            \providecommand
          </code>
           and their own starred forms, but define a robust
          <var>
            cmd
          </var>
          . They have two possible advantages compared to
          <code>
            \DeclareRobustCommand
          </code>
          :
        </para>
        <enumerate first="1" endspaces=" ">
          <listitem>
            <para>
              They use the low-level e-
Default handler: &tex;
               protection mechanism rather than the higher-level
Default handler: &latex;
              <code>
                \protect
              </code>
               mechanism, so they do not incur the slight loss of performance mentioned above, and
            </para>
          </listitem>
          <listitem>
            <para>
              They make the same distinction between
              <code>
                \new
Default handler: &dots;
              </code>
              ,
              <code>
                \renew
Default handler: &dots;
              </code>
              , and
              <code>
                \provide
Default handler: &dots;
              </code>
              , as the standard commands. That is, they do not just write a log message when you redefine
              <var>
                cmd
              </var>
               that already exists; you need to use either
              <code>
                \renew
Default handler: &dots;
              </code>
               or
              <code>
                \provide
Default handler: &dots;
              </code>
              , or you get an error. This may or may not be a benefit.
            </para>
          </listitem>
        </enumerate>
      </subsection>
      <node name="_005cExecuteOptions" spaces=" ">
        <nodename>
          \ExecuteOptions
        </nodename>
        <nodenext automatic="on">
          \IfFileExists
          &
           \InputIfFileExists
        </nodenext>
        <nodeprev automatic="on">
          \DeclareRobustCommand
        </nodeprev>
        <nodeup automatic="on">
          Class and package commands
        </nodeup>
      </node>
      <subsection spaces=" ">
        <sectiontitle>
          <code>
            \ExecuteOptions
          </code>
        </sectiontitle>
        <findex index="fn" spaces=" ">
          <indexterm index="fn" number="531" mergedindex="cp">
            \ExecuteOptions
          </indexterm>
        </findex>
        <para>
          Synopsis:
        </para>
        <example endspaces=" ">
          <pre xml:space="preserve">
            \ExecuteOptions
Default handler: &lbrace;
            <var>
              option-list
            </var>
Default handler: &rbrace;
          </pre>
        </example>
        <findex index="fn" spaces=" ">
          <indexterm index="fn" number="532" mergedindex="cp">
            \ds
Default handler: &arobase;
            <var>
              option
            </var>
          </indexterm>
        </findex>
        <para>
          For each option
          <var>
            option
          </var>
           in
          <var>
            option-list
          </var>
          , in order, this command executes the command
          <code>
            \ds
Default handler: &arobase;
            <var>
              option
            </var>
          </code>
          . If this command is not defined then that option is silently ignored.
        </para>
        <para>
          This can be used to provide a default option list before
          <code>
            \ProcessOptions
          </code>
          . For example, if in a class file you want the default to be 11pt fonts then you could specify
          <code>
            \ExecuteOptions
Default handler: &lbrace;
            11pt
Default handler: &rbrace;
            \ProcessOptions\relax
          </code>
          .
        </para>
      </subsection>
      <node name="_005cIfFileExists-_0026-_005cInputIfFileExists" spaces=" ">
        <nodename>
          \IfFileExists
          &
           \InputIfFileExists
        </nodename>
        <nodenext automatic="on">
          \LoadClass
          &
           \LoadClassWithOptions
        </nodenext>
        <nodeprev automatic="on">
          \ExecuteOptions
        </nodeprev>
        <nodeup automatic="on">
          Class and package commands
        </nodeup>
      </node>
      <subsection spaces=" ">
        <sectiontitle>
          <code>
            \IfFileExists
          </code>
          &
          <code>
            \InputIfFileExists
          </code>
        </sectiontitle>
        <anchor name="_005cIfFileExists">
          \IfFileExists
        </anchor>
        <anchor name="_005cInputIfFileExists">
          \InputIfFileExists
        </anchor>
        <findex index="fn" spaces=" ">
          <indexterm index="fn" number="533" mergedindex="cp">
            \IfFileExists
          </indexterm>
        </findex>
        <findex index="fn" spaces=" ">
          <indexterm index="fn" number="534" mergedindex="cp">
            \InputIfFileExists
          </indexterm>
        </findex>
        <para>
          Synopses:
        </para>
        <example endspaces=" ">
          <pre xml:space="preserve">
            \IfFileExists
Default handler: &lbrace;
            <var>
              filename
            </var>
Default handler: &rbrace;
Default handler: &lbrace;
            <var>
              true-code
            </var>
Default handler: &rbrace;
Default handler: &lbrace;
            <var>
              false-code
            </var>
Default handler: &rbrace;
             \InputIfFileExists
Default handler: &lbrace;
            <var>
              filename
            </var>
Default handler: &rbrace;
Default handler: &lbrace;
            <var>
              true-code
            </var>
Default handler: &rbrace;
Default handler: &lbrace;
            <var>
              false-code
            </var>
Default handler: &rbrace;
          </pre>
        </example>
        <para>
          <code>
            \IfFileExists
          </code>
           executes
          <var>
            true-code
          </var>
           if
Default handler: &latex;
           finds the file
          <file>
            <var>
              filename
            </var>
          </file>
           or
          <var>
            false-code
          </var>
           otherwise. In the first case it executing
          <var>
            true-code
          </var>
           and then inputs the file. Thus the command
        </para>
        <example endspaces=" ">
          <pre xml:space="preserve">
            \IfFileExists
Default handler: &lbrace;
            img.pdf
Default handler: &rbrace;
Default handler: &lbrace;
            % \includegraphics
Default handler: &lbrace;
            img.pdf
Default handler: &rbrace;
Default handler: &rbrace;
Default handler: &lbrace;
            \typeout
Default handler: &lbrace;
            !! img.pdf not found
Default handler: &rbrace;
          </pre>
        </example>
        <noindent/>
        <para>
          will include the graphic
          <file>
            img.pdf
          </file>
           if it is found and otherwise give a warning.
        </para>
        <para>
          This command looks for the file in all search paths that
Default handler: &latex;
           uses, not only in the current directory. To look only in the current directory do something like
          <code>
            \IfFileExists
Default handler: &lbrace;
            ./
            <var>
              filename
            </var>
Default handler: &rbrace;
Default handler: &lbrace;
            <var>
              true-code
            </var>
Default handler: &rbrace;
Default handler: &lbrace;
            <var>
              false-code
            </var>
Default handler: &rbrace;
          </code>
          . If you ask for a filename without a
          <code>
            .tex
          </code>
           extension then
Default handler: &latex;
           will first look for the file by appending the
          <code>
            .tex
          </code>
          ; for more on how
Default handler: &latex;
           handles file extensions see
          <ref label="_005cinput">
            <xrefnodename>
              \input
            </xrefnodename>
          </ref>
          .
        </para>
        <para>
          <code>
            \InputIfFileExists
          </code>
           is similar, but, as the name states, automatically
          <code>
            \input
          </code>
          s
          <var>
            filename
          </var>
           if it exists. The
          <var>
            true-code
          </var>
           is executed just before the
          <code>
            \input
          </code>
          ; if the file doesn
Default handler: &textrsquo;
          t exist, the
          <var>
            false-code
          </var>
           is executed. An example:
        </para>
        <example endspaces=" ">
          <pre xml:space="preserve">
            \InputIfFileExists
Default handler: &lbrace;
            mypkg.cfg
Default handler: &rbrace;
Default handler: &lbrace;
            \PackageInfo
Default handler: &lbrace;
            Loading mypkg.cfg for configuration information
Default handler: &rbrace;
Default handler: &rbrace;
Default handler: &lbrace;
            \PackageInfo
Default handler: &lbrace;
            No mypkg.cfg found
Default handler: &rbrace;
Default handler: &rbrace;
          </pre>
        </example>
      </subsection>
      <node name="_005cLoadClass-_0026-_005cLoadClassWithOptions" spaces=" ">
        <nodename>
          \LoadClass
          &
           \LoadClassWithOptions
        </nodename>
        <nodenext automatic="on">
          \NeedsTeXFormat
        </nodenext>
        <nodeprev automatic="on">
          \IfFileExists
          &
           \InputIfFileExists
        </nodeprev>
        <nodeup automatic="on">
          Class and package commands
        </nodeup>
      </node>
      <subsection spaces=" ">
        <sectiontitle>
          <code>
            \LoadClass
          </code>
          &
          <code>
            \LoadClassWithOptions
          </code>
        </sectiontitle>
        <anchor name="_005cLoadClass">
          \LoadClass
        </anchor>
        <anchor name="_005cLoadClassWithOptions">
          \LoadClassWithOptions
        </anchor>
        <findex index="fn" spaces=" ">
          <indexterm index="fn" number="535" mergedindex="cp">
            \LoadClass
          </indexterm>
        </findex>
        <findex index="fn" spaces=" ">
          <indexterm index="fn" number="536" mergedindex="cp">
            \LoadClassWithOptions
          </indexterm>
        </findex>
        <para>
          Synopses:
        </para>
        <example endspaces=" ">
          <pre xml:space="preserve">
            \LoadClass[
            <var>
              options-list
            </var>
            ]
Default handler: &lbrace;
            <var>
              class-name
            </var>
Default handler: &rbrace;
            [
            <var>
              release-date
            </var>
            ] \LoadClassWithOptions
Default handler: &lbrace;
            <var>
              class-name
            </var>
Default handler: &rbrace;
            [
            <var>
              release-date
            </var>
            ]
          </pre>
        </example>
        <para>
          Load a class, as with
          <code>
            \documentclass[
            <var>
              options-list
            </var>
            ]
Default handler: &lbrace;
            <var>
              class-name
            </var>
Default handler: &rbrace;
            [
            <var>
              release-date
            </var>
            ]
          </code>
          . An example:
          <code>
            \LoadClass[twoside]
Default handler: &lbrace;
            article
Default handler: &rbrace;
          </code>
          .
        </para>
        <para>
          The
          <var>
            options-list
          </var>
          , if present, is a comma-separated list. The
          <var>
            release-date
          </var>
           is also optional. If present it must have the form
          <code>
            YYYY/MM/DD
          </code>
          .
Default handler: <!-- c BTW, there are at-macros documented in macros2e.pdf to check the version -->
Default handler: <!-- c and do some actions conditionnally on version later or not to some -->
Default handler: <!-- c date. -->
        </para>
        <para>
          If you request
          <var>
            release-date
          </var>
           and the date of the package installed on your system is earlier, then you get a warning on the screen and in the log like this:
        </para>
        <example endspaces=" ">
          <pre xml:space="preserve">
            You have requested, on input line 4, version `2038/01/19' of document class article, but only version `2014/09/29 v1.4h Standard LaTeX document class' is available.
          </pre>
        </example>
        <findex index="fn" spaces=" ">
          <indexterm index="fn" number="537" mergedindex="cp">
            \PassOptionsToClass
            <r>
              , ignoring
            </r>
          </indexterm>
        </findex>
        <para>
          The command version
          <code>
            \LoadClassWithOptions
          </code>
           uses the list of options for the current class. This means it ignores any options passed to it via
          <code>
            \PassOptionsToClass
          </code>
          . This is a convenience command that lets you build classes on existing ones, such as the standard
          <code>
            article
          </code>
           class, without having to track which options were passed.
        </para>
      </subsection>
      <node name="_005cNeedsTeXFormat" spaces=" ">
        <nodename>
          \NeedsTeXFormat
        </nodename>
        <nodenext automatic="on">
          \OptionNotUsed
        </nodenext>
        <nodeprev automatic="on">
          \LoadClass
          &
           \LoadClassWithOptions
        </nodeprev>
        <nodeup automatic="on">
          Class and package commands
        </nodeup>
      </node>
      <subsection spaces=" ">
        <sectiontitle>
          <code>
            \NeedsTeXFormat
          </code>
        </sectiontitle>
        <findex index="fn" spaces=" ">
          <indexterm index="fn" number="538" mergedindex="cp">
            \NeedsTeXFormat
          </indexterm>
        </findex>
        <cindex index="cp" spaces=" ">
          <indexterm index="cp" number="583">
            format, requiring
          </indexterm>
        </cindex>
        <cindex index="cp" spaces=" ">
          <indexterm index="cp" number="584">
            version of format, requiring
          </indexterm>
        </cindex>
        <cindex index="cp" spaces=" ">
          <indexterm index="cp" number="585">
            date of format, requiring
          </indexterm>
        </cindex>
        <para>
          Synopsis:
        </para>
        <example endspaces=" ">
          <pre xml:space="preserve">
            \NeedsTeXFormat
Default handler: &lbrace;
            <var>
              format
            </var>
Default handler: &rbrace;
            [
            <var>
              format-date
            </var>
            ]
          </pre>
        </example>
        <para>
          Specifies the format that this class must be run under. Often issued as the first line of a class file, and most often used as:
          <code>
            \NeedsTeXFormat
Default handler: &lbrace;
            LaTeX2e
Default handler: &rbrace;
          </code>
          . When a document using that class is processed, the format being run must exactly match the
          <var>
            format
          </var>
           name given, including case. If it does not match then execution stops with an error like
          <samp>
            This file needs format `LaTeX2e' but this is `plain'.
          </samp>
          .
        </para>
        <para>
          To require a version of the format that you know to have certain features, include the optional
          <var>
            format-date
          </var>
           on which those features were implemented. If present, it must be in the form
          <code>
            YYYY/MM/DD
          </code>
          . If the format version installed on your system is earlier than
          <var>
            format date
          </var>
           then you get a warning like this.
        </para>
        <example endspaces=" ">
          <pre xml:space="preserve">
            You have requested release `2038/01/20' of LaTeX, but only release `2016/02/01' is available.
          </pre>
        </example>
      </subsection>
      <node name="_005cOptionNotUsed" spaces=" ">
        <nodename>
          \OptionNotUsed
        </nodename>
        <nodenext automatic="on">
          \PassOptionsToClass
          &
           \PassOptionsToPackage
        </nodenext>
        <nodeprev automatic="on">
          \NeedsTeXFormat
        </nodeprev>
        <nodeup automatic="on">
          Class and package commands
        </nodeup>
      </node>
      <subsection spaces=" ">
        <sectiontitle>
          <code>
            \OptionNotUsed
          </code>
        </sectiontitle>
        <findex index="fn" spaces=" ">
          <indexterm index="fn" number="539" mergedindex="cp">
            \OptionNotUsed
          </indexterm>
        </findex>
        <cindex index="cp" spaces=" ">
          <indexterm index="cp" number="586">
            unused options, adding to list
          </indexterm>
        </cindex>
        <cindex index="cp" spaces=" ">
          <indexterm index="cp" number="587">
            options, list of unused
          </indexterm>
        </cindex>
        <para>
          Adds the current option to the list of unused options. Can only be used within the
          <var>
            code
          </var>
           argument of either
          <code>
            \DeclareOption
          </code>
           or
          <code>
            \DeclareOption*
          </code>
          .
        </para>
Default handler: <!-- c xx I cannot reproduce this behavior as it is documented in clsguide. -->
Default handler: <!-- c In the absence of a @code{\DeclareOption*} declaration, @LaTeX{} issues -->
Default handler: <!-- c on the console a warning like @code{LaTeX Warning: Unused global -->
Default handler: <!-- c option(s): [unusedoption].} with the list of not-used options when it -->
Default handler: <!-- c reaches @code{\begin@{document@}}. -->
      </subsection>
      <node name="_005cPassOptionsToClass-_0026-_005cPassOptionsToPackage" spaces=" ">
        <nodename>
          \PassOptionsToClass
          &
           \PassOptionsToPackage
        </nodename>
        <nodenext automatic="on">
          \ProcessOptions
        </nodenext>
        <nodeprev automatic="on">
          \OptionNotUsed
        </nodeprev>
        <nodeup automatic="on">
          Class and package commands
        </nodeup>
      </node>
      <subsection spaces=" ">
        <sectiontitle>
          <code>
            \PassOptionsToClass
          </code>
          &
          <code>
            \PassOptionsToPackage
          </code>
        </sectiontitle>
        <anchor name="_005cPassOptionsToClass">
          \PassOptionsToClass
        </anchor>
        <anchor name="_005cPassOptionsToPackage">
          \PassOptionsToPackage
        </anchor>
        <findex index="fn" spaces=" ">
          <indexterm index="fn" number="540" mergedindex="cp">
            \PassOptionsToClass
          </indexterm>
        </findex>
        <findex index="fn" spaces=" ">
          <indexterm index="fn" number="541" mergedindex="cp">
            \PassOptionsToPackage
          </indexterm>
        </findex>
        <para>
          Synopses:
        </para>
        <example endspaces=" ">
          <pre xml:space="preserve">
            \PassOptionsToClass
Default handler: &lbrace;
            <var>
              options
            </var>
Default handler: &rbrace;
Default handler: &lbrace;
            <var>
              clsname
            </var>
Default handler: &rbrace;
             \PassOptionsToPackage
Default handler: &lbrace;
            <var>
              option
            </var>
Default handler: &rbrace;
Default handler: &lbrace;
            <var>
              pkgname
            </var>
Default handler: &rbrace;
          </pre>
        </example>
        <para>
          Adds the options in the comma-separated list
          <var>
            options
          </var>
           to the options used by any future
          <code>
            \RequirePackage
          </code>
           or
          <code>
            \usepackage
          </code>
           command for the class
          <var>
            clsname
          </var>
           or the package
          <var>
            pkgname
          </var>
          , respectively.
        </para>
        <cindex index="cp" spaces=" ">
          <indexterm index="cp" number="588">
            option clash
          </indexterm>
        </cindex>
        <cindex index="cp" spaces=" ">
          <indexterm index="cp" number="589">
            conflict between package options
          </indexterm>
        </cindex>
        <para>
          The reason for these commands is that although you may load a package any number of times with no options, if you can specify options only the first time you load the package. Loading a package with options more than once will get you an error like
          <code>
            Option clash for package foo.
          </code>
          .
Default handler: &latex;
           throws an error even if there is no conflict between the options.
        </para>
        <para>
          If your own code is bringing in a package twice then you can combine the calls; for example, replacing the two
        </para>
        <example endspaces=" ">
          <pre xml:space="preserve">
            \RequirePackage[landscape]
Default handler: &lbrace;
            geometry
Default handler: &rbrace;
             \RequirePackage[margins=1in]
Default handler: &lbrace;
            geometry
Default handler: &rbrace;
          </pre>
        </example>
        <noindent/>
        <para>
          with the single command
        </para>
        <example endspaces=" ">
          <pre xml:space="preserve">
            \RequirePackage[landscape,margins=1in]
Default handler: &lbrace;
            geometry
Default handler: &rbrace;
          </pre>
        </example>
        <para>
          However, suppose you are loading
          <file>
            firstpkg
          </file>
           and inside that package it loads
          <file>
            secondpkg
          </file>
          , and you need
          <code>
            secondpkg
          </code>
           to be loaded with option
          <code>
            draft
          </code>
          . Then before load the first package you must tell
Default handler: &latex;
           about the desired options for the second package, like this:
        </para>
        <example endspaces=" ">
          <pre xml:space="preserve">
            \PassOptionsToPackage
Default handler: &lbrace;
            draft
Default handler: &rbrace;
Default handler: &lbrace;
            secondpkg
Default handler: &rbrace;
             \RequirePackage
Default handler: &lbrace;
            firstpkg
Default handler: &rbrace;
          </pre>
        </example>
        <noindent/>
        <para>
          If
          <code>
            firstpkg.sty
          </code>
           loads an option in conflict with what you want then you may have to alter its source, or yours.
        </para>
        <para>
          These commands are useful for general users as well as class and package writers. For instance, suppose a user wants to load the
          <code>
            graphicx
          </code>
           package with the option
          <code>
            draft
          </code>
           and also wants to use a class
          <code>
            foo
          </code>
           that loads the
          <code>
            graphicx
          </code>
           package, but without that option. The user could start their
Default handler: &latex;
           file with
          <code>
            \PassOptionsToPackage
Default handler: &lbrace;
            draft
Default handler: &rbrace;
Default handler: &lbrace;
            graphicx
Default handler: &rbrace;
             \documentclass
Default handler: &lbrace;
            foo
Default handler: &rbrace;
          </code>
          .
        </para>
      </subsection>
      <node name="_005cProcessOptions" spaces=" ">
        <nodename>
          \ProcessOptions
        </nodename>
        <nodenext automatic="on">
          \ProvidesClass
          &
           \ProvidesPackage
        </nodenext>
        <nodeprev automatic="on">
          \PassOptionsToClass
          &
           \PassOptionsToPackage
        </nodeprev>
        <nodeup automatic="on">
          Class and package commands
        </nodeup>
      </node>
      <subsection spaces=" ">
        <sectiontitle>
          <code>
            \ProcessOptions
          </code>
        </sectiontitle>
        <findex index="fn" spaces=" ">
          <indexterm index="fn" number="542" mergedindex="cp">
            \ProcessOptions
          </indexterm>
        </findex>
        <cindex index="cp" spaces=" ">
          <indexterm index="cp" number="590">
            processing options
          </indexterm>
        </cindex>
        <cindex index="cp" spaces=" ">
          <indexterm index="cp" number="591">
            options, processing
          </indexterm>
        </cindex>
        <para>
          Synopsis:
        </para>
        <example endspaces=" ">
          <pre xml:space="preserve">
            \ProcessOptions
            <var>
              \
Default handler: &arobase;
              options
            </var>
             \ProcessOptions*
            <var>
              \
Default handler: &arobase;
              options
            </var>
          </pre>
        </example>
        <para>
          Execute the code for each option that the user has invoked. Invoke it in the class file as
          <code>
            \ProcessOptions\relax
          </code>
           (because of the existence of the starred version, described below).
        </para>
        <cindex index="cp" spaces=" ">
          <indexterm index="cp" number="592">
            options, global and local
          </indexterm>
        </cindex>
        <cindex index="cp" spaces=" ">
          <indexterm index="cp" number="593">
            local options
          </indexterm>
        </cindex>
        <cindex index="cp" spaces=" ">
          <indexterm index="cp" number="594">
            global options
          </indexterm>
        </cindex>
        <para>
          Options come in two types.
          <dfn>
            Local options
          </dfn>
           have been specified for this particular package in
          <code>
            \usepackage[
            <var>
              options
            </var>
            ]
          </code>
          ,
          <code>
            \RequirePackage[
            <var>
              options
            </var>
            ]
          </code>
          , or the
          <var>
            options
          </var>
           argument of
          <code>
            \PassOptionsToPackage
Default handler: &lbrace;
            <var>
              options
            </var>
Default handler: &rbrace;
          </code>
          .
          <dfn>
            Global options
          </dfn>
           are those given by the class user in
          <code>
            \documentclass[
            <var>
              options
            </var>
            ]
          </code>
          . If an option is specified both locally and globally then it is local.
        </para>
        <para>
          When
          <code>
            \ProcessOptions
          </code>
           is called for a package
          <file>
            pkg.sty
          </file>
          , the following happens:
        </para>
        <enumerate first="1" endspaces=" ">
          <listitem>
            <para>
              For each option
              <var>
                option
              </var>
               so far declared with
              <code>
                \DeclareOption
              </code>
              ,
              <code>
                \ProcessOptions
              </code>
               looks to see if that option is either global or local for
              <code>
                pkg
              </code>
              . If so, then it executes the declared code. This is done in the order in which these options were given in
              <file>
                pkg.sty
              </file>
              .
            </para>
          </listitem>
          <listitem>
            <para>
              For each remaining local option, it executes the command
              <code>
                \ds
Default handler: &arobase;
              </code>
              <var>
                option
              </var>
               if it has been defined somewhere (other than by a
              <code>
                \DeclareOption
              </code>
              ); otherwise, it executes the default option code given in
              <code>
                \DeclareOption*
              </code>
              . If no default option code has been declared then it gives an error message. This is done in the order in which these options were specified.
            </para>
          </listitem>
        </enumerate>
        <para>
          When
          <code>
            \ProcessOptions
          </code>
           is called for a class it works in the same way except that all options are local, and the default
          <var>
            code
          </var>
           for
          <code>
            \DeclareOption*
          </code>
           is
          <code>
            \OptionNotUsed
          </code>
           rather than an error.
        </para>
        <para>
          The starred version
          <code>
            \ProcessOptions*
          </code>
           executes the options in the order specified in the calling commands, rather than in the order of declaration in the class or package. For a package, this means that the global options are processed first.
        </para>
      </subsection>
      <node name="_005cProvidesClass-_0026-_005cProvidesPackage" spaces=" ">
        <nodename>
          \ProvidesClass
          &
           \ProvidesPackage
        </nodename>
        <nodenext automatic="on">
          \ProvidesFile
        </nodenext>
        <nodeprev automatic="on">
          \ProcessOptions
        </nodeprev>
        <nodeup automatic="on">
          Class and package commands
        </nodeup>
      </node>
      <subsection spaces=" ">
        <sectiontitle>
          <code>
            \ProvidesClass
          </code>
          &
          <code>
            \ProvidesPackage
          </code>
        </sectiontitle>
        <anchor name="_005cProvidesClass">
          \ProvidesClass
        </anchor>
        <anchor name="_005cProvidesPackage">
          \ProvidesPackage
        </anchor>
        <findex index="fn" spaces=" ">
          <indexterm index="fn" number="543" mergedindex="cp">
            \ProvidesClass
          </indexterm>
        </findex>
        <findex index="fn" spaces=" ">
          <indexterm index="fn" number="544" mergedindex="cp">
            \ProvidesPackage
          </indexterm>
        </findex>
        <para>
          Synopses:
        </para>
        <example endspaces=" ">
          <pre xml:space="preserve">
            \ProvidesClass
Default handler: &lbrace;
            <var>
              clsname
            </var>
Default handler: &rbrace;
            [
            <var>
              release-date
            </var>
            <r>
              [
            </r>
            <var>
              info-text
            </var>
            <r>
              ]
            </r>
            ] \ProvidesPackage
Default handler: &lbrace;
            <var>
              pkgname
            </var>
Default handler: &rbrace;
            [
            <var>
              release-date
            </var>
            <r>
              [
            </r>
            <var>
              info-text
            </var>
            <r>
              ]
            </r>
            ]
          </pre>
        </example>
        <para>
          Identifies the class or package being defined, printing a message to the screen and the log file.
        </para>
        <para>
          When you load a class or package, for example with
          <code>
            \documentclass
Default handler: &lbrace;
            smcmemo
Default handler: &rbrace;
          </code>
           or
          <code>
            \usepackage
Default handler: &lbrace;
            test
Default handler: &rbrace;
          </code>
          ,
Default handler: &latex;
           inputs a file (
          <file>
            smcmemo.cls
          </file>
           and
          <file>
            test.sty
          </file>
          , respectively). If the name of the file does not match the class or package name declared in it then you get a warning. Thus, if you invoke
          <code>
            \documentclass
Default handler: &lbrace;
            smcmemo
Default handler: &rbrace;
          </code>
          , and the file
          <file>
            smcmemo.cls
          </file>
           has the statement
          <code>
            \ProvidesClass
Default handler: &lbrace;
            foo
Default handler: &rbrace;
          </code>
           then you get a warning like
          <code>
            You have requested document class `smcmemo', but the document class provides 'foo'.
          </code>
           This warning does not prevent
Default handler: &latex;
           from processing the rest of the class file normally.
        </para>
        <para>
          If you include the optional argument then you must include a date, before any spaces, of the form
          <code>
            YYYY/MM/DD
          </code>
          . The rest of the optional argument is free-form, although it traditionally identifies the class. It is written to the screen during compilation and to the log file. Thus, if your file
          <file>
            smcmemo.cls
          </file>
           contains the line
          <code>
            \ProvidesClass
Default handler: &lbrace;
            smcmemo
Default handler: &rbrace;
            [2008/06/01 v1.0 SMC memo class]
          </code>
           and your document
Default handler: &textrsquo;
          s first line is
          <code>
            \documentclass
Default handler: &lbrace;
            smcmemo
Default handler: &rbrace;
          </code>
           then you will see
          <code>
            Document Class: smcmemo 2008/06/01 v1.0 SMC memo class
          </code>
          .
        </para>
        <para>
          The date in the optional argument allows class and package users to ask to be warned if the version of the class or package is earlier than
          <var>
            release date
          </var>
          . For instance, a user could enter
          <code>
            \documentclass
Default handler: &lbrace;
            smcmemo
Default handler: &rbrace;
            [2018/10/12]
          </code>
           or
          <code>
            \usepackage
Default handler: &lbrace;
            foo
Default handler: &rbrace;
            [[2017/07/07]]
          </code>
           to require a class or package with certain features by specifying that it must be released no earlier than the given date. Perhaps more importantly, the date serves as documentation of the last release. (In practice, package users rarely include a date, and class users almost never do.)
        </para>
      </subsection>
      <node name="_005cProvidesFile" spaces=" ">
        <nodename>
          \ProvidesFile
        </nodename>
        <nodenext automatic="on">
          \RequirePackage
          &
           \RequirePackageWithOptions
        </nodenext>
        <nodeprev automatic="on">
          \ProvidesClass
          &
           \ProvidesPackage
        </nodeprev>
        <nodeup automatic="on">
          Class and package commands
        </nodeup>
      </node>
      <subsection spaces=" ">
        <sectiontitle>
          <code>
            \ProvidesFile
          </code>
        </sectiontitle>
        <findex index="fn" spaces=" ">
          <indexterm index="fn" number="545" mergedindex="cp">
            \ProvidesFile
          </indexterm>
        </findex>
        <para>
          Synopsis:
        </para>
        <example endspaces=" ">
          <pre xml:space="preserve">
            \ProvidesFile
Default handler: &lbrace;
            <var>
              filename
            </var>
Default handler: &rbrace;
            [
            <var>
              info-text
            </var>
            ]
          </pre>
        </example>
        <para>
          Declare a file other than the main class and package files, such as a configuration or font definition file. It writes the given information to the log file, essentially like
          <code>
            \ProvidesClass
          </code>
           and
          <code>
            \ProvidesPackage
          </code>
           (see the previous section).
        </para>
        <para>
          For example:
        </para>
        <example endspaces=" ">
          <pre xml:space="preserve">
            \ProvidesFile
Default handler: &lbrace;
            smcmemo.cfg
Default handler: &rbrace;
            [2017/10/12 config file for smcmemo.cls]
          </pre>
        </example>
        <noindent/>
        <para>
          writes this into the log:
        </para>
        <example endspaces=" ">
          <pre xml:space="preserve">
            File: smcmemo.cfg 2017/10/12 config file for smcmemo.cls
          </pre>
        </example>
      </subsection>
      <node name="_005cRequirePackage-_0026-_005cRequirePackageWithOptions" spaces=" ">
        <nodename>
          \RequirePackage
          &
           \RequirePackageWithOptions
        </nodename>
        <nodeprev automatic="on">
          \ProvidesFile
        </nodeprev>
        <nodeup automatic="on">
          Class and package commands
        </nodeup>
      </node>
      <subsection spaces=" ">
        <sectiontitle>
          <code>
            \RequirePackage
          </code>
          &
          <code>
            \RequirePackageWithOptions
          </code>
        </sectiontitle>
        <anchor name="_005cRequirePackage">
          \RequirePackage
        </anchor>
        <anchor name="_005cRequirePackageWithOptions">
          \RequirePackageWithOptions
        </anchor>
        <findex index="fn" spaces=" ">
          <indexterm index="fn" number="546" mergedindex="cp">
            \RequirePackage
          </indexterm>
        </findex>
        <findex index="fn" spaces=" ">
          <indexterm index="fn" number="547" mergedindex="cp">
            \RequirePackageWithOptions
          </indexterm>
        </findex>
        <para>
          Synopsis:
        </para>
        <example endspaces=" ">
          <pre xml:space="preserve">
            \RequirePackage[
            <var>
              option-list
            </var>
            ]
Default handler: &lbrace;
            <var>
              pkgname
            </var>
Default handler: &rbrace;
            [
            <var>
              release-date
            </var>
            ] \RequirePackageWithOptions
Default handler: &lbrace;
            <var>
              pkgname
            </var>
Default handler: &rbrace;
            [
            <var>
              release-date
            </var>
            ]
          </pre>
        </example>
        <para>
          Load a package, like the command
          <code>
            \usepackage
          </code>
           (
          <pxref label="Additional-packages">
            <xrefnodename>
              Additional packages
            </xrefnodename>
          </pxref>
          ). An example:
Default handler: &linebreak;
          <code>
            \RequirePackage[landscape,margin=1in]
Default handler: &lbrace;
            geometry
Default handler: &rbrace;
          </code>
        </para>
        <para>
          The initial optional argument
          <var>
            option-list
          </var>
          , if present, must be a comma-separated list. The trailing optional argument
          <var>
            release-date
          </var>
          , if present, must have the form
          <code>
            YYYY/MM/DD
          </code>
          . If the release date of the package as installed on your system is earlier than
          <var>
            release-date
          </var>
           then you get a warning like
          <samp>
            You have requested, on input line 9, version `2017/07/03' of package jhtest, but only version `2000/01/01' is available
          </samp>
          .
        </para>
        <para>
          The
          <code>
            \RequirePackageWithOptions
          </code>
           variant uses the list of options for the current class. This means it ignores any options passed to it via
          <code>
            \PassOptionsToClass
          </code>
          . This is a convenience command to allow easily building classes on existing ones without having to track which options were passed.
        </para>
        <para>
          The difference between
          <code>
            \usepackage
          </code>
           and
          <code>
            \RequirePackage
          </code>
           is small. The
          <code>
            \usepackage
          </code>
           command is intended to be used in documents, while
          <code>
            \RequirePackage
          </code>
           is intended for package and class files. The most significant difference in practice is that
          <code>
            \RequirePackage
          </code>
           can be used in a document before the
          <code>
            \documentclass
          </code>
           command, while
          <code>
            \usepackage
          </code>
           gives an error there. The most common need for this nowadays is for the
          <code>
            \DocumentMetadata
          </code>
           command (
          <pxref label="_005cDocumentMetadata">
            <xrefnodename>
              \DocumentMetadata
            </xrefnodename>
          </pxref>
          ).
        </para>
        <para>
          The
Default handler: &latex;
           development team strongly recommends use of these and related commands over Plain
Default handler: &nbsp;
Default handler: &tex;
Default handler: &textrsquo;
          s
          <code>
            \input
          </code>
          ; see the Class Guide (
          <url>
            <urefurl>
              https://ctan.org/pkg/clsguide
            </urefurl>
          </url>
          ).
        </para>
      </subsection>
    </section>
  </chapter>
  <node name="Counters" spaces=" ">
    <nodename>
      Counters
    </nodename>
    <nodenext automatic="on">
      Lengths
    </nodenext>
    <nodeprev automatic="on">
      Definitions
    </nodeprev>
    <nodeup automatic="on">
      Top
    </nodeup>
  </node>
  <chapter spaces=" ">
    <sectiontitle>
      Counters
    </sectiontitle>
    <cindex index="cp" spaces=" ">
      <indexterm index="cp" number="595">
        counters, a list of
      </indexterm>
    </cindex>
    <cindex index="cp" spaces=" ">
      <indexterm index="cp" number="596">
        variables, a list of
      </indexterm>
    </cindex>
    <para>
      Everything
Default handler: &latex;
       numbers for you has a counter associated with it. The name of the counter is often the same as the name of the environment or command associated with the number, except that the counter
Default handler: &textrsquo;
      s name has no backslash
Default handler: &nbsp;
      <code>
        \
      </code>
      . Thus, associated with the
      <code>
        \chapter
      </code>
       command is the
      <code>
        chapter
      </code>
       counter that keeps track of the chapter number.
    </para>
    <para>
      Below is a list of the counters used in
Default handler: &latex;
Default handler: &textrsquo;
      s standard document classes to control numbering.
    </para>
    <findex index="fn" spaces=" ">
      <indexterm index="fn" number="548" mergedindex="cp">
        part counter
      </indexterm>
    </findex>
    <findex index="fn" spaces=" ">
      <indexterm index="fn" number="549" mergedindex="cp">
        chapter counter
      </indexterm>
    </findex>
    <findex index="fn" spaces=" ">
      <indexterm index="fn" number="550" mergedindex="cp">
        section counter
      </indexterm>
    </findex>
    <findex index="fn" spaces=" ">
      <indexterm index="fn" number="551" mergedindex="cp">
        subsection counter
      </indexterm>
    </findex>
    <findex index="fn" spaces=" ">
      <indexterm index="fn" number="552" mergedindex="cp">
        subsubsection counter
      </indexterm>
    </findex>
    <findex index="fn" spaces=" ">
      <indexterm index="fn" number="553" mergedindex="cp">
        paragraph counter
      </indexterm>
    </findex>
    <findex index="fn" spaces=" ">
      <indexterm index="fn" number="554" mergedindex="cp">
        subparagraph counter
      </indexterm>
    </findex>
    <findex index="fn" spaces=" ">
      <indexterm index="fn" number="555" mergedindex="cp">
        page counter
      </indexterm>
    </findex>
    <findex index="fn" spaces=" ">
      <indexterm index="fn" number="556" mergedindex="cp">
        equation counter
      </indexterm>
    </findex>
    <findex index="fn" spaces=" ">
      <indexterm index="fn" number="557" mergedindex="cp">
        figure counter
      </indexterm>
    </findex>
    <findex index="fn" spaces=" ">
      <indexterm index="fn" number="558" mergedindex="cp">
        table counter
      </indexterm>
    </findex>
    <findex index="fn" spaces=" ">
      <indexterm index="fn" number="559" mergedindex="cp">
        footnote counter
      </indexterm>
    </findex>
    <findex index="fn" spaces=" ">
      <indexterm index="fn" number="560" mergedindex="cp">
        mpfootnote counter
      </indexterm>
    </findex>
    <findex index="fn" spaces=" ">
      <indexterm index="fn" number="561" mergedindex="cp">
        enumi counter
      </indexterm>
    </findex>
    <findex index="fn" spaces=" ">
      <indexterm index="fn" number="562" mergedindex="cp">
        enumii counter
      </indexterm>
    </findex>
    <findex index="fn" spaces=" ">
      <indexterm index="fn" number="563" mergedindex="cp">
        enumiii counter
      </indexterm>
    </findex>
    <findex index="fn" spaces=" ">
      <indexterm index="fn" number="564" mergedindex="cp">
        enumiv counter
      </indexterm>
    </findex>
    <example endspaces=" ">
      <pre xml:space="preserve">
        part paragraph figure enumi chapter subparagraph table enumii section page footnote enumiii subsection equation mpfootnote enumiv subsubsection
      </pre>
    </example>
    <para>
      The
      <code>
        mpfootnote
      </code>
       counter is used by the
      <code>
        \footnote
      </code>
       command inside of a minipage (
      <pxref label="minipage">
        <xrefnodename>
          minipage
        </xrefnodename>
      </pxref>
      ). The counters
      <code>
        enumi
      </code>
       through
      <code>
        enumiv
      </code>
       are used in the
      <code>
        enumerate
      </code>
       environment, for up to four levels of nesting (
      <pxref label="enumerate">
        <xrefnodename>
          enumerate
        </xrefnodename>
      </pxref>
      ).
    </para>
    <para>
      Counters can have any integer value but they are typically positive.
    </para>
    <para>
      New counters are created with
      <code>
        \newcounter
      </code>
      .
      <xref label="_005cnewcounter">
        <xrefnodename>
          \newcounter
        </xrefnodename>
      </xref>
      .
    </para>
    <menu endspaces=" ">
      <menuentry>
        <menuleadingtext>
          *
        </menuleadingtext>
        <menunode>
          \alph \Alph \arabic \roman \Roman \fnsymbol
        </menunode>
        <menuseparator>
          ::
        </menuseparator>
        <menudescription>
          <pre xml:space="preserve">
            Print value of a counter.
          </pre>
        </menudescription>
      </menuentry>
      <menuentry>
        <menuleadingtext>
          *
        </menuleadingtext>
        <menunode>
          \usecounter
        </menunode>
        <menuseparator>
          ::
        </menuseparator>
        <menudescription>
          <pre xml:space="preserve">
            Use a specified counter in a list environment.
          </pre>
        </menudescription>
      </menuentry>
      <menuentry>
        <menuleadingtext>
          *
        </menuleadingtext>
        <menunode>
          \value
        </menunode>
        <menuseparator>
          ::
        </menuseparator>
        <menudescription>
          <pre xml:space="preserve">
            Use the value of a counter in an expression.
          </pre>
        </menudescription>
      </menuentry>
      <menuentry>
        <menuleadingtext>
          *
        </menuleadingtext>
        <menunode>
          \setcounter
        </menunode>
        <menuseparator>
          ::
        </menuseparator>
        <menudescription>
          <pre xml:space="preserve">
            Set the value of a counter.
          </pre>
        </menudescription>
      </menuentry>
      <menuentry>
        <menuleadingtext>
          *
        </menuleadingtext>
        <menunode>
          \addtocounter
        </menunode>
        <menuseparator>
          ::
        </menuseparator>
        <menudescription>
          <pre xml:space="preserve">
            Add a quantity to a counter.
          </pre>
        </menudescription>
      </menuentry>
      <menuentry>
        <menuleadingtext>
          *
        </menuleadingtext>
        <menunode>
          \refstepcounter
        </menunode>
        <menuseparator>
          ::
        </menuseparator>
        <menudescription>
          <pre xml:space="preserve">
            Add to a counter.
          </pre>
        </menudescription>
      </menuentry>
      <menuentry>
        <menuleadingtext>
          *
        </menuleadingtext>
        <menunode>
          \stepcounter
        </menunode>
        <menuseparator>
          ::
        </menuseparator>
        <menudescription>
          <pre xml:space="preserve">
            Add to a counter, resetting subsidiary counters.
          </pre>
        </menudescription>
      </menuentry>
      <menuentry>
        <menuleadingtext>
          *
        </menuleadingtext>
        <menunode>
          \day
          &
           \month
          &
           \year
        </menunode>
        <menuseparator>
          ::
        </menuseparator>
        <menudescription>
          <pre xml:space="preserve">
            Numeric date values.
          </pre>
        </menudescription>
      </menuentry>
    </menu>
    <node name="_005calph-_005cAlph-_005carabic-_005croman-_005cRoman-_005cfnsymbol" spaces=" ">
      <nodename>
        \alph \Alph \arabic \roman \Roman \fnsymbol
      </nodename>
      <nodenext automatic="on">
        \usecounter
      </nodenext>
      <nodeup automatic="on">
        Counters
      </nodeup>
    </node>
    <section spaces=" ">
      <sectiontitle>
        <code>
          \alph \Alph \arabic \roman \Roman \fnsymbol
        </code>
        : Printing counters
      </sectiontitle>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="597">
          counters, printing
        </indexterm>
      </cindex>
      <para>
        Print the value of a counter, in a specified style. For instance, if the counter
        <var>
          counter
        </var>
         has the value 1 then a
        <code>
          \alph
Default handler: &lbrace;
          <var>
            counter
          </var>
Default handler: &rbrace;
        </code>
         in your source will result in a lowercase letter
Default handler: &nbsp;
        a appearing in the output.
      </para>
      <para>
        All of these commands take a single counter as an argument, for instance,
        <code>
          \alph
Default handler: &lbrace;
          enumi
Default handler: &rbrace;
        </code>
        . Note that the counter name does not start with a backslash.
      </para>
      <ftable commandarg="code" spaces=" " endspaces=" ">
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                <indexterm index="fn" number="565" mergedindex="cp">
                  \alph
Default handler: &lbrace;
                  <var>
                    counter
                  </var>
Default handler: &rbrace;
                </indexterm>
                \alph
Default handler: &lbrace;
                <var>
                  counter
                </var>
Default handler: &rbrace;
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <para>
              Print the value of
              <var>
                counter
              </var>
               in lowercase letters:
Default handler: &textlsquo;
              a
Default handler: &textrsquo;
              ,
Default handler: &textlsquo;
              b
Default handler: &textrsquo;
              ,
Default handler: &enddots;
               If the counter
Default handler: &textrsquo;
              s value is less than 1 or more than 26 then you get
              <samp>
                LaTeX Error: Counter too large.
              </samp>
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                <indexterm index="fn" number="566" mergedindex="cp">
                  \Alph
Default handler: &lbrace;
                  <var>
                    counter
                  </var>
Default handler: &rbrace;
                </indexterm>
                \Alph
Default handler: &lbrace;
                <var>
                  counter
                </var>
Default handler: &rbrace;
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <para>
              Print in uppercase letters:
Default handler: &textlsquo;
              A
Default handler: &textrsquo;
              ,
Default handler: &textlsquo;
              B
Default handler: &textrsquo;
              ,
Default handler: &enddots;
               If the counter
Default handler: &textrsquo;
              s value is less than 1 or more than 26 then you get
              <samp>
                LaTeX Error: Counter too large.
              </samp>
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                <indexterm index="fn" number="567" mergedindex="cp">
                  \arabic
Default handler: &lbrace;
                  <var>
                    counter
                  </var>
Default handler: &rbrace;
                </indexterm>
                \arabic
Default handler: &lbrace;
                <var>
                  counter
                </var>
Default handler: &rbrace;
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <para>
              Print in Arabic numbers such as
              <samp>
                5
              </samp>
               or
              <samp>
                -2
              </samp>
              .
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                <indexterm index="fn" number="568" mergedindex="cp">
                  \roman
Default handler: &lbrace;
                  <var>
                    counter
                  </var>
Default handler: &rbrace;
                </indexterm>
                \roman
Default handler: &lbrace;
                <var>
                  counter
                </var>
Default handler: &rbrace;
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <para>
              Print in lowercase roman numerals:
Default handler: &textlsquo;
              i
Default handler: &textrsquo;
              ,
Default handler: &textlsquo;
              ii
Default handler: &textrsquo;
              ,
Default handler: &enddots;
               If the counter
Default handler: &textrsquo;
              s value is less than 1 then you get no warning or error but
Default handler: &latex;
               does not print anything in the output.
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                <indexterm index="fn" number="569" mergedindex="cp">
                  \Roman
Default handler: &lbrace;
                  <var>
                    counter
                  </var>
Default handler: &rbrace;
                </indexterm>
                \Roman
Default handler: &lbrace;
                <var>
                  counter
                </var>
Default handler: &rbrace;
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <para>
              Print in uppercase roman numerals:
Default handler: &textlsquo;
              I
Default handler: &textrsquo;
              ,
Default handler: &textlsquo;
              II
Default handler: &textrsquo;
              ,
Default handler: &enddots;
               If the counter
Default handler: &textrsquo;
              s value is less than 1 then you get no warning or error but
Default handler: &latex;
               does not print anything in the output.
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                <indexterm index="fn" number="570" mergedindex="cp">
                  \fnsymbol
Default handler: &lbrace;
                  <var>
                    counter
                  </var>
Default handler: &rbrace;
                </indexterm>
                \fnsymbol
Default handler: &lbrace;
                <var>
                  counter
                </var>
Default handler: &rbrace;
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <para>
              Prints the value of
              <var>
                counter
              </var>
               using a sequence of nine symbols that are traditionally used for labeling footnotes. The value of
              <var>
                counter
              </var>
               should be between
Default handler: &nbsp;
              1 and
Default handler: &nbsp;
              9, inclusive. If the counter
Default handler: &textrsquo;
              s value is less than 0 or more than 9 then you get
              <samp>
                LaTeX Error: Counter too large
              </samp>
              , while if it is 0 then you get no error or warning but
Default handler: &latex;
               does not output anything.
            </para>
            <para>
              Here are the symbols:
            </para>
            <multitable spaces=" " endspaces=" ">
              <columnfractions spaces=" " line=".11 .30 .30 .29">
                <columnfraction value=".11"/>
                <columnfraction value=".30"/>
                <columnfraction value=".30"/>
                <columnfraction value=".29"/>
              </columnfractions>
              <thead>
                <row>
                  <entry command="headitem">
                    <para>
                      Number
                    </para>
                  </entry>
                  <entry command="tab">
                    <para>
                      Name
                    </para>
                  </entry>
                  <entry command="tab">
                    <para>
                      Command
                    </para>
                  </entry>
                  <entry command="tab">
                    <para>
                      Symbol
                    </para>
                  </entry>
                </row>
              </thead>
              <tbody>
                <row>
                  <entry command="item">
                    <para>
                      1
                    </para>
                  </entry>
                  <entry command="tab">
                    <para>
                      asterisk
                    </para>
                  </entry>
                  <entry command="tab">
                    <para>
                      <code>
                        \ast
                      </code>
                    </para>
                  </entry>
                  <entry command="tab">
                    <para>
                      *
Default handler: <!-- c -->
                    </para>
                  </entry>
                </row>
                <row>
                  <entry command="item">
                    <para>
                      2
                    </para>
                  </entry>
                  <entry command="tab">
                    <para>
                      dagger
                    </para>
                  </entry>
                  <entry command="tab">
                    <para>
                      <code>
                        \dagger
                      </code>
                    </para>
                  </entry>
                  <entry command="tab">
                    <para>
                      <u>
                        2020
                      </u>
                    </para>
                  </entry>
                </row>
                <row>
                  <entry command="item">
                    <para>
                      3
                    </para>
                  </entry>
                  <entry command="tab">
                    <para>
                      ddagger
                    </para>
                  </entry>
                  <entry command="tab">
                    <para>
                      <code>
                        \ddagger
                      </code>
                    </para>
                  </entry>
                  <entry command="tab">
                    <para>
                      <u>
                        2021
                      </u>
                    </para>
                  </entry>
                </row>
                <row>
                  <entry command="item">
                    <para>
                      4
                    </para>
                  </entry>
                  <entry command="tab">
                    <para>
                      section-sign
                    </para>
                  </entry>
                  <entry command="tab">
                    <para>
                      <code>
                        \S
                      </code>
                    </para>
                  </entry>
                  <entry command="tab">
                    <para>
                      <u>
                        00A7
                      </u>
                    </para>
                  </entry>
                </row>
                <row>
                  <entry command="item">
                    <para>
                      5
                    </para>
                  </entry>
                  <entry command="tab">
                    <para>
                      paragraph-sign
                    </para>
                  </entry>
                  <entry command="tab">
                    <para>
                      <code>
                        \P
                      </code>
                    </para>
                  </entry>
                  <entry command="tab">
                    <para>
                      <u>
                        00B6
                      </u>
                    </para>
                  </entry>
                </row>
                <row>
                  <entry command="item">
                    <para>
                      6
                    </para>
                  </entry>
                  <entry command="tab">
                    <para>
                      double-vert
                    </para>
                  </entry>
                  <entry command="tab">
                    <para>
                      <code>
                        \parallel
                      </code>
                    </para>
                  </entry>
                  <entry command="tab">
                    <para>
                      <u>
                        2016
                      </u>
                    </para>
                  </entry>
                </row>
                <row>
                  <entry command="item">
                    <para>
                      7
                    </para>
                  </entry>
                  <entry command="tab">
                    <para>
                      double-asterisk
                    </para>
                  </entry>
                  <entry command="tab">
                    <para>
                      <code>
                        \ast\ast
                      </code>
                    </para>
                  </entry>
                  <entry command="tab">
                    <para>
                      **
Default handler: <!-- c -->
                    </para>
                  </entry>
                </row>
                <row>
                  <entry command="item">
                    <para>
                      8
                    </para>
                  </entry>
                  <entry command="tab">
                    <para>
                      double-dagger
                    </para>
                  </entry>
                  <entry command="tab">
                    <para>
                      <code>
                        \dagger\dagger
                      </code>
                    </para>
                  </entry>
                  <entry command="tab">
                    <para>
                      <u>
                        2020
                      </u>
                      <u>
                        2020
                      </u>
                    </para>
                  </entry>
                </row>
                <row>
                  <entry command="item">
                    <para>
                      9
                    </para>
                  </entry>
                  <entry command="tab">
                    <para>
                      double-ddagger
                    </para>
                  </entry>
                  <entry command="tab">
                    <para>
                      <code>
                        \ddagger\ddagger
                      </code>
                    </para>
                  </entry>
                  <entry command="tab">
                    <para>
                      <u>
                        2021
                      </u>
                      <u>
                        2021
                      </u>
                    </para>
                  </entry>
                </row>
              </tbody>
            </multitable>
          </tableitem>
        </tableentry>
      </ftable>
    </section>
    <node name="_005cusecounter" spaces=" ">
      <nodename>
        \usecounter
      </nodename>
      <nodenext automatic="on">
        \value
      </nodenext>
      <nodeprev automatic="on">
        \alph \Alph \arabic \roman \Roman \fnsymbol
      </nodeprev>
      <nodeup automatic="on">
        Counters
      </nodeup>
    </node>
    <section spaces=" ">
      <sectiontitle>
        <code>
          \usecounter
        </code>
      </sectiontitle>
      <findex index="fn" spaces=" ">
        <indexterm index="fn" number="571" mergedindex="cp">
          \usecounter
        </indexterm>
      </findex>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="598">
          list items, specifying counter
        </indexterm>
      </cindex>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="599">
          numbered items, specifying counter
        </indexterm>
      </cindex>
      <para>
        Synopsis:
      </para>
      <example endspaces=" ">
        <pre xml:space="preserve">
          \usecounter
Default handler: &lbrace;
          <var>
            counter
          </var>
Default handler: &rbrace;
        </pre>
      </example>
      <para>
        Used in the second argument of the
        <code>
          list
        </code>
         environment (
        <pxref label="list">
          <xrefnodename>
            list
          </xrefnodename>
        </pxref>
        ), this declares that list items will be numbered by
        <var>
          counter
        </var>
        . It initializes
        <var>
          counter
        </var>
         to zero, and arranges that when
        <code>
          \item
        </code>
         is called without its optional argument then
        <var>
          counter
        </var>
         is incremented by
        <code>
          \refstepcounter
        </code>
        , making its value be the current
        <code>
          ref
        </code>
         value (
        <pxref label="_005cref">
          <xrefnodename>
            \ref
          </xrefnodename>
        </pxref>
        ). This command is fragile (
        <pxref label="_005cprotect">
          <xrefnodename>
            \protect
          </xrefnodename>
        </pxref>
        ).
      </para>
      <para>
        Put in the document preamble, this example makes a new list environment enumerated with
        <var>
          testcounter
        </var>
        :
      </para>
      <example endspaces=" ">
        <pre xml:space="preserve">
          \newcounter
Default handler: &lbrace;
          testcounter
Default handler: &rbrace;
           \newenvironment
Default handler: &lbrace;
          test
Default handler: &rbrace;
Default handler: &lbrace;
          % \begin
Default handler: &lbrace;
          list
Default handler: &rbrace;
Default handler: &lbrace;
Default handler: &rbrace;
Default handler: &lbrace;
          % \usecounter
Default handler: &lbrace;
          testcounter
Default handler: &rbrace;
Default handler: &rbrace;
Default handler: &rbrace;
Default handler: &lbrace;
          % \end
Default handler: &lbrace;
          list
Default handler: &rbrace;
Default handler: &rbrace;
        </pre>
      </example>
    </section>
    <node name="_005cvalue" spaces=" ">
      <nodename>
        \value
      </nodename>
      <nodenext automatic="on">
        \setcounter
      </nodenext>
      <nodeprev automatic="on">
        \usecounter
      </nodeprev>
      <nodeup automatic="on">
        Counters
      </nodeup>
    </node>
    <section spaces=" ">
      <sectiontitle>
        <code>
          \value
        </code>
      </sectiontitle>
      <findex index="fn" spaces=" ">
        <indexterm index="fn" number="572" mergedindex="cp">
          \value
        </indexterm>
      </findex>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="600">
          counters, getting value of
        </indexterm>
      </cindex>
      <para>
        Synopsis:
      </para>
      <example endspaces=" ">
        <pre xml:space="preserve">
          \value
Default handler: &lbrace;
          <var>
            counter
          </var>
Default handler: &rbrace;
        </pre>
      </example>
      <para>
        Expands to the value of the counter
        <var>
          counter
        </var>
        . (Note that the name of a counter does not begin with a backslash.)
      </para>
      <para>
        This example outputs
        <samp>
          Test counter is
Default handler: &nbsp;
          6. Other counter is
Default handler: &nbsp;
          5.
        </samp>
        .
      </para>
      <example endspaces=" ">
        <pre xml:space="preserve">
          \newcounter
Default handler: &lbrace;
          test
Default handler: &rbrace;
           \setcounter
Default handler: &lbrace;
          test
Default handler: &rbrace;
Default handler: &lbrace;
          5
Default handler: &rbrace;
           \newcounter
Default handler: &lbrace;
          other
Default handler: &rbrace;
           \setcounter
Default handler: &lbrace;
          other
Default handler: &rbrace;
Default handler: &lbrace;
          \value
Default handler: &lbrace;
          test
Default handler: &rbrace;
Default handler: &rbrace;
           \addtocounter
Default handler: &lbrace;
          test
Default handler: &rbrace;
Default handler: &lbrace;
          1
Default handler: &rbrace;
           Test counter is \arabic
Default handler: &lbrace;
          test
Default handler: &rbrace;
          . Other counter is \arabic
Default handler: &lbrace;
          other
Default handler: &rbrace;
          .
        </pre>
      </example>
      <para>
        The
        <code>
          \value
        </code>
         command is not used for typesetting the value of the counter. For that, see
        <ref label="_005calph-_005cAlph-_005carabic-_005croman-_005cRoman-_005cfnsymbol">
          <xrefnodename>
            \alph \Alph \arabic \roman \Roman \fnsymbol
          </xrefnodename>
        </ref>
        .
      </para>
      <para>
        It is often used in
        <code>
          \setcounter
        </code>
         or
        <code>
          \addtocounter
        </code>
         but
        <code>
          \value
        </code>
         can be used anywhere that
Default handler: &latex;
         expects a number, such as in
        <code>
          \hspace
Default handler: &lbrace;
          \value
Default handler: &lbrace;
          foo
Default handler: &rbrace;
          \parindent
Default handler: &rbrace;
        </code>
        . It must not be preceded by
        <code>
          \protect
        </code>
         (
        <pxref label="_005cprotect">
          <xrefnodename>
            \protect
          </xrefnodename>
        </pxref>
        ).
      </para>
      <para>
        This example inserts
        <code>
          \hspace
Default handler: &lbrace;
          4\parindent
Default handler: &rbrace;
        </code>
        .
      </para>
      <example endspaces=" ">
        <pre xml:space="preserve">
          \setcounter
Default handler: &lbrace;
          myctr
Default handler: &rbrace;
Default handler: &lbrace;
          3
Default handler: &rbrace;
           \addtocounter
Default handler: &lbrace;
          myctr
Default handler: &rbrace;
Default handler: &lbrace;
          1
Default handler: &rbrace;
           \hspace
Default handler: &lbrace;
          \value
Default handler: &lbrace;
          myctr
Default handler: &rbrace;
          \parindent
Default handler: &rbrace;
        </pre>
      </example>
    </section>
    <node name="_005csetcounter" spaces=" ">
      <nodename>
        \setcounter
      </nodename>
      <nodenext automatic="on">
        \addtocounter
      </nodenext>
      <nodeprev automatic="on">
        \value
      </nodeprev>
      <nodeup automatic="on">
        Counters
      </nodeup>
    </node>
    <section spaces=" ">
      <sectiontitle>
        <code>
          \setcounter
        </code>
      </sectiontitle>
      <findex index="fn" spaces=" ">
        <indexterm index="fn" number="573" mergedindex="cp">
          \setcounter
        </indexterm>
      </findex>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="601">
          counters, setting
        </indexterm>
      </cindex>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="602">
          setting counters
        </indexterm>
      </cindex>
      <para>
        Synopsis:
      </para>
      <example endspaces=" ">
        <pre xml:space="preserve">
          \setcounter
Default handler: &lbrace;
          <var>
            counter
          </var>
Default handler: &rbrace;
Default handler: &lbrace;
          <var>
            value
          </var>
Default handler: &rbrace;
        </pre>
      </example>
      <para>
        Globally set the counter
        <var>
          counter
        </var>
         to have the value of the
        <var>
          value
        </var>
         argument, which must be an integer. Thus, you can set a counter
Default handler: &textrsquo;
        s value as
        <code>
          \setcounter
Default handler: &lbrace;
          section
Default handler: &rbrace;
Default handler: &lbrace;
          5
Default handler: &rbrace;
        </code>
        . Note that the counter name does not start with a backslash.
      </para>
      <para>
        In this example if the counter
        <code>
          theorem
        </code>
         has value 12 then the second line will print
        <samp>
          XII
        </samp>
        .
      </para>
      <example endspaces=" ">
        <pre xml:space="preserve">
          \setcounter
Default handler: &lbrace;
          exercise
Default handler: &rbrace;
Default handler: &lbrace;
          \value
Default handler: &lbrace;
          theorem
Default handler: &rbrace;
Default handler: &rbrace;
           Here it is in Roman: \Roman
Default handler: &lbrace;
          exercise
Default handler: &rbrace;
          .
        </pre>
      </example>
    </section>
    <node name="_005caddtocounter" spaces=" ">
      <nodename>
        \addtocounter
      </nodename>
      <nodenext automatic="on">
        \refstepcounter
      </nodenext>
      <nodeprev automatic="on">
        \setcounter
      </nodeprev>
      <nodeup automatic="on">
        Counters
      </nodeup>
    </node>
    <section spaces=" ">
      <sectiontitle>
        <code>
          \addtocounter
        </code>
      </sectiontitle>
      <findex index="fn" spaces=" ">
        <indexterm index="fn" number="574" mergedindex="cp">
          \addtocounter
        </indexterm>
      </findex>
      <para>
        Synopsis:
      </para>
      <example endspaces=" ">
        <pre xml:space="preserve">
          \addtocounter
Default handler: &lbrace;
          <var>
            counter
          </var>
Default handler: &rbrace;
Default handler: &lbrace;
          <var>
            value
          </var>
Default handler: &rbrace;
        </pre>
      </example>
      <para>
        Globally increment
        <var>
          counter
        </var>
         by the amount specified by the
        <var>
          value
        </var>
         argument, which may be negative.
      </para>
      <para>
        In this example the section value appears as
        <samp>
          VII
        </samp>
        .
      </para>
      <example endspaces=" ">
        <pre xml:space="preserve">
          \setcounter
Default handler: &lbrace;
          section
Default handler: &rbrace;
Default handler: &lbrace;
          5
Default handler: &rbrace;
           \addtocounter
Default handler: &lbrace;
          section
Default handler: &rbrace;
Default handler: &lbrace;
          2
Default handler: &rbrace;
           Here it is in Roman: \Roman
Default handler: &lbrace;
          section
Default handler: &rbrace;
          .
        </pre>
      </example>
    </section>
    <node name="_005crefstepcounter" spaces=" ">
      <nodename>
        \refstepcounter
      </nodename>
      <nodenext automatic="on">
        \stepcounter
      </nodenext>
      <nodeprev automatic="on">
        \addtocounter
      </nodeprev>
      <nodeup automatic="on">
        Counters
      </nodeup>
    </node>
    <section spaces=" ">
      <sectiontitle>
        <code>
          \refstepcounter
        </code>
      </sectiontitle>
      <findex index="fn" spaces=" ">
        <indexterm index="fn" number="575" mergedindex="cp">
          \refstepcounter
        </indexterm>
      </findex>
      <para>
        Synopsis:
      </para>
      <example endspaces=" ">
        <pre xml:space="preserve">
          \refstepcounter
Default handler: &lbrace;
          <var>
            counter
          </var>
Default handler: &rbrace;
        </pre>
      </example>
      <para>
        Globally increments the value of
        <var>
          counter
        </var>
         by one, as does
        <code>
          \stepcounter
        </code>
         (
        <pxref label="_005cstepcounter">
          <xrefnodename>
            \stepcounter
          </xrefnodename>
        </pxref>
        ). The difference is that this command resets the value of any counter numbered within it. (For the definition of
Default handler: &textldquo;
        counters numbered within
Default handler: &textrdquo;
        ,
        <pxref label="_005cnewcounter">
          <xrefnodename>
            \newcounter
          </xrefnodename>
        </pxref>
        .)
      </para>
      <para>
        In addition, this command also defines the current
        <code>
          \ref
        </code>
         value to be the result of
        <code>
          \thecounter
        </code>
        .
      </para>
      <para>
        While the counter value is set globally, the
        <code>
          \ref
        </code>
         value is set locally, i.e., inside the current group.
      </para>
    </section>
    <node name="_005cstepcounter" spaces=" ">
      <nodename>
        \stepcounter
      </nodename>
      <nodenext automatic="on">
        \day
        &
         \month
        &
         \year
      </nodenext>
      <nodeprev automatic="on">
        \refstepcounter
      </nodeprev>
      <nodeup automatic="on">
        Counters
      </nodeup>
    </node>
    <section spaces=" ">
      <sectiontitle>
        <code>
          \stepcounter
        </code>
      </sectiontitle>
      <findex index="fn" spaces=" ">
        <indexterm index="fn" number="576" mergedindex="cp">
          \stepcounter
        </indexterm>
      </findex>
      <para>
        Synopsis:
      </para>
      <example endspaces=" ">
        <pre xml:space="preserve">
          \stepcounter
Default handler: &lbrace;
          <var>
            counter
          </var>
Default handler: &rbrace;
        </pre>
      </example>
      <para>
        Globally adds one to
        <var>
          counter
        </var>
         and resets all counters numbered within it. (For the definition of
Default handler: &textldquo;
        counters numbered within
Default handler: &textrdquo;
        ,
        <pxref label="_005cnewcounter">
          <xrefnodename>
            \newcounter
          </xrefnodename>
        </pxref>
        .)
      </para>
      <para>
        This command differs from
        <code>
          \refstepcounter
        </code>
         in that this one does not influence references; that is, it does not define the current
        <code>
          \ref
        </code>
         value to be the result of
        <code>
          \thecounter
        </code>
         (
        <pxref label="_005crefstepcounter">
          <xrefnodename>
            \refstepcounter
          </xrefnodename>
        </pxref>
        ).
      </para>
    </section>
    <node name="_005cday-_0026-_005cmonth-_0026-_005cyear" spaces=" ">
      <nodename>
        \day
        &
         \month
        &
         \year
      </nodename>
      <nodeprev automatic="on">
        \stepcounter
      </nodeprev>
      <nodeup automatic="on">
        Counters
      </nodeup>
    </node>
    <section spaces=" ">
      <sectiontitle>
        <code>
          \day
        </code>
        &
        <code>
          \month
        </code>
        &
        <code>
          \year
        </code>
      </sectiontitle>
      <anchor name="_005cday">
        \day
      </anchor>
      <anchor name="_005cmonth">
        \month
      </anchor>
      <anchor name="_005cyear">
        \year
      </anchor>
      <findex index="fn" spaces=" ">
        <indexterm index="fn" number="577" mergedindex="cp">
          \day
        </indexterm>
      </findex>
      <findex index="fn" spaces=" ">
        <indexterm index="fn" number="578" mergedindex="cp">
          \month
        </indexterm>
      </findex>
      <findex index="fn" spaces=" ">
        <indexterm index="fn" number="579" mergedindex="cp">
          \year
        </indexterm>
      </findex>
      <paraDefault handler: &latex;
>
         defines the counter
        <code>
          \day
        </code>
         for the day of the month (nominally with value between 1 and 31),
        <code>
          \month
        </code>
         for the month of the year (nominally with value between 1 and 12), and
        <code>
          \year
        </code>
         for the year. When
Default handler: &tex;
         starts up, they are set from the current values on the system. The related command
        <code>
          \today
        </code>
         produces a string representing the current day (
        <pxref label="_005ctoday">
          <xrefnodename>
            \today
          </xrefnodename>
        </pxref>
        ).
      </para>
      <para>
        They counters are not updated as the job progresses so in principle they could be incorrect by the end. In addition,
Default handler: &tex;
         does no sanity check:
      </para>
      <example endspaces=" ">
        <pre xml:space="preserve">
          \day=-2 \month=13 \year=-4 \today
        </pre>
      </example>
      <noindent/>
      <para>
        gives no error or warning and results in the output
        <samp>
          -2, -4
        </samp>
         (the bogus month value produces no output).
      </para>
      <para>
        <xref label="Command-line-input">
          <xrefnodename>
            Command line input
          </xrefnodename>
        </xref>
        , to force the date to a given value from the command line.
      </para>
    </section>
  </chapter>
  <node name="Lengths" spaces=" ">
    <nodename>
      Lengths
    </nodename>
    <nodenext automatic="on">
      Making paragraphs
    </nodenext>
    <nodeprev automatic="on">
      Counters
    </nodeprev>
    <nodeup automatic="on">
      Top
    </nodeup>
  </node>
  <chapter spaces=" ">
    <sectiontitle>
      Lengths
    </sectiontitle>
    <cindex index="cp" spaces=" ">
      <indexterm index="cp" number="603">
        lengths, defining and using
      </indexterm>
    </cindex>
    <para>
      A
      <dfn>
        length
      </dfn>
       is a measure of distance. Many
Default handler: &latex;
       commands take a length as an argument.
    </para>
    <cindex index="cp" spaces=" ">
      <indexterm index="cp" number="604">
        rigid lengths
      </indexterm>
    </cindex>
    <cindex index="cp" spaces=" ">
      <indexterm index="cp" number="605">
        rubber lengths
      </indexterm>
    </cindex>
    <cindex index="cp" spaces=" ">
      <indexterm index="cp" number="606">
        dimen
        <r>
          plain
Default handler: &tex;
        </r>
      </indexterm>
    </cindex>
    <cindex index="cp" spaces=" ">
      <indexterm index="cp" number="607">
        skip
        <r>
          plain
Default handler: &tex;
        </r>
      </indexterm>
    </cindex>
    <cindex index="cp" spaces=" ">
      <indexterm index="cp" number="608">
        glue
        <r>
          plain
Default handler: &tex;
        </r>
      </indexterm>
    </cindex>
    <para>
      Lengths come in two types. A
      <dfn>
        rigid length
      </dfn>
       such as
      <code>
        10pt
      </code>
       does not contain a
      <code>
        plus
      </code>
       or
      <code>
        minus
      </code>
       component. (Plain
Default handler: &tex;
       calls this a
      <dfn>
        dimen
      </dfn>
      .) A
      <dfn>
        rubber length
      </dfn>
       (what plain
Default handler: &tex;
       calls a
      <dfn>
        skip
      </dfn>
       or
      <dfn>
        glue
      </dfn>
      ) such as with
      <code>
        1cm plus0.05cm minus0.01cm
      </code>
       can contain either or both of those components. In that rubber length, the
      <code>
        1cm
      </code>
       is the
      <dfn>
        natural length
      </dfn>
       while the other two, the
      <code>
        plus
      </code>
       and
      <code>
        minus
      </code>
       components, allow
Default handler: &tex;
       to stretch or shrink the length to optimize placement.
    </para>
    <para>
      The illustrations below use these two commands.
    </para>
    <example endspaces=" ">
      <pre xml:space="preserve">
        % make a black bar 10pt tall and #1 wide \newcommand
Default handler: &lbrace;
        \blackbar
Default handler: &rbrace;
        [1]
Default handler: &lbrace;
        \rule
Default handler: &lbrace;
        #1
Default handler: &rbrace;
Default handler: &lbrace;
        10pt
Default handler: &rbrace;
Default handler: &rbrace;
         % Make a box around #2 that is #1 wide (excluding the border) \newcommand
Default handler: &lbrace;
        \showhbox
Default handler: &rbrace;
        [2]
Default handler: &lbrace;
        % \fboxsep=0pt\fbox
Default handler: &lbrace;
        \hbox to #1
Default handler: &lbrace;
        #2
Default handler: &rbrace;
Default handler: &rbrace;
Default handler: &rbrace;
      </pre>
    </example>
    <noindent/>
    <para>
      This next example uses those commands to show a black bar 100
Default handler: &nbsp;
      points long between
      <samp>
        ABC
      </samp>
       and
      <samp>
        XYZ
      </samp>
      . This length is rigid.
    </para>
    <example endspaces=" ">
      <pre xml:space="preserve">
        ABC\showhbox
Default handler: &lbrace;
        100pt
Default handler: &rbrace;
Default handler: &lbrace;
        \blackbar
Default handler: &lbrace;
        100pt
Default handler: &rbrace;
Default handler: &rbrace;
        XYZ
      </pre>
    </example>
    <para>
      As for rubber lengths, shrinking is simpler one: with
      <code>
        1cm minus 0.05cm
      </code>
      , the natural length is 1
      <dmn>
        cm
      </dmn>
       but
Default handler: &tex;
       can shrink it down as far as 0.95
      <dmn>
        cm
      </dmn>
      . Beyond that,
Default handler: &tex;
       refuses to shrink any more. Thus, below the first one works fine, producing a space of 98
Default handler: &nbsp;
      points between the two bars.
    </para>
    <example endspaces=" ">
      <pre xml:space="preserve">
        ABC\showhbox
Default handler: &lbrace;
        300pt
Default handler: &rbrace;
Default handler: &lbrace;
        % \blackbar
Default handler: &lbrace;
        101pt
Default handler: &rbrace;
        \hspace
Default handler: &lbrace;
        100pt minus 2pt
Default handler: &rbrace;
        \blackbar
Default handler: &lbrace;
        101pt
Default handler: &rbrace;
Default handler: &rbrace;
        YYY ABC\showhbox
Default handler: &lbrace;
        300pt
Default handler: &rbrace;
Default handler: &lbrace;
        % \blackbar
Default handler: &lbrace;
        105pt
Default handler: &rbrace;
        \hspace
Default handler: &lbrace;
        100pt minus 1pt
Default handler: &rbrace;
        \blackbar
Default handler: &lbrace;
        105pt
Default handler: &rbrace;
Default handler: &rbrace;
        YYY
      </pre>
    </example>
    <noindent/>
    <para>
      But the second one gets a warning like
      <samp>
        Overfull \hbox (1.0pt too wide) detected at line 17
      </samp>
      . In the output the first
      <samp>
        Y
      </samp>
       is overwritten by the end of the black bar, because the box
Default handler: &textrsquo;
      s material is wider than the 300
      <dmn>
        pt
      </dmn>
       allocated, as
Default handler: &tex;
       has refused to shrink the total to less than 309
Default handler: &nbsp;
      points.
    </para>
    <para>
      Stretching is like shrinking except that if
Default handler: &tex;
       is asked to stretch beyond the given amount, it will do it. Here the first line is fine, producing a space of 110
Default handler: &nbsp;
      points between the bars.
    </para>
    <example endspaces=" ">
      <pre xml:space="preserve">
        ABC\showhbox
Default handler: &lbrace;
        300pt
Default handler: &rbrace;
Default handler: &lbrace;
        % \blackbar
Default handler: &lbrace;
        95pt
Default handler: &rbrace;
        \hspace
Default handler: &lbrace;
        100pt plus 10pt
Default handler: &rbrace;
        \blackbar
Default handler: &lbrace;
        95pt
Default handler: &rbrace;
Default handler: &rbrace;
        YYY ABC\showhbox
Default handler: &lbrace;
        300pt
Default handler: &rbrace;
Default handler: &lbrace;
        % \blackbar
Default handler: &lbrace;
        95pt
Default handler: &rbrace;
        \hspace
Default handler: &lbrace;
        100pt plus 1pt
Default handler: &rbrace;
        \blackbar
Default handler: &lbrace;
        95pt
Default handler: &rbrace;
Default handler: &rbrace;
        YYY
      </pre>
    </example>
    <noindent/>
    <para>
      In the second line
Default handler: &tex;
       needs a stretch of 10
Default handler: &nbsp;
      points and only 1
Default handler: &nbsp;
      point was specified.
Default handler: &tex;
       stretches the space to the required length but it gives you a warning like
      <samp>
        Underfull \hbox (badness 10000) detected at line 22
      </samp>
      . (We won
Default handler: &textrsquo;
      t discuss badness.)
    </para>
    <para>
      You can put both stretch and shrink in the same length, as in
      <code>
        1ex plus 0.05ex minus 0.02ex
      </code>
      .
    </para>
    <para>
      If
Default handler: &tex;
       is setting two or more rubber lengths then it allocates the stretch or shrink in proportion.
    </para>
    <example endspaces=" ">
      <pre xml:space="preserve">
        ABC\showhbox
Default handler: &lbrace;
        300pt
Default handler: &rbrace;
Default handler: &lbrace;
        % \blackbar
Default handler: &lbrace;
        100pt
Default handler: &rbrace;
        % left \hspace
Default handler: &lbrace;
        0pt plus 50pt
Default handler: &rbrace;
        \blackbar
Default handler: &lbrace;
        80pt
Default handler: &rbrace;
        \hspace
Default handler: &lbrace;
        0pt plus 10pt
Default handler: &rbrace;
        % middle \blackbar
Default handler: &lbrace;
        100pt
Default handler: &rbrace;
Default handler: &rbrace;
        YYY % right
      </pre>
    </example>
    <noindent/>
    <para>
      The left and right bars take up 100
Default handler: &nbsp;
      points, so the middle needs another 100. The middle bar is 80
Default handler: &nbsp;
      points so the two
      <code>
        \hspace
      </code>
Default handler: &textrsquo;
      s must stretch 20
Default handler: &nbsp;
      points. Because the two are
      <code>
        plus 50pt
      </code>
       and
      <code>
        plus 10pt
      </code>
      ,
Default handler: &tex;
       gets 5/6 of the stretch from the first space and 1/6 from the second.
    </para>
    <para>
      The
      <code>
        plus
      </code>
       or
      <code>
        minus
      </code>
       component of a rubber length can contain a
      <dfn>
        fill
      </dfn>
       component, as in
      <code>
        1in plus2fill
      </code>
      . This gives the length infinite stretchability or shrinkability so that
Default handler: &tex;
       could set it to any distance. Here the two figures will be equally spaced across the page.
    </para>
    <example endspaces=" ">
      <pre xml:space="preserve">
        \begin
Default handler: &lbrace;
        minipage
Default handler: &rbrace;
Default handler: &lbrace;
        \linewidth
Default handler: &rbrace;
         \hspace
Default handler: &lbrace;
        0pt plus 1fill
Default handler: &rbrace;
        \includegraphics
Default handler: &lbrace;
        godel.png
Default handler: &rbrace;
        % \hspace
Default handler: &lbrace;
        0pt plus 1fill
Default handler: &rbrace;
        \includegraphics
Default handler: &lbrace;
        einstein.png
Default handler: &rbrace;
        % \hspace
Default handler: &lbrace;
        0pt plus 1fill
Default handler: &rbrace;
         \end
Default handler: &lbrace;
        minipage
Default handler: &rbrace;
      </pre>
    </example>
    <paraDefault handler: &tex;
>
       has three levels of infinity for glue components:
      <code>
        fil
      </code>
      ,
      <code>
        fill
      </code>
      , and
      <code>
        filll
      </code>
      . The later ones are more infinite than the earlier ones. Ordinarily document authors only use the middle one (
      <pxref label="_005chfill">
        <xrefnodename>
          \hfill
        </xrefnodename>
      </pxref>
       and
      <pxref label="_005cvfill">
        <xrefnodename>
          \vfill
        </xrefnodename>
      </pxref>
      ).
    </para>
    <para>
      Multiplying a rubber length by a number turns it into a rigid length, so that after
      <code>
        \setlength
Default handler: &lbrace;
        \ylength
Default handler: &rbrace;
Default handler: &lbrace;
        1in plus 0.2in
Default handler: &rbrace;
      </code>
       and
      <code>
        \setlength
Default handler: &lbrace;
        \zlength
Default handler: &rbrace;
Default handler: &lbrace;
        3\ylength
Default handler: &rbrace;
      </code>
       then the value of
      <code>
        \zlength
      </code>
       is
      <code>
        3in
      </code>
      .
    </para>
    <menu endspaces=" ">
      <menuentry>
        <menuleadingtext>
          *
        </menuleadingtext>
        <menunode>
          Units of length
        </menunode>
        <menuseparator>
          ::
        </menuseparator>
        <menudescription>
          <pre xml:space="preserve">
            The units that
Default handler: &latex;
             knows.
          </pre>
        </menudescription>
      </menuentry>
      <menuentry>
        <menuleadingtext>
          *
        </menuleadingtext>
        <menunode>
          \setlength
        </menunode>
        <menuseparator>
          ::
        </menuseparator>
        <menudescription>
          <pre xml:space="preserve">
            Set the value of a length.
          </pre>
        </menudescription>
      </menuentry>
      <menuentry>
        <menuleadingtext>
          *
        </menuleadingtext>
        <menunode>
          \addtolength
        </menunode>
        <menuseparator>
          ::
        </menuseparator>
        <menudescription>
          <pre xml:space="preserve">
            Add a quantity to a length.
          </pre>
        </menudescription>
      </menuentry>
      <menuentry>
        <menuleadingtext>
          *
        </menuleadingtext>
        <menunode>
          \settodepth
        </menunode>
        <menuseparator>
          ::
        </menuseparator>
        <menudescription>
          <pre xml:space="preserve">
            Set a length to the depth of something.
          </pre>
        </menudescription>
      </menuentry>
      <menuentry>
        <menuleadingtext>
          *
        </menuleadingtext>
        <menunode>
          \settoheight
        </menunode>
        <menuseparator>
          ::
        </menuseparator>
        <menudescription>
          <pre xml:space="preserve">
            Set a length to the height of something.
          </pre>
        </menudescription>
      </menuentry>
      <menuentry>
        <menuleadingtext>
          *
        </menuleadingtext>
        <menunode>
          \settowidth
        </menunode>
        <menuseparator>
          ::
        </menuseparator>
        <menudescription>
          <pre xml:space="preserve">
            Set a length to the width of something.
          </pre>
        </menudescription>
      </menuentry>
      <menuentry>
        <menuleadingtext>
          *
        </menuleadingtext>
        <menunode>
          \stretch
        </menunode>
        <menuseparator>
          ::
        </menuseparator>
        <menudescription>
          <pre xml:space="preserve">
            Add infinite stretchability.
          </pre>
        </menudescription>
      </menuentry>
      <menuentry>
        <menuleadingtext>
          *
        </menuleadingtext>
        <menunode>
          Expressions
        </menunode>
        <menuseparator>
          ::
        </menuseparator>
        <menudescription>
          <pre xml:space="preserve">
            Compute with lengths and integers.
          </pre>
        </menudescription>
      </menuentry>
    </menu>
    <node name="Units-of-length" spaces=" ">
      <nodename>
        Units of length
      </nodename>
      <nodenext automatic="on">
        \setlength
      </nodenext>
      <nodeup automatic="on">
        Lengths
      </nodeup>
    </node>
    <section spaces=" ">
      <sectiontitle>
        Units of length
      </sectiontitle>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="609">
          units, of length
        </indexterm>
      </cindex>
      <paraDefault handler: &tex;
>
         and
Default handler: &latex;
         know about these units both inside and outside of math mode.
      </para>
      <ftable commandarg="code" spaces=" " endspaces=" ">
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                <indexterm index="fn" number="580" mergedindex="cp">
                  pt
                </indexterm>
                pt
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <cindex index="cp" spaces=" ">
              <indexterm index="cp" number="610">
                point
              </indexterm>
            </cindex>
            <anchor name="units-of-length-pt">
              units of length pt
            </anchor>
            <para>
              Point, 1/72.27 inch. The (approximate) conversion to metric units is 1
              <dmn>
                point
              </dmn>
               = .35146
              <dmn>
                mm
              </dmn>
               = .035146
              <dmn>
                cm
              </dmn>
              .
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                <indexterm index="fn" number="581" mergedindex="cp">
                  pc
                </indexterm>
                pc
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <cindex index="cp" spaces=" ">
              <indexterm index="cp" number="611">
                pica
              </indexterm>
            </cindex>
            <anchor name="units-of-length-pc">
              units of length pc
            </anchor>
            <para>
              Pica, 12 pt
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                <indexterm index="fn" number="582" mergedindex="cp">
                  in
                </indexterm>
                in
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <cindex index="cp" spaces=" ">
              <indexterm index="cp" number="612">
                inch
              </indexterm>
            </cindex>
            <anchor name="units-of-length-in">
              units of length in
            </anchor>
            <para>
              Inch, 72.27 pt
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                <indexterm index="fn" number="583" mergedindex="cp">
                  bp
                </indexterm>
                bp
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <cindex index="cp" spaces=" ">
              <indexterm index="cp" number="613">
                big point
              </indexterm>
            </cindex>
            <cindex index="cp" spaces=" ">
              <indexterm index="cp" number="614">
                PostScript point
              </indexterm>
            </cindex>
            <anchor name="units-of-length-bp">
              units of length bp
            </anchor>
            <para>
              Big point, 1/72 inch. This length is the definition of a point in PostScript and many desktop publishing systems.
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                <indexterm index="fn" number="584" mergedindex="cp">
                  mm
                </indexterm>
                mm
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <cindex index="cp" spaces=" ">
              <indexterm index="cp" number="615">
                millimeter
              </indexterm>
            </cindex>
            <anchor name="units-of-length-mm">
              units of length mm
            </anchor>
            <para>
              Millimeter, 2.845
              <dmn>
                pt
              </dmn>
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                <indexterm index="fn" number="585" mergedindex="cp">
                  cm
                </indexterm>
                cm
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <cindex index="cp" spaces=" ">
              <indexterm index="cp" number="616">
                centimeter
              </indexterm>
            </cindex>
            <anchor name="units-of-length-cm">
              units of length cm
            </anchor>
            <para>
              Centimeter, 10
              <dmn>
                mm
              </dmn>
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                <indexterm index="fn" number="586" mergedindex="cp">
                  dd
                </indexterm>
                dd
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <cindex index="cp" spaces=" ">
              <indexterm index="cp" number="617">
                didot point
              </indexterm>
            </cindex>
            <anchor name="units-of-length-dd">
              units of length dd
            </anchor>
            <para>
              Didot point, 1.07 pt
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                <indexterm index="fn" number="587" mergedindex="cp">
                  cc
                </indexterm>
                cc
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <cindex index="cp" spaces=" ">
              <indexterm index="cp" number="618">
                cicero
              </indexterm>
            </cindex>
            <anchor name="units-of-length-cc">
              units of length cc
            </anchor>
            <para>
              Cicero, 12 dd
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                <indexterm index="fn" number="588" mergedindex="cp">
                  sp
                </indexterm>
                sp
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <cindex index="cp" spaces=" ">
              <indexterm index="cp" number="619">
                scaled point
              </indexterm>
            </cindex>
            <anchor name="units-of-length-sp">
              units of length sp
            </anchor>
            <para>
              Scaled point, 1/65536 pt
            </para>
          </tableitem>
        </tableentry>
      </ftable>
      <para>
        Three other units are defined according to the current font, rather than being an absolute dimension.
      </para>
      <ftable commandarg="code" spaces=" " endspaces=" ">
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                <indexterm index="fn" number="589" mergedindex="cp">
                  ex
                </indexterm>
                ex
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <cindex index="cp" spaces=" ">
              <indexterm index="cp" number="620">
                x-height
              </indexterm>
            </cindex>
            <cindex index="cp" spaces=" ">
              <indexterm index="cp" number="621">
                ex
              </indexterm>
            </cindex>
            <anchor name="Lengths_002fex">
              Lengths/ex
            </anchor>
            <anchor name="units-of-length-ex">
              units of length ex
            </anchor>
            <para>
              The x-height of the current font
              <dfn>
                ex
              </dfn>
              , traditionally the height of the lowercase letter x, is often used for vertical lengths.
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                <indexterm index="fn" number="590" mergedindex="cp">
                  em
                </indexterm>
                em
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <cindex index="cp" spaces=" ">
              <indexterm index="cp" number="622">
                m-width
              </indexterm>
            </cindex>
            <cindex index="cp" spaces=" ">
              <indexterm index="cp" number="623">
                em
              </indexterm>
            </cindex>
            <anchor name="Lengths_002fem">
              Lengths/em
            </anchor>
            <anchor name="units-of-length-em">
              units of length em
            </anchor>
            <para>
              Similarly
              <dfn>
                em
              </dfn>
              , traditionally the width of the capital letter M, is often used for horizontal lengths. This is also often the size of the current font, e.g., a nominal 10
              <dmn>
                pt
              </dmn>
               font will have 1
              <dmn>
                em
              </dmn>
               = 10
              <dmn>
                pt
              </dmn>
              .
Default handler: &latex;
               has several commands to produce horizontal spaces based on the em (
              <pxref label="_005censpace-_0026-_005cquad-_0026-_005cqquad">
                <xrefnodename>
                  \enspace
                  &
                   \quad
                  &
                   \qquad
                </xrefnodename>
              </pxref>
              ).
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                <indexterm index="fn" number="591" mergedindex="cp">
                  mu
                </indexterm>
                mu
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <cindex index="cp" spaces=" ">
              <indexterm index="cp" number="624">
                mu, math unit
              </indexterm>
            </cindex>
            <anchor name="units-of-length-mu">
              units of length mu
            </anchor>
            <para>
              Finally, in math mode, many definitions are expressed in terms of the math unit
              <dfn>
                mu
              </dfn>
              , defined by 1
              <dmn>
                em
              </dmn>
               = 18
              <dmn>
                mu
              </dmn>
              , where the em is taken from the current math symbols family.
              <xref label="Spacing-in-math-mode">
                <xrefnodename>
                  Spacing in math mode
                </xrefnodename>
              </xref>
              .
            </para>
          </tableitem>
        </tableentry>
      </ftable>
      <para>
        Using these units can help make a definition work better across font changes. For example, a definition of the vertical space between list items given as
        <code>
          \setlength
Default handler: &lbrace;
          \itemsep
Default handler: &rbrace;
Default handler: &lbrace;
          1ex plus 0.05ex minus 0.01ex
Default handler: &rbrace;
        </code>
         is more likely to still be reasonable if the font is changed than a definition given in points.
      </para>
    </section>
    <node name="_005csetlength" spaces=" ">
      <nodename>
        \setlength
      </nodename>
      <nodenext automatic="on">
        \addtolength
      </nodenext>
      <nodeprev automatic="on">
        Units of length
      </nodeprev>
      <nodeup automatic="on">
        Lengths
      </nodeup>
    </node>
    <section spaces=" ">
      <sectiontitle>
        <code>
          \setlength
        </code>
      </sectiontitle>
      <findex index="fn" spaces=" ">
        <indexterm index="fn" number="592" mergedindex="cp">
          \setlength
        </indexterm>
      </findex>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="625">
          lengths, setting
        </indexterm>
      </cindex>
      <para>
        Synopsis:
      </para>
      <example endspaces=" ">
        <pre xml:space="preserve">
          \setlength
Default handler: &lbrace;
          \
          <var>
            len
          </var>
Default handler: &rbrace;
Default handler: &lbrace;
          <var>
            amount
          </var>
Default handler: &rbrace;
        </pre>
      </example>
      <para>
        Set the length \
        <var>
          len
        </var>
         to
        <var>
          amount
        </var>
        . The length name
        <code>
          \
          <var>
            len
          </var>
        </code>
         has to be a control sequence (
        <pxref label="Control-sequences">
          <xrefnodename>
            Control sequences
          </xrefnodename>
        </pxref>
        ), and as such must begin with a backslash,
        <code>
          \
        </code>
         under normal circumstances. The
        <var>
          amount
        </var>
         can be a rubber length (
        <pxref label="Lengths">
          <xrefnodename>
            Lengths
          </xrefnodename>
        </pxref>
        ). It can be positive, negative or zero, and can be in any units that
Default handler: &latex;
         understands (
        <pxref label="Units-of-length">
          <xrefnodename>
            Units of length
          </xrefnodename>
        </pxref>
        ).
      </para>
      <para>
        Below, with
Default handler: &latex;
Default handler: &textrsquo;
        s defaults the first paragraph will be indented while the second will not.
      </para>
      <example endspaces=" ">
        <pre xml:space="preserve">
          I told the doctor I broke my leg in two places. \setlength
Default handler: &lbrace;
          \parindent
Default handler: &rbrace;
Default handler: &lbrace;
          0em
Default handler: &rbrace;
           He said stop going to those places.
        </pre>
      </example>
      <para>
        If you did not declare \
        <var>
          len
        </var>
         with
        <code>
          \newlength
        </code>
        , for example if you mistype it as in
        <code>
          \newlength
Default handler: &lbrace;
          \specparindent
Default handler: &rbrace;
          \setlength
Default handler: &lbrace;
          \sepcparindent
Default handler: &rbrace;
Default handler: &lbrace;
          ...
Default handler: &rbrace;
        </code>
        , then you get an error like
        <samp>
          Undefined control sequence.
          <
          argument
          >
           \sepcindent
        </samp>
        . If you omit the backslash at the start of the length name then you get an error like
        <samp>
          Missing number, treated as zero.
        </samp>
        .
      </para>
    </section>
    <node name="_005caddtolength" spaces=" ">
      <nodename>
        \addtolength
      </nodename>
      <nodenext automatic="on">
        \settodepth
      </nodenext>
      <nodeprev automatic="on">
        \setlength
      </nodeprev>
      <nodeup automatic="on">
        Lengths
      </nodeup>
    </node>
    <section spaces=" ">
      <sectiontitle>
        <code>
          \addtolength
        </code>
      </sectiontitle>
      <findex index="fn" spaces=" ">
        <indexterm index="fn" number="593" mergedindex="cp">
          \addtolength
        </indexterm>
      </findex>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="626">
          lengths, adding to
        </indexterm>
      </cindex>
      <para>
        Synopsis:
      </para>
      <example endspaces=" ">
        <pre xml:space="preserve">
          \addtolength
Default handler: &lbrace;
          \
          <var>
            len
          </var>
Default handler: &rbrace;
Default handler: &lbrace;
          <var>
            amount
          </var>
Default handler: &rbrace;
        </pre>
      </example>
      <para>
        Increment the length \
        <var>
          len
        </var>
         by
        <var>
          amount
        </var>
        . The length name
        <code>
          \
          <var>
            len
          </var>
        </code>
         has to be a control sequence (
        <pxref label="Control-sequences">
          <xrefnodename>
            Control sequences
          </xrefnodename>
        </pxref>
        ), and as such must begin with a backslash,
        <code>
          \
        </code>
         under normal circumstances. The
        <var>
          amount
        </var>
         is a rubber length (
        <pxref label="Lengths">
          <xrefnodename>
            Lengths
          </xrefnodename>
        </pxref>
        ). It can be positive, negative or zero, and can be in any units that
Default handler: &latex;
         understands (
        <pxref label="Units-of-length">
          <xrefnodename>
            Units of length
          </xrefnodename>
        </pxref>
        ).
      </para>
      <para>
        Below, if
        <code>
          \parskip
        </code>
         starts with the value
        <code>
          0pt plus 1pt
        </code>
      </para>
      <example endspaces=" ">
        <pre xml:space="preserve">
          Doctor: how is the boy who swallowed the silver dollar? \addtolength
Default handler: &lbrace;
          \parskip
Default handler: &rbrace;
Default handler: &lbrace;
          1pt
Default handler: &rbrace;
           Nurse: no change.
        </pre>
      </example>
      <noindent/>
      <para>
        then it has the value
        <code>
          1pt plus 1pt
        </code>
         for the second paragraph.
      </para>
      <para>
        If you did not declare \
        <var>
          len
        </var>
         with
        <code>
          \newlength
        </code>
        , for example if you mistype it as in
        <code>
          \newlength
Default handler: &lbrace;
          \specparindent
Default handler: &rbrace;
          \addtolength
Default handler: &lbrace;
          \sepcparindent
Default handler: &rbrace;
Default handler: &lbrace;
          ...
Default handler: &rbrace;
        </code>
        , then you get an error like
        <samp>
          Undefined control sequence.
          <
          argument
          >
           \sepcindent
        </samp>
        . If the
        <var>
          amount
        </var>
         uses some length that has not been declared, for instance if for example you mistype the above as
        <code>
          \addtolength
Default handler: &lbrace;
          \specparindent
Default handler: &rbrace;
Default handler: &lbrace;
          0.6\praindent
Default handler: &rbrace;
        </code>
        , then you get something like
        <samp>
          Undefined control sequence.
          <
          argument
          >
           \praindent
        </samp>
        . If you leave off the backslash at the start of \
        <var>
          len
        </var>
        , as in
        <code>
          \addtolength
Default handler: &lbrace;
          parindent
Default handler: &rbrace;
Default handler: &lbrace;
          1pt
Default handler: &rbrace;
        </code>
        , then you get something like
        <samp>
          You can't use `the letter p' after \advance
        </samp>
        .
      </para>
    </section>
    <node name="_005csettodepth" spaces=" ">
      <nodename>
        \settodepth
      </nodename>
      <nodenext automatic="on">
        \settoheight
      </nodenext>
      <nodeprev automatic="on">
        \addtolength
      </nodeprev>
      <nodeup automatic="on">
        Lengths
      </nodeup>
    </node>
    <section spaces=" ">
      <sectiontitle>
        <code>
          \settodepth
        </code>
      </sectiontitle>
      <findex index="fn" spaces=" ">
        <indexterm index="fn" number="594" mergedindex="cp">
          \settodepth
        </indexterm>
      </findex>
      <para>
        Synopsis:
      </para>
      <example endspaces=" ">
        <pre xml:space="preserve">
          \settodepth
Default handler: &lbrace;
          \
          <var>
            len
          </var>
Default handler: &rbrace;
Default handler: &lbrace;
          <var>
            text
          </var>
Default handler: &rbrace;
        </pre>
      </example>
      <para>
        Set the length \
        <var>
          len
        </var>
         to the depth of box that
Default handler: &latex;
         gets on typesetting the
        <var>
          text
        </var>
         argument. The length name
        <code>
          \
          <var>
            len
          </var>
        </code>
         has to be a control sequence (
        <pxref label="Control-sequences">
          <xrefnodename>
            Control sequences
          </xrefnodename>
        </pxref>
        ), and as such must begin with a backslash,
        <code>
          \
        </code>
         under normal circumstances.
      </para>
      <para>
        This will print how low the character descenders go.
      </para>
      <example endspaces=" ">
        <pre xml:space="preserve">
          \newlength
Default handler: &lbrace;
          \alphabetdepth
Default handler: &rbrace;
           \settodepth
Default handler: &lbrace;
          \alphabetdepth
Default handler: &rbrace;
Default handler: &lbrace;
          abcdefghijklmnopqrstuvwxyz
Default handler: &rbrace;
           \the\alphabetdepth
        </pre>
      </example>
      <para>
        If you did not declare \
        <var>
          len
        </var>
         with
        <code>
          \newlength
        </code>
        , if for example you mistype the above as
        <code>
          \settodepth
Default handler: &lbrace;
          \aplhabetdepth
Default handler: &rbrace;
Default handler: &lbrace;
          abc...
Default handler: &rbrace;
        </code>
        , then you get something like
        <samp>
          Undefined control sequence.
          <
          argument
          >
           \aplhabetdepth
        </samp>
        . If you leave the backslash out of \
        <var>
          len
        </var>
        , as in
        <code>
          \settodepth
Default handler: &lbrace;
          alphabetdepth
Default handler: &rbrace;
Default handler: &lbrace;
          ...
Default handler: &rbrace;
        </code>
         then you get something like
        <samp>
          Missing number, treated as zero.
          <
          to be read again
          >
           \setbox
        </samp>
        .
      </para>
    </section>
    <node name="_005csettoheight" spaces=" ">
      <nodename>
        \settoheight
      </nodename>
      <nodenext automatic="on">
        \settowidth
      </nodenext>
      <nodeprev automatic="on">
        \settodepth
      </nodeprev>
      <nodeup automatic="on">
        Lengths
      </nodeup>
    </node>
    <section spaces=" ">
      <sectiontitle>
        <code>
          \settoheight
        </code>
      </sectiontitle>
      <findex index="fn" spaces=" ">
        <indexterm index="fn" number="595" mergedindex="cp">
          \settoheight
        </indexterm>
      </findex>
      <para>
        Synopsis:
      </para>
      <example endspaces=" ">
        <pre xml:space="preserve">
          \settoheight
Default handler: &lbrace;
          \
          <var>
            len
          </var>
Default handler: &rbrace;
Default handler: &lbrace;
          text
Default handler: &rbrace;
        </pre>
      </example>
      <para>
        Sets the length \
        <var>
          len
        </var>
         to the height of box that
Default handler: &latex;
         gets on typesetting the
        <code>
          text
        </code>
         argument. The length name
        <code>
          \
          <var>
            len
          </var>
        </code>
         has to be a control sequence (
        <pxref label="Control-sequences">
          <xrefnodename>
            Control sequences
          </xrefnodename>
        </pxref>
        ), and as such must begin with a backslash,
        <code>
          \
        </code>
         under normal circumstances.
      </para>
      <para>
        This will print how high the characters go.
      </para>
      <example endspaces=" ">
        <pre xml:space="preserve">
          \newlength
Default handler: &lbrace;
          \alphabetheight
Default handler: &rbrace;
           \settoheight
Default handler: &lbrace;
          \alphabetheight
Default handler: &rbrace;
Default handler: &lbrace;
          abcdefghijklmnopqrstuvwxyz
Default handler: &rbrace;
           \the\alphabetheight
        </pre>
      </example>
      <para>
        If no such length \
        <var>
          len
        </var>
         has been declared with
        <code>
          \newlength
        </code>
        , if for example you mistype as
        <code>
          \settoheight
Default handler: &lbrace;
          \aplhabetheight
Default handler: &rbrace;
Default handler: &lbrace;
          abc...
Default handler: &rbrace;
        </code>
        , then you get something like
        <samp>
          Undefined control sequence.
          <
          argument
          >
           \alphabetheight
        </samp>
        . If you leave the backslash out of \
        <var>
          len
        </var>
        , as in
        <code>
          \settoheight
Default handler: &lbrace;
          alphabetheight
Default handler: &rbrace;
Default handler: &lbrace;
          ...
Default handler: &rbrace;
        </code>
         then you get something like
        <samp>
          Missing number, treated as zero.
          <
          to be read again
          >
           \setbox
        </samp>
        .
      </para>
    </section>
    <node name="_005csettowidth" spaces=" ">
      <nodename>
        \settowidth
      </nodename>
      <nodenext automatic="on">
        \stretch
      </nodenext>
      <nodeprev automatic="on">
        \settoheight
      </nodeprev>
      <nodeup automatic="on">
        Lengths
      </nodeup>
    </node>
    <section spaces=" ">
      <sectiontitle>
        <code>
          \settowidth
        </code>
      </sectiontitle>
      <findex index="fn" spaces=" ">
        <indexterm index="fn" number="596" mergedindex="cp">
          \settowidth
        </indexterm>
      </findex>
      <para>
        Synopsis:
      </para>
      <example endspaces=" ">
        <pre xml:space="preserve">
          \settowidth
Default handler: &lbrace;
          \
          <var>
            len
          </var>
Default handler: &rbrace;
Default handler: &lbrace;
          <var>
            text
          </var>
Default handler: &rbrace;
        </pre>
      </example>
      <para>
        Set the length \
        <var>
          len
        </var>
         to the width of the box that
Default handler: &latex;
         gets on typesetting the
        <var>
          text
        </var>
         argument. The length name
        <code>
          \
          <var>
            len
          </var>
        </code>
         has to be a control sequence (
        <pxref label="Control-sequences">
          <xrefnodename>
            Control sequences
          </xrefnodename>
        </pxref>
        ), and as such must begin with a backslash,
        <code>
          \
        </code>
         under normal circumstances.
      </para>
      <para>
        This prints the width of the lowercase ASCII alphabet.
      </para>
      <example endspaces=" ">
        <pre xml:space="preserve">
          \newlength
Default handler: &lbrace;
          \alphabetwidth
Default handler: &rbrace;
           \settowidth
Default handler: &lbrace;
          \alphabetwidth
Default handler: &rbrace;
Default handler: &lbrace;
          abcdefghijklmnopqrstuvwxyz
Default handler: &rbrace;
           \the\alphabetwidth
        </pre>
      </example>
      <para>
        If no such length \
        <var>
          len
        </var>
         has been declared with
        <code>
          \newlength
        </code>
        , if for example you mistype the above as
        <code>
          \settowidth
Default handler: &lbrace;
          \aplhabetwidth
Default handler: &rbrace;
Default handler: &lbrace;
          abc...
Default handler: &rbrace;
        </code>
        , then you get something like
        <samp>
          Undefined control sequence.
          <
          argument
          >
           \aplhabetwidth
        </samp>
        . If you leave the backslash out of \
        <var>
          len
        </var>
        , as in
        <code>
          \settoheight
Default handler: &lbrace;
          alphabetwidth
Default handler: &rbrace;
Default handler: &lbrace;
          ...
Default handler: &rbrace;
        </code>
         then you get something like
        <samp>
          Missing number, treated as zero.
          <
          to be read again
          >
           \setbox
        </samp>
        .
      </para>
    </section>
    <node name="_005cstretch" spaces=" ">
      <nodename>
        \stretch
      </nodename>
      <nodenext automatic="on">
        Expressions
      </nodenext>
      <nodeprev automatic="on">
        \settowidth
      </nodeprev>
      <nodeup automatic="on">
        Lengths
      </nodeup>
    </node>
    <section spaces=" ">
      <sectiontitle>
        <code>
          \stretch
        </code>
      </sectiontitle>
      <findex index="fn" spaces=" ">
        <indexterm index="fn" number="597" mergedindex="cp">
          \stretch
        </indexterm>
      </findex>
      <para>
        Synopsis:
      </para>
      <example endspaces=" ">
        <pre xml:space="preserve">
          \stretch
Default handler: &lbrace;
          <var>
            number
          </var>
Default handler: &rbrace;
        </pre>
      </example>
      <para>
        Produces a rubber length with zero natural length and
        <var>
          number
        </var>
         times
        <code>
          \fill
        </code>
         units of stretchability (
        <pxref label="Lengths">
          <xrefnodename>
            Lengths
          </xrefnodename>
        </pxref>
        ). The
        <var>
          number
        </var>
         can be positive or negative. This command is robust (
        <pxref label="_005cprotect">
          <xrefnodename>
            \protect
          </xrefnodename>
        </pxref>
        ).
      </para>
      <para>
        It works for both vertical and horizontal spacing. In this horizontal example,
Default handler: &latex;
         produces three tick marks, and the distance between the first and second is half again as long as the distance between the second and third.
      </para>
      <example endspaces=" ">
        <pre xml:space="preserve">
          \rule
Default handler: &lbrace;
          0.4pt
Default handler: &rbrace;
Default handler: &lbrace;
          1ex
Default handler: &rbrace;
          \hspace
Default handler: &lbrace;
          \stretch
Default handler: &lbrace;
          1.5
Default handler: &rbrace;
Default handler: &rbrace;
          % \rule
Default handler: &lbrace;
          0.4pt
Default handler: &rbrace;
Default handler: &lbrace;
          1ex
Default handler: &rbrace;
          \hspace
Default handler: &lbrace;
          \stretch
Default handler: &lbrace;
          1
Default handler: &rbrace;
Default handler: &rbrace;
          % \rule
Default handler: &lbrace;
          0.4pt
Default handler: &rbrace;
Default handler: &lbrace;
          1ex
Default handler: &rbrace;
        </pre>
      </example>
      <para>
        In this vertical example, the
        <samp>
          We dedicate
Default handler: &dots;
        </samp>
         will have three times as much space under it as above it.
      </para>
      <example endspaces=" ">
        <pre xml:space="preserve">
          \newenvironment
Default handler: &lbrace;
          dedication
Default handler: &rbrace;
Default handler: &lbrace;
          % in document preamble \clearpage\thispagestyle
Default handler: &lbrace;
          empty
Default handler: &rbrace;
          % \vspace*
Default handler: &lbrace;
          \stretch
Default handler: &lbrace;
          1
Default handler: &rbrace;
Default handler: &rbrace;
           % stretchable space at top \it
Default handler: &rbrace;
Default handler: &lbrace;
          % \vspace
Default handler: &lbrace;
          \stretch
Default handler: &lbrace;
          3
Default handler: &rbrace;
Default handler: &rbrace;
           % space at bot is 3x as at top \clearpage
Default handler: &rbrace;
           ... \begin
Default handler: &lbrace;
          dedication
Default handler: &rbrace;
           % in document body We dedicate this book to our wives. \end
Default handler: &lbrace;
          dedication
Default handler: &rbrace;
        </pre>
      </example>
    </section>
    <node name="Expressions" spaces=" ">
      <nodename>
        Expressions
      </nodename>
      <nodeprev automatic="on">
        \stretch
      </nodeprev>
      <nodeup automatic="on">
        Lengths
      </nodeup>
    </node>
    <section spaces=" ">
      <sectiontitle>
        Expressions
      </sectiontitle>
      <findex index="fn" spaces=" ">
        <indexterm index="fn" number="598" mergedindex="cp">
          expressions
        </indexterm>
      </findex>
Default handler: <!-- c Much from Joseph Wright's https://tex.stackexchange.com/a/245663/339 -->
      <para>
        Synopsis, one of:
      </para>
      <example endspaces=" ">
        <pre xml:space="preserve">
          \numexpr
          <var>
            expression
          </var>
           \dimexpr
          <var>
            expression
          </var>
           \glueexpr
          <var>
            expression
          </var>
           \muglue
          <var>
            expression
          </var>
        </pre>
      </example>
      <para>
        Any place where you may write an integer, or a
Default handler: &tex;
         dimen, or
Default handler: &tex;
         glue, or muglue, you can instead write an expression to compute that type of quantity.
      </para>
      <para>
        An example is that
        <code>
          \the\dimexpr\linewidth-4pt\relax
        </code>
         will produce as output the length that is four points less than width of a line (the only purpose of
        <code>
          \the
        </code>
         is to show the result in the document). Analogously,
        <code>
          \romannumeral\numexpr6+3\relax
        </code>
         will produce
        <samp>
          ix
        </samp>
        , and
        <code>
          \the\glueexpr 5pt plus 1pt * 2 \relax
        </code>
         will produce
        <samp>
          10.0pt plus 2.0pt
        </samp>
        .
      </para>
      <para>
        A convenience here over doing calculations by allocating registers and then using
        <code>
          \advance
        </code>
        , etc., is that the evaluation of expressions does not involve assignments and can therefore be performed in places where assignments are not allowed. The next example computes the width of the
        <code>
          \parbox
        </code>
        .
      </para>
      <example endspaces=" ">
        <pre xml:space="preserve">
          \newlength
Default handler: &lbrace;
          \offset
Default handler: &rbrace;
          \setlength
Default handler: &lbrace;
          \offset
Default handler: &rbrace;
Default handler: &lbrace;
          2em
Default handler: &rbrace;
           \begin
Default handler: &lbrace;
          center
Default handler: &rbrace;
           \parbox
Default handler: &lbrace;
          \dimexpr\linewidth-\offset*3
Default handler: &rbrace;
Default handler: &lbrace;
          With malice toward none with charity for all with firmness in the right as God gives us to see the right let us strive on to finish the work we are in to bind up the nation's wounds, to care for him who shall have borne the battle and for his widow and his orphan \textasciitilde\ to do all which may achieve and cherish a just and lasting peace among ourselves and with all nations. ---Abraham Lincoln, Second Inaugural Address, from the memorial
Default handler: &rbrace;
           \end
Default handler: &lbrace;
          center
Default handler: &rbrace;
        </pre>
      </example>
      <para>
        The
        <var>
          expression
        </var>
         consists of one or more terms of the same type (integer, dimension, etc.) that are added or subtracted. A term that is a type of number, dimension, etc., consists of a factor of that type, optionally multiplied or divided by factors. A factor of a type is either a quantity of that type or a parenthesized subexpression. The expression produces a result of the given type, so that
        <code>
          \numexpr
        </code>
         produces an integer,
        <code>
          \dimexpr
        </code>
         produces a dimension, etc.
      </para>
      <para>
        In the quotation example above, changing to
        <code>
          \dimexpr\linewidth-3*\offset
        </code>
         gives the error
        <code>
          Illegal unit of measure (pt inserted)
        </code>
        . This is because for
        <code>
          \dimexpr
        </code>
         and
        <code>
          \glueexpr
        </code>
        , the input consists of a dimension or glue value followed by an optional multiplication factor, and not the other way around. Thus
        <code>
          \the\dimexpr 1pt*10\relax
        </code>
         is valid and produces
        <samp>
          10.0pt
        </samp>
        , but
        <code>
          \the\dimexpr 10*1pt\relax
        </code>
         gives the
        <code>
          Illegal unit
        </code>
         error.
      </para>
      <para>
        The expressions absorb tokens and carry out appropriate mathematics up to a
        <code>
          \relax
        </code>
         (which will be absorbed), or up to the first non-valid token. Thus,
        <code>
          \the\numexpr2+3px
        </code>
         will print
        <samp>
          5px
        </samp>
        , because
Default handler: &latex;
         reads the
        <code>
          \numexpr2+3
        </code>
        , which is made up of numbers, and then finds the letter
        <code>
          p
        </code>
        , which cannot be part of a number. It therefore terminates the expression and produces the
        <samp>
          5
        </samp>
        , followed by the regular text
        <samp>
          px
        </samp>
        .
      </para>
      <para>
        This termination behavior is useful in comparisons. In
        <code>
          \ifnum\numexpr\parindent*2
          <
           10pt Yes\else No\fi
        </code>
        , the less than sign terminates the expression and the result is
        <samp>
          No
        </samp>
         (in a standard
Default handler: &latex;
         article).
      </para>
      <para>
        Expressions may use the operators
        <code>
          +
        </code>
        ,
        <code>
          -
        </code>
        ,
        <code>
          *
        </code>
         and
        <code>
          /
        </code>
         along with parentheses for subexpressions,
        <code>
          (...)
        </code>
        . In glue expressions the
        <code>
          plus
        </code>
         and
        <code>
          minus
        </code>
         parts do not need parentheses to be affected by a factor. So
        <code>
          \the\glueexpr 5pt plus 1pt * 2 \relax
        </code>
         results in
        <samp>
          10pt plus 2pt
        </samp>
        .
      </para>
      <paraDefault handler: &tex;
>
         will coerce other numerical types in the same way as it does when doing register assignment. Thus
        <code>
          \the\numexpr\dimexpr 1pt\relax\relax
        </code>
         will result in
        <samp>
          65536
        </samp>
        , which is
        <code>
          1pt
        </code>
         converted to scaled points (
        <pxref label="units-of-length-sp">
          <xrefnodename>
            units of length sp
          </xrefnodename>
          <xrefinfoname>
            <code>
              sp
            </code>
          </xrefinfoname>
        </pxref>
        ,
Default handler: &tex;
Default handler: &textrsquo;
        s internal unit) and then coerced into an integer. With a
        <code>
          \glueexpr
        </code>
         here, the stretch and shrink would be dropped. Going the other way, a
        <code>
          \numexpr
        </code>
         inside a
        <code>
          \dimexpr
        </code>
         or
        <code>
          \glueexpr
        </code>
         will need appropriate units, as in
        <code>
          \the\dimexpr\numexpr 1 + 2\relax pt\relax
        </code>
        , which produces
        <samp>
          3.0pt
        </samp>
        .
      </para>
      <para>
        The details of the arithmetic: each factor is checked to be in the allowed range, numbers must be less than
        <math>
          2^{31}
        </math>
         in absolute value, and dimensions or glue components must be less than
        <math>
          2^{14}
        </math>
         points, or
        <code>
          mu
        </code>
        , or
        <code>
          fil
        </code>
        , etc. The arithmetic operations are performed individually, except for a scaling operation (a multiplication immediately followed by a division) which is done as one combined operation with a 64-bit product as intermediate value. The result of each operation is again checked to be in the allowed range.
      </para>
      <para>
        Finally, division and scaling take place with rounding (unlike
Default handler: &tex;
Default handler: &textrsquo;
        s
        <code>
          \divide
        </code>
        , which truncates). Thus
        <code>
          \the\dimexpr 5pt*(3/2)\relax
        </code>
         puts
        <samp>
          10.0pt
        </samp>
         in the document, because it rounds
        <code>
          3/2
        </code>
         to
        <code>
          2
        </code>
        , while
        <code>
          \the\dimexpr 5pt*(4/3)\relax
        </code>
         produces
        <samp>
          5.0pt
        </samp>
        .
      </para>
    </section>
  </chapter>
  <node name="Making-paragraphs" spaces=" ">
    <nodename>
      Making paragraphs
    </nodename>
    <nodenext automatic="on">
      Math formulas
    </nodenext>
    <nodeprev automatic="on">
      Lengths
    </nodeprev>
    <nodeup automatic="on">
      Top
    </nodeup>
  </node>
  <chapter spaces=" ">
    <sectiontitle>
      Making paragraphs
    </sectiontitle>
    <cindex index="cp" spaces=" ">
      <indexterm index="cp" number="627">
        making paragraphs
      </indexterm>
    </cindex>
    <cindex index="cp" spaces=" ">
      <indexterm index="cp" number="628">
        paragraphs
      </indexterm>
    </cindex>
    <para>
      To start a paragraph, just type some text. To end the current paragraph, put an empty line. This is three paragraphs, the separation of which is made by two empty lines.
    </para>
    <example endspaces=" ">
      <pre xml:space="preserve">
        It is a truth universally acknowledged, that a single man in possession of a good fortune, must be in want of a wife. However little known the feelings or views of such a man may be on his first entering a neighbourhood, this truth is so well fixed in the minds of the surrounding families, that he is considered the rightful property of some one or other of their daughters. ``My dear Mr. Bennet,'' said his lady to him one day, ``have you heard that Netherfield Park is let at last?''
      </pre>
    </example>
    <para>
      A paragraph separator can be made of a sequence of at least one blank line, at least one of which is not terminated by a comment. A blank line is a line that is empty or made only of blank characters such as space or tab. Comments in source code are started with a
      <code>
        %
      </code>
       and span up to the end of line. In the following example the two columns are identical:
    </para>
    <example endspaces=" ">
      <pre xml:space="preserve">
        \documentclass[twocolumn]
Default handler: &lbrace;
        article
Default handler: &rbrace;
         \begin
Default handler: &lbrace;
        document
Default handler: &rbrace;
         First paragraph. Second paragraph. \newpage First paragraph. % separator lines may contain blank characters. Second paragraph. \end
Default handler: &lbrace;
        document
Default handler: &rbrace;
      </pre>
    </example>
    <para>
      Once
Default handler: &latex;
       has gathered all of a paragraph
Default handler: &textrsquo;
      s contents it divides that content into lines in a way that is optimized over the entire paragraph (
      <pxref label="Line-breaking">
        <xrefnodename>
          Line breaking
        </xrefnodename>
      </pxref>
      ).
    </para>
    <para>
      There are places where a new paragraph is not permitted. Don
Default handler: &textrsquo;
      t put a blank line in math mode (
      <pxref label="Modes">
        <xrefnodename>
          Modes
        </xrefnodename>
      </pxref>
      ); here the blank line before the
      <code>
        \end
Default handler: &lbrace;
        equation
Default handler: &rbrace;
      </code>
    </para>
    <example endspaces=" ">
      <pre xml:space="preserve">
        \begin
Default handler: &lbrace;
        equation
Default handler: &rbrace;
         2^
Default handler: &lbrace;
        |S|
Default handler: &rbrace;
        >
         |S| \end
Default handler: &lbrace;
        equation
Default handler: &rbrace;
      </pre>
    </example>
    <noindent/>
    <para>
      will get you the error
      <samp>
        Missing $ inserted
      </samp>
      . Similarly, the blank line in this
      <code>
        \section
      </code>
       argument
    </para>
    <example endspaces=" ">
      <pre xml:space="preserve">
        \section
Default handler: &lbrace;
        aaa bbb
Default handler: &rbrace;
      </pre>
    </example>
    <noindent/>
    <para>
      gets
      <samp>
        Runaway argument?
Default handler: &lbrace;
        aaa ! Paragraph ended before \
Default handler: &arobase;
        sect was complete
      </samp>
      .
    </para>
    <menu endspaces=" ">
      <menuentry>
        <menuleadingtext>
          *
        </menuleadingtext>
        <menunode>
          \par
        </menunode>
        <menuseparator>
          ::
        </menuseparator>
        <menudescription>
          <pre xml:space="preserve">
            End the current paragraph.
          </pre>
        </menudescription>
      </menuentry>
      <menuentry>
        <menuleadingtext>
          *
        </menuleadingtext>
        <menunode>
          \indent
          &
           \noindent
        </menunode>
        <menuseparator>
          ::
        </menuseparator>
        <menudescription>
          <pre xml:space="preserve">
            Go into horizontal mode, possibly with an indent.
          </pre>
        </menudescription>
      </menuentry>
      <menuentry>
        <menuleadingtext>
          *
        </menuleadingtext>
        <menunode>
          \parindent
          &
           \parskip
        </menunode>
        <menuseparator>
          ::
        </menuseparator>
        <menudescription>
          <pre xml:space="preserve">
            Space added before paragraphs.
          </pre>
        </menudescription>
      </menuentry>
      <menuentry>
        <menuleadingtext>
          *
        </menuleadingtext>
        <menunode>
          Marginal notes
        </menunode>
        <menuseparator>
          ::
        </menuseparator>
        <menudescription>
          <pre xml:space="preserve">
            Put remarks in the margin.
          </pre>
        </menudescription>
      </menuentry>
    </menu>
    <node name="_005cpar" spaces=" ">
      <nodename>
        \par
      </nodename>
      <nodenext automatic="on">
        \indent
        &
         \noindent
      </nodenext>
      <nodeup automatic="on">
        Making paragraphs
      </nodeup>
    </node>
    <section spaces=" ">
      <sectiontitle>
        <code>
          \par
        </code>
      </sectiontitle>
      <findex index="fn" spaces=" ">
        <indexterm index="fn" number="599" mergedindex="cp">
          \par
        </indexterm>
      </findex>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="629">
          paragraph, ending
        </indexterm>
      </cindex>
      <para>
        Synopsis (note that while reading the input
Default handler: &tex;
         converts any sequence of one or more blank lines to a
        <code>
          \par
        </code>
        ,
        <ref label="Making-paragraphs">
          <xrefnodename>
            Making paragraphs
          </xrefnodename>
        </ref>
        ):
      </para>
      <example endspaces=" ">
        <pre xml:space="preserve">
          \par
        </pre>
      </example>
      <para>
        End the current paragraph. The usual way to separate paragraphs is with a blank line but the
        <code>
          \par
        </code>
         command is entirely equivalent. This command is robust (
        <pxref label="_005cprotect">
          <xrefnodename>
            \protect
          </xrefnodename>
        </pxref>
        ).
      </para>
      <para>
        This example uses
        <code>
          \par
        </code>
         rather than a blank line simply for readability.
      </para>
      <example endspaces=" ">
        <pre xml:space="preserve">
          \newcommand
Default handler: &lbrace;
          \syllabusLegalese
Default handler: &rbrace;
Default handler: &lbrace;
          % \whatCheatingIs\par\whatHappensWhenICatchYou
Default handler: &rbrace;
        </pre>
      </example>
      <para>
        In LR mode the
        <code>
          \par
        </code>
         command does nothing and is ignored. In paragraph mode, the
        <code>
          \par
        </code>
         command terminates paragraph mode, switching
Default handler: &latex;
         to vertical mode (
        <pxref label="Modes">
          <xrefnodename>
            Modes
          </xrefnodename>
        </pxref>
        ).
      </para>
      <para>
        You cannot use the
        <code>
          \par
        </code>
         command in a math mode. You also cannot use it in the argument of many commands, such as the sectioning commands, e.g.
Default handler: &noeos;
        <code>
          \section
        </code>
         (
        <pxref label="Making-paragraphs">
          <xrefnodename>
            Making paragraphs
          </xrefnodename>
        </pxref>
         and
        <ref label="_005cnewcommand-_0026-_005crenewcommand">
          <xrefnodename>
            \newcommand
            &
             \renewcommand
          </xrefnodename>
        </ref>
        ).
      </para>
      <para>
        The
        <code>
          \par
        </code>
         command is not the same as the
        <code>
          \paragraph
        </code>
         command. The latter is, like
        <code>
          \section
        </code>
         or
        <code>
          \subsection
        </code>
        , a sectioning command used by the
Default handler: &latex;
         document standard classes (
        <pxref label="_005csubsubsection-_0026-_005cparagraph-_0026-_005csubparagraph">
          <xrefnodename>
            \subsubsection
            &
             \paragraph
            &
             \subparagraph
          </xrefnodename>
        </pxref>
        ).
      </para>
      <para>
        The
        <code>
          \par
        </code>
         command is not the same as
        <code>
          \newline
        </code>
         or the line break double backslash,
        <code>
          \\
        </code>
        . The difference is that
        <code>
          \par
        </code>
         ends the paragraph, not just the line, and also triggers the addition of the between-paragraph vertical space
        <code>
          \parskip
        </code>
         (
        <pxref label="_005cparindent-_0026-_005cparskip">
          <xrefnodename>
            \parindent
            &
             \parskip
          </xrefnodename>
        </pxref>
        ).
      </para>
      <para>
        The output from this example
      </para>
      <example endspaces=" ">
        <pre xml:space="preserve">
          xyz \setlength
Default handler: &lbrace;
          \parindent
Default handler: &rbrace;
Default handler: &lbrace;
          3in
Default handler: &rbrace;
           \setlength
Default handler: &lbrace;
          \parskip
Default handler: &rbrace;
Default handler: &lbrace;
          5in
Default handler: &rbrace;
           \noindent test\indent test1\par test2
        </pre>
      </example>
      <noindent/>
      <para>
        is: after
        <samp>
          xyz
        </samp>
         there is a vertical skip of 5
Default handler: &nbsp;
        inches and then
        <samp>
          test
        </samp>
         appears, aligned with the left margin. On the same line, there is an empty horizontal space of 3
Default handler: &nbsp;
        inches and then
        <samp>
          test1
        </samp>
         appears. Finally. there is a vertical space of 5
Default handler: &nbsp;
        inches, followed by a fresh paragraph with a paragraph indent of 3
Default handler: &nbsp;
        inches, and then
Default handler: &latex;
         puts the text
        <samp>
          test2
        </samp>
        .
      </para>
    </section>
    <node name="_005cindent-_0026-_005cnoindent" spaces=" ">
      <nodename>
        \indent
        &
         \noindent
      </nodename>
      <nodenext automatic="on">
        \parindent
        &
         \parskip
      </nodenext>
      <nodeprev automatic="on">
        \par
      </nodeprev>
      <nodeup automatic="on">
        Making paragraphs
      </nodeup>
    </node>
    <section spaces=" ">
      <sectiontitle>
        <code>
          \indent
        </code>
        &
        <code>
          \noindent
        </code>
      </sectiontitle>
      <anchor name="_005cindent">
        \indent
      </anchor>
      <anchor name="_005cnoindent">
        \noindent
      </anchor>
      <findex index="fn" spaces=" ">
        <indexterm index="fn" number="600" mergedindex="cp">
          \indent
        </indexterm>
      </findex>
      <findex index="fn" spaces=" ">
        <indexterm index="fn" number="601" mergedindex="cp">
          \noindent
        </indexterm>
      </findex>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="630">
          indent, forcing
        </indexterm>
      </cindex>
      <para>
        Synopsis:
      </para>
      <example endspaces=" ">
        <pre xml:space="preserve">
          \indent
        </pre>
      </example>
      <noindent/>
      <para>
        or
      </para>
      <example endspaces=" ">
        <pre xml:space="preserve">
          \noindent
        </pre>
      </example>
      <para>
        Go into horizontal mode (
        <pxref label="Modes">
          <xrefnodename>
            Modes
          </xrefnodename>
        </pxref>
        ). The
        <code>
          \indent
        </code>
         command first outputs an empty box whose width is
        <code>
          \parindent
        </code>
        . These commands are robust (
        <pxref label="_005cprotect">
          <xrefnodename>
            \protect
          </xrefnodename>
        </pxref>
        ).
      </para>
      <para>
        Ordinarily you create a new paragraph by putting in a blank line.
        <xref label="_005cpar">
          <xrefnodename>
            \par
          </xrefnodename>
        </xref>
        , for the difference between this command and
        <code>
          \par
        </code>
        . To start a paragraph without an indent, or to continue an interrupted paragraph, use
        <code>
          \noindent
        </code>
        .
      </para>
      <para>
        In the middle of a paragraph the
        <code>
          \noindent
        </code>
         command has no effect, because
Default handler: &latex;
         is already in horizontal mode there. The
        <code>
          \indent
        </code>
         command
Default handler: &textrsquo;
        s only effect is to output a space.
      </para>
      <para>
        This example starts a fresh paragraph.
      </para>
      <example endspaces=" ">
        <pre xml:space="preserve">
          ... end of the prior paragraph. \noindent This paragraph is not indented.
        </pre>
      </example>
      <noindent/>
      <para>
        and this continues an interrupted paragraph.
      </para>
      <example endspaces=" ">
        <pre xml:space="preserve">
          The data \begin
Default handler: &lbrace;
          center
Default handler: &rbrace;
           \begin
Default handler: &lbrace;
          tabular
Default handler: &rbrace;
Default handler: &lbrace;
          rl
Default handler: &rbrace;
           ... \end
Default handler: &lbrace;
          tabular
Default handler: &rbrace;
           \end
Default handler: &lbrace;
          center
Default handler: &rbrace;
           \noindent shows this clearly.
        </pre>
      </example>
      <findex index="fn" spaces=" ">
        <indexterm index="fn" number="602" mergedindex="cp">
          \parindent
        </indexterm>
      </findex>
      <para>
        To omit indentation in the entire document put
        <code>
          \setlength
Default handler: &lbrace;
          \parindent
Default handler: &rbrace;
Default handler: &lbrace;
          0pt
Default handler: &rbrace;
        </code>
         in the preamble. If you do that, you may want to also set the length of spaces between paragraphs,
        <code>
          \parskip
        </code>
         (
        <pxref label="_005cparindent-_0026-_005cparskip">
          <xrefnodename>
            \parindent
            &
             \parskip
          </xrefnodename>
        </pxref>
        ).
      </para>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="631">
          <r>
            package
          </r>
          ,
          <code>
            indentfirst
          </code>
        </indexterm>
      </cindex>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="632">
          <code>
            indentfirst
          </code>
          <r>
            package
          </r>
        </indexterm>
      </cindex>
      <para>
        Default
Default handler: &latex;
         styles have the first paragraph after a section that is not indented, as is traditional typesetting in English. To change that, look on CTAN for the package
        <code>
          indentfirst
        </code>
        .
      </para>
    </section>
    <node name="_005cparindent-_0026-_005cparskip" spaces=" ">
      <nodename>
        \parindent
        &
         \parskip
      </nodename>
      <nodenext automatic="on">
        Marginal notes
      </nodenext>
      <nodeprev automatic="on">
        \indent
        &
         \noindent
      </nodeprev>
      <nodeup automatic="on">
        Making paragraphs
      </nodeup>
    </node>
    <section spaces=" ">
      <sectiontitle>
        <code>
          \parindent
        </code>
        &
        <code>
          \parskip
        </code>
      </sectiontitle>
      <anchor name="_005cparindent">
        \parindent
      </anchor>
      <anchor name="_005cparskip">
        \parskip
      </anchor>
      <findex index="fn" spaces=" ">
        <indexterm index="fn" number="603" mergedindex="cp">
          \parindent
        </indexterm>
      </findex>
      <findex index="fn" spaces=" ">
        <indexterm index="fn" number="604" mergedindex="cp">
          \parskip
        </indexterm>
      </findex>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="633">
          paragraph indentation
        </indexterm>
      </cindex>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="634">
          horizontal paragraph indentation
        </indexterm>
      </cindex>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="635">
          vertical space before paragraphs
        </indexterm>
      </cindex>
      <para>
        Synopsis:
      </para>
      <example endspaces=" ">
        <pre xml:space="preserve">
          \setlength
Default handler: &lbrace;
          \parindent
Default handler: &rbrace;
Default handler: &lbrace;
          <var>
            horizontal len
          </var>
Default handler: &rbrace;
           \setlength
Default handler: &lbrace;
          \parskip
Default handler: &rbrace;
Default handler: &lbrace;
          <var>
            vertical len
          </var>
Default handler: &rbrace;
        </pre>
      </example>
      <para>
        Both are rubber lengths (
        <pxref label="Lengths">
          <xrefnodename>
            Lengths
          </xrefnodename>
        </pxref>
        ). They affect the indentation of ordinary paragraphs, not paragraphs inside minipages (
        <pxref label="minipage">
          <xrefnodename>
            minipage
          </xrefnodename>
        </pxref>
        ), and the vertical space between paragraphs, respectively.
      </para>
      <para>
        For example, if this is put in the preamble:
      </para>
      <example endspaces=" ">
        <pre xml:space="preserve">
          \setlength
Default handler: &lbrace;
          \parindent
Default handler: &rbrace;
Default handler: &lbrace;
          0em
Default handler: &rbrace;
           \setlength
Default handler: &lbrace;
          \parskip
Default handler: &rbrace;
Default handler: &lbrace;
          1ex
Default handler: &rbrace;
        </pre>
      </example>
      <noindent/>
      <para>
        The document will have paragraphs that are not indented, but instead are vertically separated by about the height of a lowercase
        <samp>
          x
        </samp>
        .
      </para>
      <para>
        In
Default handler: &latex;
         standard class documents, the default value for
        <code>
          \parindent
        </code>
         in one-column documents is
        <code>
          15pt
        </code>
         when the default text size is
        <code>
          10pt
        </code>
        ,
        <code>
          17pt
        </code>
         for
        <code>
          11pt
        </code>
        , and
        <code>
          1.5em
        </code>
         for
        <code>
          12pt
        </code>
        . In two-column documents it is
        <code>
          1em
        </code>
        . (These values are set before
Default handler: &latex;
         calls
        <code>
          \normalfont
        </code>
         so
        <code>
          em
        </code>
         is derived from the default font, Computer Modern. If you use a different font then to set
        <code>
          \parindent
        </code>
         to 1
        <dmn>
          em
        </dmn>
         matching that font, put
        <code>
          \AtBeginDocument
Default handler: &lbrace;
          \setlength
Default handler: &lbrace;
          \parindent
Default handler: &rbrace;
Default handler: &lbrace;
          1em
Default handler: &rbrace;
Default handler: &rbrace;
        </code>
         in the preamble.)
      </para>
      <para>
        The default value for
        <code>
          \parskip
        </code>
         in
Default handler: &latex;
Default handler: &textrsquo;
        s standard document classes is
        <code>
          0pt plus1pt
        </code>
        .
      </para>
    </section>
    <node name="Marginal-notes" spaces=" ">
      <nodename>
        Marginal notes
      </nodename>
      <nodeprev automatic="on">
        \parindent
        &
         \parskip
      </nodeprev>
      <nodeup automatic="on">
        Making paragraphs
      </nodeup>
    </node>
    <section spaces=" ">
      <sectiontitle>
        Marginal notes
      </sectiontitle>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="636">
          marginal notes
        </indexterm>
      </cindex>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="637">
          notes in the margin
        </indexterm>
      </cindex>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="638">
          remarks in the margin
        </indexterm>
      </cindex>
      <findex index="fn" spaces=" ">
        <indexterm index="fn" number="605" mergedindex="cp">
          \marginpar
        </indexterm>
      </findex>
      <para>
        Synopsis, one of:
      </para>
      <example endspaces=" ">
        <pre xml:space="preserve">
          \marginpar
Default handler: &lbrace;
          <var>
            right
          </var>
Default handler: &rbrace;
           \marginpar[
          <var>
            left
          </var>
          ]
Default handler: &lbrace;
          <var>
            right
          </var>
Default handler: &rbrace;
        </pre>
      </example>
      <para>
        Create a note in the margin. The first line of the note will have the same baseline as the line in the text where the
        <code>
          \marginpar
        </code>
         occurs.
      </para>
      <para>
        The margin that
Default handler: &latex;
         uses for the note depends on the current layout (
        <pxref label="Document-class-options">
          <xrefnodename>
            Document class options
          </xrefnodename>
        </pxref>
        ) and also on
        <code>
          \reversemarginpar
        </code>
         (see below). If you are using one-sided layout (document option
        <code>
          oneside
        </code>
        ) then it goes in the right margin. If you are using two-sided layout (document option
        <code>
          twoside
        </code>
        ) then it goes in the outside margin. If you are in two-column layout (document option
        <code>
          twocolumn
        </code>
        ) then it goes in the nearest margin.
      </para>
      <findex index="fn" spaces=" ">
        <indexterm index="fn" number="606" mergedindex="cp">
          \reversemarginpar
        </indexterm>
      </findex>
      <findex index="fn" spaces=" ">
        <indexterm index="fn" number="607" mergedindex="cp">
          \normalmarginpar
        </indexterm>
      </findex>
      <para>
        If you declare
        <code>
          \reversemarginpar
        </code>
         then
Default handler: &latex;
         will place subsequent marginal notes in the opposite margin to that given in the prior paragraph. Revert that to the default position with
        <code>
          \normalmarginpar
        </code>
        .
      </para>
      <para>
        When you specify the optional argument
        <var>
          left
        </var>
         then it is used for a note in the left margin, while the mandatory argument
        <var>
          right
        </var>
         is used for a note in the right margin.
      </para>
      <para>
        Normally, a note
Default handler: &textrsquo;
        s first word will not be hyphenated. You can enable hyphenation there by beginning
        <var>
          left
        </var>
         or
        <var>
          right
        </var>
         with
        <code>
          \hspace
Default handler: &lbrace;
          0pt
Default handler: &rbrace;
        </code>
        .
      </para>
      <para>
        These parameters affect the formatting of the note:
      </para>
      <ftable commandarg="code" spaces=" " endspaces=" ">
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                <indexterm index="fn" number="608" mergedindex="cp">
                  \marginparpush
                </indexterm>
                \marginparpush
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <anchor name="marginal-notes-marginparpush">
              marginal notes marginparpush
            </anchor>
            <para>
              Minimum vertical space between notes; default
              <samp>
                7pt
              </samp>
               for
              <samp>
                12pt
              </samp>
               documents,
              <samp>
                5pt
              </samp>
               else. See also
Default handler: &nbsp;
              <ref label="page-layout-parameters-marginparpush">
                <xrefnodename>
                  page layout parameters marginparpush
                </xrefnodename>
              </ref>
              .
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                <indexterm index="fn" number="609" mergedindex="cp">
                  \marginparsep
                </indexterm>
                \marginparsep
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <anchor name="marginal-notes-marginparsep">
              marginal notes marginparsep
            </anchor>
            <para>
              Horizontal space between the main text and the note; default
              <samp>
                11pt
              </samp>
               for
              <samp>
                10pt
              </samp>
               documents,
              <samp>
                10pt
              </samp>
               else.
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                <indexterm index="fn" number="610" mergedindex="cp">
                  \marginparwidth
                </indexterm>
                \marginparwidth
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <anchor name="marginal-notes-marginparwidth">
              marginal notes marginparwidth
            </anchor>
            <para>
              Width of the note itself; default for a one-sided
              <samp>
                10pt
              </samp>
               document is
              <samp>
                90pt
              </samp>
              ,
              <samp>
                83pt
              </samp>
               for
              <samp>
                11pt
              </samp>
              , and
              <samp>
                68pt
              </samp>
               for
              <samp>
                12pt
              </samp>
              ;
              <samp>
                17pt
              </samp>
               more in each case for a two-sided document. In two column mode, the default is
              <samp>
                48pt
              </samp>
              .
            </para>
          </tableitem>
        </tableentry>
      </ftable>
      <para>
        The standard
Default handler: &latex;
         routine for marginal notes does not prevent notes from falling off the bottom of the page.
Default handler: <!-- c @TeX{} FAQ entry on this topic (xx when there): -->
Default handler: <!-- c @url{http://www.tex.ac.uk/cgi-bin/texfaq2html?label=marginparside}. -->
Default handler: <!-- c (+marginfix) -->
      </para>
    </section>
  </chapter>
  <node name="Math-formulas" spaces=" ">
    <nodename>
      Math formulas
    </nodename>
    <nodenext automatic="on">
      Modes
    </nodenext>
    <nodeprev automatic="on">
      Making paragraphs
    </nodeprev>
    <nodeup automatic="on">
      Top
    </nodeup>
  </node>
  <chapter spaces=" ">
    <sectiontitle>
      Math formulas
    </sectiontitle>
    <cindex index="cp" spaces=" ">
      <indexterm index="cp" number="639">
        math formulas
      </indexterm>
    </cindex>
    <cindex index="cp" spaces=" ">
      <indexterm index="cp" number="640">
        formulas, math
      </indexterm>
    </cindex>
    <cindex index="cp" spaces=" ">
      <indexterm index="cp" number="641">
        math mode, entering
      </indexterm>
    </cindex>
    <findex index="fn" spaces=" ">
      <indexterm index="fn" number="611" mergedindex="cp">
        <r>
          environment
        </r>
        ,
        <code>
          math
        </code>
      </indexterm>
    </findex>
    <findex index="fn" spaces=" ">
      <indexterm index="fn" number="612" mergedindex="cp">
        <code>
          math
        </code>
        <r>
          environment
        </r>
      </indexterm>
    </findex>
    <findex index="fn" spaces=" ">
      <indexterm index="fn" number="613" mergedindex="cp">
        <r>
          environment
        </r>
        ,
        <code>
          displaymath
        </code>
      </indexterm>
    </findex>
    <findex index="fn" spaces=" ">
      <indexterm index="fn" number="614" mergedindex="cp">
        <code>
          displaymath
        </code>
        <r>
          environment
        </r>
      </indexterm>
    </findex>
    <findex index="fn" spaces=" ">
      <indexterm index="fn" number="615" mergedindex="cp">
        <r>
          environment
        </r>
        ,
        <code>
          equation
        </code>
      </indexterm>
    </findex>
    <findex index="fn" spaces=" ">
      <indexterm index="fn" number="616" mergedindex="cp">
        <code>
          equation
        </code>
        <r>
          environment
        </r>
      </indexterm>
    </findex>
    <para>
      Produce mathematical text by putting
Default handler: &latex;
       into math mode or display math mode (
      <pxref label="Modes">
        <xrefnodename>
          Modes
        </xrefnodename>
      </pxref>
      ). This example shows both.
    </para>
    <example endspaces=" ">
      <pre xml:space="preserve">
        The wave equation for \( u \) is \begin
Default handler: &lbrace;
        displaymath
Default handler: &rbrace;
         \frac
Default handler: &lbrace;
        \partial^2u
Default handler: &rbrace;
Default handler: &lbrace;
        \partial t^2
Default handler: &rbrace;
         = c^2\nabla^2u \end
Default handler: &lbrace;
        displaymath
Default handler: &rbrace;
         where \( \nabla^2 \) is the spatial Laplacian and \( c \) is constant.
      </pre>
    </example>
    <noindent/>
    <para>
      Math mode is for inline mathematics. In the above example it is invoked by the starting
      <code>
        \(
      </code>
       and finished by the matching ending
      <code>
        \)
      </code>
      . Display math mode is for displayed equations and here is invoked by the
      <code>
        displaymath
      </code>
       environment. Note that any mathematical text whatever, including mathematical text consisting of just one character, is handled in math mode.
    </para>
    <para>
      When in math mode or display math mode,
Default handler: &latex;
       handles many aspects of your input text differently than in other text modes. For example,
    </para>
    <example endspaces=" ">
      <pre xml:space="preserve">
        contrast x+y with \( x+y \)
      </pre>
    </example>
    <noindent/>
    <para>
      in math mode the letters are in italics and the spacing around the plus sign is different.
    </para>
    <para>
      There are three ways to make inline formulas, to put
Default handler: &latex;
       in math mode.
    </para>
    <example endspaces=" ">
      <pre xml:space="preserve">
        \(
        <var>
          mathematical material
        </var>
         \) $
        <var>
          mathematical material
        </var>
         $ \begin
Default handler: &lbrace;
        math
Default handler: &rbrace;
        <var>
          mathematical material
        </var>
         \end
Default handler: &lbrace;
        math
Default handler: &rbrace;
      </pre>
    </example>
    <noindent/>
    <para>
      The first form is preferred and the second is quite common, but the third form is rarely used. You can sometimes use one and sometimes another, as in
      <code>
        \(x\) and $y$
      </code>
      . You can use these in paragraph mode or in LR mode (
      <pxref label="Modes">
        <xrefnodename>
          Modes
        </xrefnodename>
      </pxref>
      ).
    </para>
    <para>
      To make displayed formulas, put
Default handler: &latex;
       into display math mode with either:
    </para>
    <example endspaces=" ">
      <pre xml:space="preserve">
        \begin
Default handler: &lbrace;
        displaymath
Default handler: &rbrace;
        <var>
          mathematical material
        </var>
         \end
Default handler: &lbrace;
        displaymath
Default handler: &rbrace;
      </pre>
    </example>
    <noindent/>
    <para>
      or
    </para>
    <example endspaces=" ">
      <pre xml:space="preserve">
        \begin
Default handler: &lbrace;
        equation
Default handler: &rbrace;
        <var>
          mathematical material
        </var>
         \end
Default handler: &lbrace;
        equation
Default handler: &rbrace;
      </pre>
    </example>
    <noindent/>
    <para>
      (
      <pxref label="displaymath">
        <xrefnodename>
          displaymath
        </xrefnodename>
      </pxref>
      ,
      <pxref label="equation">
        <xrefnodename>
          equation
        </xrefnodename>
      </pxref>
      ). The only difference is that with the
      <code>
        equation
      </code>
       environment,
Default handler: &latex;
       puts a formula number alongside the formula. The construct
      <code>
        \[
        <var>
          math
        </var>
         \]
      </code>
       is equivalent to
      <code>
        \begin
Default handler: &lbrace;
        displaymath
Default handler: &rbrace;
        <var>
          math
        </var>
         \end
Default handler: &lbrace;
        displaymath
Default handler: &rbrace;
      </code>
      . These environments can only be used in paragraph mode (
      <pxref label="Modes">
        <xrefnodename>
          Modes
        </xrefnodename>
      </pxref>
      ).
    </para>
    <cindex index="cp" spaces=" ">
      <indexterm index="cp" number="642">
        <r>
          package
        </r>
        ,
        <code>
          amsmath
        </code>
      </indexterm>
    </cindex>
    <cindex index="cp" spaces=" ">
      <indexterm index="cp" number="643">
        <code>
          amsmath
        </code>
        <r>
          package
        </r>
      </indexterm>
    </cindex>
    <cindex index="cp" spaces=" ">
      <indexterm index="cp" number="644">
        <r>
          package
        </r>
        ,
        <code>
          amsfonts
        </code>
      </indexterm>
    </cindex>
    <cindex index="cp" spaces=" ">
      <indexterm index="cp" number="645">
        <code>
          amsfonts
        </code>
        <r>
          package
        </r>
      </indexterm>
    </cindex>
    <cindex index="cp" spaces=" ">
      <indexterm index="cp" number="646">
        <r>
          package
        </r>
        ,
        <code>
          mathtools
        </code>
      </indexterm>
    </cindex>
    <cindex index="cp" spaces=" ">
      <indexterm index="cp" number="647">
        <code>
          mathtools
        </code>
        <r>
          package
        </r>
      </indexterm>
    </cindex>
    <para>
      The American Mathematical Society has made freely available a set of packages that greatly expand your options for writing mathematics,
      <code>
        amsmath
      </code>
       and
      <code>
        amssymb
      </code>
       (also be aware of the
      <code>
        mathtools
      </code>
       package that is an extension to, and loads,
      <code>
        amsmath
      </code>
      ). New documents that will have mathematical text should use these packages. Descriptions of these packages is outside the scope of this document; see their documentation on CTAN.
    </para>
    <menu endspaces=" ">
      <menuentry>
        <menuleadingtext>
          *
        </menuleadingtext>
        <menunode>
          Subscripts
          &
           superscripts
        </menunode>
        <menuseparator>
          ::
        </menuseparator>
        <menudescription>
          <pre xml:space="preserve">
            Also known as exponents or indices.
          </pre>
        </menudescription>
      </menuentry>
      <menuentry>
        <menuleadingtext>
          *
        </menuleadingtext>
        <menunode>
          Math symbols
        </menunode>
        <menuseparator>
          ::
        </menuseparator>
        <menudescription>
          <pre xml:space="preserve">
            Various mathematical squiggles.
          </pre>
        </menudescription>
      </menuentry>
      <menuentry>
        <menuleadingtext>
          *
        </menuleadingtext>
        <menunode>
          Math functions
        </menunode>
        <menuseparator>
          ::
        </menuseparator>
        <menudescription>
          <pre xml:space="preserve">
            Math function names like sin and exp.
          </pre>
        </menudescription>
      </menuentry>
      <menuentry>
        <menuleadingtext>
          *
        </menuleadingtext>
        <menunode>
          Math accents
        </menunode>
        <menuseparator>
          ::
        </menuseparator>
        <menudescription>
          <pre xml:space="preserve">
            Accents in math.
          </pre>
        </menudescription>
      </menuentry>
      <menuentry>
        <menuleadingtext>
          *
        </menuleadingtext>
        <menunode>
          Over- or under math
        </menunode>
        <menuseparator>
          ::
        </menuseparator>
        <menudescription>
          <pre xml:space="preserve">
            Lines, braces, arrows over/under formulas.
          </pre>
        </menudescription>
      </menuentry>
      <menuentry>
        <menuleadingtext>
          *
        </menuleadingtext>
        <menunode>
          Spacing in math mode
        </menunode>
        <menuseparator>
          ::
        </menuseparator>
        <menudescription>
          <pre xml:space="preserve">
            Thick, medium, thin, and negative spaces.
          </pre>
        </menudescription>
      </menuentry>
      <menuentry>
        <menuleadingtext>
          *
        </menuleadingtext>
        <menunode>
          Math styles
        </menunode>
        <menuseparator>
          ::
        </menuseparator>
        <menudescription>
          <pre xml:space="preserve">
            Determine the size of things.
          </pre>
        </menudescription>
      </menuentry>
      <menuentry>
        <menuleadingtext>
          *
        </menuleadingtext>
        <menunode>
          Math miscellany
        </menunode>
        <menuseparator>
          ::
        </menuseparator>
        <menudescription>
          <pre xml:space="preserve">
            Stuff that doesn
Default handler: &textrsquo;
            t fit anywhere else.
          </pre>
        </menudescription>
      </menuentry>
    </menu>
    <node name="Subscripts-_0026-superscripts" spaces=" ">
      <nodename>
        Subscripts
        &
         superscripts
      </nodename>
      <nodenext automatic="on">
        Math symbols
      </nodenext>
      <nodeup automatic="on">
        Math formulas
      </nodeup>
    </node>
    <section spaces=" ">
      <sectiontitle>
        Subscripts
        &
         superscripts
      </sectiontitle>
      <anchor name="superscript">
        superscript
      </anchor>
      <anchor name="subscript">
        subscript
      </anchor>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="648">
          superscript
        </indexterm>
      </cindex>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="649">
          subscript
        </indexterm>
      </cindex>
      <findex index="fn" spaces=" ">
        <indexterm index="fn" number="617" mergedindex="cp">
          ^
          <r>
            superscript
          </r>
        </indexterm>
      </findex>
      <findex index="fn" spaces=" ">
        <indexterm index="fn" number="618" mergedindex="cp">
          _
          <r>
            subscript
          </r>
        </indexterm>
      </findex>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="650">
          exponent
        </indexterm>
      </cindex>
      <para>
        Synopsis (in math mode or display math mode), one of:
      </para>
      <example endspaces=" ">
        <pre xml:space="preserve">
          <var>
            base
          </var>
          ^
          <var>
            exp
          </var>
          <var>
            base
          </var>
          ^
Default handler: &lbrace;
          <var>
            exp
          </var>
Default handler: &rbrace;
        </pre>
      </example>
      <noindent/>
      <para>
        or, one of:
      </para>
      <example endspaces=" ">
        <pre xml:space="preserve">
          <var>
            base
          </var>
          _
          <var>
            exp
          </var>
          <var>
            base
          </var>
          _
Default handler: &lbrace;
          <var>
            exp
          </var>
Default handler: &rbrace;
        </pre>
      </example>
      <para>
        Make
        <var>
          exp
        </var>
         appear as a superscript of
        <var>
          base
        </var>
         (with the caret character,
Default handler: &nbsp;
        <code>
          ^
        </code>
        ) or a subscript (with underscore,
Default handler: &nbsp;
        <code>
          _
        </code>
        ).
      </para>
      <para>
        In this example the
        <code>
          0
        </code>
Default handler: &textrsquo;
        s and
        <code>
          1
        </code>
Default handler: &textrsquo;
        s are subscripts while the
        <code>
          2
        </code>
Default handler: &textrsquo;
        s are superscripts.
      </para>
      <example endspaces=" ">
        <pre xml:space="preserve">
          \( (x_0+x_1)^2 \leq (x_0)^2+(x_1)^2 \)
        </pre>
      </example>
      <para>
        To have the subscript or superscript contain more than one character, surround the expression with curly braces, as in
        <code>
          e^
Default handler: &lbrace;
          -2x
Default handler: &rbrace;
        </code>
        . This example
Default handler: &textrsquo;
        s fourth line shows curly braces used to group an expression for the exponent.
      </para>
      <example endspaces=" ">
        <pre xml:space="preserve">
          \begin
Default handler: &lbrace;
          displaymath
Default handler: &rbrace;
           (3^3)^3=27^3=19\,683 \qquad 3^
Default handler: &lbrace;
          (3^3)
Default handler: &rbrace;
          =3^
Default handler: &lbrace;
          27
Default handler: &rbrace;
          =7\,625\,597\,484\,987 \end
Default handler: &lbrace;
          displaymath
Default handler: &rbrace;
        </pre>
      </example>
      <paraDefault handler: &latex;
>
         knows how to handle a superscript on a superscript, or a subscript on a subscript, or supers on subs, or subs on supers. So, expressions such as
        <code>
          e^
Default handler: &lbrace;
          x^2
Default handler: &rbrace;
        </code>
         and
        <code>
          x_
Default handler: &lbrace;
          i_0
Default handler: &rbrace;
        </code>
         give correct output. Note the use in those expressions of curly braces to give the
        <var>
          base
        </var>
         a determined
        <var>
          exp
        </var>
        . If you enter
        <code>
          \(3^3^3\)
        </code>
        , this interpreted as
        <code>
          \(3^
Default handler: &lbrace;
          3
Default handler: &rbrace;
          ^
Default handler: &lbrace;
          3
Default handler: &rbrace;
          \)
        </code>
         and then you get
Default handler: &tex;
         error
        <samp>
          Double superscript
        </samp>
        .
      </para>
      <paraDefault handler: &latex;
>
         does the right thing when something has both a subscript and a superscript. In this example the integral has both. They come out in the correct place without any author intervention.
      </para>
      <example endspaces=" ">
        <pre xml:space="preserve">
          \begin
Default handler: &lbrace;
          displaymath
Default handler: &rbrace;
           \int_
Default handler: &lbrace;
          x=a
Default handler: &rbrace;
          ^b f'(x)\,dx = f(b)-f(a) \end
Default handler: &lbrace;
          displaymath
Default handler: &rbrace;
        </pre>
      </example>
      <noindent/>
      <para>
        Note the curly braces around
        <code>
          x=a
        </code>
         to make the entire expression a subscript.
      </para>
      <para>
        To put a superscript or subscript before a symbol, use a construct like
        <codeDefault handler: &lbrace;
Default handler: &rbrace;
>
          _t K^2
        </code>
        . The empty curly braces
        <codeDefault handler: &lbrace;
Default handler: &rbrace;
/>
         give the subscript something to attach to and keeps it from accidentally attaching to a prior symbols.
      </para>
      <para>
        Using the subscript or superscript character outside of math mode or display math mode, as in
        <code>
          the expression x^2
        </code>
        , will get you the
Default handler: &tex;
         error
        <samp>
          Missing $ inserted
        </samp>
        .
      </para>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="651">
          <r>
            package
          </r>
          ,
          <code>
            mhchem
          </code>
        </indexterm>
      </cindex>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="652">
          <code>
            mhchem
          </code>
          <r>
            package
          </r>
        </indexterm>
      </cindex>
      <para>
        A common reason to want subscripts outside of a mathematics mode is to typeset chemical formulas. There are packages for that, such as
        <code>
          mhchem
        </code>
        ; see CTAN.
      </para>
    </section>
    <node name="Math-symbols" spaces=" ">
      <nodename>
        Math symbols
      </nodename>
      <nodenext automatic="on">
        Math functions
      </nodenext>
      <nodeprev automatic="on">
        Subscripts
        &
         superscripts
      </nodeprev>
      <nodeup automatic="on">
        Math formulas
      </nodeup>
    </node>
    <section spaces=" ">
      <sectiontitle>
        Math symbols
      </sectiontitle>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="653">
          math symbols
        </indexterm>
      </cindex>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="654">
          symbols, math
        </indexterm>
      </cindex>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="655">
          greek letters
        </indexterm>
      </cindex>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="656">
          <r>
            package
          </r>
          ,
          <code>
            comprehensive
          </code>
        </indexterm>
      </cindex>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="657">
          <code>
            comprehensive
          </code>
          <r>
            package
          </r>
        </indexterm>
      </cindex>
      <paraDefault handler: &latex;
>
         provides almost any mathematical or technical symbol that anyone uses. For example, if you include
        <code>
          $\pi$
        </code>
         in your source, you will get the pi symbol
        <u>
          03C0
        </u>
        . See the
Default handler: &textldquo;
        Comprehensive
Default handler: &latex;
         Symbol List
Default handler: &textrdquo;
         package at
        <url>
          <urefurl>
            https://ctan.org/pkg/comprehensive
          </urefurl>
        </url>
        .
      </para>
      <para>
        Here is a list of commonly-used symbols. It is by no means exhaustive. Each symbol is described with a short phrase, and its symbol class, which determines the spacing around it, is given in parenthesis. Unless said otherwise, the commands for these symbols can be used only in math mode. To redefine a command so that it can be used whatever the current mode, see
        <ref label="_005censuremath">
          <xrefnodename>
            \ensuremath
          </xrefnodename>
        </ref>
        .
      </para>
Default handler: <!-- c xx Add Negation: for negations of relevant symbols -->
Default handler: <!-- c Useful: http://www.w3.org/TR/WD-math-970515/section6.html -->
      <ftable commandarg="code" spaces=" " endspaces=" ">
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                <indexterm index="fn" number="619" mergedindex="cp">
                  \|
                </indexterm>
                \|
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <para>
              <u>
                2225
              </u>
               Parallel (relation). Synonym:
Default handler: &nbsp;
              <code>
                \parallel
              </code>
              .
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                <indexterm index="fn" number="620" mergedindex="cp">
                  \aleph
                </indexterm>
                \aleph
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <para>
              <u>
                2135
              </u>
               Aleph, transfinite cardinal (ordinary).
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                <indexterm index="fn" number="621" mergedindex="cp">
                  \alpha
                </indexterm>
                \alpha
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <para>
              <u>
                03B1
              </u>
               Lowercase Greek letter alpha (ordinary).
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                <indexterm index="fn" number="622" mergedindex="cp">
                  \amalg
                </indexterm>
                \amalg
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <para>
              <u>
                2A3F
              </u>
               Disjoint union (binary)
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                <indexterm index="fn" number="623" mergedindex="cp">
                  \angle
                </indexterm>
                \angle
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <para>
              <u>
                2220
              </u>
               Geometric angle (ordinary). Similar: less-than sign
Default handler: &nbsp;
              <code>
                <
              </code>
               and angle bracket
Default handler: &nbsp;
              <code>
                \langle
              </code>
              .
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                <indexterm index="fn" number="624" mergedindex="cp">
                  \approx
                </indexterm>
                \approx
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <para>
              <u>
                2248
              </u>
               Almost equal to (relation).
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                <indexterm index="fn" number="625" mergedindex="cp">
                  \ast
                </indexterm>
                \ast
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <para>
              <u>
                2217
              </u>
               Asterisk operator, convolution, six-pointed (binary). Synonym:
Default handler: &nbsp;
              <code>
                *
              </code>
              , which is often a superscript or subscript, as in the Kleene star. Similar:
Default handler: &nbsp;
              <code>
                \star
              </code>
              , which is five-pointed, and is sometimes used as a general binary operation, and sometimes reserved for cross-correlation.
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                <indexterm index="fn" number="626" mergedindex="cp">
                  \asymp
                </indexterm>
                \asymp
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <para>
              <u>
                224D
              </u>
               Asymptotically equivalent (relation).
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                <indexterm index="fn" number="627" mergedindex="cp">
                  \backslash
                </indexterm>
                \backslash
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <para>
              \ Backslash (ordinary). Similar: set minus
Default handler: &nbsp;
              <code>
                \setminus
              </code>
              , and
              <code>
                \textbackslash
              </code>
               for backslash outside of math mode.
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                <indexterm index="fn" number="628" mergedindex="cp">
                  \beta
                </indexterm>
                \beta
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <para>
              <u>
                03B2
              </u>
               Lowercase Greek letter beta (ordinary).
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                <indexterm index="fn" number="629" mergedindex="cp">
                  \bigcap
                </indexterm>
                \bigcap
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <para>
              <u>
                22C2
              </u>
               Variable-sized, or n-ary, intersection (operator). Similar: binary intersection
Default handler: &nbsp;
              <code>
                \cap
              </code>
              .
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                <indexterm index="fn" number="630" mergedindex="cp">
                  \bigcirc
                </indexterm>
                \bigcirc
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <para>
              <u>
                26AA
              </u>
               Circle, larger (binary). Similar: function composition
Default handler: &nbsp;
              <code>
                \circ
              </code>
              .
Default handler: <!-- c bb Best unicode symbol for this? -->
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                <indexterm index="fn" number="631" mergedindex="cp">
                  \bigcup
                </indexterm>
                \bigcup
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <para>
              <u>
                22C3
              </u>
               Variable-sized, or n-ary, union (operator). Similar: binary union
Default handler: &nbsp;
              <code>
                \cup
              </code>
              .
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                <indexterm index="fn" number="632" mergedindex="cp">
                  \bigodot
                </indexterm>
                \bigodot
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <para>
              <u>
                2A00
              </u>
               Variable-sized, or n-ary, circled dot operator (operator).
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                <indexterm index="fn" number="633" mergedindex="cp">
                  \bigoplus
                </indexterm>
                \bigoplus
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <para>
              <u>
                2A01
              </u>
               Variable-sized, or n-ary, circled plus operator (operator).
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                <indexterm index="fn" number="634" mergedindex="cp">
                  \bigotimes
                </indexterm>
                \bigotimes
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <para>
              <u>
                2A02
              </u>
               Variable-sized, or n-ary, circled times operator (operator).
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                <indexterm index="fn" number="635" mergedindex="cp">
                  \bigtriangledown
                </indexterm>
                \bigtriangledown
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <para>
              <u>
                25BD
              </u>
               Variable-sized, or n-ary, open triangle pointing down (binary). Synonym:
              <var>
                \varbigtriangledown
              </var>
              .
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                <indexterm index="fn" number="636" mergedindex="cp">
                  \bigtriangleup
                </indexterm>
                \bigtriangleup
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <para>
              <u>
                25B3
              </u>
               Variable-sized, or n-ary, open triangle pointing up (binary). Synonym:
              <var>
                \varbigtriangleup
              </var>
              .
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                <indexterm index="fn" number="637" mergedindex="cp">
                  \bigsqcup
                </indexterm>
                \bigsqcup
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <para>
              <u>
                2A06
              </u>
               Variable-sized, or n-ary, square union (operator).
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                <indexterm index="fn" number="638" mergedindex="cp">
                  \biguplus
                </indexterm>
                \biguplus
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <para>
              <u>
                2A04
              </u>
               Variable-sized, or n-ary, union operator with a plus (operator). (Note that the name has only one p.)
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                <indexterm index="fn" number="639" mergedindex="cp">
                  \bigvee
                </indexterm>
                \bigvee
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <para>
              <u>
                22C1
              </u>
               Variable-sized, or n-ary, logical-or (operator).
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                <indexterm index="fn" number="640" mergedindex="cp">
                  \bigwedge
                </indexterm>
                \bigwedge
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <para>
              <u>
                22C0
              </u>
               Variable-sized, or n-ary, logical-and (operator).
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                <indexterm index="fn" number="641" mergedindex="cp">
                  \bot
                </indexterm>
                \bot
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <para>
              <u>
                22A5
              </u>
              , Up tack, bottom, least element of a partially ordered set, or a contradiction (ordinary). See also
Default handler: &nbsp;
              <code>
                \top
              </code>
              .
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                <indexterm index="fn" number="642" mergedindex="cp">
                  \bowtie
                </indexterm>
                \bowtie
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <para>
              <u>
                22C8
              </u>
               Natural join of two relations (relation).
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                <indexterm index="fn" number="643" mergedindex="cp">
                  \Box
                </indexterm>
                \Box
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <para>
              <u>
                25A1
              </u>
               Modal operator for necessity; square open box (ordinary). Not available in plain
Default handler: &tex;
              . In
Default handler: &latex;
               you need to load the
              <code>
                amssymb
              </code>
               package.
Default handler: <!-- c bb Best Unicode equivalent? -->
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                <indexterm index="fn" number="644" mergedindex="cp">
                  \bullet
                </indexterm>
                \bullet
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <cindex index="cp" spaces=" ">
              <indexterm index="cp" number="658">
                bullet symbol
              </indexterm>
            </cindex>
            <para>
              <u>
                2022
              </u>
               Bullet (binary). Similar: multiplication dot
Default handler: &nbsp;
              <code>
                \cdot
              </code>
              .
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                <indexterm index="fn" number="645" mergedindex="cp">
                  \cap
                </indexterm>
                \cap
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <para>
              <u>
                2229
              </u>
               Intersection of two sets (binary). Similar: variable-sized operator
Default handler: &nbsp;
              <code>
                \bigcap
              </code>
              .
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                <indexterm index="fn" number="646" mergedindex="cp">
                  \cdot
                </indexterm>
                \cdot
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <para>
              <u>
                22C5
              </u>
               Multiplication (binary). Similar: Bullet dot
Default handler: &nbsp;
              <code>
                \bullet
              </code>
              .
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                <indexterm index="fn" number="647" mergedindex="cp">
                  \chi
                </indexterm>
                \chi
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <para>
              <u>
                03C7
              </u>
               Lowercase Greek chi (ordinary).
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                <indexterm index="fn" number="648" mergedindex="cp">
                  \circ
                </indexterm>
                \circ
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <para>
              <u>
                2218
              </u>
               Function composition, ring operator (binary). Similar: variable-sized operator
Default handler: &nbsp;
              <code>
                \bigcirc
              </code>
              .
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                <indexterm index="fn" number="649" mergedindex="cp">
                  \clubsuit
                </indexterm>
                \clubsuit
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <para>
              <u>
                2663
              </u>
               Club card suit (ordinary).
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                <indexterm index="fn" number="650" mergedindex="cp">
                  \complement
                </indexterm>
                \complement
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <para>
              <u>
                2201
              </u>
              , Set complement, used as a superscript as in
              <code>
                $S^\complement$
              </code>
               (ordinary). Not available in plain
Default handler: &tex;
              . In
Default handler: &latex;
               you need to load the
              <code>
                amssymb
              </code>
               package. Also used:
              <code>
                $S^
Default handler: &lbrace;
                \mathsf
Default handler: &lbrace;
                c
Default handler: &rbrace;
Default handler: &rbrace;
                $
              </code>
               or
Default handler: &nbsp;
              <code>
                $\bar
Default handler: &lbrace;
                S
Default handler: &rbrace;
                $
              </code>
              .
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                <indexterm index="fn" number="651" mergedindex="cp">
                  \cong
                </indexterm>
                \cong
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <para>
              <u>
                2245
              </u>
               Congruent (relation).
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                <indexterm index="fn" number="652" mergedindex="cp">
                  \coprod
                </indexterm>
                \coprod
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <para>
              <u>
                2210
              </u>
               Coproduct (operator).
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                <indexterm index="fn" number="653" mergedindex="cp">
                  \cup
                </indexterm>
                \cup
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <para>
              <u>
                222A
              </u>
               Union of two sets (binary). Similar: variable-sized operator
Default handler: &nbsp;
              <code>
                \bigcup
              </code>
              .
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                <indexterm index="fn" number="654" mergedindex="cp">
                  \dagger
                </indexterm>
                \dagger
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <para>
              <u>
                2020
              </u>
               Dagger relation (binary).
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                <indexterm index="fn" number="655" mergedindex="cp">
                  \dashv
                </indexterm>
                \dashv
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <para>
              <u>
                22A3
              </u>
               Dash with vertical, reversed turnstile (relation). Similar: turnstile
Default handler: &nbsp;
              <code>
                \vdash
              </code>
              .
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                <indexterm index="fn" number="656" mergedindex="cp">
                  \ddagger
                </indexterm>
                \ddagger
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <para>
              <u>
                2021
              </u>
               Double dagger relation (binary).
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                <indexterm index="fn" number="657" mergedindex="cp">
                  \Delta
                </indexterm>
                \Delta
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <para>
              <u>
                0394
              </u>
               Greek uppercase delta, used for increment (ordinary).
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                <indexterm index="fn" number="658" mergedindex="cp">
                  \delta
                </indexterm>
                \delta
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <para>
              <u>
                03B4
              </u>
               Greek lowercase delta (ordinary).
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                <indexterm index="fn" number="659" mergedindex="cp">
                  \Diamond
                </indexterm>
                \Diamond
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <para>
              <u>
                25C7
              </u>
               Large diamond operator (ordinary). Not available in plain
Default handler: &tex;
              . In
Default handler: &latex;
               you need to load the
              <code>
                amssymb
              </code>
               package.
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                <indexterm index="fn" number="660" mergedindex="cp">
                  \diamond
                </indexterm>
                \diamond
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <para>
              <u>
                22C4
              </u>
               Diamond operator (binary). Similar: large diamond
Default handler: &nbsp;
              <code>
                \Diamond
              </code>
              , circle bullet
Default handler: &nbsp;
              <code>
                \bullet
              </code>
              .
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                <indexterm index="fn" number="661" mergedindex="cp">
                  \diamondsuit
                </indexterm>
                \diamondsuit
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <para>
              <u>
                2662
              </u>
               Diamond card suit (ordinary).
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                <indexterm index="fn" number="662" mergedindex="cp">
                  \div
                </indexterm>
                \div
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <para>
              <u>
                00F7
              </u>
               Division sign (binary).
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                <indexterm index="fn" number="663" mergedindex="cp">
                  \doteq
                </indexterm>
                \doteq
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <para>
              <u>
                2250
              </u>
               Approaches the limit (relation). Similar: geometrically equal to
Default handler: &nbsp;
              <code>
                \Doteq
              </code>
              .
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                <indexterm index="fn" number="664" mergedindex="cp">
                  \downarrow
                </indexterm>
                \downarrow
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <para>
              <u>
                2193
              </u>
               Down arrow, converges (relation). Similar:
              <code>
                \Downarrow
              </code>
               double line down arrow.
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                <indexterm index="fn" number="665" mergedindex="cp">
                  \Downarrow
                </indexterm>
                \Downarrow
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <para>
              <u>
                21D3
              </u>
               Double line down arrow (relation). Similar:
              <code>
                \downarrow
              </code>
               single line down arrow.
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                <indexterm index="fn" number="666" mergedindex="cp">
                  \ell
                </indexterm>
                \ell
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <para>
              <u>
                2113
              </u>
               Lowercase cursive letter l (ordinary).
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                <indexterm index="fn" number="667" mergedindex="cp">
                  \emptyset
                </indexterm>
                \emptyset
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <para>
              <u>
                2205
              </u>
               Empty set symbol (ordinary). The variant form is
              <code>
                \varnothing
              </code>
              .
Default handler: <!-- c bb Why Unicode has \revemptyset but no \emptyset? -->
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                <indexterm index="fn" number="668" mergedindex="cp">
                  \epsilon
                </indexterm>
                \epsilon
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <para>
              <u>
                03F5
              </u>
               Lowercase lunate epsilon (ordinary). Similar to Greek text letter. More widely used in mathematics is the script small letter epsilon
              <code>
                \varepsilon
              </code>
Default handler: &nbsp;
              <u>
                03B5
              </u>
              . Related: the set membership relation
              <code>
                \in
              </code>
Default handler: &nbsp;
              <u>
                2208
              </u>
              .
Default handler: <!-- c src: David Carlisle http://tex.stackexchange.com/a/98018/339 and -->
Default handler: <!-- c Unicode referenced there asserts varepsilon is much more widely used. -->
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                <indexterm index="fn" number="669" mergedindex="cp">
                  \equiv
                </indexterm>
                \equiv
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <para>
              <u>
                2261
              </u>
               Equivalence (relation).
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                <indexterm index="fn" number="670" mergedindex="cp">
                  \eta
                </indexterm>
                \eta
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <para>
              <u>
                03B7
              </u>
               Lowercase Greek letter (ordinary).
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                <indexterm index="fn" number="671" mergedindex="cp">
                  \exists
                </indexterm>
                \exists
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <para>
              <u>
                2203
              </u>
               Existential quantifier (ordinary).
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                <indexterm index="fn" number="672" mergedindex="cp">
                  \flat
                </indexterm>
                \flat
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <para>
              <u>
                266D
              </u>
               Musical flat (ordinary).
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                <indexterm index="fn" number="673" mergedindex="cp">
                  \forall
                </indexterm>
                \forall
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <para>
              <u>
                2200
              </u>
               Universal quantifier (ordinary).
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                <indexterm index="fn" number="674" mergedindex="cp">
                  \frown
                </indexterm>
                \frown
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <para>
              <u>
                2322
              </u>
               Downward curving arc (ordinary).
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                <indexterm index="fn" number="675" mergedindex="cp">
                  \Gamma
                </indexterm>
                \Gamma
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <para>
              <u>
                0393
              </u>
               uppercase Greek letter (ordinary).
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                <indexterm index="fn" number="676" mergedindex="cp">
                  \gamma
                </indexterm>
                \gamma
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <para>
              <u>
                03B3
              </u>
               Lowercase Greek letter (ordinary).
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                <indexterm index="fn" number="677" mergedindex="cp">
                  \ge
                </indexterm>
                \ge
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <para>
              <u>
                2265
              </u>
               Greater than or equal to (relation). This is a synonym for
Default handler: &nbsp;
              <code>
                \geq
              </code>
              .
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                <indexterm index="fn" number="678" mergedindex="cp">
                  \geq
                </indexterm>
                \geq
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <para>
              <u>
                2265
              </u>
               Greater than or equal to (relation). This is a synonym for
Default handler: &nbsp;
              <code>
                \ge
              </code>
              .
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                <indexterm index="fn" number="679" mergedindex="cp">
                  \gets
                </indexterm>
                \gets
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <para>
              <u>
                2190
              </u>
               Is assigned the value (relation). Synonym:
Default handler: &nbsp;
              <code>
                \leftarrow
              </code>
              .
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                <indexterm index="fn" number="680" mergedindex="cp">
                  \gg
                </indexterm>
                \gg
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <para>
              <u>
                226B
              </u>
               Much greater than (relation). Similar: much less than
Default handler: &nbsp;
              <code>
                \ll
              </code>
              .
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                <indexterm index="fn" number="681" mergedindex="cp">
                  \hbar
                </indexterm>
                \hbar
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <para>
              <u>
                210F
              </u>
               Planck constant over two pi (ordinary).
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                <indexterm index="fn" number="682" mergedindex="cp">
                  \heartsuit
                </indexterm>
                \heartsuit
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <para>
              <u>
                2661
              </u>
               Heart card suit (ordinary).
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                <indexterm index="fn" number="683" mergedindex="cp">
                  \hookleftarrow
                </indexterm>
                \hookleftarrow
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <para>
              <u>
                21A9
              </u>
               Hooked left arrow (relation).
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                <indexterm index="fn" number="684" mergedindex="cp">
                  \hookrightarrow
                </indexterm>
                \hookrightarrow
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <para>
              <u>
                21AA
              </u>
               Hooked right arrow (relation).
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                <indexterm index="fn" number="685" mergedindex="cp">
                  \iff
                </indexterm>
                \iff
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <para>
              <u>
                27F7
              </u>
               If and only if (relation). It is
              <code>
                \Longleftrightarrow
              </code>
               with a
              <code>
                \thickmuskip
              </code>
               on either side.
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                <indexterm index="fn" number="686" mergedindex="cp">
                  \Im
                </indexterm>
                \Im
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <para>
              <u>
                2111
              </u>
               Imaginary part (ordinary). See: real part
Default handler: &nbsp;
              <code>
                \Re
              </code>
              .
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                <indexterm index="fn" number="687" mergedindex="cp">
                  \imath
                </indexterm>
                \imath
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <cindex index="cp" spaces=" ">
              <indexterm index="cp" number="659">
                dotless i, math
              </indexterm>
            </cindex>
            <para>
              Dotless i; used when you are putting an accent on an i (
              <pxref label="Math-accents">
                <xrefnodename>
                  Math accents
                </xrefnodename>
              </pxref>
              ).
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                <indexterm index="fn" number="688" mergedindex="cp">
                  \in
                </indexterm>
                \in
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <para>
              <u>
                2208
              </u>
               Set element (relation). See also: lowercase lunate epsilon
Default handler: &nbsp;
              <code>
                \epsilon
              </code>
              <u>
                03F5
              </u>
               and small letter script epsilon
Default handler: &nbsp;
              <code>
                \varepsilon
              </code>
              .
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                <indexterm index="fn" number="689" mergedindex="cp">
                  \infty
                </indexterm>
                \infty
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <para>
              <u>
                221E
              </u>
               Infinity (ordinary).
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                <indexterm index="fn" number="690" mergedindex="cp">
                  \int
                </indexterm>
                \int
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <para>
              <u>
                222B
              </u>
               Integral (operator).
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                <indexterm index="fn" number="691" mergedindex="cp">
                  \iota
                </indexterm>
                \iota
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <para>
              <u>
                03B9
              </u>
               Lowercase Greek letter (ordinary).
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                <indexterm index="fn" number="692" mergedindex="cp">
                  \Join
                </indexterm>
                \Join
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <para>
              <u>
                2A1D
              </u>
               Condensed bowtie symbol (relation). Not available in Plain
Default handler: &tex;
              .
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                <indexterm index="fn" number="693" mergedindex="cp">
                  \jmath
                </indexterm>
                \jmath
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <cindex index="cp" spaces=" ">
              <indexterm index="cp" number="660">
                dotless j, math
              </indexterm>
            </cindex>
            <para>
              Dotless j; used when you are putting an accent on a j (
              <pxref label="Math-accents">
                <xrefnodename>
                  Math accents
                </xrefnodename>
              </pxref>
              ).
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                <indexterm index="fn" number="694" mergedindex="cp">
                  \kappa
                </indexterm>
                \kappa
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <para>
              <u>
                03BA
              </u>
               Lowercase Greek letter (ordinary).
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                <indexterm index="fn" number="695" mergedindex="cp">
                  \Lambda
                </indexterm>
                \Lambda
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <para>
              <u>
                039B
              </u>
               uppercase Greek letter (ordinary).
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                <indexterm index="fn" number="696" mergedindex="cp">
                  \lambda
                </indexterm>
                \lambda
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <para>
              <u>
                03BB
              </u>
               Lowercase Greek letter (ordinary).
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                <indexterm index="fn" number="697" mergedindex="cp">
                  \land
                </indexterm>
                \land
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <para>
              <u>
                2227
              </u>
               Logical and (binary). Synonym:
Default handler: &nbsp;
              <code>
                \wedge
              </code>
              . See also logical
Default handler: &nbsp;
              or
Default handler: &nbsp;
              <code>
                \lor
              </code>
              .
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                <indexterm index="fn" number="698" mergedindex="cp">
                  \langle
                </indexterm>
                \langle
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <para>
              <u>
                27E8
              </u>
               Left angle, or sequence, bracket (opening). Similar: less-than
Default handler: &nbsp;
              <code>
                <
              </code>
              . Matches
Default handler: &nbsp;
              <code>
                \rangle
              </code>
              .
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                <indexterm index="fn" number="699" mergedindex="cp">
                  \lbrace
                </indexterm>
                \lbrace
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <para>
              <u>
                007B
              </u>
               Left curly brace (opening). Synonym:
Default handler: &nbsp;
              <code>
                \
Default handler: &lbrace;
              </code>
              . Matches
Default handler: &nbsp;
              <code>
                \rbrace
              </code>
              .
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                <indexterm index="fn" number="700" mergedindex="cp">
                  \lbrack
                </indexterm>
                \lbrack
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <para>
              <u>
                005B
              </u>
               Left square bracket (opening). Synonym:
Default handler: &nbsp;
              <code>
                [
              </code>
              . Matches
Default handler: &nbsp;
              <code>
                \rbrack
              </code>
              .
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                <indexterm index="fn" number="701" mergedindex="cp">
                  \lceil
                </indexterm>
                \lceil
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <para>
              <u>
                2308
              </u>
               Left ceiling bracket, like a square bracket but with the bottom shaved off (opening). Matches
Default handler: &nbsp;
              <code>
                \rceil
              </code>
              .
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                <indexterm index="fn" number="702" mergedindex="cp">
                  \le
                </indexterm>
                \le
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <para>
              <u>
                2264
              </u>
               Less than or equal to (relation). This is a synonym for
Default handler: &nbsp;
              <code>
                \leq
              </code>
              .
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                <indexterm index="fn" number="703" mergedindex="cp">
                  \leadsto
                </indexterm>
                \leadsto
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <para>
              <u>
                21DD
              </u>
               Squiggly right arrow (relation). To get this symbol outside of math mode you can put
              <code>
                \newcommand*
Default handler: &lbrace;
                \Leadsto
Default handler: &rbrace;
Default handler: &lbrace;
                \ensuremath
Default handler: &lbrace;
                \leadsto
Default handler: &rbrace;
Default handler: &rbrace;
              </code>
               in the preamble and then use
              <code>
                \Leadsto
              </code>
               instead.
Default handler: <!-- c bb Best Unicode equivalent? -->
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                <indexterm index="fn" number="704" mergedindex="cp">
                  \Leftarrow
                </indexterm>
                \Leftarrow
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <para>
              <u>
                21D0
              </u>
               Is implied by, double-line left arrow (relation). Similar: single-line left arrow
Default handler: &nbsp;
              <code>
                \leftarrow
              </code>
              .
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                <indexterm index="fn" number="705" mergedindex="cp">
                  \leftarrow
                </indexterm>
                \leftarrow
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <para>
              <u>
                2190
              </u>
               Single-line left arrow (relation). Synonym:
Default handler: &nbsp;
              <code>
                \gets
              </code>
              . Similar: double-line left arrow
Default handler: &nbsp;
              <code>
                \Leftarrow
              </code>
              .
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                <indexterm index="fn" number="706" mergedindex="cp">
                  \leftharpoondown
                </indexterm>
                \leftharpoondown
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <para>
              <u>
                21BD
              </u>
               Single-line left harpoon, barb under bar (relation).
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                <indexterm index="fn" number="707" mergedindex="cp">
                  \leftharpoonup
                </indexterm>
                \leftharpoonup
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <para>
              <u>
                21BC
              </u>
               Single-line left harpoon, barb over bar (relation).
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                <indexterm index="fn" number="708" mergedindex="cp">
                  \Leftrightarrow
                </indexterm>
                \Leftrightarrow
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <para>
              <u>
                21D4
              </u>
               Bi-implication; double-line double-headed arrow (relation). Similar: single-line double headed arrow
Default handler: &nbsp;
              <code>
                \leftrightarrow
              </code>
              .
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                <indexterm index="fn" number="709" mergedindex="cp">
                  \leftrightarrow
                </indexterm>
                \leftrightarrow
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <para>
              <u>
                2194
              </u>
               Single-line double-headed arrow (relation). Similar: double-line double headed arrow
Default handler: &nbsp;
              <code>
                \Leftrightarrow
              </code>
              .
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                <indexterm index="fn" number="710" mergedindex="cp">
                  \leq
                </indexterm>
                \leq
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <para>
              <u>
                2264
              </u>
               Less than or equal to (relation). This is a synonym for
Default handler: &nbsp;
              <code>
                \le
              </code>
              .
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                <indexterm index="fn" number="711" mergedindex="cp">
                  \lfloor
                </indexterm>
                \lfloor
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <para>
              <u>
                230A
              </u>
               Left floor bracket (opening). Matches:
Default handler: &nbsp;
              <code>
                \floor
              </code>
              .
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                <indexterm index="fn" number="712" mergedindex="cp">
                  \lhd
                </indexterm>
                \lhd
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <para>
              <u>
                25C1
              </u>
               Arrowhead, that is, triangle, pointing left (binary). For the normal subgroup symbol you should load
              <code>
                amssymb
              </code>
               and use
Default handler: &nbsp;
              <code>
                \vartriangleleft
              </code>
               (which is a relation and so gives better spacing).
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                <indexterm index="fn" number="713" mergedindex="cp">
                  \ll
                </indexterm>
                \ll
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <para>
              <u>
                226A
              </u>
               Much less than (relation). Similar: much greater than
Default handler: &nbsp;
              <code>
                \gg
              </code>
              .
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                <indexterm index="fn" number="714" mergedindex="cp">
                  \lnot
                </indexterm>
                \lnot
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <para>
              <u>
                00AC
              </u>
               Logical negation (ordinary). Synonym:
Default handler: &nbsp;
              <code>
                \neg
              </code>
              .
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                <indexterm index="fn" number="715" mergedindex="cp">
                  \longleftarrow
                </indexterm>
                \longleftarrow
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <para>
              <u>
                27F5
              </u>
               Long single-line left arrow (relation). Similar: long double-line left arrow
Default handler: &nbsp;
              <code>
                \Longleftarrow
              </code>
              .
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                <indexterm index="fn" number="716" mergedindex="cp">
                  \longleftrightarrow
                </indexterm>
                \longleftrightarrow
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <para>
              <u>
                27F7
              </u>
               Long single-line double-headed arrow (relation). Similar: long double-line double-headed arrow
Default handler: &nbsp;
              <code>
                \Longleftrightarrow
              </code>
              .
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                <indexterm index="fn" number="717" mergedindex="cp">
                  \longmapsto
                </indexterm>
                \longmapsto
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <para>
              <u>
                27FC
              </u>
               Long single-line left arrow starting with vertical bar (relation). Similar: shorter version
Default handler: &nbsp;
              <code>
                \mapsto
              </code>
              .
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                <indexterm index="fn" number="718" mergedindex="cp">
                  \longrightarrow
                </indexterm>
                \longrightarrow
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <para>
              <u>
                27F6
              </u>
               Long single-line right arrow (relation). Similar: long double-line right arrow
Default handler: &nbsp;
              <code>
                \Longrightarrow
              </code>
              .
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                <indexterm index="fn" number="719" mergedindex="cp">
                  \lor
                </indexterm>
                \lor
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <para>
              <u>
                2228
              </u>
               Logical or (binary). Synonym:
Default handler: &nbsp;
              <code>
                \vee
              </code>
              . See also logical
Default handler: &nbsp;
              and
Default handler: &nbsp;
              <code>
                \land
              </code>
              .
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                <indexterm index="fn" number="720" mergedindex="cp">
                  \mapsto
                </indexterm>
                \mapsto
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <para>
              <u>
                21A6
              </u>
               Single-line left arrow starting with vertical bar (relation). Similar: longer version
Default handler: &nbsp;
              <code>
                \longmapsto
              </code>
              .
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                <indexterm index="fn" number="721" mergedindex="cp">
                  \mho
                </indexterm>
                \mho
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <para>
              <u>
                2127
              </u>
               Conductance, half-circle rotated capital omega (ordinary).
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                <indexterm index="fn" number="722" mergedindex="cp">
                  \mid
                </indexterm>
                \mid
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <para>
              <u>
                2223
              </u>
               Single-line vertical bar (relation). A typical use of
              <code>
                \mid
              </code>
               is for a set
              <code>
                \
Default handler: &lbrace;
                \, x \mid x\geq 5 \,\
Default handler: &rbrace;
              </code>
              .
            </para>
            <para>
              Similar:
              <code>
                \vert
              </code>
               and
Default handler: &nbsp;
              <code>
                |
              </code>
               produce the same single-line vertical bar symbol but without any spacing (they fall in class ordinary) and you should not use them as relations but instead only as ordinals, i.e., footnote symbols. For absolute value, see the entry for
Default handler: &nbsp;
              <code>
                \vert
              </code>
               and for norm see the entry for
Default handler: &nbsp;
              <code>
                \Vert
              </code>
              .
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                <indexterm index="fn" number="723" mergedindex="cp">
                  \models
                </indexterm>
                \models
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <para>
              <u>
                22A8
              </u>
               Entails, or satisfies; double turnstile, short double dash (relation). Similar: long double dash
Default handler: &nbsp;
              <code>
                \vDash
              </code>
              .
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                <indexterm index="fn" number="724" mergedindex="cp">
                  \mp
                </indexterm>
                \mp
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <para>
              <u>
                2213
              </u>
               Minus or plus (relation).
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                <indexterm index="fn" number="725" mergedindex="cp">
                  \mu
                </indexterm>
                \mu
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <para>
              <u>
                03BC
              </u>
               Lowercase Greek letter (ordinary).
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                <indexterm index="fn" number="726" mergedindex="cp">
                  \nabla
                </indexterm>
                \nabla
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <para>
              <u>
                2207
              </u>
               Hamilton
Default handler: &textrsquo;
              s del, or differential, operator (ordinary).
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                <indexterm index="fn" number="727" mergedindex="cp">
                  \natural
                </indexterm>
                \natural
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <para>
              <u>
                266E
              </u>
               Musical natural notation (ordinary).
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                <indexterm index="fn" number="728" mergedindex="cp">
                  \ne
                </indexterm>
                \ne
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <para>
              <u>
                2260
              </u>
               Not equal (relation). Synonym:
Default handler: &nbsp;
              <code>
                \neq
              </code>
              .
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                <indexterm index="fn" number="729" mergedindex="cp">
                  \nearrow
                </indexterm>
                \nearrow
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <para>
              <u>
                2197
              </u>
               North-east arrow (relation).
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                <indexterm index="fn" number="730" mergedindex="cp">
                  \neg
                </indexterm>
                \neg
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <para>
              <u>
                00AC
              </u>
               Logical negation (ordinary). Synonym:
Default handler: &nbsp;
              <code>
                \lnot
              </code>
              . Sometimes instead used for negation:
Default handler: &nbsp;
              <code>
                \sim
              </code>
              .
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                <indexterm index="fn" number="731" mergedindex="cp">
                  \neq
                </indexterm>
                \neq
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <para>
              <u>
                2260
              </u>
               Not equal (relation). Synonym:
Default handler: &nbsp;
              <code>
                \ne
              </code>
              .
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                <indexterm index="fn" number="732" mergedindex="cp">
                  \ni
                </indexterm>
                \ni
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <para>
              <u>
                220B
              </u>
               Reflected membership epsilon; has the member (relation). Synonym:
Default handler: &nbsp;
              <code>
                \owns
              </code>
              . Similar: is a member of
Default handler: &nbsp;
              <code>
                \in
              </code>
              .
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                <indexterm index="fn" number="733" mergedindex="cp">
                  \not
                </indexterm>
                \not
              </itemformat>
            </item>
          </tableterm>
          <tableitemDefault handler: <!-- c the "@ "s put in spaces so the not slash doesn't hit the next char. -->
>
            <para>
              <u>
                0020
              </u>
              <spacecmd type="spc"/>
              <spacecmd type="spc"/>
              <spacecmd type="spc"/>
              <spacecmd type="spc"/>
              Long solidus, or slash, used to overstrike a following operator (relation).
            </para>
            <para>
              Many negated operators are available that don
Default handler: &textrsquo;
              t require
              <code>
                \not
              </code>
              , particularly with the
              <code>
                amssymb
              </code>
               package. For example,
              <code>
                \notin
              </code>
               is typographically preferable to
              <code>
                \not\in
              </code>
              .
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                <indexterm index="fn" number="734" mergedindex="cp">
                  \notin
                </indexterm>
                \notin
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <para>
              <u>
                2209
              </u>
               Not an element of (relation). Similar: not subset of
Default handler: &nbsp;
              <code>
                \nsubseteq
              </code>
              .
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                <indexterm index="fn" number="735" mergedindex="cp">
                  \nu
                </indexterm>
                \nu
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <para>
              <u>
                03BD
              </u>
               Lowercase Greek letter (ordinary).
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                <indexterm index="fn" number="736" mergedindex="cp">
                  \nwarrow
                </indexterm>
                \nwarrow
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <para>
              <u>
                2196
              </u>
               North-west arrow (relation).
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                <indexterm index="fn" number="737" mergedindex="cp">
                  \odot
                </indexterm>
                \odot
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <para>
              <u>
                2299
              </u>
               Dot inside a circle (binary). Similar: variable-sized operator
Default handler: &nbsp;
              <code>
                \bigodot
              </code>
              .
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                <indexterm index="fn" number="738" mergedindex="cp">
                  \oint
                </indexterm>
                \oint
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <para>
              <u>
                222E
              </u>
               Contour integral, integral with circle in the middle (operator).
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                <indexterm index="fn" number="739" mergedindex="cp">
                  \Omega
                </indexterm>
                \Omega
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <para>
              <u>
                03A9
              </u>
               uppercase Greek letter (ordinary).
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                <indexterm index="fn" number="740" mergedindex="cp">
                  \omega
                </indexterm>
                \omega
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <para>
              <u>
                03C9
              </u>
               Lowercase Greek letter (ordinary).
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                <indexterm index="fn" number="741" mergedindex="cp">
                  \ominus
                </indexterm>
                \ominus
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <para>
              <u>
                2296
              </u>
               Minus sign, or dash, inside a circle (binary).
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                <indexterm index="fn" number="742" mergedindex="cp">
                  \oplus
                </indexterm>
                \oplus
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <para>
              <u>
                2295
              </u>
               Plus sign inside a circle (binary). Similar: variable-sized operator
Default handler: &nbsp;
              <code>
                \bigoplus
              </code>
              .
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                <indexterm index="fn" number="743" mergedindex="cp">
                  \oslash
                </indexterm>
                \oslash
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <para>
              <u>
                2298
              </u>
               Solidus, or slash, inside a circle (binary).
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                <indexterm index="fn" number="744" mergedindex="cp">
                  \otimes
                </indexterm>
                \otimes
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <para>
              <u>
                2297
              </u>
               Times sign, or cross, inside a circle (binary). Similar: variable-sized operator
Default handler: &nbsp;
              <code>
                \bigotimes
              </code>
              .
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                <indexterm index="fn" number="745" mergedindex="cp">
                  \owns
                </indexterm>
                \owns
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <para>
              <u>
                220B
              </u>
               Reflected membership epsilon; has the member (relation). Synonym:
Default handler: &nbsp;
              <code>
                \ni
              </code>
              . Similar: is a member of
Default handler: &nbsp;
              <code>
                \in
              </code>
              .
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                <indexterm index="fn" number="746" mergedindex="cp">
                  \parallel
                </indexterm>
                \parallel
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <para>
              <u>
                2225
              </u>
               Parallel (relation). Synonym:
Default handler: &nbsp;
              <code>
                \|
              </code>
              .
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                <indexterm index="fn" number="747" mergedindex="cp">
                  \partial
                </indexterm>
                \partial
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <para>
              <u>
                2202
              </u>
               Partial differential (ordinary).
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                <indexterm index="fn" number="748" mergedindex="cp">
                  \perp
                </indexterm>
                \perp
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <para>
              <u>
                27C2
              </u>
               Perpendicular (relation). Similar:
Default handler: &nbsp;
              <code>
                \bot
              </code>
               uses the same glyph but the spacing is different because it is in the class ordinary.
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                <indexterm index="fn" number="749" mergedindex="cp">
                  \Phi
                </indexterm>
                \Phi
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <para>
              <u>
                03A6
              </u>
               Uppercase Greek letter (ordinary).
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                <indexterm index="fn" number="750" mergedindex="cp">
                  \phi
                </indexterm>
                \phi
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <para>
              <u>
                03D5
              </u>
               Lowercase Greek letter (ordinary). The variant form is
              <code>
                \varphi
              </code>
Default handler: &nbsp;
              <u>
                03C6
              </u>
              .
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                <indexterm index="fn" number="751" mergedindex="cp">
                  \Pi
                </indexterm>
                \Pi
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <para>
              <u>
                03A0
              </u>
               uppercase Greek letter (ordinary).
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                <indexterm index="fn" number="752" mergedindex="cp">
                  \pi
                </indexterm>
                \pi
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <para>
              <u>
                03C0
              </u>
               Lowercase Greek letter (ordinary). The variant form is
              <code>
                \varpi
              </code>
Default handler: &nbsp;
              <u>
                03D6
              </u>
              .
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                <indexterm index="fn" number="753" mergedindex="cp">
                  \pm
                </indexterm>
                \pm
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <para>
              <u>
                00B1
              </u>
               Plus or minus (binary).
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                <indexterm index="fn" number="754" mergedindex="cp">
                  \prec
                </indexterm>
                \prec
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <para>
              <u>
                227A
              </u>
               Precedes (relation). Similar: less than
Default handler: &nbsp;
              <code>
                <
              </code>
              .
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                <indexterm index="fn" number="755" mergedindex="cp">
                  \preceq
                </indexterm>
                \preceq
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <para>
              <u>
                2AAF
              </u>
               Precedes or equals (relation). Similar: less than or equals
Default handler: &nbsp;
              <code>
                \leq
              </code>
              .
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                <indexterm index="fn" number="756" mergedindex="cp">
                  \prime
                </indexterm>
                \prime
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <para>
              <u>
                2032
              </u>
               Prime, or minute in a time expression (ordinary). Typically used as a superscript:
              <code>
                $f^\prime$
              </code>
              ;
              <code>
                $f^\prime$
              </code>
               and
              <code>
                $f'$
              </code>
               produce the same result. An advantage of the second is that
              <code>
                $f'''$
              </code>
               produces the desired symbol, that is, the same result as
              <code>
                $f^
Default handler: &lbrace;
                \prime\prime\prime
Default handler: &rbrace;
                $
              </code>
              , but uses rather less typing. You can only use
              <code>
                \prime
              </code>
               in math mode. Using the right single quote
Default handler: &nbsp;
              <code>
                '
              </code>
               in text mode produces a different character (apostrophe).
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                <indexterm index="fn" number="757" mergedindex="cp">
                  \prod
                </indexterm>
                \prod
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <para>
              <u>
                220F
              </u>
               Product (operator).
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                <indexterm index="fn" number="758" mergedindex="cp">
                  \propto
                </indexterm>
                \propto
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <para>
              <u>
                221D
              </u>
               Is proportional to (relation)
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                <indexterm index="fn" number="759" mergedindex="cp">
                  \Psi
                </indexterm>
                \Psi
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <para>
              <u>
                03A8
              </u>
               uppercase Greek letter (ordinary).
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                <indexterm index="fn" number="760" mergedindex="cp">
                  \psi
                </indexterm>
                \psi
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <para>
              <u>
                03C8
              </u>
               Lowercase Greek letter (ordinary).
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                <indexterm index="fn" number="761" mergedindex="cp">
                  \rangle
                </indexterm>
                \rangle
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <para>
              <u>
                27E9
              </u>
               Right angle, or sequence, bracket (closing). Similar: greater than
Default handler: &nbsp;
              <code>
                >
              </code>
              . Matches:
              <code>
                \langle
              </code>
              .
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                <indexterm index="fn" number="762" mergedindex="cp">
                  \rbrace
                </indexterm>
                \rbrace
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <para>
              <u>
                007D
              </u>
               Right curly brace (closing). Synonym:
Default handler: &nbsp;
              <code>
                \
Default handler: &rbrace;
              </code>
              . Matches
Default handler: &nbsp;
              <code>
                \lbrace
              </code>
              .
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                <indexterm index="fn" number="763" mergedindex="cp">
                  \rbrack
                </indexterm>
                \rbrack
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <para>
              <u>
                005D
              </u>
               Right square bracket (closing). Synonym:
Default handler: &nbsp;
              <code>
                ]
              </code>
              . Matches
Default handler: &nbsp;
              <code>
                \lbrack
              </code>
              .
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                <indexterm index="fn" number="764" mergedindex="cp">
                  \rceil
                </indexterm>
                \rceil
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <para>
              <u>
                2309
              </u>
               Right ceiling bracket (closing). Matches
Default handler: &nbsp;
              <code>
                \lceil
              </code>
              .
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                <indexterm index="fn" number="765" mergedindex="cp">
                  \Re
                </indexterm>
                \Re
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <para>
              <u>
                211C
              </u>
               Real part, real numbers, cursive capital R (ordinary). Related: double-line, or blackboard bold, R
Default handler: &nbsp;
              <code>
                \mathbb
Default handler: &lbrace;
                R
Default handler: &rbrace;
              </code>
              ; to access this, load the
              <code>
                amsfonts
              </code>
               package.
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                <indexterm index="fn" number="766" mergedindex="cp">
                  \restriction
                </indexterm>
                \restriction
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <para>
              <u>
                21BE
              </u>
              , Restriction of a function (relation). Synonym:
              <code>
                \upharpoonright
              </code>
              . Not available in plain
Default handler: &tex;
              . In
Default handler: &latex;
               you need to load the
              <code>
                amssymb
              </code>
               package.
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                <indexterm index="fn" number="767" mergedindex="cp">
                  \revemptyset
                </indexterm>
                \revemptyset
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <para>
              <u>
                29B0
              </u>
              , Reversed empty set symbol (ordinary). Related:
              <code>
                \varnothing
              </code>
              . Not available in plain
Default handler: &tex;
              . In
Default handler: &latex;
               you need to load the
              <file>
                stix
              </file>
               package.
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                <indexterm index="fn" number="768" mergedindex="cp">
                  \rfloor
                </indexterm>
                \rfloor
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <para>
              <u>
                230B
              </u>
               Right floor bracket, a right square bracket with the top cut off (closing). Matches
Default handler: &nbsp;
              <code>
                \lfloor
              </code>
              .
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                <indexterm index="fn" number="769" mergedindex="cp">
                  \rhd
                </indexterm>
                \rhd
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <para>
              <u>
                25C1
              </u>
               Arrowhead, that is, triangle, pointing right (binary). For the normal subgroup symbol you should instead load
              <code>
                amssymb
              </code>
               and use
Default handler: &nbsp;
              <code>
                \vartriangleright
              </code>
               (which is a relation and so gives better spacing).
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                <indexterm index="fn" number="770" mergedindex="cp">
                  \rho
                </indexterm>
                \rho
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <para>
              <u>
                03C1
              </u>
               Lowercase Greek letter (ordinary). The variant form is
              <code>
                \varrho
              </code>
Default handler: &nbsp;
              <u>
                03F1
              </u>
              .
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                <indexterm index="fn" number="771" mergedindex="cp">
                  \Rightarrow
                </indexterm>
                \Rightarrow
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <para>
              <u>
                21D2
              </u>
               Implies, right-pointing double line arrow (relation). Similar: right single-line arrow
Default handler: &nbsp;
              <code>
                \rightarrow
              </code>
              .
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                <indexterm index="fn" number="772" mergedindex="cp">
                  \rightarrow
                </indexterm>
                \rightarrow
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <para>
              <u>
                2192
              </u>
               Right-pointing single line arrow (relation). Synonym:
Default handler: &nbsp;
              <code>
                \to
              </code>
              . Similar: right double line arrow
Default handler: &nbsp;
              <code>
                \Rightarrow
              </code>
              .
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                <indexterm index="fn" number="773" mergedindex="cp">
                  \rightharpoondown
                </indexterm>
                \rightharpoondown
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <para>
              <u>
                21C1
              </u>
               Right-pointing harpoon with barb below the line (relation).
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                <indexterm index="fn" number="774" mergedindex="cp">
                  \rightharpoonup
                </indexterm>
                \rightharpoonup
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <para>
              <u>
                21C0
              </u>
               Right-pointing harpoon with barb above the line (relation).
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                <indexterm index="fn" number="775" mergedindex="cp">
                  \rightleftharpoons
                </indexterm>
                \rightleftharpoons
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <para>
              <u>
                21CC
              </u>
               Right harpoon up above left harpoon down (relation).
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                <indexterm index="fn" number="776" mergedindex="cp">
                  \searrow
                </indexterm>
                \searrow
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <para>
              <u>
                2198
              </u>
               Arrow pointing southeast (relation).
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                <indexterm index="fn" number="777" mergedindex="cp">
                  \setminus
                </indexterm>
                \setminus
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <para>
              <u>
                29F5
              </u>
               Set difference, reverse solidus or reverse slash, like \ (binary). Similar: backslash
Default handler: &nbsp;
              <code>
                \backslash
              </code>
               and also
              <code>
                \textbackslash
              </code>
               outside of math mode.
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                <indexterm index="fn" number="778" mergedindex="cp">
                  \sharp
                </indexterm>
                \sharp
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <para>
              <u>
                266F
              </u>
               Musical sharp (ordinary).
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                <indexterm index="fn" number="779" mergedindex="cp">
                  \Sigma
                </indexterm>
                \Sigma
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <para>
              <u>
                03A3
              </u>
               uppercase Greek letter (ordinary).
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                <indexterm index="fn" number="780" mergedindex="cp">
                  \sigma
                </indexterm>
                \sigma
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <para>
              <u>
                03C3
              </u>
               Lowercase Greek letter (ordinary). The variant form is
              <code>
                \varsigma
              </code>
Default handler: &nbsp;
              <u>
                03C2
              </u>
              .
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                <indexterm index="fn" number="781" mergedindex="cp">
                  \sim
                </indexterm>
                \sim
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <para>
              <u>
                223C
              </u>
               Similar, in a relation (relation).
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                <indexterm index="fn" number="782" mergedindex="cp">
                  \simeq
                </indexterm>
                \simeq
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <para>
              <u>
                2243
              </u>
               Similar or equal to, in a relation (relation).
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                <indexterm index="fn" number="783" mergedindex="cp">
                  \smallint
                </indexterm>
                \smallint
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <para>
              <u>
                222B
              </u>
               Integral sign that does not change to a larger size in a display (operator).
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                <indexterm index="fn" number="784" mergedindex="cp">
                  \smile
                </indexterm>
                \smile
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <para>
              <u>
                2323
              </u>
               Upward curving arc, smile (ordinary).
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                <indexterm index="fn" number="785" mergedindex="cp">
                  \spadesuit
                </indexterm>
                \spadesuit
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <para>
              <u>
                2660
              </u>
               Spade card suit (ordinary).
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                <indexterm index="fn" number="786" mergedindex="cp">
                  \sqcap
                </indexterm>
                \sqcap
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <para>
              <u>
                2293
              </u>
               Square intersection symbol (binary). Similar: intersection
Default handler: &nbsp;
              <code>
                cap
              </code>
              .
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                <indexterm index="fn" number="787" mergedindex="cp">
                  \sqcup
                </indexterm>
                \sqcup
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <para>
              <u>
                2294
              </u>
               Square union symbol (binary). Similar: union
Default handler: &nbsp;
              <code>
                cup
              </code>
              . Related: variable-sized operator
Default handler: &nbsp;
              <code>
                \bigsqcup
              </code>
              .
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                <indexterm index="fn" number="788" mergedindex="cp">
                  \sqsubset
                </indexterm>
                \sqsubset
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <para>
              <u>
                228F
              </u>
              , Square subset symbol (relation). Similar: subset
Default handler: &nbsp;
              <code>
                \subset
              </code>
              . Not available in plain
Default handler: &tex;
              . In
Default handler: &latex;
               you need to load the
              <code>
                amssymb
              </code>
               package.
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                <indexterm index="fn" number="789" mergedindex="cp">
                  \sqsubseteq
                </indexterm>
                \sqsubseteq
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <para>
              <u>
                2291
              </u>
               Square subset or equal symbol (binary). Similar: subset or equal to
Default handler: &nbsp;
              <code>
                \subseteq
              </code>
              .
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                <indexterm index="fn" number="790" mergedindex="cp">
                  \sqsupset
                </indexterm>
                \sqsupset
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <para>
              <u>
                2290
              </u>
              , Square superset symbol (relation). Similar: superset
Default handler: &nbsp;
              <code>
                \supset
              </code>
              . Not available in plain
Default handler: &tex;
              . In
Default handler: &latex;
               you need to load the
              <code>
                amssymb
              </code>
               package.
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                <indexterm index="fn" number="791" mergedindex="cp">
                  \sqsupseteq
                </indexterm>
                \sqsupseteq
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <para>
              <u>
                2292
              </u>
               Square superset or equal symbol (binary). Similar: superset or equal
Default handler: &nbsp;
              <code>
                \supseteq
              </code>
              .
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                <indexterm index="fn" number="792" mergedindex="cp">
                  \star
                </indexterm>
                \star
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <para>
              <u>
                22C6
              </u>
               Five-pointed star, sometimes used as a general binary operation but sometimes reserved for cross-correlation (binary). Similar: the synonyms asterisk
Default handler: &nbsp;
              <code>
                *
              </code>
               and
              <code>
                \ast
              </code>
              , which are six-pointed, and more often appear as a superscript or subscript, as with the Kleene star.
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                <indexterm index="fn" number="793" mergedindex="cp">
                  \subset
                </indexterm>
                \subset
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <para>
              <u>
                2282
              </u>
               Subset (occasionally, is implied by) (relation).
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                <indexterm index="fn" number="794" mergedindex="cp">
                  \subseteq
                </indexterm>
                \subseteq
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <para>
              <u>
                2286
              </u>
               Subset or equal to (relation).
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                <indexterm index="fn" number="795" mergedindex="cp">
                  \succ
                </indexterm>
                \succ
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <para>
              <u>
                227B
              </u>
               Comes after, succeeds (relation). Similar: is less than
Default handler: &nbsp;
              <code>
                >
              </code>
              .
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                <indexterm index="fn" number="796" mergedindex="cp">
                  \succeq
                </indexterm>
                \succeq
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <para>
              <u>
                2AB0
              </u>
               Succeeds or is equal to (relation). Similar: less than or equal to
Default handler: &nbsp;
              <code>
                \leq
              </code>
              .
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                <indexterm index="fn" number="797" mergedindex="cp">
                  \sum
                </indexterm>
                \sum
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <para>
              <u>
                2211
              </u>
               Summation (operator). Similar: Greek capital sigma
Default handler: &nbsp;
              <code>
                \Sigma
              </code>
              .
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                <indexterm index="fn" number="798" mergedindex="cp">
                  \supset
                </indexterm>
                \supset
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <para>
              <u>
                2283
              </u>
               Superset (relation).
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                <indexterm index="fn" number="799" mergedindex="cp">
                  \supseteq
                </indexterm>
                \supseteq
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <para>
              <u>
                2287
              </u>
               Superset or equal to (relation).
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                <indexterm index="fn" number="800" mergedindex="cp">
                  \surd
                </indexterm>
                \surd
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <para>
              <u>
                221A
              </u>
               Radical symbol (ordinary). The
Default handler: &latex;
               command
              <code>
                \sqrt
Default handler: &lbrace;
                ...
Default handler: &rbrace;
              </code>
               typesets the square root of the argument, with a bar that extends to cover the argument.
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                <indexterm index="fn" number="801" mergedindex="cp">
                  \swarrow
                </indexterm>
                \swarrow
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <para>
              <u>
                2199
              </u>
               Southwest-pointing arrow (relation).
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                <indexterm index="fn" number="802" mergedindex="cp">
                  \tau
                </indexterm>
                \tau
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <para>
              <u>
                03C4
              </u>
               Lowercase Greek letter (ordinary).
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                <indexterm index="fn" number="803" mergedindex="cp">
                  \theta
                </indexterm>
                \theta
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <para>
              <u>
                03B8
              </u>
               Lowercase Greek letter (ordinary). The variant form is
              <code>
                \vartheta
              </code>
Default handler: &nbsp;
              <u>
                03D1
              </u>
              .
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                <indexterm index="fn" number="804" mergedindex="cp">
                  \times
                </indexterm>
                \times
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <para>
              <u>
                00D7
              </u>
               Primary school multiplication sign (binary). See also
Default handler: &nbsp;
              <code>
                \cdot
              </code>
              .
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                <indexterm index="fn" number="805" mergedindex="cp">
                  \to
                </indexterm>
                \to
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <para>
              <u>
                2192
              </u>
               Right-pointing single line arrow (relation). Synonym:
Default handler: &nbsp;
              <code>
                \rightarrow
              </code>
              .
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                <indexterm index="fn" number="806" mergedindex="cp">
                  \top
                </indexterm>
                \top
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <para>
              <u>
                22A4
              </u>
               Top, greatest element of a partially ordered set (ordinary). See also
Default handler: &nbsp;
              <code>
                \bot
              </code>
              .
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                <indexterm index="fn" number="807" mergedindex="cp">
                  \triangle
                </indexterm>
                \triangle
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <para>
              <u>
                25B3
              </u>
               Triangle (ordinary).
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                <indexterm index="fn" number="808" mergedindex="cp">
                  \triangleleft
                </indexterm>
                \triangleleft
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <para>
              <u>
                25C1
              </u>
               Not-filled triangle pointing left (binary). Similar:
Default handler: &nbsp;
              <code>
                \lhd
              </code>
              . For the normal subgroup symbol you should load
              <code>
                amssymb
              </code>
               and use
Default handler: &nbsp;
              <code>
                \vartriangleleft
              </code>
               (which is a relation and so gives better spacing).
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                <indexterm index="fn" number="809" mergedindex="cp">
                  \triangleright
                </indexterm>
                \triangleright
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <para>
              <u>
                25B7
              </u>
               Not-filled triangle pointing right (binary). For the normal subgroup symbol you should instead load
              <code>
                amssymb
              </code>
               and use
Default handler: &nbsp;
              <code>
                \vartriangleright
              </code>
               (which is a relation and so gives better spacing).
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                <indexterm index="fn" number="810" mergedindex="cp">
                  \unlhd
                </indexterm>
                \unlhd
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <para>
              <u>
                22B4
              </u>
               Left-pointing not-filled underlined arrowhead, that is, triangle, with a line under (binary). For the normal subgroup symbol load
              <code>
                amssymb
              </code>
               and use
Default handler: &nbsp;
              <code>
                \vartrianglelefteq
              </code>
               (which is a relation and so gives better spacing).
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                <indexterm index="fn" number="811" mergedindex="cp">
                  \unrhd
                </indexterm>
                \unrhd
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <para>
              <u>
                22B5
              </u>
               Right-pointing not-filled underlined arrowhead, that is, triangle, with a line under (binary). For the normal subgroup symbol load
              <code>
                amssymb
              </code>
               and use
Default handler: &nbsp;
              <code>
                \vartrianglerighteq
              </code>
               (which is a relation and so gives better spacing).
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                <indexterm index="fn" number="812" mergedindex="cp">
                  \Uparrow
                </indexterm>
                \Uparrow
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <para>
              <u>
                21D1
              </u>
               Double-line upward-pointing arrow (relation). Similar: single-line up-pointing arrow
Default handler: &nbsp;
              <code>
                \uparrow
              </code>
              .
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                <indexterm index="fn" number="813" mergedindex="cp">
                  \uparrow
                </indexterm>
                \uparrow
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <para>
              <u>
                2191
              </u>
               Single-line upward-pointing arrow, diverges (relation). Similar: double-line up-pointing arrow
Default handler: &nbsp;
              <code>
                \Uparrow
              </code>
              .
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                <indexterm index="fn" number="814" mergedindex="cp">
                  \Updownarrow
                </indexterm>
                \Updownarrow
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <para>
              <u>
                21D5
              </u>
               Double-line upward-and-downward-pointing arrow (relation). Similar: single-line upward-and-downward-pointing arrow
Default handler: &nbsp;
              <code>
                \updownarrow
              </code>
              .
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                <indexterm index="fn" number="815" mergedindex="cp">
                  \updownarrow
                </indexterm>
                \updownarrow
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <para>
              <u>
                2195
              </u>
               Single-line upward-and-downward-pointing arrow (relation). Similar: double-line upward-and-downward-pointing arrow
Default handler: &nbsp;
              <code>
                \Updownarrow
              </code>
              .
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                <indexterm index="fn" number="816" mergedindex="cp">
                  \upharpoonright
                </indexterm>
                \upharpoonright
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <para>
              <u>
                21BE
              </u>
              , Up harpoon, with barb on right side (relation). Synonym:
Default handler: &nbsp;
              <codeDefault handler: &backslashchar;
>
                restriction
              </code>
              . Not available in plain
Default handler: &tex;
              . In
Default handler: &latex;
               you need to load the
              <code>
                amssymb
              </code>
               package.
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                <indexterm index="fn" number="817" mergedindex="cp">
                  \uplus
                </indexterm>
                \uplus
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <para>
              <u>
                228E
              </u>
               Multiset union, a union symbol with a plus symbol in the middle (binary). Similar: union
Default handler: &nbsp;
              <code>
                \cup
              </code>
              . Related: variable-sized operator
Default handler: &nbsp;
              <code>
                \biguplus
              </code>
              .
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                <indexterm index="fn" number="818" mergedindex="cp">
                  \Upsilon
                </indexterm>
                \Upsilon
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <para>
              <u>
                03A5
              </u>
               uppercase Greek letter (ordinary).
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                <indexterm index="fn" number="819" mergedindex="cp">
                  \upsilon
                </indexterm>
                \upsilon
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <para>
              <u>
                03C5
              </u>
               Lowercase Greek letter (ordinary).
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                <indexterm index="fn" number="820" mergedindex="cp">
                  \varepsilon
                </indexterm>
                \varepsilon
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <para>
              <u>
                03B5
              </u>
               Small letter script epsilon (ordinary). This is more widely used in mathematics than the non-variant lunate epsilon form
              <code>
                \epsilon
              </code>
Default handler: &nbsp;
              <u>
                03F5
              </u>
              . Related: set membership
Default handler: &nbsp;
              <code>
                \in
              </code>
              .
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                <indexterm index="fn" number="821" mergedindex="cp">
                  \vanothing
                </indexterm>
                \vanothing
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <para>
              <u>
                2205
              </u>
              , Empty set symbol. Similar:
              <code>
                \emptyset
              </code>
              . Related:
              <code>
                \revemptyset
              </code>
              . Not available in plain
Default handler: &tex;
              . In
Default handler: &latex;
               you need to load the
              <code>
                amssymb
              </code>
               package.
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                <indexterm index="fn" number="822" mergedindex="cp">
                  \varphi
                </indexterm>
                \varphi
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <para>
              <u>
                03C6
              </u>
               Variant on the lowercase Greek letter (ordinary). The non-variant form is
              <code>
                \phi
              </code>
Default handler: &nbsp;
              <u>
                03D5
              </u>
              .
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                <indexterm index="fn" number="823" mergedindex="cp">
                  \varpi
                </indexterm>
                \varpi
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <para>
              <u>
                03D6
              </u>
               Variant on the lowercase Greek letter (ordinary). The non-variant form is
              <code>
                \pi
              </code>
Default handler: &nbsp;
              <u>
                03C0
              </u>
              .
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                <indexterm index="fn" number="824" mergedindex="cp">
                  \varrho
                </indexterm>
                \varrho
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <para>
              <u>
                03F1
              </u>
               Variant on the lowercase Greek letter (ordinary). The non-variant form is
              <code>
                \rho
              </code>
Default handler: &nbsp;
              <u>
                03C1
              </u>
              .
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                <indexterm index="fn" number="825" mergedindex="cp">
                  \varsigma
                </indexterm>
                \varsigma
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <para>
              <u>
                03C2
              </u>
               Variant on the lowercase Greek letter (ordinary). The non-variant form is
              <code>
                \sigma
              </code>
Default handler: &nbsp;
              <u>
                03C3
              </u>
              .
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                <indexterm index="fn" number="826" mergedindex="cp">
                  \vartheta
                </indexterm>
                \vartheta
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <para>
              <u>
                03D1
              </u>
               Variant on the lowercase Greek letter (ordinary). The non-variant form is
              <code>
                \theta
              </code>
Default handler: &nbsp;
              <u>
                03B8
              </u>
              .
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                <indexterm index="fn" number="827" mergedindex="cp">
                  \vdash
                </indexterm>
                \vdash
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <para>
              <u>
                22A2
              </u>
               Provable; turnstile, vertical and a dash (relation). Similar: turnstile rotated a half-circle
Default handler: &nbsp;
              <code>
                \dashv
              </code>
              .
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                <indexterm index="fn" number="828" mergedindex="cp">
                  \vee
                </indexterm>
                \vee
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <para>
              <u>
                2228
              </u>
               Logical or; a downwards v shape (binary). Related: logical and
Default handler: &nbsp;
              <code>
                \wedge
              </code>
              . Similar: variable-sized operator
Default handler: &nbsp;
              <code>
                \bigvee
              </code>
              .
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                <indexterm index="fn" number="829" mergedindex="cp">
                  \Vert
                </indexterm>
                \Vert
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <para>
              <u>
                2016
              </u>
               Vertical double bar (ordinary).
              <xref label="Delimiters">
                <xrefnodename>
                  Delimiters
                </xrefnodename>
              </xref>
              , for how to use the
              <code>
                mathtools
              </code>
               package to create flexibly-sized norm symbols.
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                <indexterm index="fn" number="830" mergedindex="cp">
                  \vert
                </indexterm>
                \vert
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <para>
              <u>
                007C
              </u>
               Single line vertical bar (ordinary). For
Default handler: &textldquo;
              such that
Default handler: &textrdquo;
              , as in the definition of a set, use
Default handler: &nbsp;
              <code>
                \mid
              </code>
               because it is a relation.
              <xref label="Delimiters">
                <xrefnodename>
                  Delimiters
                </xrefnodename>
              </xref>
              , for how to use the
              <code>
                mathtools
              </code>
               package to create flexibly-sized absolute-value symbols.
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                <indexterm index="fn" number="831" mergedindex="cp">
                  \wedge
                </indexterm>
                \wedge
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <para>
              <u>
                2227
              </u>
               Logical and (binary). Synonym:
Default handler: &nbsp;
              <code>
                \land
              </code>
              . See also logical or
              <code>
                \vee
              </code>
              . Similar: variable-sized operator
Default handler: &nbsp;
              <code>
                \bigwedge
              </code>
              .
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                <indexterm index="fn" number="832" mergedindex="cp">
                  \wp
                </indexterm>
                \wp
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <para>
              <u>
                2118
              </u>
               Weierstrass p (ordinary).
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                <indexterm index="fn" number="833" mergedindex="cp">
                  \wr
                </indexterm>
                \wr
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <para>
              <u>
                2240
              </u>
               Wreath product (binary).
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                <indexterm index="fn" number="834" mergedindex="cp">
                  \Xi
                </indexterm>
                \Xi
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <para>
              <u>
                039E
              </u>
               uppercase Greek letter (ordinary).
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                <indexterm index="fn" number="835" mergedindex="cp">
                  \xi
                </indexterm>
                \xi
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <para>
              <u>
                03BE
              </u>
               Lowercase Greek letter (ordinary).
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                <indexterm index="fn" number="836" mergedindex="cp">
                  \zeta
                </indexterm>
                \zeta
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <para>
              <u>
                03B6
              </u>
               Lowercase Greek letter (ordinary).
            </para>
          </tableitem>
        </tableentry>
      </ftable>
      <para>
        The following symbols are most often used in plain text but
Default handler: &latex;
         provides versions to use in mathematical text.
      </para>
      <ftable commandarg="code" spaces=" " endspaces=" ">
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                <indexterm index="fn" number="837" mergedindex="cp">
                  \mathdollar
                </indexterm>
                \mathdollar
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <para>
              Dollar sign in math mode: $.
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                <indexterm index="fn" number="838" mergedindex="cp">
                  \mathparagraph
                </indexterm>
                \mathparagraph
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <para>
              Paragraph sign (pilcrow) in math mode,
              <u>
                00B6
              </u>
              .
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                <indexterm index="fn" number="839" mergedindex="cp">
                  \mathsection
                </indexterm>
                \mathsection
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <para>
              Section sign in math mode:
              <u>
                00A7
              </u>
              .
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                <indexterm index="fn" number="840" mergedindex="cp">
                  \mathsterling
                </indexterm>
                \mathsterling
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <para>
              Sterling sign in math mode:
Default handler: &pound;
              .
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                <indexterm index="fn" number="841" mergedindex="cp">
                  \mathunderscore
                </indexterm>
                \mathunderscore
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <para>
              Underscore in math mode: _.
            </para>
          </tableitem>
        </tableentry>
      </ftable>
      <menu endspaces=" ">
        <menuentry>
          <menuleadingtext>
            *
          </menuleadingtext>
          <menunode>
            Arrows
          </menunode>
          <menuseparator>
            ::
          </menuseparator>
          <menudescription>
            <pre xml:space="preserve">
              List of arrows.
            </pre>
          </menudescription>
        </menuentry>
        <menuentry>
          <menuleadingtext>
            *
          </menuleadingtext>
          <menunode>
            \boldmath
            &
             \unboldmath
          </menunode>
          <menuseparator>
            ::
          </menuseparator>
          <menudescription>
            <pre xml:space="preserve">
              Symbols in boldface.
            </pre>
          </menudescription>
        </menuentry>
        <menuentry>
          <menuleadingtext>
            *
          </menuleadingtext>
          <menunode>
            Blackboard bold
          </menunode>
          <menuseparator>
            ::
          </menuseparator>
          <menudescription>
            <pre xml:space="preserve">
              Doublestruck characters.
            </pre>
          </menudescription>
        </menuentry>
        <menuentry>
          <menuleadingtext>
            *
          </menuleadingtext>
          <menunode>
            Calligraphic
          </menunode>
          <menuseparator>
            ::
          </menuseparator>
          <menudescription>
            <pre xml:space="preserve">
              Cursive characters.
            </pre>
          </menudescription>
        </menuentry>
        <menuentry>
          <menuleadingtext>
            *
          </menuleadingtext>
          <menunode>
            Delimiters
          </menunode>
          <menuseparator>
            ::
          </menuseparator>
          <menudescription>
            <pre xml:space="preserve">
              Parentheses, braces, etc.
            </pre>
          </menudescription>
        </menuentry>
        <menuentry>
          <menuleadingtext>
            *
          </menuleadingtext>
          <menunode>
            Dots
          </menunode>
          <menuseparator>
            ::
          </menuseparator>
          <menudescription>
            <pre xml:space="preserve">
              Ellipses, etc.
            </pre>
          </menudescription>
        </menuentry>
        <menuentry>
          <menuleadingtext>
            *
          </menuleadingtext>
          <menunode>
            Greek letters
          </menunode>
          <menuseparator>
            ::
          </menuseparator>
          <menudescription>
            <pre xml:space="preserve">
              List of Greek letters.
            </pre>
          </menudescription>
        </menuentry>
      </menu>
      <node name="Arrows" spaces=" ">
        <nodename>
          Arrows
        </nodename>
        <nodenext automatic="on">
          \boldmath
          &
           \unboldmath
        </nodenext>
        <nodeup automatic="on">
          Math symbols
        </nodeup>
      </node>
      <subsection spaces=" ">
        <sectiontitle>
          Arrows
        </sectiontitle>
        <cindex index="cp" spaces=" ">
          <indexterm index="cp" number="661">
            arrows
          </indexterm>
        </cindex>
        <cindex index="cp" spaces=" ">
          <indexterm index="cp" number="662">
            symbols, arrows
          </indexterm>
        </cindex>
        <findex index="fn" spaces=" ">
          <indexterm index="fn" number="842" mergedindex="cp">
            math, arrows
          </indexterm>
        </findex>
        <cindex index="cp" spaces=" ">
          <indexterm index="cp" number="663">
            <r>
              package
            </r>
            ,
            <code>
              amsfonts
            </code>
          </indexterm>
        </cindex>
        <cindex index="cp" spaces=" ">
          <indexterm index="cp" number="664">
            <code>
              amsfonts
            </code>
            <r>
              package
            </r>
          </indexterm>
        </cindex>
        <cindex index="cp" spaces=" ">
          <indexterm index="cp" number="665">
            <r>
              package
            </r>
            ,
            <code>
              latexsym
            </code>
          </indexterm>
        </cindex>
        <cindex index="cp" spaces=" ">
          <indexterm index="cp" number="666">
            <code>
              latexsym
            </code>
            <r>
              package
            </r>
          </indexterm>
        </cindex>
        <para>
          These are the arrows that come with standard
Default handler: &latex;
          . The
          <code>
            latexsym
          </code>
           and
          <code>
            amsfonts
          </code>
           packages contain many more.
        </para>
        <multitable spaces=" " endspaces=" ">
          <columnfractions spaces=" " line=".10 .40 .50">
            <columnfraction value=".10"/>
            <columnfraction value=".40"/>
            <columnfraction value=".50"/>
          </columnfractions>
          <thead>
            <row>
              <entry command="headitem">
                <para>
                  Symbol
                </para>
              </entry>
              <entry command="tab">
                <para>
                  Command
                </para>
              </entry>
              <entry command="tab"/>
            </row>
          </thead>
          <tbody>
            <row>
              <entry command="item">
                <para>
                  <u>
                    021D3
                  </u>
                </para>
              </entry>
              <entry command="tab">
                <para>
                  <code>
                    \Downarrow
                  </code>
                </para>
              </entry>
              <entry command="tab"/>
            </row>
            <row>
              <entry command="item">
                <para>
                  <u>
                    02193
                  </u>
                </para>
              </entry>
              <entry command="tab">
                <para>
                  <code>
                    \downarrow
                  </code>
                </para>
              </entry>
              <entry command="tab"/>
            </row>
            <row>
              <entry command="item">
                <para>
                  <u>
                    021A9
                  </u>
                </para>
              </entry>
              <entry command="tab">
                <para>
                  <code>
                    \hookleftarrow
                  </code>
                </para>
              </entry>
              <entry command="tab"/>
            </row>
            <row>
              <entry command="item">
                <para>
                  <u>
                    021AA
                  </u>
                </para>
              </entry>
              <entry command="tab">
                <para>
                  <code>
                    \hookrightarrow
                  </code>
                </para>
              </entry>
              <entry command="tab"/>
            </row>
            <row>
              <entry command="item">
                <para>
                  <u>
                    2190
                  </u>
                </para>
              </entry>
              <entry command="tab">
                <para>
                  <code>
                    \leftarrow
                  </code>
                </para>
              </entry>
              <entry command="tab"/>
            </row>
            <row>
              <entry command="item">
                <para>
                  <u>
                    021D0
                  </u>
                </para>
              </entry>
              <entry command="tab">
                <para>
                  <code>
                    \Leftarrow
                  </code>
                </para>
              </entry>
              <entry command="tab"/>
            </row>
            <row>
              <entry command="item">
                <para>
                  <u>
                    021D4
                  </u>
                </para>
              </entry>
              <entry command="tab">
                <para>
                  <code>
                    \Leftrightarrow
                  </code>
                </para>
              </entry>
              <entry command="tab"/>
            </row>
            <row>
              <entry command="item">
                <para>
                  <u>
                    02194
                  </u>
                </para>
              </entry>
              <entry command="tab">
                <para>
                  <code>
                    \leftrightarrow
                  </code>
                </para>
              </entry>
              <entry command="tab"/>
            </row>
            <row>
              <entry command="item">
                <para>
                  <u>
                    027F5
                  </u>
                </para>
              </entry>
              <entry command="tab">
                <para>
                  <code>
                    \longleftarrow
                  </code>
                </para>
              </entry>
              <entry command="tab"/>
            </row>
            <row>
              <entry command="item">
                <para>
                  <u>
                    027F8
                  </u>
                </para>
              </entry>
              <entry command="tab">
                <para>
                  <code>
                    \Longleftarrow
                  </code>
                </para>
              </entry>
              <entry command="tab"/>
            </row>
            <row>
              <entry command="item">
                <para>
                  <u>
                    027F7
                  </u>
                </para>
              </entry>
              <entry command="tab">
                <para>
                  <code>
                    \longleftrightarrow
                  </code>
                </para>
              </entry>
              <entry command="tab"/>
            </row>
            <row>
              <entry command="item">
                <para>
                  <u>
                    027FA
                  </u>
                </para>
              </entry>
              <entry command="tab">
                <para>
                  <code>
                    \Longleftrightarrow
                  </code>
                </para>
              </entry>
              <entry command="tab"/>
            </row>
            <row>
              <entry command="item">
                <para>
                  <u>
                    027FC
                  </u>
                </para>
              </entry>
              <entry command="tab">
                <para>
                  <code>
                    \longmapsto
                  </code>
                </para>
              </entry>
              <entry command="tab"/>
            </row>
            <row>
              <entry command="item">
                <para>
                  <u>
                    027F9
                  </u>
                </para>
              </entry>
              <entry command="tab">
                <para>
                  <code>
                    \Longrightarrow
                  </code>
                </para>
              </entry>
              <entry command="tab"/>
            </row>
            <row>
              <entry command="item">
                <para>
                  <u>
                    027F6
                  </u>
                </para>
              </entry>
              <entry command="tab">
                <para>
                  <code>
                    \longrightarrow
                  </code>
                </para>
              </entry>
              <entry command="tab"/>
            </row>
            <row>
              <entry command="item">
                <para>
                  <u>
                    021A6
                  </u>
                </para>
              </entry>
              <entry command="tab">
                <para>
                  <code>
                    \mapsto
                  </code>
                </para>
              </entry>
              <entry command="tab"/>
            </row>
            <row>
              <entry command="item">
                <para>
                  <u>
                    02197
                  </u>
                </para>
              </entry>
              <entry command="tab">
                <para>
                  <code>
                    \nearrow
                  </code>
                </para>
              </entry>
              <entry command="tab"/>
            </row>
            <row>
              <entry command="item">
                <para>
                  <u>
                    02196
                  </u>
                </para>
              </entry>
              <entry command="tab">
                <para>
                  <code>
                    \nwarrow
                  </code>
                </para>
              </entry>
              <entry command="tab"/>
            </row>
            <row>
              <entry command="item">
                <para>
                  <u>
                    021D2
                  </u>
                </para>
              </entry>
              <entry command="tab">
                <para>
                  <code>
                    \Rightarrow
                  </code>
                </para>
              </entry>
              <entry command="tab"/>
            </row>
            <row>
              <entry command="item">
                <para>
                  <u>
                    02192
                  </u>
                </para>
              </entry>
              <entry command="tab">
                <para>
                  <code>
                    \rightarrow
                  </code>
                  , or
                  <code>
                    \to
                  </code>
                </para>
              </entry>
              <entry command="tab"/>
            </row>
            <row>
              <entry command="item">
                <para>
                  <u>
                    02198
                  </u>
                </para>
              </entry>
              <entry command="tab">
                <para>
                  <code>
                    \searrow
                  </code>
                </para>
              </entry>
              <entry command="tab"/>
            </row>
            <row>
              <entry command="item">
                <para>
                  <u>
                    02199
                  </u>
                </para>
              </entry>
              <entry command="tab">
                <para>
                  <code>
                    \swarrow
                  </code>
                </para>
              </entry>
              <entry command="tab"/>
            </row>
            <row>
              <entry command="item">
                <para>
                  <u>
                    02191
                  </u>
                </para>
              </entry>
              <entry command="tab">
                <para>
                  <code>
                    \uparrow
                  </code>
                </para>
              </entry>
              <entry command="tab"/>
            </row>
            <row>
              <entry command="item">
                <para>
                  <u>
                    021D1
                  </u>
                </para>
              </entry>
              <entry command="tab">
                <para>
                  <code>
                    \Uparrow
                  </code>
                </para>
              </entry>
              <entry command="tab"/>
            </row>
            <row>
              <entry command="item">
                <para>
                  <u>
                    02195
                  </u>
                </para>
              </entry>
              <entry command="tab">
                <para>
                  <code>
                    \updownarrow
                  </code>
                </para>
              </entry>
              <entry command="tab"/>
            </row>
            <row>
              <entry command="item">
                <para>
                  <u>
                    021D5
                  </u>
                </para>
              </entry>
              <entry command="tab">
                <para>
                  <code>
                    \Updownarrow
                  </code>
                </para>
              </entry>
              <entry command="tab"/>
            </row>
          </tbody>
        </multitable>
        <para>
          An example of the difference between
          <code>
            \to
          </code>
           and
          <code>
            \mapsto
          </code>
           is:
          <code>
            \( f\colon D\to C \) given by \( n\mapsto n^2 \)
          </code>
          .
        </para>
        <cindex index="cp" spaces=" ">
          <indexterm index="cp" number="667">
            <r>
              package
            </r>
            ,
            <code>
              amscd
            </code>
          </indexterm>
        </cindex>
        <cindex index="cp" spaces=" ">
          <indexterm index="cp" number="668">
            <code>
              amscd
            </code>
            <r>
              package
            </r>
          </indexterm>
        </cindex>
        <cindex index="cp" spaces=" ">
          <indexterm index="cp" number="669">
            <r>
              package
            </r>
            ,
            <code>
              tikz-cd
            </code>
          </indexterm>
        </cindex>
        <cindex index="cp" spaces=" ">
          <indexterm index="cp" number="670">
            <code>
              tikz-cd
            </code>
            <r>
              package
            </r>
          </indexterm>
        </cindex>
        <para>
          For commutative diagrams there are a number of packages, including
          <code>
            tikz-cd
          </code>
           and
          <code>
            amscd
          </code>
          .
        </para>
      </subsection>
      <node name="_005cboldmath-_0026-_005cunboldmath" spaces=" ">
        <nodename>
          \boldmath
          &
           \unboldmath
        </nodename>
        <nodenext automatic="on">
          Blackboard bold
        </nodenext>
        <nodeprev automatic="on">
          Arrows
        </nodeprev>
        <nodeup automatic="on">
          Math symbols
        </nodeup>
      </node>
      <subsection spaces=" ">
        <sectiontitle>
          <code>
            \boldmath
          </code>
          &
          <code>
            \unboldmath
          </code>
        </sectiontitle>
        <anchor name="_005cboldmath">
          \boldmath
        </anchor>
        <anchor name="_005cunboldmath">
          \unboldmath
        </anchor>
        <findex index="fn" spaces=" ">
          <indexterm index="fn" number="843" mergedindex="cp">
            \boldmath
          </indexterm>
        </findex>
        <findex index="fn" spaces=" ">
          <indexterm index="fn" number="844" mergedindex="cp">
            \unboldmath
          </indexterm>
        </findex>
        <cindex index="cp" spaces=" ">
          <indexterm index="cp" number="671">
            boldface mathematics
          </indexterm>
        </cindex>
        <cindex index="cp" spaces=" ">
          <indexterm index="cp" number="672">
            mathematics, boldface
          </indexterm>
        </cindex>
        <para>
          Synopsis (used in paragraph mode or LR mode):
        </para>
        <example endspaces=" ">
          <pre xml:space="preserve">
            \boldmath \(
            <var>
              math
            </var>
             \)
          </pre>
        </example>
        <noindent/>
        <para>
          or
        </para>
        <example endspaces=" ">
          <pre xml:space="preserve">
            \unboldmath \(
            <var>
              math
            </var>
             \)
          </pre>
        </example>
        <findex index="fn" spaces=" ">
          <indexterm index="fn" number="845" mergedindex="cp">
            \boldmath
          </indexterm>
        </findex>
        <findex index="fn" spaces=" ">
          <indexterm index="fn" number="846" mergedindex="cp">
            \unboldmath
          </indexterm>
        </findex>
        <para>
          Declarations to change the letters and symbols in
          <var>
            math
          </var>
           to be in a bold font, or to countermand that and bring back the regular (non-bold) default, respectively. They must be used when
          <emph>
            not
          </emph>
           in math mode or display math mode (
          <pxref label="Modes">
            <xrefnodename>
              Modes
            </xrefnodename>
          </pxref>
          ). Both commands are fragile (
          <pxref label="_005cprotect">
            <xrefnodename>
              \protect
            </xrefnodename>
          </pxref>
          ).
        </para>
        <para>
          In this example each
          <code>
            \boldmath
          </code>
           command takes place inside an
          <code>
            \mbox
          </code>
          ,
        </para>
        <example endspaces=" ">
          <pre xml:space="preserve">
            we have $\mbox
Default handler: &lbrace;
            \boldmath \( v \)
Default handler: &rbrace;
             = 5\cdot\mbox
Default handler: &lbrace;
            \boldmath \( u \)$
Default handler: &rbrace;
            $
          </pre>
        </example>
        <noindent/>
        <para>
          which means
          <code>
            \boldmath
          </code>
           is only called in a text mode, here LR mode, and explains why we must switch
Default handler: &latex;
           into math mode to set
          <code>
            v
          </code>
           and
          <code>
            u
          </code>
          .
        </para>
        <para>
          If you use either command inside math mode, as with
          <code>
            Trouble: \( \boldmath x \)
          </code>
          , then you get something like
          <samp>
            LaTeX Font Warning: Command \boldmath invalid in math mode
          </samp>
           and
          <samp>
            LaTeX Font Warning: Command \mathversion invalid in math mode
          </samp>
          .
        </para>
        <menu endspaces=" ">
          <menuentry>
            <menuleadingtext>
              *
            </menuleadingtext>
            <menunode>
              bm
            </menunode>
            <menuseparator>
              ::
            </menuseparator>
            <menudescription>
              <pre xml:space="preserve">
                The
                <code>
                  bm
                </code>
                 package for individual bold symbols.
              </pre>
            </menudescription>
          </menuentry>
          <menuentry>
            <menuleadingtext>
              *
            </menuleadingtext>
            <menunode>
              OpenType bold math
            </menunode>
            <menuseparator>
              ::
            </menuseparator>
            <menudescription>
              <pre xml:space="preserve">
                <code>
                  FakeBold
                </code>
                 or
                <code>
                  \symbf
                </code>
                .
              </pre>
            </menudescription>
          </menuentry>
        </menu>
        <node name="bm" spaces=" ">
          <nodename>
            bm
          </nodename>
          <nodenext automatic="on">
            OpenType bold math
          </nodenext>
          <nodeup automatic="on">
            \boldmath
            &
             \unboldmath
          </nodeup>
        </node>
        <subsubsection spaces=" ">
          <sectiontitle>
            <code>
              bm
            </code>
            : Individual bold math symbols
          </sectiontitle>
          <cindex index="cp" spaces=" ">
            <indexterm index="cp" number="673">
              <r>
                package
              </r>
              ,
              <code>
                bm
              </code>
            </indexterm>
          </cindex>
          <cindex index="cp" spaces=" ">
            <indexterm index="cp" number="674">
              <code>
                bm
              </code>
              <r>
                package
              </r>
            </indexterm>
          </cindex>
          <cindex index="cp" spaces=" ">
            <indexterm index="cp" number="675">
              symbols, boldface
            </indexterm>
          </cindex>
Default handler: <!-- c https://github.com/latex3/latex2e/issues/974 -->
          <para>
            Specifying
            <code>
              \boldmath
            </code>
             is the best method for typesetting a whole math expression in bold. But to typeset individual symbols within an expression in bold, the
            <code>
              bm
            </code>
             package provided by the
Default handler: &latex;
             Project team is better. Its usage is outside the scope of this document (see its documentation at
            <url>
              <urefurl>
                https://ctan.org/pkg/bm
              </urefurl>
            </url>
             or in your installation) but the spacing in the output of this small example will show that it is an improvement over
            <code>
              \boldmath
            </code>
             within an expression:
          </para>
          <example endspaces=" ">
            <pre xml:space="preserve">
              \usepackage
Default handler: &lbrace;
              bm
Default handler: &rbrace;
               % in preamble ... we have $\bm
Default handler: &lbrace;
              v
Default handler: &rbrace;
               = 5\cdot\bm
Default handler: &lbrace;
              u
Default handler: &rbrace;
              $
            </pre>
          </example>
        </subsubsection>
        <node name="OpenType-bold-math" spaces=" ">
          <nodename>
            OpenType bold math
          </nodename>
          <nodeprev automatic="on">
            bm
          </nodeprev>
          <nodeup automatic="on">
            \boldmath
            &
             \unboldmath
          </nodeup>
        </node>
        <subsubsection spaces=" ">
          <sectiontitle>
            OpenType bold math
          </sectiontitle>
          <cindex index="cp" spaces=" ">
            <indexterm index="cp" number="676">
              <r>
                package
              </r>
              ,
              <code>
                fontspec
              </code>
            </indexterm>
          </cindex>
          <cindex index="cp" spaces=" ">
            <indexterm index="cp" number="677">
              <code>
                fontspec
              </code>
              <r>
                package
              </r>
            </indexterm>
          </cindex>
          <para>
            Unfortunately, when using the Unicode engines (Xe
Default handler: &latex;
            , Lua
Default handler: &latex;
            ), neither
            <code>
              \boldmath
            </code>
             nor
            <code>
              bm
            </code>
             usually work well, because the OpenType math fonts normally used with those engines rarely come with a bold companion, and both
            <code>
              \boldmath
            </code>
             and
            <code>
              bm
            </code>
             require this. (The implementation of
            <code>
              bm
            </code>
             relies on
            <code>
              \boldmath
            </code>
            , so the requirements are the same.) If you do have a bold math font, though, then
            <code>
              \boldmath
            </code>
             and
            <code>
              bm
            </code>
             work fine.
          </para>
          <para>
            If no such font is available, one alternative is to construct fake bold fonts with the
            <code>
              fontspec
            </code>
             package
Default handler: &textrsquo;
            s
            <code>
              FakeBold=1
            </code>
             parameter (see its documentation,
            <url>
              <urefurl>
                https://ctan.org/pkg/fontspec
              </urefurl>
            </url>
            ). This may be acceptable for drafting or informal distribution, but the results are far from a true bold font.
          </para>
          <cindex index="cp" spaces=" ">
            <indexterm index="cp" number="678">
              <r>
                package
              </r>
              ,
              <code>
                unicode-math
              </code>
            </indexterm>
          </cindex>
          <cindex index="cp" spaces=" ">
            <indexterm index="cp" number="679">
              <code>
                unicode-math
              </code>
              <r>
                package
              </r>
            </indexterm>
          </cindex>
          <findex index="fn" spaces=" ">
            <indexterm index="fn" number="847" mergedindex="cp">
              \symbf
            </indexterm>
          </findex>
          <findex index="fn" spaces=" ">
            <indexterm index="fn" number="848" mergedindex="cp">
              \symbfit
            </indexterm>
          </findex>
          <para>
            Another alternative to handling bold for OpenType math fonts is to use the
            <code>
              \symbf
            </code>
             (bold),
            <code>
              \symbfit
            </code>
             (bold italic), and related commands from the
            <code>
              unicode-math
            </code>
             package. These do not change the current font, but rather change the (Unicode)
Default handler: &textldquo;
            alphabet
Default handler: &textrdquo;
             used, which in practice is more widely supported than a separate bold font. Many variations are possible, and so there are subtleties to getting the desired output. As usual, see the package documentation (
            <url>
              <urefurl>
                https://ctan.org/pkg/unicode-math
              </urefurl>
            </url>
            ).
          </para>
        </subsubsection>
      </subsection>
      <node name="Blackboard-bold" spaces=" ">
        <nodename>
          Blackboard bold
        </nodename>
        <nodenext automatic="on">
          Calligraphic
        </nodenext>
        <nodeprev automatic="on">
          \boldmath
          &
           \unboldmath
        </nodeprev>
        <nodeup automatic="on">
          Math symbols
        </nodeup>
      </node>
      <subsection spaces=" ">
        <sectiontitle>
          Blackboard bold
        </sectiontitle>
        <cindex index="cp" spaces=" ">
          <indexterm index="cp" number="680">
            blackboard bold
          </indexterm>
        </cindex>
        <cindex index="cp" spaces=" ">
          <indexterm index="cp" number="681">
            doublestruck
          </indexterm>
        </cindex>
        <para>
          Synopsis:
        </para>
        <example endspaces=" ">
          <pre xml:space="preserve">
            \usepackage
Default handler: &lbrace;
            amssymb
Default handler: &rbrace;
             % in preamble ... \mathbb
Default handler: &lbrace;
            <var>
              uppercase-letter
            </var>
Default handler: &rbrace;
          </pre>
        </example>
        <para>
          Provide blackboard bold symbols, sometimes also known as doublestruck letters, used to denote number sets such as the natural numbers, the integers, etc.
        </para>
        <para>
          Here
        </para>
        <example endspaces=" ">
          <pre xml:space="preserve">
            \( \forall n \in \mathbb
Default handler: &lbrace;
            N
Default handler: &rbrace;
            , n^2 \geq 0 \)
          </pre>
        </example>
        <noindent/>
        <para>
          the
          <code>
            \mathbb
Default handler: &lbrace;
            N
Default handler: &rbrace;
          </code>
           gives blackboard bold symbol
          <u>
            2115
          </u>
          , representing the natural numbers.
        </para>
        <para>
          If the argument contains something other than an uppercase letter, you do not get an error but you do get strange results, including unexpected characters.
        </para>
        <para>
          There are packages that give access to symbols other than just the capital letters; look on CTAN.
        </para>
      </subsection>
      <node name="Calligraphic" spaces=" ">
        <nodename>
          Calligraphic
        </nodename>
        <nodenext automatic="on">
          Delimiters
        </nodenext>
        <nodeprev automatic="on">
          Blackboard bold
        </nodeprev>
        <nodeup automatic="on">
          Math symbols
        </nodeup>
      </node>
      <subsection spaces=" ">
        <sectiontitle>
          Calligraphic
        </sectiontitle>
        <cindex index="cp" spaces=" ">
          <indexterm index="cp" number="682">
            calligraphic fonts
          </indexterm>
        </cindex>
        <cindex index="cp" spaces=" ">
          <indexterm index="cp" number="683">
            script fonts
          </indexterm>
        </cindex>
        <cindex index="cp" spaces=" ">
          <indexterm index="cp" number="684">
            fonts, script
          </indexterm>
        </cindex>
        <para>
          Synopsis:
        </para>
        <example endspaces=" ">
          <pre xml:space="preserve">
            \mathcal
Default handler: &lbrace;
            <var>
              uppercase-letters
            </var>
Default handler: &rbrace;
          </pre>
        </example>
        <para>
          Use a script-like font.
        </para>
        <para>
          In this example the graph identifier is output in a cursive font.
        </para>
        <example endspaces=" ">
          <pre xml:space="preserve">
            Let the graph be \( \mathcal
Default handler: &lbrace;
            G
Default handler: &rbrace;
             \).
          </pre>
        </example>
        <para>
          If you use something other than an uppercase letter then you do not get an error but you also do not get math calligraphic output. For instance,
          <code>
            \mathcal
Default handler: &lbrace;
            g
Default handler: &rbrace;
          </code>
           outputs a close curly brace symbol.
        </para>
      </subsection>
      <node name="Delimiters" spaces=" ">
        <nodename>
          Delimiters
        </nodename>
        <nodenext automatic="on">
          Dots
        </nodenext>
        <nodeprev automatic="on">
          Calligraphic
        </nodeprev>
        <nodeup automatic="on">
          Math symbols
        </nodeup>
      </node>
      <subsection spaces=" ">
        <sectiontitle>
          Delimiters
        </sectiontitle>
        <cindex index="cp" spaces=" ">
          <indexterm index="cp" number="685">
            delimiters
          </indexterm>
        </cindex>
        <cindex index="cp" spaces=" ">
          <indexterm index="cp" number="686">
            parentheses
          </indexterm>
        </cindex>
        <cindex index="cp" spaces=" ">
          <indexterm index="cp" number="687">
            braces
          </indexterm>
        </cindex>
        <cindex index="cp" spaces=" ">
          <indexterm index="cp" number="688">
            curly braces
          </indexterm>
        </cindex>
        <cindex index="cp" spaces=" ">
          <indexterm index="cp" number="689">
            brackets
          </indexterm>
        </cindex>
        <para>
          Delimiters are parentheses, braces, or other characters used to mark the start and end of subformulas. This formula has three sets of parentheses delimiting the three subformulas.
        </para>
        <example endspaces=" ">
          <pre xml:space="preserve">
            (z-z_0)^2 = (x-x_0)^2 + (y-y_0)^2
          </pre>
        </example>
        <noindent/>
        <para>
          The delimiters do not need to match, so you can enter
          <code>
            \( [0,1) \)
          </code>
          .
        </para>
        <para>
          Here are the common delimiters:
        </para>
        <multitable spaces=" " endspaces=" ">
          <columnfractions spaces=" " line=".11 .20 .40 .29">
            <columnfraction value=".11"/>
            <columnfraction value=".20"/>
            <columnfraction value=".40"/>
            <columnfraction value=".29"/>
          </columnfractions>
          <thead>
            <row>
              <entry command="headitem">
                <para>
                  Delimiter
                </para>
              </entry>
              <entry command="tab">
                <para>
                  Command
                </para>
              </entry>
              <entry command="tab">
                <para>
                  Name
                </para>
              </entry>
            </row>
          </thead>
          <tbody>
            <row>
              <entry command="item">
                <para>
                  (
                </para>
              </entry>
              <entry command="tab">
                <para>
                  <code>
                    (
                  </code>
                </para>
              </entry>
              <entry command="tab">
                <para>
                  Left parenthesis
                </para>
              </entry>
            </row>
            <row>
              <entry command="item">
                <para>
                  )
                </para>
              </entry>
              <entry command="tab">
                <para>
                  <code>
                    )
                  </code>
                </para>
              </entry>
              <entry command="tab">
                <para>
                  Right parenthesis
                </para>
              </entry>
            </row>
            <row>
              <entry command="item">
                <para>
                  \
Default handler: &rbrace;
                </para>
              </entry>
              <entry command="tab">
                <para>
                  <codeDefault handler: &lbrace;
/>
                   or
                  <code>
                    \lbrace
                  </code>
                </para>
              </entry>
              <entry command="tab">
                <para>
                  Left brace
                </para>
              </entry>
            </row>
            <row>
              <entry command="item">
                <para>
                  \
Default handler: &lbrace;
                </para>
              </entry>
              <entry command="tab">
                <para>
                  <codeDefault handler: &rbrace;
/>
                   or
                  <code>
                    \rbrace
                  </code>
                </para>
              </entry>
              <entry command="tab">
                <para>
                  Right brace
                </para>
              </entry>
            </row>
            <row>
              <entry command="item">
                <para>
                  [
                </para>
              </entry>
              <entry command="tab">
                <para>
                  <code>
                    [
                  </code>
                   or
                  <code>
                    \lbrack
                  </code>
                </para>
              </entry>
              <entry command="tab">
                <para>
                  Left bracket
                </para>
              </entry>
            </row>
            <row>
              <entry command="item">
                <para>
                  ]
                </para>
              </entry>
              <entry command="tab">
                <para>
                  <code>
                    ]
                  </code>
                   or
                  <code>
                    \rbrack
                  </code>
                </para>
              </entry>
              <entry command="tab">
                <para>
                  Right bracket
                </para>
              </entry>
            </row>
            <row>
              <entry command="item">
                <para>
                  <u>
                    230A
                  </u>
                </para>
              </entry>
              <entry command="tab">
                <para>
                  <code>
                    \lfloor
                  </code>
                </para>
              </entry>
              <entry command="tab">
                <para>
                  Left floor bracket
                </para>
              </entry>
            </row>
            <row>
              <entry command="item">
                <para>
                  <u>
                    230B
                  </u>
                </para>
              </entry>
              <entry command="tab">
                <para>
                  <code>
                    \rfloor
                  </code>
                </para>
              </entry>
              <entry command="tab">
                <para>
                  Right floor bracket
                </para>
              </entry>
            </row>
            <row>
              <entry command="item">
                <para>
                  <u>
                    2308
                  </u>
                </para>
              </entry>
              <entry command="tab">
                <para>
                  <code>
                    \lceil
                  </code>
                </para>
              </entry>
              <entry command="tab">
                <para>
                  Left ceiling bracket
                </para>
              </entry>
            </row>
            <row>
              <entry command="item">
                <para>
                  <u>
                    2309
                  </u>
                </para>
              </entry>
              <entry command="tab">
                <para>
                  <code>
                    \rceil
                  </code>
                </para>
              </entry>
              <entry command="tab">
                <para>
                  Right ceiling bracket
                </para>
              </entry>
            </row>
            <row>
              <entry command="item">
                <para>
                  <u>
                    27E8
                  </u>
                </para>
              </entry>
              <entry command="tab">
                <para>
                  <code>
                    \langle
                  </code>
                </para>
              </entry>
              <entry command="tab">
                <para>
                  Left angle bracket
                </para>
              </entry>
            </row>
            <row>
              <entry command="item">
                <para>
                  <u>
                    27E9
                  </u>
                </para>
              </entry>
              <entry command="tab">
                <para>
                  <code>
                    \rangle
                  </code>
                </para>
              </entry>
              <entry command="tab">
                <para>
                  Right angle bracket
                </para>
              </entry>
            </row>
            <row>
              <entry command="item">
                <para>
                  /
                </para>
              </entry>
              <entry command="tab">
                <para>
                  <code>
                    /
                  </code>
                </para>
              </entry>
              <entry command="tab">
                <para>
                  Slash, or forward slash
                </para>
              </entry>
            </row>
            <row>
              <entry command="item">
                <para>
                  \
                </para>
              </entry>
              <entry command="tab">
                <para>
                  <code>
                    \backslash
                  </code>
                </para>
              </entry>
              <entry command="tab">
                <para>
                  Reverse slash, or backslash
                </para>
              </entry>
            </row>
            <row>
              <entry command="item">
                <para>
                  |
                </para>
              </entry>
              <entry command="tab">
                <para>
                  <code>
                    |
                  </code>
                   or
                  <code>
                    \vert
                  </code>
                </para>
              </entry>
              <entry command="tab">
                <para>
                  Vertical bar
                </para>
              </entry>
            </row>
            <row>
              <entry command="item">
                <para>
                  <u>
                    2016
                  </u>
                </para>
              </entry>
              <entry command="tab">
                <para>
                  <code>
                    \|
                  </code>
                   or
                  <code>
                    \Vert
                  </code>
                </para>
              </entry>
              <entry command="tab">
                <para>
                  Double vertical bar
                </para>
              </entry>
            </row>
          </tbody>
        </multitable>
        <cindex index="cp" spaces=" ">
          <indexterm index="cp" number="690">
            <r>
              package
            </r>
            ,
            <code>
              mathtools
            </code>
          </indexterm>
        </cindex>
        <cindex index="cp" spaces=" ">
          <indexterm index="cp" number="691">
            <code>
              mathtools
            </code>
            <r>
              package
            </r>
          </indexterm>
        </cindex>
        <para>
          The
          <code>
            mathtools
          </code>
           package allows you to create commands for paired delimiters. For instance, if you put
          <code>
            \DeclarePairedDelimiter\abs
Default handler: &lbrace;
            \lvert
Default handler: &rbrace;
Default handler: &lbrace;
            \rvert
Default handler: &rbrace;
          </code>
           in your preamble then you get two commands for single-line vertical bars (they only work in math mode). The starred form, such as
          <code>
            \abs*
Default handler: &lbrace;
            \frac
Default handler: &lbrace;
            22
Default handler: &rbrace;
Default handler: &lbrace;
            7
Default handler: &rbrace;
Default handler: &rbrace;
          </code>
          , has the height of the vertical bars match the height of the argument. The unstarred form, such as
          <code>
            \abs
Default handler: &lbrace;
            \frac
Default handler: &lbrace;
            22
Default handler: &rbrace;
Default handler: &lbrace;
            7
Default handler: &rbrace;
Default handler: &rbrace;
          </code>
          , has the bars fixed at a default height. This form accepts an optional argument, as in
          <code>
            \abs[
            <var>
              size command
            </var>
            ]
Default handler: &lbrace;
            \frac
Default handler: &lbrace;
            22
Default handler: &rbrace;
Default handler: &lbrace;
            7
Default handler: &rbrace;
Default handler: &rbrace;
          </code>
          , where the height of the bars is given in
          <var>
            size command
          </var>
          , such as
          <code>
            \Bigg
          </code>
          . Using instead
          <code>
            \lVert
          </code>
           and
          <code>
            \rVert
          </code>
           as the symbols will give you a norm symbol with the same behavior.
        </para>
        <menu endspaces=" ">
          <menuentry>
            <menuleadingtext>
              *
            </menuleadingtext>
            <menunode>
              \left
              &
               \right
            </menunode>
            <menuseparator>
              ::
            </menuseparator>
            <menudescription>
              <pre xml:space="preserve">
                Automatically sized delimiters.
              </pre>
            </menudescription>
          </menuentry>
          <menuentry>
            <menuleadingtext>
              *
            </menuleadingtext>
            <menunode>
              \bigl
              &
               \bigr etc.
            </menunode>
            <menuseparator>
              ::
            </menuseparator>
            <menudescription>
              <pre xml:space="preserve">
                Manually sized delimiters.
              </pre>
            </menudescription>
          </menuentry>
        </menu>
        <node name="_005cleft-_0026-_005cright" spaces=" ">
          <nodename>
            \left
            &
             \right
          </nodename>
          <nodenext automatic="on">
            \bigl
            &
             \bigr etc.
          </nodenext>
          <nodeup automatic="on">
            Delimiters
          </nodeup>
        </node>
        <subsubsection spaces=" ">
          <sectiontitle>
            <code>
              \left
            </code>
            &
            <code>
              \right
            </code>
          </sectiontitle>
          <anchor name="_005cleft">
            \left
          </anchor>
          <anchor name="_005cright">
            \right
          </anchor>
          <findex index="fn" spaces=" ">
            <indexterm index="fn" number="849" mergedindex="cp">
              \left
            </indexterm>
          </findex>
          <findex index="fn" spaces=" ">
            <indexterm index="fn" number="850" mergedindex="cp">
              \right
            </indexterm>
          </findex>
          <cindex index="cp" spaces=" ">
            <indexterm index="cp" number="692">
              delimiters, paired
            </indexterm>
          </cindex>
          <cindex index="cp" spaces=" ">
            <indexterm index="cp" number="693">
              paired delimiters
            </indexterm>
          </cindex>
          <cindex index="cp" spaces=" ">
            <indexterm index="cp" number="694">
              matching parentheses
            </indexterm>
          </cindex>
          <cindex index="cp" spaces=" ">
            <indexterm index="cp" number="695">
              matching brackets
            </indexterm>
          </cindex>
          <cindex index="cp" spaces=" ">
            <indexterm index="cp" number="696">
              null delimiter
            </indexterm>
          </cindex>
Default handler: <!-- c Credit: SE userPhilipp https://tex.stackexchange.com/a/12793 -->
          <para>
            Synopsis:
          </para>
          <example endspaces=" ">
            <pre xml:space="preserve">
              \left
              <var>
                delimiter1
              </var>
               ... \right
              <var>
                delimiter2
              </var>
            </pre>
          </example>
          <para>
            Make matching parentheses, braces, or other delimiters.
Default handler: &latex;
             makes the delimiters tall enough to just cover the size of the formula that they enclose.
          </para>
          <para>
            This makes a unit vector surrounded by parentheses tall enough to cover the entries.
          </para>
          <example endspaces=" ">
            <pre xml:space="preserve">
              \begin
Default handler: &lbrace;
              equation
Default handler: &rbrace;
               \left(\begin
Default handler: &lbrace;
              array
Default handler: &rbrace;
Default handler: &lbrace;
              c
Default handler: &rbrace;
               1 \\ 0 \\ \end
Default handler: &lbrace;
              array
Default handler: &rbrace;
              \right) \end
Default handler: &lbrace;
              equation
Default handler: &rbrace;
            </pre>
          </example>
          <para>
            <xref label="Delimiters">
              <xrefnodename>
                Delimiters
              </xrefnodename>
            </xref>
            , for a list of the common delimiters.
          </para>
          <para>
            Every
            <code>
              \left
            </code>
             must have a matching
            <code>
              \right
            </code>
            . In the above example, leaving out the
            <code>
              \left(
            </code>
             gets the error message
            <samp>
              Extra \right
            </samp>
            . Leaving out the
            <code>
              \right)
            </code>
             gets
            <samp>
              You can't use `\eqno' in math mode
            </samp>
            .
          </para>
          <cindex index="cp" spaces=" ">
            <indexterm index="cp" number="697">
              <r>
                package
              </r>
              ,
              <code>
                amsmath
              </code>
            </indexterm>
          </cindex>
          <cindex index="cp" spaces=" ">
            <indexterm index="cp" number="698">
              <code>
                amsmath
              </code>
              <r>
                package
              </r>
            </indexterm>
          </cindex>
          <cindex index="cp" spaces=" ">
            <indexterm index="cp" number="699">
              <r>
                package
              </r>
              ,
              <code>
                mathtools
              </code>
            </indexterm>
          </cindex>
          <cindex index="cp" spaces=" ">
            <indexterm index="cp" number="700">
              <code>
                mathtools
              </code>
              <r>
                package
              </r>
            </indexterm>
          </cindex>
          <para>
            However,
            <var>
              delimiter1
            </var>
             and
            <var>
              delimiter2
            </var>
             need not match. A common case is that you want an unmatched brace, as below. Use a period,
            <samp>
              .
            </samp>
            , as a
            <dfn>
              null delimiter
            </dfn>
            .
          </para>
          <example endspaces=" ">
            <pre xml:space="preserve">
              \begin
Default handler: &lbrace;
              equation
Default handler: &rbrace;
               f(n)=\left\
Default handler: &lbrace;
              \begin
Default handler: &lbrace;
              array
Default handler: &rbrace;
Default handler: &lbrace;
              ll
Default handler: &rbrace;
               1
              &
              \mbox
Default handler: &lbrace;
              --if \(n=0\)
Default handler: &rbrace;
               \\ f(n-1)+3n^2
              &
              \mbox
Default handler: &lbrace;
              --else
Default handler: &rbrace;
               \end
Default handler: &lbrace;
              array
Default handler: &rbrace;
              \right. \end
Default handler: &lbrace;
              equation
Default handler: &rbrace;
            </pre>
          </example>
          <noindent/>
          <para>
            Note that to get a curly brace as a delimiter you must prefix it with a backslash,
            <code>
              \
Default handler: &lbrace;
            </code>
             (
            <pxref label="Reserved-characters">
              <xrefnodename>
                Reserved characters
              </xrefnodename>
            </pxref>
            ). (The packages
            <code>
              amsmath
            </code>
             and
            <code>
              mathtools
            </code>
             allow you to get the above construct through in a
            <code>
              cases
            </code>
             environment.)
          </para>
          <para>
            The
            <code>
              \left ... \right
            </code>
             pair make a group. One consequence is that the formula enclosed in the
            <code>
              \left ... \right
            </code>
             pair cannot have line breaks in the output. This includes both manual line breaks and
Default handler: &latex;
            -generated automatic ones. In this example,
Default handler: &latex;
             breaks the equation to make the formula fit the margins.
          </para>
          <example endspaces=" ">
            <pre xml:space="preserve">
              Lorem ipsum dolor sit amet \( (a+b+c+d+e+f+g+h+i+j+k+l+m+n+o+p+q+r+s+t+u+v+w+x+y+z) \)
            </pre>
          </example>
          <noindent/>
          <para>
            But with
            <code>
              \left
            </code>
             and
            <code>
              \right
            </code>
          </para>
          <example endspaces=" ">
            <pre xml:space="preserve">
              Lorem ipsum dolor sit amet \( \left(a+b+c+d+e+f+g+h+i+j+k+l+m+n+o+p+q+r+s+t+u+v+w+x+y+z\right) \)
            </pre>
          </example>
          <noindent/>
          <paraDefault handler: &latex;
>
             won
Default handler: &textrsquo;
            t break the line, causing the formula to extend into the margin.
          </para>
          <para>
            Because
            <code>
              \left ... \right
            </code>
             make a group, all the usual grouping rules hold. Here, the value of
            <code>
              \testlength
            </code>
             set inside the equation will be forgotten, and the output is
            <samp>
              1.2pt
            </samp>
            .
          </para>
          <example endspaces=" ">
            <pre xml:space="preserve">
              \newlength
Default handler: &lbrace;
              \testlength
Default handler: &rbrace;
               \setlength
Default handler: &lbrace;
              \testlength
Default handler: &rbrace;
Default handler: &lbrace;
              1.2pt
Default handler: &rbrace;
               \begin
Default handler: &lbrace;
              equation
Default handler: &rbrace;
               \left( a+b=c \setlength
Default handler: &lbrace;
              \testlength
Default handler: &rbrace;
Default handler: &lbrace;
              3.4pt
Default handler: &rbrace;
               \right) \the\testlength \end
Default handler: &lbrace;
              equation
Default handler: &rbrace;
            </pre>
          </example>
          <para>
            The
            <code>
              \left ... \right
            </code>
             pair affect the horizontal spacing of the enclosed formula, in two ways. The first is that in
            <code>
              \( \sin(x) = \sin\left(x\right) \)
            </code>
             the one after the equals sign has more space around the
            <code>
              x
            </code>
            . That
Default handler: &textrsquo;
            s because
            <code>
              \left( ... \right)
            </code>
             inserts an inner node while
            <code>
              ( ... )
            </code>
             inserts an opening node. The second way that the pair affect the horizontal spacing is that because they form a group, the enclosed subformula will be typeset at its natural width, with no stretching or shrinking to make the line fit better.
          </para>
          <paraDefault handler: &tex;
>
             scales the delimiters according to the height and depth of the enclosed formula. Here
Default handler: &latex;
             grows the brackets to extend the full height of the integral.
          </para>
          <example endspaces=" ">
            <pre xml:space="preserve">
              \begin
Default handler: &lbrace;
              equation
Default handler: &rbrace;
               \left[ \int_
Default handler: &lbrace;
              x=r_0
Default handler: &rbrace;
              ^
Default handler: &lbrace;
              \infty
Default handler: &rbrace;
               -G\frac
Default handler: &lbrace;
              Mm
Default handler: &rbrace;
Default handler: &lbrace;
              r^2
Default handler: &rbrace;
              \, dr \right] \end
Default handler: &lbrace;
              equation
Default handler: &rbrace;
            </pre>
          </example>
          <para>
            Manual sizing is often better. For instance, although below the rule has no depth,
Default handler: &tex;
             will create delimiters that extend far below the rule.
          </para>
          <example endspaces=" ">
            <pre xml:space="preserve">
              \begin
Default handler: &lbrace;
              equation
Default handler: &rbrace;
               \left( \rule
Default handler: &lbrace;
              1pt
Default handler: &rbrace;
Default handler: &lbrace;
              1cm
Default handler: &rbrace;
               \right) \end
Default handler: &lbrace;
              equation
Default handler: &rbrace;
            </pre>
          </example>
          <noindent/>
          <paraDefault handler: &tex;
>
             can choose delimiters that are too small, as in
            <code>
              \( \left| |x|+|y| \right| \)
            </code>
            . It can also choose delimiters that are too large, as here.
          </para>
          <example endspaces=" ">
            <pre xml:space="preserve">
              \begin
Default handler: &lbrace;
              equation
Default handler: &rbrace;
               \left( \sum_
Default handler: &lbrace;
              0\leq i
              <
              n
Default handler: &rbrace;
               i^k \right) \end
Default handler: &lbrace;
              equation
Default handler: &rbrace;
            </pre>
          </example>
          <noindent/>
          <para>
            A third awkward case is when a long displayed formula is on more than one line and you must match the sizes of the opening and closing delimiter; you can
Default handler: &textrsquo;
            t use
            <code>
              \left
            </code>
             on the first line and
            <code>
              \right
            </code>
             on the last because they must be paired.
          </para>
          <para>
            To size the delimiters manually, see
Default handler: &nbsp;
            <ref label="_005cbigl-_0026-_005cbigr-etc_002e">
              <xrefnodename>
                \bigl
                &
                 \bigr etc.
              </xrefnodename>
            </ref>
            .
          </para>
        </subsubsection>
        <node name="_005cbigl-_0026-_005cbigr-etc_002e" spaces=" ">
          <nodename>
            \bigl
            &
             \bigr etc.
          </nodename>
          <nodeprev automatic="on">
            \left
            &
             \right
          </nodeprev>
          <nodeup automatic="on">
            Delimiters
          </nodeup>
        </node>
        <subsubsection spaces=" ">
          <sectiontitle>
            <code>
              \bigl
            </code>
            ,
            <code>
              \bigr
            </code>
            , etc.
          </sectiontitle>
          <anchor name="_005cbigl">
            \bigl
          </anchor>
          <anchor name="_005cbigr">
            \bigr
          </anchor>
          <findex index="fn" spaces=" ">
            <indexterm index="fn" number="851" mergedindex="cp">
              \bigl
            </indexterm>
          </findex>
          <findex index="fn" spaces=" ">
            <indexterm index="fn" number="852" mergedindex="cp">
              \bigr
            </indexterm>
          </findex>
          <para>
            Synopsis, one of:
          </para>
          <example endspaces=" ">
            <pre xml:space="preserve">
              \bigl
              <inlinefmt>
                <inlinefmtformat>
                  info
                </inlinefmtformat>
                <inlinefmtcontent>
                  @tie{}
                </inlinefmtcontent>
              </inlinefmt>
              <var>
                delimiter1
              </var>
               ... \bigr
              <inlinefmt>
                <inlinefmtformat>
                  info
                </inlinefmtformat>
                <inlinefmtcontent>
                  @tie{}
                </inlinefmtcontent>
              </inlinefmt>
              <var>
                delimiter2
              </var>
               \Bigl
              <inlinefmt>
                <inlinefmtformat>
                  info
                </inlinefmtformat>
                <inlinefmtcontent>
                  @tie{}
                </inlinefmtcontent>
              </inlinefmt>
              <var>
                delimiter1
              </var>
               ... \bigr
              <inlinefmt>
                <inlinefmtformat>
                  info
                </inlinefmtformat>
                <inlinefmtcontent>
                  @tie{}
                </inlinefmtcontent>
              </inlinefmt>
              <var>
                delimiter2
              </var>
               \biggl
              <inlinefmt>
                <inlinefmtformat>
                  info
                </inlinefmtformat>
                <inlinefmtcontent>
                  @tie{}
                </inlinefmtcontent>
              </inlinefmt>
              <var>
                delimiter1
              </var>
               ... \biggr
              <inlinefmt>
                <inlinefmtformat>
                  info
                </inlinefmtformat>
                <inlinefmtcontent>
                  @tie{}
                </inlinefmtcontent>
              </inlinefmt>
              <var>
                delimiter2
              </var>
               \Biggl
              <inlinefmt>
                <inlinefmtformat>
                  info
                </inlinefmtformat>
                <inlinefmtcontent>
                  @tie{}
                </inlinefmtcontent>
              </inlinefmt>
              <var>
                delimiter1
              </var>
               ... \Biggr
              <inlinefmt>
                <inlinefmtformat>
                  info
                </inlinefmtformat>
                <inlinefmtcontent>
                  @tie{}
                </inlinefmtcontent>
              </inlinefmt>
              <var>
                delimiter2
              </var>
            </pre>
          </example>
          <noindent/>
          <para>
            (as with
            <code>
              \bigl[...\bigr]
            </code>
            ; strictly speaking they need not be paired, see below), or one of:
          </para>
          <example endspaces=" ">
            <pre xml:space="preserve">
              \bigm
              <inlinefmt>
                <inlinefmtformat>
                  info
                </inlinefmtformat>
                <inlinefmtcontent>
                  @tie{}
                </inlinefmtcontent>
              </inlinefmt>
              <var>
                delimiter
              </var>
               \Bigm
              <inlinefmt>
                <inlinefmtformat>
                  info
                </inlinefmtformat>
                <inlinefmtcontent>
                  @tie{}
                </inlinefmtcontent>
              </inlinefmt>
              <var>
                delimiter
              </var>
               \biggm
              <inlinefmt>
                <inlinefmtformat>
                  info
                </inlinefmtformat>
                <inlinefmtcontent>
                  @tie{}
                </inlinefmtcontent>
              </inlinefmt>
              <var>
                delimiter
              </var>
               \Biggm
              <inlinefmt>
                <inlinefmtformat>
                  info
                </inlinefmtformat>
                <inlinefmtcontent>
                  @tie{}
                </inlinefmtcontent>
              </inlinefmt>
              <var>
                delimiter
              </var>
            </pre>
          </example>
          <noindent/>
          <para>
            (as with
            <code>
              \bigm|
            </code>
            ), or one of:
          </para>
          <example endspaces=" ">
            <pre xml:space="preserve">
              \big
              <inlinefmt>
                <inlinefmtformat>
                  info
                </inlinefmtformat>
                <inlinefmtcontent>
                  @tie{}
                </inlinefmtcontent>
              </inlinefmt>
              <var>
                delimiter
              </var>
               \Big
              <inlinefmt>
                <inlinefmtformat>
                  info
                </inlinefmtformat>
                <inlinefmtcontent>
                  @tie{}
                </inlinefmtcontent>
              </inlinefmt>
              <var>
                delimiter
              </var>
               \bigg
              <inlinefmt>
                <inlinefmtformat>
                  info
                </inlinefmtformat>
                <inlinefmtcontent>
                  @tie{}
                </inlinefmtcontent>
              </inlinefmt>
              <var>
                delimiter
              </var>
               \Bigg
              <inlinefmt>
                <inlinefmtformat>
                  info
                </inlinefmtformat>
                <inlinefmtcontent>
                  @tie{}
                </inlinefmtcontent>
              </inlinefmt>
              <var>
                delimiter
              </var>
            </pre>
          </example>
          <noindent/>
          <para>
            (as with
            <code>
              \big[
            </code>
            ).
          </para>
          <para>
            Produce manually-sized delimiters. For delimiters that are automatically sized see
Default handler: &nbsp;
            <ref label="_005cleft-_0026-_005cright">
              <xrefnodename>
                \left
                &
                 \right
              </xrefnodename>
            </ref>
            ).
          </para>
          <para>
            This produces slightly larger outer vertical bars.
          </para>
          <example endspaces=" ">
            <pre xml:space="preserve">
               \bigl| |x|+|y| \bigr|
            </pre>
          </example>
          <para>
            The commands above are listed in order of increasing size. You can use the smallest size such as
            <code>
              \bigl...\bigr
            </code>
             in a paragraph without causing
Default handler: &latex;
             to spread the lines apart. The larger sizes are meant for displayed equations.
          </para>
          <para>
            <xref label="Delimiters">
              <xrefnodename>
                Delimiters
              </xrefnodename>
            </xref>
            , for a list of the common delimiters. In the family of commands with
            <samp>
              l
            </samp>
             or
Default handler: &nbsp;
            <samp>
              r
            </samp>
            ,
            <var>
              delimiter1
            </var>
             and
            <var>
              delimiter2
            </var>
             need not match together.
          </para>
          <para>
            The
            <samp>
              l
            </samp>
             and
            <samp>
              r
            </samp>
             commands produce open and close delimiters that insert no horizontal space between a preceding atom and the delimiter, while the commands without
            <samp>
              l
            </samp>
             and
            <samp>
              r
            </samp>
             insert some space (because each delimiter is set as an ordinary variable). Compare these two.
          </para>
Default handler: <!-- c credit: Martin Heller https://tex.stackexchange.com/a/1234 -->
          <example endspaces=" ">
            <pre xml:space="preserve">
              \begin
Default handler: &lbrace;
              tabular
Default handler: &rbrace;
Default handler: &lbrace;
              l
Default handler: &rbrace;
               \(\displaystyle \sin\biggl(\frac
Default handler: &lbrace;
              1
Default handler: &rbrace;
Default handler: &lbrace;
              2
Default handler: &rbrace;
              \biggr) \) \\ % good \(\displaystyle \sin\bigg(\frac
Default handler: &lbrace;
              1
Default handler: &rbrace;
Default handler: &lbrace;
              2
Default handler: &rbrace;
              \bigg) \) \\ % bad \end
Default handler: &lbrace;
              tabular
Default handler: &rbrace;
            </pre>
          </example>
          <noindent/>
          <para>
            The traditional typographic treatment is on the first line. On the second line the output will have some extra space between the
            <code>
              \sin
            </code>
             and the open parenthesis.
          </para>
          <para>
            Commands without
            <samp>
              l
            </samp>
             or
Default handler: &nbsp;
            <samp>
              r
            </samp>
             do give correct spacing in some circumstances, as with this large vertical line
          </para>
          <example endspaces=" ">
            <pre xml:space="preserve">
              \begin
Default handler: &lbrace;
              equation
Default handler: &rbrace;
               \int_
Default handler: &lbrace;
              x=a
Default handler: &rbrace;
              ^b x^2\,dx = \frac
Default handler: &lbrace;
              1
Default handler: &rbrace;
Default handler: &lbrace;
              3
Default handler: &rbrace;
               x^3 \Big|_
Default handler: &lbrace;
              x=a
Default handler: &rbrace;
              ^b \end
Default handler: &lbrace;
              equation
Default handler: &rbrace;
            </pre>
          </example>
          <cindex index="cp" spaces=" ">
            <indexterm index="cp" number="701">
              <r>
                package
              </r>
              ,
              <code>
                amsmath
              </code>
            </indexterm>
          </cindex>
          <cindex index="cp" spaces=" ">
            <indexterm index="cp" number="702">
              <code>
                amsmath
              </code>
              <r>
                package
              </r>
            </indexterm>
          </cindex>
          <noindent/>
          <para>
            (many authors would replace
            <code>
              \frac
            </code>
             with the
            <code>
              \tfrac
            </code>
             command from the
            <code>
              amsmath
            </code>
             package), and as with this larger slash.
          </para>
          <example endspaces=" ">
            <pre xml:space="preserve">
              \begin
Default handler: &lbrace;
              equation
Default handler: &rbrace;
               \lim_
Default handler: &lbrace;
              n\to\infty
Default handler: &rbrace;
              \pi(n) \big/ (n/\log n) = 1 \end
Default handler: &lbrace;
              equation
Default handler: &rbrace;
            </pre>
          </example>
          <para>
            Unlike the
            <code>
              \left...\right
            </code>
             pair (
            <pxref label="_005cleft-_0026-_005cright">
              <xrefnodename>
                \left
                &
                 \right
              </xrefnodename>
            </pxref>
            ), the commands here with
            <samp>
              l
            </samp>
             or
Default handler: &nbsp;
            <samp>
              r
            </samp>
             do not make a group. Strictly speaking they need not be matched so you can write something like this.
          </para>
          <example endspaces=" ">
            <pre xml:space="preserve">
              \begin
Default handler: &lbrace;
              equation
Default handler: &rbrace;
               \Biggl[ \pi/6 ] \end
Default handler: &lbrace;
              equation
Default handler: &rbrace;
            </pre>
          </example>
          <para>
            The commands with
            <samp>
              m
            </samp>
             are for relations, which are in the middle of formulas, as here.
          </para>
          <example endspaces=" ">
            <pre xml:space="preserve">
              \begin
Default handler: &lbrace;
              equation
Default handler: &rbrace;
               \biggl\
Default handler: &lbrace;
               a\in B \biggm| a=\sum_
Default handler: &lbrace;
              0\leq i
              <
              n
Default handler: &rbrace;
              3i^2+4 \biggr\
Default handler: &rbrace;
               \end
Default handler: &lbrace;
              equation
Default handler: &rbrace;
            </pre>
          </example>
Default handler: <!-- c xx Add discussion \bigg\mid not being good -->
Default handler: <!-- c and \bigg| being right; maybe mention of \middle and braket package? -->
        </subsubsection>
      </subsection>
      <node name="Dots" spaces=" ">
        <nodename>
          Dots
        </nodename>
        <nodenext automatic="on">
          Greek letters
        </nodenext>
        <nodeprev automatic="on">
          Delimiters
        </nodeprev>
        <nodeup automatic="on">
          Math symbols
        </nodeup>
      </node>
      <subsection spaces=" ">
        <sectiontitle>
          Dots, horizontal or vertical
        </sectiontitle>
        <cindex index="cp" spaces=" ">
          <indexterm index="cp" number="703">
            ellipses
          </indexterm>
        </cindex>
        <cindex index="cp" spaces=" ">
          <indexterm index="cp" number="704">
            dots
          </indexterm>
        </cindex>
        <para>
          Ellipses are the three dots (usually three) indicating that a pattern continues.
        </para>
        <example endspaces=" ">
          <pre xml:space="preserve">
            \begin
Default handler: &lbrace;
            array
Default handler: &rbrace;
Default handler: &lbrace;
            cccc
Default handler: &rbrace;
             a_
Default handler: &lbrace;
            0,0
Default handler: &rbrace;
            &
            a_
Default handler: &lbrace;
            0,1
Default handler: &rbrace;
            &
            a_
Default handler: &lbrace;
            0,2
Default handler: &rbrace;
            &
            \ldots \\ a_
Default handler: &lbrace;
            1,0
Default handler: &rbrace;
            &
            \ddots \\ \vdots \end
Default handler: &lbrace;
            array
Default handler: &rbrace;
          </pre>
        </example>
        <paraDefault handler: &latex;
>
           provides these.
        </para>
        <ftable commandarg="code" spaces=" " endspaces=" ">
          <beforefirstitem>
            <anchor name="ellipses-cdots">
              ellipses cdots
            </anchor>
          </beforefirstitem>
          <tableentry>
            <tableterm>
              <item spaces=" ">
                <itemformat command="code">
                  <indexterm index="fn" number="853" mergedindex="cp">
                    \cdots
                  </indexterm>
                  \cdots
                </itemformat>
              </item>
            </tableterm>
            <tableitem>
              <para>
                Horizontal ellipsis with the dots raised to the center of the line, as in
                <u>
                  22EF
                </u>
                . Used as:
                <code>
                  \( a_0\cdot a_1\cdots a_
Default handler: &lbrace;
                  n-1
Default handler: &rbrace;
                   \)
                </code>
                .
              </para>
              <anchor name="ellipses-ddots">
                ellipses ddots
              </anchor>
            </tableitem>
          </tableentry>
          <tableentry>
            <tableterm>
              <item spaces=" ">
                <itemformat command="code">
                  <indexterm index="fn" number="854" mergedindex="cp">
                    \ddots
                  </indexterm>
                  \ddots
                </itemformat>
              </item>
            </tableterm>
            <tableitem>
              <para>
                Diagonal ellipsis,
                <u>
                  22F1
                </u>
                . See the above array example for a usage.
              </para>
              <anchor name="ellipses-ldots">
                ellipses ldots
              </anchor>
            </tableitem>
          </tableentry>
          <tableentry>
            <tableterm>
              <item spaces=" ">
                <itemformat command="code">
                  <indexterm index="fn" number="855" mergedindex="cp">
                    \ldots
                  </indexterm>
                  \ldots
                </itemformat>
              </item>
              <itemx spaces=" ">
                <itemformat command="code">
                  <indexterm index="fn" number="856" mergedindex="cp">
                    \mathellipsis
                  </indexterm>
                  \mathellipsis
                </itemformat>
              </itemx>
              <itemx spaces=" ">
                <itemformat command="code">
                  <indexterm index="fn" number="857" mergedindex="cp">
                    \dots
                  </indexterm>
                  \dots
                </itemformat>
              </itemx>
            </tableterm>
            <tableitem>
              <para>
                Ellipsis on the baseline,
                <u>
                  2026
                </u>
                . Used as:
                <code>
                  \( x_0,\ldots x_
Default handler: &lbrace;
                  n-1
Default handler: &rbrace;
                   \)
                </code>
                . Another example is the above array example. Synonyms are
                <code>
                  \mathellipsis
                </code>
                 and
                <code>
                  \dots
                </code>
                . A synonym from the
                <code>
                  amsmath
                </code>
                 package is
                <code>
                  \hdots
                </code>
                .
              </para>
              <para>
                You can also use this command outside of mathematical text, as in
                <code>
                  The gears, brakes, \ldots
Default handler: &lbrace;
Default handler: &rbrace;
                   are all broken
                </code>
                .
              </para>
              <anchor name="ellipses-vdots">
                ellipses vdots
              </anchor>
            </tableitem>
          </tableentry>
          <tableentry>
            <tableterm>
              <item spaces=" ">
                <itemformat command="code">
                  <indexterm index="fn" number="858" mergedindex="cp">
                    \vdots
                  </indexterm>
                  \vdots
                </itemformat>
              </item>
            </tableterm>
            <tableitem>
              <para>
                Vertical ellipsis,
                <u>
                  22EE
                </u>
                . See the above array example for a usage.
              </para>
            </tableitem>
          </tableentry>
        </ftable>
        <cindex index="cp" spaces=" ">
          <indexterm index="cp" number="705">
            <r>
              package
            </r>
            ,
            <code>
              amsmath
            </code>
          </indexterm>
        </cindex>
        <cindex index="cp" spaces=" ">
          <indexterm index="cp" number="706">
            <code>
              amsmath
            </code>
            <r>
              package
            </r>
          </indexterm>
        </cindex>
        <para>
          The
          <code>
            amsmath
          </code>
           package has the command
          <code>
            \dots
          </code>
           to semantically mark up ellipses. This example produces two different-looking outputs for the first two uses of the
          <code>
            \dots
          </code>
           command.
        </para>
        <example endspaces=" ">
          <pre xml:space="preserve">
            \usepackage
Default handler: &lbrace;
            amsmath
Default handler: &rbrace;
             % in preamble ... Suppose that \( p_0, p_1, \dots, p_
Default handler: &lbrace;
            n-1
Default handler: &rbrace;
             \) lists all of the primes. Observe that \( p_0\cdot p_1 \dots \cdot p_
Default handler: &lbrace;
            n-1
Default handler: &rbrace;
             +1 \) is not a multiple of any \( p_i \). Conclusion: there are infinitely many primes \( p_0, p_1, \dotsc \).
          </pre>
        </example>
        <findex index="fn" spaces=" ">
          <indexterm index="fn" number="859" mergedindex="cp">
            \dotsc
          </indexterm>
        </findex>
        <findex index="fn" spaces=" ">
          <indexterm index="fn" number="860" mergedindex="cp">
            \dotsb
          </indexterm>
        </findex>
        <findex index="fn" spaces=" ">
          <indexterm index="fn" number="861" mergedindex="cp">
            \dotsi
          </indexterm>
        </findex>
        <findex index="fn" spaces=" ">
          <indexterm index="fn" number="862" mergedindex="cp">
            \dots
          </indexterm>
        </findex>
        <noindent/>
        <para>
          In the first line
Default handler: &latex;
           looks to the comma following
          <code>
            \dots
          </code>
           to determine that it should output an ellipsis on the baseline. The second line has a
          <code>
            \cdot
          </code>
           following
          <code>
            \dots
          </code>
           so
Default handler: &latex;
           outputs an ellipsis that is on the math axis, vertically centered. However, the third usage has no follow-on character so you have to tell
Default handler: &latex;
           what to do. You can use one of the commands:
          <code>
            \dotsc
          </code>
           if you need the ellipsis appropriate for a comma following,
          <code>
            \dotsb
          </code>
           if you need the ellipses that fits when the dots are followed by a binary operator or relation symbol,
          <code>
            \dotsi
          </code>
           for dots with integrals, or
          <code>
            \dotso
          </code>
           for others.
        </para>
Default handler: <!-- c https://github.com/latex3/latex2e/issues/976 -->
        <cindex index="cp" spaces=" ">
          <indexterm index="cp" number="707">
            <r>
              package
            </r>
            ,
            <code>
              unicode-math
            </code>
          </indexterm>
        </cindex>
        <cindex index="cp" spaces=" ">
          <indexterm index="cp" number="708">
            <code>
              unicode-math
            </code>
            <r>
              package
            </r>
          </indexterm>
        </cindex>
        <para>
          The
          <code>
            \dots
          </code>
           command from
          <code>
            amsmath
          </code>
           differs from the
Default handler: &latex;
           kernel
Default handler: &textrsquo;
          s
          <code>
            \dots
          </code>
           command in another way: it outputs a thin space after the ellipsis. Furthermore, the
          <code>
            unicode-math
          </code>
           package automatically loads
          <code>
            amsmath
          </code>
          , so
          <code>
            amsmath
          </code>
Default handler: &textrsquo;
          s
          <code>
            \dots
          </code>
           may be active even when you did not explicitly load it, thus changing the output from
          <code>
            \dots
          </code>
           in both text and math mode.
        </para>
        <cindex index="cp" spaces=" ">
          <indexterm index="cp" number="709">
            ellipsis, in Unicode (U+2026)
          </indexterm>
        </cindex>
        <cindex index="cp" spaces=" ">
          <indexterm index="cp" number="710">
            ellipsis, traditional (three periods)
          </indexterm>
        </cindex>
        <para>
          Yet more about the ellipsis commands: when running under Unicode engines (
          <code>
            lualatex
          </code>
          ,
          <code>
            xelatex
          </code>
          ),
Default handler: &latex;
           will use the Unicode ellipsis character (U+2026) in the font if it
Default handler: &textrsquo;
          s available; under traditional
Default handler: &tex;
           engines (
          <code>
            pdflatex
          </code>
          ,
          <code>
            latex
          </code>
          ), it will typeset three spaced periods. Generally, the Unicode single-character ellipsis has almost no space between the three periods, while the spacing of the non-Unicode ellipsis is looser, more in accordance with traditional typography.
        </para>
      </subsection>
      <node name="Greek-letters" spaces=" ">
        <nodename>
          Greek letters
        </nodename>
        <nodeprev automatic="on">
          Dots
        </nodeprev>
        <nodeup automatic="on">
          Math symbols
        </nodeup>
      </node>
      <subsection spaces=" ">
        <sectiontitle>
          Greek letters
        </sectiontitle>
        <cindex index="cp" spaces=" ">
          <indexterm index="cp" number="711">
            Greek letters
          </indexterm>
        </cindex>
        <para>
          The upper case versions of these Greek letters are only shown when they differ from Roman upper case letters.
        </para>
        <multitable spaces=" " endspaces=" ">
          <columnfractions spaces=" " line=".10 .30 .15 .45">
            <columnfraction value=".10"/>
            <columnfraction value=".30"/>
            <columnfraction value=".15"/>
            <columnfraction value=".45"/>
          </columnfractions>
          <thead>
            <row>
              <entry command="headitem">
                <para>
                  Symbol
                </para>
              </entry>
              <entry command="tab">
                <para>
                  Command
                </para>
              </entry>
              <entry command="tab">
                <para>
                  Name
                </para>
              </entry>
              <entry command="tab"/>
            </row>
          </thead>
          <tbody>
            <row>
              <entry command="item">
                <para>
                  <u>
                    03B1
                  </u>
                </para>
              </entry>
              <entry command="tab">
                <para>
                  <code>
                    \alpha
                  </code>
                </para>
              </entry>
              <entry command="tab">
                <para>
                  Alpha
                </para>
              </entry>
            </row>
            <row>
              <entry command="item">
                <para>
                  <u>
                    03B2
                  </u>
                </para>
              </entry>
              <entry command="tab">
                <para>
                  <code>
                    \beta
                  </code>
                </para>
              </entry>
              <entry command="tab">
                <para>
                  Beta
                </para>
              </entry>
            </row>
            <row>
              <entry command="item">
                <para>
                  <u>
                    03B3
                  </u>
                  ,
                  <u>
                    0393
                  </u>
                </para>
              </entry>
              <entry command="tab">
                <para>
                  <code>
                    \gamma
                  </code>
                  ,
                  <code>
                    \Gamma
                  </code>
                </para>
              </entry>
              <entry command="tab">
                <para>
                  Gamma
                </para>
              </entry>
            </row>
            <row>
              <entry command="item">
                <para>
                  <u>
                    03B4
                  </u>
                  ,
                  <u>
                    0394
                  </u>
                </para>
              </entry>
              <entry command="tab">
                <para>
                  <code>
                    \delta
                  </code>
                  ,
                  <code>
                    \Delta
                  </code>
                </para>
              </entry>
              <entry command="tab">
                <para>
                  Delta
                </para>
              </entry>
            </row>
            <row>
              <entry command="item">
                <para>
                  <u>
                    03B5
                  </u>
                  ,
                  <u>
                    03F5
                  </u>
                </para>
              </entry>
              <entry command="tab">
                <para>
                  <code>
                    \varepsilon
                  </code>
                  ,
                  <code>
                    \epsilon
                  </code>
                </para>
              </entry>
              <entry command="tab">
                <para>
                  Epsilon
                </para>
              </entry>
            </row>
            <row>
              <entry command="item">
                <para>
                  <u>
                    03B6
                  </u>
                </para>
              </entry>
              <entry command="tab">
                <para>
                  <code>
                    \zeta
                  </code>
                </para>
              </entry>
              <entry command="tab">
                <para>
                  Zeta
                </para>
              </entry>
            </row>
            <row>
              <entry command="item">
                <para>
                  <u>
                    03B7
                  </u>
                </para>
              </entry>
              <entry command="tab">
                <para>
                  <code>
                    \eta
                  </code>
                </para>
              </entry>
              <entry command="tab">
                <para>
                  Eta
                </para>
              </entry>
            </row>
            <row>
              <entry command="item">
                <para>
                  <u>
                    03B8
                  </u>
                  ,
                  <u>
                    03D1
                  </u>
                </para>
              </entry>
              <entry command="tab">
                <para>
                  <code>
                    \theta
                  </code>
                  ,
                  <code>
                    \vartheta
                  </code>
                </para>
              </entry>
              <entry command="tab">
                <para>
                  Theta
                </para>
              </entry>
            </row>
            <row>
              <entry command="item">
                <para>
                  <u>
                    03B9
                  </u>
                </para>
              </entry>
              <entry command="tab">
                <para>
                  <code>
                    \iota
                  </code>
                </para>
              </entry>
              <entry command="tab">
                <para>
                  Iota
                </para>
              </entry>
            </row>
            <row>
              <entry command="item">
                <para>
                  <u>
                    03BA
                  </u>
                </para>
              </entry>
              <entry command="tab">
                <para>
                  <code>
                    \kappa
                  </code>
                </para>
              </entry>
              <entry command="tab">
                <para>
                  Kappa
                </para>
              </entry>
            </row>
            <row>
              <entry command="item">
                <para>
                  <u>
                    03BB
                  </u>
                  ,
                  <u>
                    039B
                  </u>
                </para>
              </entry>
              <entry command="tab">
                <para>
                  <code>
                    \lambda
                  </code>
                  ,
                  <code>
                    \Lambda
                  </code>
                </para>
              </entry>
              <entry command="tab">
                <para>
                  Lambda
                </para>
              </entry>
            </row>
            <row>
              <entry command="item">
                <para>
                  <u>
                    03BC
                  </u>
                </para>
              </entry>
              <entry command="tab">
                <para>
                  <code>
                    \mu
                  </code>
                </para>
              </entry>
              <entry command="tab">
                <para>
                  Mu
                </para>
              </entry>
            </row>
            <row>
              <entry command="item">
                <para>
                  <u>
                    03BD
                  </u>
                </para>
              </entry>
              <entry command="tab">
                <para>
                  <code>
                    \nu
                  </code>
                </para>
              </entry>
              <entry command="tab">
                <para>
                  Nu
                </para>
              </entry>
            </row>
            <row>
              <entry command="item">
                <para>
                  <u>
                    03BE
                  </u>
                  ,
                  <u>
                    039E
                  </u>
                </para>
              </entry>
              <entry command="tab">
                <para>
                  <code>
                    \xi
                  </code>
                  ,
                  <code>
                    \Xi
                  </code>
                </para>
              </entry>
              <entry command="tab">
                <para>
                  Xi
                </para>
              </entry>
            </row>
            <row>
              <entry command="item">
                <para>
                  <u>
                    03C0
                  </u>
                  ,
                  <u>
                    03A0
                  </u>
                </para>
              </entry>
              <entry command="tab">
                <para>
                  <code>
                    \pi
                  </code>
                  ,
                  <code>
                    \Pi
                  </code>
                </para>
              </entry>
              <entry command="tab">
                <para>
                  Pi
                </para>
              </entry>
            </row>
            <row>
              <entry command="item">
                <para>
                  <u>
                    03C1
                  </u>
                  ,
                  <u>
                    03F1
                  </u>
                </para>
              </entry>
              <entry command="tab">
                <para>
                  <code>
                    \rho
                  </code>
                  ,
                  <code>
                    \varrho
                  </code>
                </para>
              </entry>
              <entry command="tab">
                <para>
                  Rho
                </para>
              </entry>
            </row>
            <row>
              <entry command="item">
                <para>
                  <u>
                    03C3
                  </u>
                  ,
                  <u>
                    03A3
                  </u>
                </para>
              </entry>
              <entry command="tab">
                <para>
                  <code>
                    \sigma
                  </code>
                  ,
                  <code>
                    \Sigma
                  </code>
                </para>
              </entry>
              <entry command="tab">
                <para>
                  Sigma
                </para>
              </entry>
            </row>
            <row>
              <entry command="item">
                <para>
                  <u>
                    03C4
                  </u>
                </para>
              </entry>
              <entry command="tab">
                <para>
                  <code>
                    \tau
                  </code>
                </para>
              </entry>
              <entry command="tab">
                <para>
                  Tau
                </para>
              </entry>
            </row>
            <row>
              <entry command="item">
                <para>
                  <u>
                    03D5
                  </u>
                  ,
                  <u>
                    03C6
                  </u>
                  ,
                  <u>
                    03A6
                  </u>
                </para>
              </entry>
              <entry command="tab">
                <para>
                  <code>
                    \phi
                  </code>
                  ,
                  <code>
                    \varphi
                  </code>
                  ,
                  <code>
                    \Phi
                  </code>
                </para>
              </entry>
              <entry command="tab">
                <para>
                  Phi
                </para>
              </entry>
            </row>
            <row>
              <entry command="item">
                <para>
                  <u>
                    03C7
                  </u>
                </para>
              </entry>
              <entry command="tab">
                <para>
                  <code>
                    \chi
                  </code>
                </para>
              </entry>
              <entry command="tab">
                <para>
                  chi
                </para>
              </entry>
            </row>
            <row>
              <entry command="item">
                <para>
                  <u>
                    03C8
                  </u>
                  ,
                  <u>
                    03A8
                  </u>
                </para>
              </entry>
              <entry command="tab">
                <para>
                  <code>
                    \psi
                  </code>
                  ,
                  <code>
                    \Psi
                  </code>
                </para>
              </entry>
              <entry command="tab">
                <para>
                  Psi
                </para>
              </entry>
            </row>
            <row>
              <entry command="item">
                <para>
                  <u>
                    03C9
                  </u>
                  ,
                  <u>
                    03A9
                  </u>
                </para>
              </entry>
              <entry command="tab">
                <para>
                  <code>
                    \omega
                  </code>
                  ,
                  <code>
                    \Omega
                  </code>
                </para>
              </entry>
              <entry command="tab">
                <para>
                  Omega
                </para>
              </entry>
            </row>
          </tbody>
        </multitable>
        <cindex index="cp" spaces=" ">
          <indexterm index="cp" number="712">
            <r>
              package
            </r>
            ,
            <code>
              unicode-math
            </code>
          </indexterm>
        </cindex>
        <cindex index="cp" spaces=" ">
          <indexterm index="cp" number="713">
            <code>
              unicode-math
            </code>
            <r>
              package
            </r>
          </indexterm>
        </cindex>
        <para>
          For omicron, if you are using
Default handler: &latex;
Default handler: &textrsquo;
          s default Computer Modern font then enter omicron just as
          <samp>
            o
          </samp>
           or
          <samp>
            O
          </samp>
          . If you like having the name or if your font shows a difference then you can use something like
          <code>
            \newcommand\omicron
Default handler: &lbrace;
            o
Default handler: &rbrace;
          </code>
          . The package
          <code>
            unicode-math
          </code>
           has
          <code>
            \upomicron
          </code>
           for upright omicron and
          <code>
            \mitomicron
          </code>
           for math italic.
        </para>
        <para>
          While the set membership relation symbol
          <u>
            2208
          </u>
           generated by
          <code>
            \in
          </code>
           is related to epsilon, it is never used for a variable.
        </para>
      </subsection>
    </section>
    <node name="Math-functions" spaces=" ">
      <nodename>
        Math functions
      </nodename>
      <nodenext automatic="on">
        Math accents
      </nodenext>
      <nodeprev automatic="on">
        Math symbols
      </nodeprev>
      <nodeup automatic="on">
        Math formulas
      </nodeup>
    </node>
    <section spaces=" ">
      <sectiontitle>
        Math functions
      </sectiontitle>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="714">
          math functions
        </indexterm>
      </cindex>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="715">
          functions, math
        </indexterm>
      </cindex>
      <para>
        These commands produce roman function names in math mode with proper spacing.
      </para>
      <ftable commandarg="code" spaces=" " endspaces=" ">
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                <indexterm index="fn" number="863" mergedindex="cp">
                  \arccos
                </indexterm>
                \arccos
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <para>
              Inverse cosine
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                <indexterm index="fn" number="864" mergedindex="cp">
                  \arcsin
                </indexterm>
                \arcsin
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <para>
              Inverse sine
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                <indexterm index="fn" number="865" mergedindex="cp">
                  \arctan
                </indexterm>
                \arctan
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <para>
              Inverse tangent
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                <indexterm index="fn" number="866" mergedindex="cp">
                  \arg
                </indexterm>
                \arg
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <para>
              Angle between the real axis and a point in the complex plane
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                <indexterm index="fn" number="867" mergedindex="cp">
                  \bmod
                </indexterm>
                \bmod
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <para>
              Binary modulo operator, used as in
              <code>
                \( 5\bmod 3=2 \)
              </code>
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                <indexterm index="fn" number="868" mergedindex="cp">
                  \cos
                </indexterm>
                \cos
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <para>
              Cosine
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                <indexterm index="fn" number="869" mergedindex="cp">
                  \cosh
                </indexterm>
                \cosh
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <para>
              Hyperbolic cosine
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                <indexterm index="fn" number="870" mergedindex="cp">
                  \cot
                </indexterm>
                \cot
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <para>
              Cotangent
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                <indexterm index="fn" number="871" mergedindex="cp">
                  \coth
                </indexterm>
                \coth
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <para>
              Hyperbolic cotangent
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                <indexterm index="fn" number="872" mergedindex="cp">
                  \csc
                </indexterm>
                \csc
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <para>
              Cosecant
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                <indexterm index="fn" number="873" mergedindex="cp">
                  \deg
                </indexterm>
                \deg
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <para>
              Degrees
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                <indexterm index="fn" number="874" mergedindex="cp">
                  \det
                </indexterm>
                \det
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <para>
              Determinant
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                <indexterm index="fn" number="875" mergedindex="cp">
                  \dim
                </indexterm>
                \dim
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <para>
              Dimension
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                <indexterm index="fn" number="876" mergedindex="cp">
                  \exp
                </indexterm>
                \exp
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <para>
              Exponential
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                <indexterm index="fn" number="877" mergedindex="cp">
                  \gcd
                </indexterm>
                \gcd
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <para>
              Greatest common divisor
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                <indexterm index="fn" number="878" mergedindex="cp">
                  \hom
                </indexterm>
                \hom
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <para>
              Homomorphism
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                <indexterm index="fn" number="879" mergedindex="cp">
                  \inf
                </indexterm>
                \inf
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <para>
              Infimum
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                <indexterm index="fn" number="880" mergedindex="cp">
                  \ker
                </indexterm>
                \ker
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <para>
              Kernel
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                <indexterm index="fn" number="881" mergedindex="cp">
                  \lg
                </indexterm>
                \lg
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <para>
              Base 2 logarithm
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                <indexterm index="fn" number="882" mergedindex="cp">
                  \lim
                </indexterm>
                \lim
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <para>
              Limit
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                <indexterm index="fn" number="883" mergedindex="cp">
                  \liminf
                </indexterm>
                \liminf
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <para>
              Limit inferior
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                <indexterm index="fn" number="884" mergedindex="cp">
                  \limsup
                </indexterm>
                \limsup
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <para>
              Limit superior
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                <indexterm index="fn" number="885" mergedindex="cp">
                  \ln
                </indexterm>
                \ln
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <para>
              Natural logarithm
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                <indexterm index="fn" number="886" mergedindex="cp">
                  \log
                </indexterm>
                \log
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <para>
              Logarithm
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                <indexterm index="fn" number="887" mergedindex="cp">
                  \max
                </indexterm>
                \max
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <para>
              Maximum
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                <indexterm index="fn" number="888" mergedindex="cp">
                  \min
                </indexterm>
                \min
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <para>
              Minimum
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                <indexterm index="fn" number="889" mergedindex="cp">
                  \pmod
                </indexterm>
                \pmod
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <para>
              Parenthesized modulus, as used in
              <code>
                \( 5\equiv 2\pmod 3 \)
              </code>
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                <indexterm index="fn" number="890" mergedindex="cp">
                  \Pr
                </indexterm>
                \Pr
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <para>
              Probability
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                <indexterm index="fn" number="891" mergedindex="cp">
                  \sec
                </indexterm>
                \sec
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <para>
              Secant
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                <indexterm index="fn" number="892" mergedindex="cp">
                  \sin
                </indexterm>
                \sin
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <para>
              Sine
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                <indexterm index="fn" number="893" mergedindex="cp">
                  \sinh
                </indexterm>
                \sinh
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <para>
              Hyperbolic sine
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                <indexterm index="fn" number="894" mergedindex="cp">
                  \sup
                </indexterm>
                \sup
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <para>
              Supremum sup
Default handler: <!-- c don't try to use \sup with dvi/pdf output since that turned into a -->
Default handler: <!-- c Texinfo command and it's not worth hassling with different versions -->
Default handler: <!-- c when it's just three roman letters anyway. -->
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                <indexterm index="fn" number="895" mergedindex="cp">
                  \tan
                </indexterm>
                \tan
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <para>
              Tangent
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                <indexterm index="fn" number="896" mergedindex="cp">
                  \tanh
                </indexterm>
                \tanh
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <para>
              Hyperbolic tangent
            </para>
          </tableitem>
        </tableentry>
      </ftable>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="716">
          <r>
            package
          </r>
          ,
          <code>
            amsmath
          </code>
        </indexterm>
      </cindex>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="717">
          <code>
            amsmath
          </code>
          <r>
            package
          </r>
        </indexterm>
      </cindex>
      <para>
        The
        <code>
          amsmath
        </code>
         package adds improvements on some of these, and also allows you to define your own. The full documentation is on CTAN, but briefly, you can define an identity operator with
        <code>
          \DeclareMathOperator
Default handler: &lbrace;
          \identity
Default handler: &rbrace;
Default handler: &lbrace;
          id
Default handler: &rbrace;
        </code>
         that is like the ones above but prints as
        <samp>
          id
        </samp>
        . The starred form
        <code>
          \DeclareMathOperator*
Default handler: &lbrace;
          \op
Default handler: &rbrace;
Default handler: &lbrace;
          op
Default handler: &rbrace;
        </code>
         sets any superscript or subscript to be above and below, as is traditional with
        <code>
          \lim
        </code>
        ,
        <code>
          \sup
        </code>
        , or
        <code>
          \max
        </code>
        .
      </para>
    </section>
    <node name="Math-accents" spaces=" ">
      <nodename>
        Math accents
      </nodename>
      <nodenext automatic="on">
        Over- or under math
      </nodenext>
      <nodeprev automatic="on">
        Math functions
      </nodeprev>
      <nodeup automatic="on">
        Math formulas
      </nodeup>
    </node>
    <section spaces=" ">
      <sectiontitle>
        Math accents
      </sectiontitle>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="718">
          math accents
        </indexterm>
      </cindex>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="719">
          accents, mathematical
        </indexterm>
      </cindex>
      <paraDefault handler: &latex;
>
         provides a variety of commands for producing accented letters in math. These are different from accents in normal text (
        <pxref label="Accents">
          <xrefnodename>
            Accents
          </xrefnodename>
        </pxref>
        ).
      </para>
      <ftable commandarg="code" spaces=" " endspaces=" ">
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                <indexterm index="fn" number="897" mergedindex="cp">
                  \acute
                </indexterm>
                \acute
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <cindex index="cp" spaces=" ">
              <indexterm index="cp" number="720">
                acute accent, math
              </indexterm>
            </cindex>
            <para>
              Math acute accent
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                <indexterm index="fn" number="898" mergedindex="cp">
                  \bar
                </indexterm>
                \bar
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <cindex index="cp" spaces=" ">
              <indexterm index="cp" number="721">
                bar-over accent, math
              </indexterm>
            </cindex>
            <cindex index="cp" spaces=" ">
              <indexterm index="cp" number="722">
                macron accent, math
              </indexterm>
            </cindex>
            <para>
              Math bar-over accent
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                <indexterm index="fn" number="899" mergedindex="cp">
                  \breve
                </indexterm>
                \breve
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <cindex index="cp" spaces=" ">
              <indexterm index="cp" number="723">
                breve accent, math
              </indexterm>
            </cindex>
            <para>
              Math breve accent
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                <indexterm index="fn" number="900" mergedindex="cp">
                  \check
                </indexterm>
                \check
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <cindex index="cp" spaces=" ">
              <indexterm index="cp" number="724">
                check accent, math
              </indexterm>
            </cindex>
            <cindex index="cp" spaces=" ">
              <indexterm index="cp" number="725">
                h
                <accent type="acute" bracketed="off">
                  a
                </accent>
                <accent type="caron">
                  c
                </accent>
                ek accent, math
              </indexterm>
            </cindex>
            <para>
              Math h
              <accent type="acute" bracketed="off">
                a
              </accent>
              <accent type="caron">
                c
              </accent>
              ek (check) accent
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                <indexterm index="fn" number="901" mergedindex="cp">
                  \ddot
                </indexterm>
                \ddot
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <cindex index="cp" spaces=" ">
              <indexterm index="cp" number="726">
                double dot accent, math
              </indexterm>
            </cindex>
            <para>
              Math dieresis accent
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                <indexterm index="fn" number="902" mergedindex="cp">
                  \dot
                </indexterm>
                \dot
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <cindex index="cp" spaces=" ">
              <indexterm index="cp" number="727">
                overdot accent, math
              </indexterm>
            </cindex>
            <cindex index="cp" spaces=" ">
              <indexterm index="cp" number="728">
                dot over accent, math
              </indexterm>
            </cindex>
            <para>
              Math dot accent
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                <indexterm index="fn" number="903" mergedindex="cp">
                  \grave
                </indexterm>
                \grave
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <cindex index="cp" spaces=" ">
              <indexterm index="cp" number="729">
                grave accent, math
              </indexterm>
            </cindex>
            <para>
              Math grave accent
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                <indexterm index="fn" number="904" mergedindex="cp">
                  \hat
                </indexterm>
                \hat
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <cindex index="cp" spaces=" ">
              <indexterm index="cp" number="730">
                hat accent, math
              </indexterm>
            </cindex>
            <cindex index="cp" spaces=" ">
              <indexterm index="cp" number="731">
                circumflex accent, math
              </indexterm>
            </cindex>
            <para>
              Math hat (circumflex) accent
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                <indexterm index="fn" number="905" mergedindex="cp">
                  \mathring
                </indexterm>
                \mathring
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <cindex index="cp" spaces=" ">
              <indexterm index="cp" number="732">
                ring accent, math
              </indexterm>
            </cindex>
            <para>
              Math ring accent
Default handler: <!-- c don't bother implementing in texinfo -->
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                <indexterm index="fn" number="906" mergedindex="cp">
                  \tilde
                </indexterm>
                \tilde
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <cindex index="cp" spaces=" ">
              <indexterm index="cp" number="733">
                tilde accent, math
              </indexterm>
            </cindex>
            <para>
              Math tilde accent
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                <indexterm index="fn" number="907" mergedindex="cp">
                  \vec
                </indexterm>
                \vec
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <cindex index="cp" spaces=" ">
              <indexterm index="cp" number="734">
                vector symbol, math
              </indexterm>
            </cindex>
            <para>
              Math vector symbol
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                <indexterm index="fn" number="908" mergedindex="cp">
                  \widehat
                </indexterm>
                \widehat
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <cindex index="cp" spaces=" ">
              <indexterm index="cp" number="735">
                wide hat accent, math
              </indexterm>
            </cindex>
            <para>
              Math wide hat accent
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                <indexterm index="fn" number="909" mergedindex="cp">
                  \widetilde
                </indexterm>
                \widetilde
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <cindex index="cp" spaces=" ">
              <indexterm index="cp" number="736">
                wide tilde accent, math
              </indexterm>
            </cindex>
            <para>
              Math wide tilde accent
            </para>
          </tableitem>
        </tableentry>
      </ftable>
      <para>
        When you are putting an accent on an i or a j, the tradition is to use one without a dot,
        <code>
          \imath
        </code>
         or
        <code>
          jmath
        </code>
         (
        <pxref label="Math-symbols">
          <xrefnodename>
            Math symbols
          </xrefnodename>
        </pxref>
        ).
      </para>
    </section>
    <node name="Over_002d-or-under-math" spaces=" ">
      <nodename>
        Over- or under math
      </nodename>
      <nodenext automatic="on">
        Spacing in math mode
      </nodenext>
      <nodeprev automatic="on">
        Math accents
      </nodeprev>
      <nodeup automatic="on">
        Math formulas
      </nodeup>
    </node>
    <section spaces=" ">
      <sectiontitle>
        Over- or under math
      </sectiontitle>
      <anchor name="Over_002d-and-Underlining">
        Over- and Underlining
      </anchor>
Default handler: <!-- c original node name -->
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="737">
          overlining
        </indexterm>
      </cindex>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="738">
          underlining
        </indexterm>
      </cindex>
      <paraDefault handler: &latex;
>
         provides commands for putting lines, braces, and arrows over or under math material.
      </para>
      <ftable commandarg="code" spaces=" " endspaces=" ">
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                <indexterm index="fn" number="910" mergedindex="cp">
                  \underline
Default handler: &lbrace;
                  <var>
                    math
                  </var>
Default handler: &rbrace;
                </indexterm>
                \underline
Default handler: &lbrace;
                <var>
                  math
                </var>
Default handler: &rbrace;
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <para>
              Underline
              <var>
                math
              </var>
              . For example:
              <code>
                \underline
Default handler: &lbrace;
                x+y
Default handler: &rbrace;
              </code>
              . The line is always completely below the text, taking account of descenders, so in
              <code>
                \(\underline
Default handler: &lbrace;
                y
Default handler: &rbrace;
                \)
              </code>
               the line is lower than in
              <code>
                \(\underline
Default handler: &lbrace;
                x
Default handler: &rbrace;
                \)
              </code>
              . As of approximately 2019, this command and others in this section are robust; before that, they were fragile (
              <pxref label="_005cprotect">
                <xrefnodename>
                  \protect
                </xrefnodename>
              </pxref>
              ).
            </para>
            <cindex index="cp" spaces=" ">
              <indexterm index="cp" number="739">
                <r>
                  package
                </r>
                ,
                <code>
                  ulem
                </code>
              </indexterm>
            </cindex>
            <cindex index="cp" spaces=" ">
              <indexterm index="cp" number="740">
                <code>
                  ulem
                </code>
                <r>
                  package
                </r>
              </indexterm>
            </cindex>
            <para>
              The package
              <code>
                ulem
              </code>
               (
              <url>
                <urefurl>
                  https://ctan.org/pkg/uelem
                </urefurl>
              </url>
              ) does text mode underlining and allows line breaking as well as a number of other features. See also
Default handler: &nbsp;
              <ref label="_005chrulefill-_0026-_005cdotfill">
                <xrefnodename>
                  \hrulefill
                  &
                   \dotfill
                </xrefnodename>
              </ref>
               for producing a line for such things as a signature or placeholder.
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                <indexterm index="fn" number="911" mergedindex="cp">
                  \overline
Default handler: &lbrace;
                  <var>
                    math
                  </var>
Default handler: &rbrace;
                </indexterm>
                \overline
Default handler: &lbrace;
                <var>
                  math
                </var>
Default handler: &rbrace;
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <para>
              Put a horizontal line over
              <var>
                math
              </var>
              . For example:
              <code>
                \overline
Default handler: &lbrace;
                x+y
Default handler: &rbrace;
              </code>
              . This differs from the accent command
              <code>
                \bar
              </code>
               (
              <pxref label="Math-accents">
                <xrefnodename>
                  Math accents
                </xrefnodename>
              </pxref>
              ).
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                <indexterm index="fn" number="912" mergedindex="cp">
                  \underbrace
Default handler: &lbrace;
                  <var>
                    math
                  </var>
Default handler: &rbrace;
                </indexterm>
                \underbrace
Default handler: &lbrace;
                <var>
                  math
                </var>
Default handler: &rbrace;
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <para>
              Put a brace under
              <var>
                math
              </var>
              . For example:
              <code>
                (1-\underbrace
Default handler: &lbrace;
                1/2)+(1/2
Default handler: &rbrace;
                -1/3)
              </code>
              .
            </para>
            <para>
              You can attach text to the brace as a subscript (
              <code>
                _
              </code>
              ) or superscript (
              <code>
                ^
              </code>
              ) as here:
            </para>
            <example endspaces=" ">
              <pre xml:space="preserve">
                \begin
Default handler: &lbrace;
                displaymath
Default handler: &rbrace;
                 1+1/2+\underbrace
Default handler: &lbrace;
                1/3+1/4
Default handler: &rbrace;
                _
Default handler: &lbrace;
                >
                1/2
Default handler: &rbrace;
                + \underbrace
Default handler: &lbrace;
                1/5+1/6+1/7+1/8
Default handler: &rbrace;
                _
Default handler: &lbrace;
                >
                1/2
Default handler: &rbrace;
                +\cdots \end
Default handler: &lbrace;
                displaymath
Default handler: &rbrace;
              </pre>
            </example>
            <para>
              The superscript appears on top of the expression, and so can look unconnected to the underbrace.
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                <indexterm index="fn" number="913" mergedindex="cp">
                  \overbrace
Default handler: &lbrace;
                  <var>
                    math
                  </var>
Default handler: &rbrace;
                </indexterm>
                \overbrace
Default handler: &lbrace;
                <var>
                  math
                </var>
Default handler: &rbrace;
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <para>
              Put a brace over
              <var>
                math
              </var>
              . For example:
Default handler: &linebreak;
              <code>
                \overbrace
Default handler: &lbrace;
                x+x+\cdots+x
Default handler: &rbrace;
                ^
Default handler: &lbrace;
                \mbox
Default handler: &lbrace;
                \(k\) times
Default handler: &rbrace;
Default handler: &rbrace;
              </code>
              .
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                <indexterm index="fn" number="914" mergedindex="cp">
                  \overrightarrow
Default handler: &lbrace;
                  <var>
                    math
                  </var>
Default handler: &rbrace;
                </indexterm>
                \overrightarrow
Default handler: &lbrace;
                <var>
                  math
                </var>
Default handler: &rbrace;
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <para>
              Put a right arrow over
              <var>
                math
              </var>
              . For example:
              <code>
                \overrightarrow
Default handler: &lbrace;
                x+y
Default handler: &rbrace;
              </code>
              .
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                <indexterm index="fn" number="915" mergedindex="cp">
                  \overleftarrow
Default handler: &lbrace;
                  <var>
                    math
                  </var>
Default handler: &rbrace;
                </indexterm>
                \overleftarrow
Default handler: &lbrace;
                <var>
                  math
                </var>
Default handler: &rbrace;
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <para>
              Put a left arrow over
              <var>
                math
              </var>
              . For example:
              <code>
                \overleftarrow
Default handler: &lbrace;
                a+b
Default handler: &rbrace;
              </code>
              .
            </para>
          </tableitem>
        </tableentry>
      </ftable>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="741">
          <r>
            package
          </r>
          ,
          <code>
            mathtools
          </code>
        </indexterm>
      </cindex>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="742">
          <code>
            mathtools
          </code>
          <r>
            package
          </r>
        </indexterm>
      </cindex>
      <para>
        The package
        <code>
          mathtools
        </code>
         (
        <url>
          <urefurl>
            https://ctan.org/pkg/mathtools
          </urefurl>
        </url>
        ) adds an over- and underbracket, as well as some improvements on the braces.
      </para>
    </section>
    <node name="Spacing-in-math-mode" spaces=" ">
      <nodename>
        Spacing in math mode
      </nodename>
      <nodenext automatic="on">
        Math styles
      </nodenext>
      <nodeprev automatic="on">
        Over- or under math
      </nodeprev>
      <nodeup automatic="on">
        Math formulas
      </nodeup>
    </node>
    <section spaces=" ">
      <sectiontitle>
        Spacing in math mode
      </sectiontitle>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="743">
          spacing within math mode
        </indexterm>
      </cindex>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="744">
          math mode, spacing
        </indexterm>
      </cindex>
      <para>
        When typesetting mathematics,
Default handler: &latex;
         puts in spacing according to the normal rules for mathematics texts. If you enter
        <code>
          y=m x
        </code>
         then
Default handler: &latex;
         ignores the space and in the output the m is next to the x, as
        <math>
          y=mx
        </math>
        .
      </para>
      <para>
        But
Default handler: &latex;
Default handler: &textrsquo;
        s rules occasionally need tweaking. For example, in an integral the tradition is to put a small extra space between the
        <code>
          f(x)
        </code>
         and the
        <code>
          dx
        </code>
        , here done with the
        <code>
          \,
        </code>
         command:
      </para>
      <example endspaces=" ">
        <pre xml:space="preserve">
          \int_0^1 f(x)\,dx
        </pre>
      </example>
      <paraDefault handler: &latex;
>
         provides the commands that follow for use in math mode. Many of these spacing definitions are expressed in terms of the math unit
        <dfn>
          mu
        </dfn>
        . It is defined as 1/18
        <dmn>
          em
        </dmn>
        , where the em is taken from the current math symbols family (
        <pxref label="Units-of-length">
          <xrefnodename>
            Units of length
          </xrefnodename>
        </pxref>
        ). Thus, a
        <code>
          \thickspace
        </code>
         is something like 5/18 times the width of a
Default handler: &nbsp;
        <samp>
          M
        </samp>
        .
      </para>
      <table commandarg="code" spaces=" " endspaces=" ">
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                \;
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <findex index="fn" spaces=" ">
              <indexterm index="fn" number="916" mergedindex="cp">
                \;
              </indexterm>
            </findex>
            <findex index="fn" spaces=" ">
              <indexterm index="fn" number="917" mergedindex="cp">
                \thickspace
              </indexterm>
            </findex>
            <anchor name="spacing-in-math-mode-thickspace">
              spacing in math mode thickspace
            </anchor>
            <cindex index="cp" spaces=" ">
              <indexterm index="cp" number="745">
                <r>
                  package
                </r>
                ,
                <code>
                  amsmath
                </code>
              </indexterm>
            </cindex>
            <cindex index="cp" spaces=" ">
              <indexterm index="cp" number="746">
                <code>
                  amsmath
                </code>
                <r>
                  package
                </r>
              </indexterm>
            </cindex>
            <para>
              Synonym:
              <code>
                \thickspace
              </code>
              . Normally
              <code>
                5.0mu plus 5.0mu
              </code>
              . With the
              <code>
                amsmath
              </code>
               package, or as of the 2020-10-01
Default handler: &latex;
               release, can be used in text mode as well as math mode; otherwise, in math mode only.
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                \negthickspace
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <findex index="fn" spaces=" ">
              <indexterm index="fn" number="918" mergedindex="cp">
                \negthickspace
              </indexterm>
            </findex>
            <para>
              Normally
              <code>
                -5.0mu plus 2.0mu minus 4.0mu
              </code>
              . With the
              <code>
                amsmath
              </code>
               package, or as of the 2020-10-01
Default handler: &latex;
               release, can be used in text mode as well as math mode; otherwise, in math mode only.
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                \:
              </itemformat>
            </item>
            <itemx spaces=" ">
              <itemformat command="code">
                \
                >
              </itemformat>
            </itemx>
          </tableterm>
          <tableitem>
            <findex index="fn" spaces=" ">
              <indexterm index="fn" number="919" mergedindex="cp">
                \:
              </indexterm>
            </findex>
            <findex index="fn" spaces=" ">
              <indexterm index="fn" number="920" mergedindex="cp">
                \
                >
              </indexterm>
            </findex>
            <findex index="fn" spaces=" ">
              <indexterm index="fn" number="921" mergedindex="cp">
                \medspace
              </indexterm>
            </findex>
            <anchor name="spacing-in-math-mode-medspace">
              spacing in math mode medspace
            </anchor>
            <para>
              Synonym:
              <code>
                \medspace
              </code>
              . Normally
              <code>
                4.0mu plus 2.0mu minus 4.0mu
              </code>
              . With the
              <code>
                amsmath
              </code>
               package, or as of the 2020-10-01
Default handler: &latex;
               release, can be used in text mode as well as math mode; before that, in math mode only.
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                \negmedspace
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <findex index="fn" spaces=" ">
              <indexterm index="fn" number="922" mergedindex="cp">
                \negmedspace
              </indexterm>
            </findex>
            <para>
              Normally
              <code>
                -4.0mu plus 2.0mu minus 4.0mu
              </code>
              . With the
              <code>
                amsmath
              </code>
               package, or as of the 2020-10-01
Default handler: &latex;
               release, can be used in text mode as well as math mode; before that, in math mode only.
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                \,
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <findex index="fn" spaces=" ">
              <indexterm index="fn" number="923" mergedindex="cp">
                \,
              </indexterm>
            </findex>
            <findex index="fn" spaces=" ">
              <indexterm index="fn" number="924" mergedindex="cp">
                \thinspace
              </indexterm>
            </findex>
            <cindex index="cp" spaces=" ">
              <indexterm index="cp" number="747">
                thin space
              </indexterm>
            </cindex>
            <anchor name="Spacing-in-math-mode_002f_005cthinspace">
              Spacing in math mode/\thinspace
            </anchor>
            <anchor name="spacing-in-math-mode-thinspace">
              spacing in math mode thinspace
            </anchor>
            <para>
              Synonym:
              <code>
                \thinspace
              </code>
              . Normally
              <code>
                3mu
              </code>
              , which is 1/6
              <dmn>
                em
              </dmn>
              . Can be used in both math mode and text mode (
              <pxref label="_005cthinspace-_0026-_005cnegthinspace">
                <xrefnodename>
                  \thinspace
                  &
                   \negthinspace
                </xrefnodename>
              </pxref>
              ).
            </para>
            <para>
              This space is widely used, for instance between the function and the infinitesimal in an integral
              <code>
                \int f(x)\,dx
              </code>
               and, if an author does this, before punctuation in a displayed equation.
            </para>
            <example endspaces=" ">
              <pre xml:space="preserve">
                The antiderivative is \begin
Default handler: &lbrace;
                equation
Default handler: &rbrace;
                 3x^
Default handler: &lbrace;
                -1/2
Default handler: &rbrace;
                +3^
Default handler: &lbrace;
                1/2
Default handler: &rbrace;
                \,. \end
Default handler: &lbrace;
                equation
Default handler: &rbrace;
              </pre>
            </example>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                \!
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <findex index="fn" spaces=" ">
              <indexterm index="fn" number="925" mergedindex="cp">
                \!
              </indexterm>
            </findex>
            <findex index="fn" spaces=" ">
              <indexterm index="fn" number="926" mergedindex="cp">
                \negthinspace
              </indexterm>
            </findex>
            <cindex index="cp" spaces=" ">
              <indexterm index="cp" number="748">
                thin space, negative
              </indexterm>
            </cindex>
            <anchor name="spacing-in-math-mode-negthinspace">
              spacing in math mode negthinspace
            </anchor>
            <para>
              Synonym:
              <code>
                \negthinspace
              </code>
              . A negative thin space. Normally
              <code>
                -3mu
              </code>
              . With the
              <code>
                amsmath
              </code>
               package, or as of the 2020-10-01
Default handler: &latex;
               release, can be used in text mode as well as math mode; otherwise, the
              <code>
                \!
              </code>
               command is math mode only but the
              <code>
                \negthinspace
              </code>
               command has always also worked in text mode (
              <pxref label="_005cthinspace-_0026-_005cnegthinspace">
                <xrefnodename>
                  \thinspace
                  &
                   \negthinspace
                </xrefnodename>
              </pxref>
              ).
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                \quad
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <cindex index="cp" spaces=" ">
              <indexterm index="cp" number="749">
                quad
              </indexterm>
            </cindex>
            <findex index="fn" spaces=" ">
              <indexterm index="fn" number="927" mergedindex="cp">
                \quad
              </indexterm>
            </findex>
            <anchor name="spacing-in-math-mode-quad">
              spacing in math mode quad
            </anchor>
            <para>
              This is 18
              <dmn>
                mu
              </dmn>
              , that is, 1
              <dmn>
                em
              </dmn>
              . This is often used for space surrounding equations or expressions, for instance for the space between two equations inside a
              <code>
                displaymath
              </code>
               environment. It is available in both text and math mode.
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                \qquad
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <findex index="fn" spaces=" ">
              <indexterm index="fn" number="928" mergedindex="cp">
                \qquad
              </indexterm>
            </findex>
            <anchor name="spacing-in-math-mode-qquad">
              spacing in math mode qquad
            </anchor>
            <para>
              A length of 2 quads, that is, 36
              <dmn>
                mu
              </dmn>
               = 2
              <dmn>
                em
              </dmn>
              . It is available in both text and math mode.
            </para>
          </tableitem>
        </tableentry>
      </table>
      <menu endspaces=" ">
        <menuentry>
          <menuleadingtext>
            *
          </menuleadingtext>
          <menunode>
            \smash
          </menunode>
          <menuseparator>
            ::
          </menuseparator>
          <menudescription>
            <pre xml:space="preserve">
              Eliminate height or depth of a subformula.
            </pre>
          </menudescription>
        </menuentry>
        <menuentry>
          <menuleadingtext>
            *
          </menuleadingtext>
          <menunode>
            \phantom
            &
             \vphantom
            &
             \hphantom
          </menunode>
          <menuseparator>
            ::
          </menuseparator>
          <menudescription>
            <pre xml:space="preserve">
              Make empty box same size as argument.
            </pre>
          </menudescription>
        </menuentry>
        <menuentry>
          <menuleadingtext>
            *
          </menuleadingtext>
          <menunode>
            \mathstrut
          </menunode>
          <menuseparator>
            ::
          </menuseparator>
          <menudescription>
            <pre xml:space="preserve">
              Add some vertical space to a formula.
            </pre>
          </menudescription>
        </menuentry>
      </menu>
      <node name="_005csmash" spaces=" ">
        <nodename>
          \smash
        </nodename>
        <nodenext automatic="on">
          \phantom
          &
           \vphantom
          &
           \hphantom
        </nodenext>
        <nodeup automatic="on">
          Spacing in math mode
        </nodeup>
      </node>
      <subsection spaces=" ">
        <sectiontitle>
          <code>
            \smash
          </code>
        </sectiontitle>
        <cindex index="cp" spaces=" ">
          <indexterm index="cp" number="750">
            vertical spacing, math mode
          </indexterm>
        </cindex>
        <cindex index="cp" spaces=" ">
          <indexterm index="cp" number="751">
            math mode, vertical space
          </indexterm>
        </cindex>
        <para>
          Synopsis:
        </para>
        <example endspaces=" ">
          <pre xml:space="preserve">
            \smash
Default handler: &lbrace;
            <var>
              subformula
            </var>
Default handler: &rbrace;
          </pre>
        </example>
        <para>
          Typeset
          <var>
            subformula
          </var>
           as if its height and depth were zero.
        </para>
        <para>
          In this example the exponential is so tall that without the
          <code>
            \smash
          </code>
           command
Default handler: &latex;
           would separate its line from the line above it, and the uneven line spacing might be unsightly.
        </para>
        <example endspaces=" ">
          <pre xml:space="preserve">
            To compute the tetration $\smash
Default handler: &lbrace;
            2^
Default handler: &lbrace;
            2^
Default handler: &lbrace;
            2^2
Default handler: &rbrace;
Default handler: &rbrace;
Default handler: &rbrace;
            $, evaluate from the top down, as $2^
Default handler: &lbrace;
            2^4
Default handler: &rbrace;
            =2^
Default handler: &lbrace;
            16
Default handler: &rbrace;
            =65536$.
          </pre>
        </example>
        <para>
          (Because of the
          <code>
            \smash
          </code>
           the printed expression could run into the line above so you may want to wait until the final version of the document to make such adjustments.)
        </para>
        <para>
          This pictures the effect of
          <code>
            \smash
          </code>
           by using
          <code>
            \fbox
          </code>
           to surround the box that
Default handler: &latex;
           will put on the line. The
          <code>
            \blackbar
          </code>
           command makes a bar extending from 10
Default handler: &nbsp;
          points below the baseline to 20
Default handler: &nbsp;
          points above.
        </para>
        <example endspaces=" ">
          <pre xml:space="preserve">
            \newcommand
Default handler: &lbrace;
            \blackbar
Default handler: &rbrace;
Default handler: &lbrace;
            \rule[-10pt]
Default handler: &lbrace;
            5pt
Default handler: &rbrace;
Default handler: &lbrace;
            30pt
Default handler: &rbrace;
Default handler: &rbrace;
             \fbox
Default handler: &lbrace;
            \blackbar
Default handler: &rbrace;
             \fbox
Default handler: &lbrace;
            \smash
Default handler: &lbrace;
            \blackbar
Default handler: &rbrace;
Default handler: &rbrace;
          </pre>
        </example>
        <para>
          The first box that
Default handler: &latex;
           places is 20
Default handler: &nbsp;
          points high and 10
Default handler: &nbsp;
          points deep. But the second box is treated by
Default handler: &latex;
           as having zero height and zero depth, despite that the ink printed on the page still extends well above and below the line.
        </para>
        <para>
          The
          <code>
            \smash
          </code>
           command appears often in mathematics to adjust the size of an element that surrounds a subformula. Here the first radical extends below the baseline while the second lies just on the baseline.
        </para>
        <example endspaces=" ">
          <pre xml:space="preserve">
            \begin
Default handler: &lbrace;
            equation
Default handler: &rbrace;
             \sqrt
Default handler: &lbrace;
            \sum_
Default handler: &lbrace;
            0\leq k
            <
             n
Default handler: &rbrace;
             f(k)
Default handler: &rbrace;
             \sqrt
Default handler: &lbrace;
            \vphantom
Default handler: &lbrace;
            \sum
Default handler: &rbrace;
            \smash
Default handler: &lbrace;
            \sum_
Default handler: &lbrace;
            0\leq k
            <
             n
Default handler: &rbrace;
Default handler: &rbrace;
             f(k)
Default handler: &rbrace;
             \end
Default handler: &lbrace;
            equation
Default handler: &rbrace;
          </pre>
        </example>
        <para>
          Note the use of
          <code>
            \vphantom
          </code>
           to give the
          <code>
            \sqrt
          </code>
           command an argument with the height of the
          <code>
            \sum
          </code>
           (
          <pxref label="_005cphantom-_0026-_005cvphantom-_0026-_005chphantom">
            <xrefnodename>
              \phantom
              &
               \vphantom
              &
               \hphantom
            </xrefnodename>
          </pxref>
          ).
        </para>
        <para>
          While most often used in mathematics, the
          <code>
            \smash
          </code>
           command can appear in other contexts. However, it doesn
Default handler: &textrsquo;
          t change into horizontal mode. So if it starts a paragraph then you should first put a
          <code>
            \leavevmode
          </code>
          , as in the bottom line below.
        </para>
        <example endspaces=" ">
          <pre xml:space="preserve">
            Text above. \smash
Default handler: &lbrace;
            smashed, no indent
Default handler: &rbrace;
             % no paragraph indent \leavevmode\smash
Default handler: &lbrace;
            smashed, with indent
Default handler: &rbrace;
             % usual paragraph indent
          </pre>
        </example>
        <cindex index="cp" spaces=" ">
          <indexterm index="cp" number="752">
            <r>
              package
            </r>
            ,
            <code>
              mathtools
            </code>
          </indexterm>
        </cindex>
        <cindex index="cp" spaces=" ">
          <indexterm index="cp" number="753">
            <code>
              mathtools
            </code>
            <r>
              package
            </r>
          </indexterm>
        </cindex>
        <para>
          The package
          <code>
            mathtools
          </code>
           has operators that provide even finer control over smashing a subformula box.
        </para>
      </subsection>
      <node name="_005cphantom-_0026-_005cvphantom-_0026-_005chphantom" spaces=" ">
        <nodename>
          \phantom
          &
           \vphantom
          &
           \hphantom
        </nodename>
        <nodenext automatic="on">
          \mathstrut
        </nodenext>
        <nodeprev automatic="on">
          \smash
        </nodeprev>
        <nodeup automatic="on">
          Spacing in math mode
        </nodeup>
      </node>
      <subsection spaces=" ">
        <sectiontitle>
          <code>
            \phantom
          </code>
          &
          <code>
            \vphantom
          </code>
          &
          <code>
            \hphantom
          </code>
        </sectiontitle>
        <anchor name="_005cphantom">
          \phantom
        </anchor>
        <anchor name="_005cvphantom">
          \vphantom
        </anchor>
        <anchor name="_005chphantom">
          \hphantom
        </anchor>
        <findex index="fn" spaces=" ">
          <indexterm index="fn" number="929" mergedindex="cp">
            \phantom
          </indexterm>
        </findex>
        <findex index="fn" spaces=" ">
          <indexterm index="fn" number="930" mergedindex="cp">
            \vphantom
          </indexterm>
        </findex>
        <findex index="fn" spaces=" ">
          <indexterm index="fn" number="931" mergedindex="cp">
            \hphantom
          </indexterm>
        </findex>
        <cindex index="cp" spaces=" ">
          <indexterm index="cp" number="754">
            spacing, math mode
          </indexterm>
        </cindex>
        <cindex index="cp" spaces=" ">
          <indexterm index="cp" number="755">
            horizontal spacing
          </indexterm>
        </cindex>
        <cindex index="cp" spaces=" ">
          <indexterm index="cp" number="756">
            vertical spacing
          </indexterm>
        </cindex>
        <cindex index="cp" spaces=" ">
          <indexterm index="cp" number="757">
            math mode, spacing
          </indexterm>
        </cindex>
        <cindex index="cp" spaces=" ">
          <indexterm index="cp" number="758">
            invisible character
          </indexterm>
        </cindex>
        <cindex index="cp" spaces=" ">
          <indexterm index="cp" number="759">
            character, invisible
          </indexterm>
        </cindex>
        <para>
          Synopsis:
        </para>
        <example endspaces=" ">
          <pre xml:space="preserve">
            \phantom
Default handler: &lbrace;
            <var>
              subformula
            </var>
Default handler: &rbrace;
          </pre>
        </example>
        <para>
          or
        </para>
        <example endspaces=" ">
          <pre xml:space="preserve">
            \vphantom
Default handler: &lbrace;
            <var>
              subformula
            </var>
Default handler: &rbrace;
          </pre>
        </example>
        <para>
          or
        </para>
        <example endspaces=" ">
          <pre xml:space="preserve">
            \hphantom
Default handler: &lbrace;
            <var>
              subformula
            </var>
Default handler: &rbrace;
          </pre>
        </example>
        <para>
          The
          <code>
            \phantom
          </code>
           command creates a box with the same height, depth, and width as
          <var>
            subformula
          </var>
          , but empty. That is, this command causes
Default handler: &latex;
           to typeset the space but not fill it with the material. Here
Default handler: &latex;
           will put a blank line that is the correct width for the answer, but will not show that answer.
        </para>
        <example endspaces=" ">
          <pre xml:space="preserve">
            \begin
Default handler: &lbrace;
            displaymath
Default handler: &rbrace;
             \int x^2\,dx=\mbox
Default handler: &lbrace;
            \underline
Default handler: &lbrace;
            $\phantom
Default handler: &lbrace;
            (1/3)x^3+C
Default handler: &rbrace;
            $
Default handler: &rbrace;
Default handler: &rbrace;
             \end
Default handler: &lbrace;
            displaymath
Default handler: &rbrace;
          </pre>
        </example>
        <para>
          The
          <code>
            \vphantom
          </code>
           variant produces an invisible box with the same vertical size as
          <var>
            subformula
          </var>
          , the same height and depth, but having zero width. And
          <code>
            \hphantom
          </code>
           makes a box with the same width as
          <var>
            subformula
          </var>
           but with zero height and depth.
        </para>
        <para>
          In this example, the tower of exponents in the second summand expression is so tall that
Default handler: &tex;
           places this expression further down than its default. Without adjustment, the two summand expressions would be at different levels. The
          <code>
            \vphantom
          </code>
           in the first expression tells
Default handler: &tex;
           to leave as much vertical room as it does for the tower, so the two expressions come out at the same level.
        </para>
        <example endspaces=" ">
          <pre xml:space="preserve">
            \begin
Default handler: &lbrace;
            displaymath
Default handler: &rbrace;
             \sum_
Default handler: &lbrace;
            j\in\
Default handler: &lbrace;
            0,\ldots\, 10\
Default handler: &rbrace;
            \vphantom
Default handler: &lbrace;
            3^
Default handler: &lbrace;
            3^
Default handler: &lbrace;
            3^j
Default handler: &rbrace;
Default handler: &rbrace;
Default handler: &rbrace;
Default handler: &rbrace;
             \sum_
Default handler: &lbrace;
            i\in\
Default handler: &lbrace;
            0,\ldots\, 3^
Default handler: &lbrace;
            3^
Default handler: &lbrace;
            3^j
Default handler: &rbrace;
Default handler: &rbrace;
            \
Default handler: &rbrace;
Default handler: &rbrace;
             i\cdot j \end
Default handler: &lbrace;
            displaymath
Default handler: &rbrace;
          </pre>
        </example>
        <para>
          These commands are often used in conjunction with
          <code>
            \smash
          </code>
          .
          <xref label="_005csmash">
            <xrefnodename>
              \smash
            </xrefnodename>
          </xref>
          , which includes another example of
          <code>
            \vphantom
          </code>
          .
        </para>
        <cindex index="cp" spaces=" ">
          <indexterm index="cp" number="760">
            <r>
              package
            </r>
            ,
            <code>
              mathtools
            </code>
          </indexterm>
        </cindex>
        <cindex index="cp" spaces=" ">
          <indexterm index="cp" number="761">
            <code>
              mathtools
            </code>
            <r>
              package
            </r>
          </indexterm>
        </cindex>
        <para>
          The three phantom commands appear often but note that
Default handler: &latex;
           provides a suite of other commands to work with box sizes that may be more convenient, including
          <code>
            \makebox
          </code>
           (
          <pxref label="_005cmbox-_0026-_005cmakebox">
            <xrefnodename>
              \mbox
              &
               \makebox
            </xrefnodename>
          </pxref>
          ) as well as
          <code>
            \settodepth
          </code>
           (
          <pxref label="_005csettodepth">
            <xrefnodename>
              \settodepth
            </xrefnodename>
          </pxref>
          ),
          <code>
            \settoheight
          </code>
           (
          <pxref label="_005csettoheight">
            <xrefnodename>
              \settoheight
            </xrefnodename>
          </pxref>
          ), and
          <code>
            \settowidth
          </code>
           (
          <pxref label="_005csettowidth">
            <xrefnodename>
              \settowidth
            </xrefnodename>
          </pxref>
          ). In addition, the
          <code>
            mathtools
          </code>
           package has many commands that offer fine-grained control over spacing.
        </para>
        <cindex index="cp" spaces=" ">
          <indexterm index="cp" number="762">
            <r>
              package
            </r>
            ,
            <code>
              amsmath
            </code>
          </indexterm>
        </cindex>
        <cindex index="cp" spaces=" ">
          <indexterm index="cp" number="763">
            <code>
              amsmath
            </code>
            <r>
              package
            </r>
          </indexterm>
        </cindex>
        <para>
          All three commands produce an ordinary box, without any special mathematics status. So to do something like attaching a superscript you should give it such a status, for example with the
          <code>
            \operatorname
          </code>
           command from the package
          <code>
            amsmath
          </code>
          .
        </para>
        <para>
          While most often used in mathematics, these three can appear in other contexts. However, they don
Default handler: &textrsquo;
          t cause
Default handler: &latex;
           to change into horizontal mode. So if one of these starts a paragraph then you should prefix it with
          <code>
            \leavevmode
          </code>
          .
        </para>
      </subsection>
      <node name="_005cmathstrut" spaces=" ">
        <nodename>
          \mathstrut
        </nodename>
        <nodeprev automatic="on">
          \phantom
          &
           \vphantom
          &
           \hphantom
        </nodeprev>
        <nodeup automatic="on">
          Spacing in math mode
        </nodeup>
      </node>
      <subsection spaces=" ">
        <sectiontitle>
          <code>
            \mathstrut
          </code>
        </sectiontitle>
        <findex index="fn" spaces=" ">
          <indexterm index="fn" number="932" mergedindex="cp">
            <code>
              \mathstrut
            </code>
          </indexterm>
        </findex>
        <cindex index="cp" spaces=" ">
          <indexterm index="cp" number="764">
            spacing, math mode
          </indexterm>
        </cindex>
        <cindex index="cp" spaces=" ">
          <indexterm index="cp" number="765">
            vertical spacing
          </indexterm>
        </cindex>
        <cindex index="cp" spaces=" ">
          <indexterm index="cp" number="766">
            math mode, spacing
          </indexterm>
        </cindex>
        <cindex index="cp" spaces=" ">
          <indexterm index="cp" number="767">
            invisible character
          </indexterm>
        </cindex>
        <cindex index="cp" spaces=" ">
          <indexterm index="cp" number="768">
            character, invisible
          </indexterm>
        </cindex>
        <cindex index="cp" spaces=" ">
          <indexterm index="cp" number="769">
            strut, math
          </indexterm>
        </cindex>
        <para>
          Synopsis:
        </para>
        <example endspaces=" ">
          <pre xml:space="preserve">
            \mathstrut
          </pre>
        </example>
        <para>
          The analogue of
          <code>
            \strut
          </code>
           for mathematics.
          <xref label="_005cstrut">
            <xrefnodename>
              \strut
            </xrefnodename>
          </xref>
          .
        </para>
        <para>
          The input
          <code>
            $\sqrt
Default handler: &lbrace;
            x
Default handler: &rbrace;
             + \sqrt
Default handler: &lbrace;
            x^i
Default handler: &rbrace;
            $
          </code>
           gives output where the second radical is taller than the first. To add extra vertical space without any horizontal space, so that the two have the same height, use
          <code>
            $\sqrt
Default handler: &lbrace;
            x\mathstrut
Default handler: &rbrace;
             + \sqrt
Default handler: &lbrace;
            x^i\mathstrut
Default handler: &rbrace;
            $
          </code>
          .
        </para>
        <para>
          The
          <code>
            \mathstrut
          </code>
           command adds the vertical height of an open parenthesis,
          <code>
            (
          </code>
          , but no horizontal space. It is defined as
          <code>
            \vphantom
Default handler: &lbrace;
            (
Default handler: &rbrace;
          </code>
          , so see
          <ref label="_005cphantom-_0026-_005cvphantom-_0026-_005chphantom">
            <xrefnodename>
              \phantom
              &
               \vphantom
              &
               \hphantom
            </xrefnodename>
          </ref>
           for more. An advantage over
          <code>
            \strut
          </code>
           is that
          <code>
            \mathstrut
          </code>
           adds no depth, which is often the right thing for formulas. Using the height of an open parenthesis is just a convention; for complete control over the amount of space, use
          <code>
            \rule
          </code>
           with a width of zero.
          <xref label="_005crule">
            <xrefnodename>
              \rule
            </xrefnodename>
          </xref>
          .
        </para>
      </subsection>
    </section>
    <node name="Math-styles" spaces=" ">
      <nodename>
        Math styles
      </nodename>
      <nodenext automatic="on">
        Math miscellany
      </nodenext>
      <nodeprev automatic="on">
        Spacing in math mode
      </nodeprev>
      <nodeup automatic="on">
        Math formulas
      </nodeup>
    </node>
    <section spaces=" ">
      <sectiontitle>
        Math styles
      </sectiontitle>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="770">
          math styles
        </indexterm>
      </cindex>
      <paraDefault handler: &tex;
Default handler: &textrsquo;
>
        s rules for typesetting a formula depend on the context. For example, inside a displayed equation, the input
        <code>
          \sum_
Default handler: &lbrace;
          0\leq i
          <
          n
Default handler: &rbrace;
          k^m=\frac
Default handler: &lbrace;
          n^
Default handler: &lbrace;
          m+1
Default handler: &rbrace;
Default handler: &rbrace;
Default handler: &lbrace;
          m+1
Default handler: &rbrace;
          +\mbox
Default handler: &lbrace;
          lower order terms
Default handler: &rbrace;
        </code>
         will give output with the summation index centered below the summation symbol. But if that input is inline then the summation index is off to the right rather than below, so it won
Default handler: &textrsquo;
        t push the lines apart. Similarly, in a displayed context, the symbols in the numerator and denominator will be larger than for an inline context, and in display math subscripts and superscripts are further apart then they are in inline math.
      </para>
      <paraDefault handler: &tex;
>
         uses four math styles.
      </para>
      <itemize commandarg="bullet" spaces=" " endspaces=" ">
        <itemprepend>
          <formattingcommand command="bullet"/>
        </itemprepend>
        <beforefirstitem>
          <cindex index="cp" spaces=" ">
            <indexterm index="cp" number="771">
              display style
            </indexterm>
          </cindex>
        </beforefirstitem>
        <listitem>
          <prependDefault handler: &bullet;
/>
          <para>
            Display style is for a formula displayed on a line by itself, such as with
            <code>
              \begin
Default handler: &lbrace;
              equation
Default handler: &rbrace;
               ... \end
Default handler: &lbrace;
              equation
Default handler: &rbrace;
            </code>
            .
          </para>
          <cindex index="cp" spaces=" ">
            <indexterm index="cp" number="772">
              text style
            </indexterm>
          </cindex>
        </listitem>
        <listitem>
          <prependDefault handler: &bullet;
/>
          <para>
            Text style is for an inline formula, as with
            <samp>
              so we have $ ... $
            </samp>
            .
          </para>
          <cindex index="cp" spaces=" ">
            <indexterm index="cp" number="773">
              script style
            </indexterm>
          </cindex>
        </listitem>
        <listitem>
          <prependDefault handler: &bullet;
/>
          <para>
            Script style is for parts of a formula in a subscript or superscript.
          </para>
          <cindex index="cp" spaces=" ">
            <indexterm index="cp" number="774">
              scriptscript style
            </indexterm>
          </cindex>
        </listitem>
        <listitem>
          <prependDefault handler: &bullet;
/>
          <para>
            Scriptscript style is for parts of a formula at a second level (or more) of subscript or superscript.
          </para>
        </listitem>
      </itemize>
      <findex index="fn" spaces=" ">
        <indexterm index="fn" number="933" mergedindex="cp">
          \displaystyle
        </indexterm>
      </findex>
      <findex index="fn" spaces=" ">
        <indexterm index="fn" number="934" mergedindex="cp">
          \textstyle
        </indexterm>
      </findex>
      <findex index="fn" spaces=" ">
        <indexterm index="fn" number="935" mergedindex="cp">
          \scriptstyle
        </indexterm>
      </findex>
      <findex index="fn" spaces=" ">
        <indexterm index="fn" number="936" mergedindex="cp">
          \scriptscriptstyle
        </indexterm>
      </findex>
      <paraDefault handler: &tex;
>
         determines a default math style but you can override it with a declaration of
        <code>
          \displaystyle
        </code>
        , or
        <code>
          \textstyle
        </code>
        , or
        <code>
          \scriptstyle
        </code>
        , or
        <code>
          \scriptscriptstyle
        </code>
        .
      </para>
      <para>
        In this example, the
        <samp>
          Arithmetic
        </samp>
         line
Default handler: &textrsquo;
        s fraction will look scrunched.
      </para>
      <example endspaces=" ">
        <pre xml:space="preserve">
          \begin
Default handler: &lbrace;
          tabular
Default handler: &rbrace;
Default handler: &lbrace;
          r|cc
Default handler: &rbrace;
           \textsc
Default handler: &lbrace;
          Name
Default handler: &rbrace;
          &
          \textsc
Default handler: &lbrace;
          Series
Default handler: &rbrace;
          &
          \textsc
Default handler: &lbrace;
          Sum
Default handler: &rbrace;
           \\ \hline Arithmetic
          &
          $a+(a+b)+(a+2b)+\cdots+(a+(n-1)b)$
          &
          $na+(n-1)n\cdot\frac
Default handler: &lbrace;
          b
Default handler: &rbrace;
Default handler: &lbrace;
          2
Default handler: &rbrace;
          $ \\ Geometric
          &
          $a+ab+ab^2+\cdots+ab^
Default handler: &lbrace;
          n-1
Default handler: &rbrace;
          $
          &
          $\displaystyle a\cdot\frac
Default handler: &lbrace;
          1-b^n
Default handler: &rbrace;
Default handler: &lbrace;
          1-b
Default handler: &rbrace;
          $ \\ \end
Default handler: &lbrace;
          tabular
Default handler: &rbrace;
        </pre>
      </example>
      <noindent/>
      <para>
        But because of the
        <code>
          \displaystyle
        </code>
         declaration, the
        <samp>
          Geometric
        </samp>
         line
Default handler: &textrsquo;
        s fraction will be easy to read, with characters the same size as in the rest of the line.
      </para>
      <para>
        Another example is that, compared to the same input without the declaration, the result of
      </para>
      <example endspaces=" ">
        <pre xml:space="preserve">
          we get $\pi=2\cdot
Default handler: &lbrace;
          \displaystyle\int_
Default handler: &lbrace;
          x=0
Default handler: &rbrace;
          ^1 \sqrt
Default handler: &lbrace;
          1-x^2
Default handler: &rbrace;
          \,dx
Default handler: &rbrace;
          $
        </pre>
      </example>
      <noindent/>
      <para>
        will have an integral sign that is much taller. Note that here the
        <code>
          \displaystyle
        </code>
         applies to only part of the formula, and it is delimited by being inside curly braces, as
        <sampDefault handler: &lbrace;
>
          \displaystyle ...
Default handler: &rbrace;
        </samp>
        .
      </para>
      <para>
        The last example is a continued fraction.
      </para>
      <example endspaces=" ">
        <pre xml:space="preserve">
          \begin
Default handler: &lbrace;
          equation
Default handler: &rbrace;
           a_0+\frac
Default handler: &lbrace;
          1
Default handler: &rbrace;
Default handler: &lbrace;
           \displaystyle a_1+\frac
Default handler: &lbrace;
          \mathstrut 1
Default handler: &rbrace;
Default handler: &lbrace;
           \displaystyle a_2+\frac
Default handler: &lbrace;
          \mathstrut 1
Default handler: &rbrace;
Default handler: &lbrace;
           \displaystyle a_3
Default handler: &rbrace;
Default handler: &rbrace;
Default handler: &rbrace;
           \end
Default handler: &lbrace;
          equation
Default handler: &rbrace;
        </pre>
      </example>
      <noindent/>
      <para>
        Without the
        <code>
          \displaystyle
        </code>
         declarations, the denominators would be set in script style and scriptscript style. (The
        <code>
          \mathstrut
        </code>
         improves the height of the denominators;
        <pxref label="_005cmathstrut">
          <xrefnodename>
            \mathstrut
          </xrefnodename>
        </pxref>
        .)
      </para>
    </section>
    <node name="Math-miscellany" spaces=" ">
      <nodename>
        Math miscellany
      </nodename>
      <nodeprev automatic="on">
        Math styles
      </nodeprev>
      <nodeup automatic="on">
        Math formulas
      </nodeup>
    </node>
    <section spaces=" ">
      <sectiontitle>
        Math miscellany
      </sectiontitle>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="775">
          math miscellany
        </indexterm>
      </cindex>
      <paraDefault handler: &latex;
>
         contains a wide variety of mathematics facilities. Here are some that don
Default handler: &textrsquo;
        t fit into other categories.
      </para>
      <menu endspaces=" ">
        <menuentry>
          <menuleadingtext>
            *
          </menuleadingtext>
          <menunode>
            Colon character
            &
             \colon
          </menunode>
          <menuseparator>
            ::
          </menuseparator>
          <menudescription>
            <pre xml:space="preserve">
              Colon.
            </pre>
          </menudescription>
        </menuentry>
        <menuentry>
          <menuleadingtext>
            *
          </menuleadingtext>
          <menunode>
            \*
          </menunode>
          <menuseparator>
            ::
          </menuseparator>
          <menudescription>
            <pre xml:space="preserve">
              Discretionary multiplication.
            </pre>
          </menudescription>
        </menuentry>
        <menuentry>
          <menuleadingtext>
            *
          </menuleadingtext>
          <menunode>
            \frac
          </menunode>
          <menuseparator>
            ::
          </menuseparator>
          <menudescription>
            <pre xml:space="preserve">
              Fraction.
            </pre>
          </menudescription>
        </menuentry>
        <menuentry>
          <menuleadingtext>
            *
          </menuleadingtext>
          <menunode>
            \sqrt
          </menunode>
          <menuseparator>
            ::
          </menuseparator>
          <menudescription>
            <pre xml:space="preserve">
              Radicals.
            </pre>
          </menudescription>
        </menuentry>
        <menuentry>
          <menuleadingtext>
            *
          </menuleadingtext>
          <menunode>
            \stackrel
          </menunode>
          <menuseparator>
            ::
          </menuseparator>
          <menudescription>
            <pre xml:space="preserve">
              Text over a relation.
            </pre>
          </menudescription>
        </menuentry>
      </menu>
      <node name="Colon-character-_0026-_005ccolon" spaces=" ">
        <nodename>
          Colon character
          &
           \colon
        </nodename>
        <nodenext automatic="on">
          \*
        </nodenext>
        <nodeup automatic="on">
          Math miscellany
        </nodeup>
      </node>
      <subsection spaces=" ">
        <sectiontitle>
          Colon character
          <code>
            :
          </code>
          &
          <code>
            \colon
          </code>
        </sectiontitle>
        <anchor name="colon">
          colon
        </anchor>
        <cindex index="cp" spaces=" ">
          <indexterm index="cp" number="776">
            colon character
          </indexterm>
        </cindex>
        <findex index="fn" spaces=" ">
          <indexterm index="fn" number="937" mergedindex="cp">
            :
            <r>
              (for math)
            </r>
          </indexterm>
        </findex>
        <findex index="fn" spaces=" ">
          <indexterm index="fn" number="938" mergedindex="cp">
            \colon
          </indexterm>
        </findex>
        <para>
          Synopsis, one of:
        </para>
        <example endspaces=" ">
          <pre xml:space="preserve">
            : \colon
          </pre>
        </example>
        <para>
          In mathematics, the colon character,
          <code>
            :
          </code>
          , is a relation.
        </para>
        <example endspaces=" ">
          <pre xml:space="preserve">
            With side ratios \( 3:4 \) and \( 4:5 \), the triangle is right.
          </pre>
        </example>
        <cindex index="cp" spaces=" ">
          <indexterm index="cp" number="777">
            <r>
              package
            </r>
            ,
            <code>
              amsmath
            </code>
          </indexterm>
        </cindex>
        <cindex index="cp" spaces=" ">
          <indexterm index="cp" number="778">
            <code>
              amsmath
            </code>
            <r>
              package
            </r>
          </indexterm>
        </cindex>
        <noindent/>
        <para>
          Ordinary
Default handler: &latex;
           defines
          <code>
            \colon
          </code>
           to produce the colon character with the spacing appropriate for punctuation, as in set-builder notation
          <code>
            \
Default handler: &lbrace;
            x\colon 0\leq x
            <
            1\
Default handler: &rbrace;
          </code>
          .
        </para>
        <cindex index="cp" spaces=" ">
          <indexterm index="cp" number="779">
            <r>
              package
            </r>
            ,
            <code>
              amsmath
            </code>
          </indexterm>
        </cindex>
        <cindex index="cp" spaces=" ">
          <indexterm index="cp" number="780">
            <code>
              amsmath
            </code>
            <r>
              package
            </r>
          </indexterm>
        </cindex>
        <para>
          But the widely-used
          <code>
            amsmath
          </code>
           package defines
          <code>
            \colon
          </code>
           for use in the definition of functions
          <code>
            f\colon D\to C
          </code>
          . So if you want the colon character as a punctuation then use
          <code>
            \mathpunct
Default handler: &lbrace;
            :
Default handler: &rbrace;
          </code>
          .
        </para>
      </subsection>
      <node name="_005c_002a" spaces=" ">
        <nodename trailingspaces=" ">
          \*
        </nodename>
        <nodenext automatic="on">
          \frac
        </nodenext>
        <nodeprev automatic="on">
          Colon character
          &
           \colon
        </nodeprev>
        <nodeup automatic="on">
          Math miscellany
        </nodeup>
      </node>
      <subsection spaces=" ">
        <sectiontitle>
          <code>
            \*
          </code>
        </sectiontitle>
        <cindex index="cp" spaces=" ">
          <indexterm index="cp" number="781">
            multiplication, discretionary
          </indexterm>
        </cindex>
        <cindex index="cp" spaces=" ">
          <indexterm index="cp" number="782">
            breaks, multiplication discretionary
          </indexterm>
        </cindex>
        <cindex index="cp" spaces=" ">
          <indexterm index="cp" number="783">
            line breaks, multiplication discretionary
          </indexterm>
        </cindex>
        <cindex index="cp" spaces=" ">
          <indexterm index="cp" number="784">
            discretionary breaks, multiplication
          </indexterm>
        </cindex>
        <findex index="fn" spaces=" ">
          <indexterm index="fn" number="939" mergedindex="cp">
            \*
          </indexterm>
        </findex>
        <para>
          Synopsis:
        </para>
        <example endspaces=" ">
          <pre xml:space="preserve">
            \*
          </pre>
        </example>
        <para>
          A multiplication symbol that allows a line break. If there is a break then
Default handler: &latex;
           puts a
          <code>
            \times
          </code>
           symbol,
          <u>
            00D7
          </u>
          , before that break.
        </para>
        <para>
          In
          <code>
            \( A_1\* A_2\* A_3\* A_4 \)
          </code>
          , if there is no line break then
Default handler: &latex;
           outputs it as though it were
          <code>
            \( A_1 A_2 A_3 A_4 \)
          </code>
          . If a line break does happen, for example between the two middle ones, then
Default handler: &latex;
           sets it like
          <code>
            \( A_1 A_2 \times \)
          </code>
          , followed by the break, followed by
          <code>
            \( A_3 A_4 \)
          </code>
          .
        </para>
      </subsection>
      <node name="_005cfrac" spaces=" ">
        <nodename>
          \frac
        </nodename>
        <nodenext automatic="on">
          \sqrt
        </nodenext>
        <nodeprev automatic="on">
          \*
        </nodeprev>
        <nodeup automatic="on">
          Math miscellany
        </nodeup>
      </node>
      <subsection spaces=" ">
        <sectiontitle>
          <code>
            \frac
          </code>
        </sectiontitle>
        <cindex index="cp" spaces=" ">
          <indexterm index="cp" number="785">
            fraction
          </indexterm>
        </cindex>
        <findex index="fn" spaces=" ">
          <indexterm index="fn" number="940" mergedindex="cp">
            \frac
          </indexterm>
        </findex>
        <para>
          Synopsis:
        </para>
        <example endspaces=" ">
          <pre xml:space="preserve">
            \frac
Default handler: &lbrace;
            <var>
              numerator
            </var>
Default handler: &rbrace;
Default handler: &lbrace;
            <var>
              denominator
            </var>
Default handler: &rbrace;
          </pre>
        </example>
        <para>
          Produces the fraction. Used as:
          <code>
            \begin
Default handler: &lbrace;
            displaymath
Default handler: &rbrace;
             \frac
Default handler: &lbrace;
            1
Default handler: &rbrace;
Default handler: &lbrace;
            \sqrt
Default handler: &lbrace;
            2\pi\sigma
Default handler: &rbrace;
Default handler: &rbrace;
             \end
Default handler: &lbrace;
            displaymath
Default handler: &rbrace;
          </code>
          . In inline math mode it comes out small; see the discussion of
          <code>
            \displaystyle
          </code>
           (
          <pxref label="Math-formulas">
            <xrefnodename>
              Math formulas
            </xrefnodename>
          </pxref>
          ).
        </para>
      </subsection>
      <node name="_005csqrt" spaces=" ">
        <nodename>
          \sqrt
        </nodename>
        <nodenext automatic="on">
          \stackrel
        </nodenext>
        <nodeprev automatic="on">
          \frac
        </nodeprev>
        <nodeup automatic="on">
          Math miscellany
        </nodeup>
      </node>
      <subsection spaces=" ">
        <sectiontitle>
          <code>
            \sqrt
          </code>
        </sectiontitle>
        <cindex index="cp" spaces=" ">
          <indexterm index="cp" number="786">
            square root
          </indexterm>
        </cindex>
        <cindex index="cp" spaces=" ">
          <indexterm index="cp" number="787">
            roots
          </indexterm>
        </cindex>
        <cindex index="cp" spaces=" ">
          <indexterm index="cp" number="788">
            radical
          </indexterm>
        </cindex>
        <findex index="fn" spaces=" ">
          <indexterm index="fn" number="941" mergedindex="cp">
            \sqrt
          </indexterm>
        </findex>
        <para>
          Synopsis, one of:
        </para>
        <example endspaces=" ">
          <pre xml:space="preserve">
            \sqrt
Default handler: &lbrace;
            <var>
              arg
            </var>
Default handler: &rbrace;
             \sqrt[
            <var>
              root-number
            </var>
            ]
Default handler: &lbrace;
            <var>
              arg
            </var>
Default handler: &rbrace;
          </pre>
        </example>
        <para>
          The square root, or optionally other roots, of
          <var>
            arg
          </var>
          . The optional argument
          <var>
            root-number
          </var>
           gives the root, i.e., enter the cube root of
          <code>
            x+y
          </code>
           as
          <code>
            \sqrt[3]
Default handler: &lbrace;
            x+y
Default handler: &rbrace;
          </code>
          . The size of the radical grows with that of
          <var>
            arg
          </var>
           (as the height of the radical grows, the angle on the leftmost part gets steeper, until for a tall enough
          <code>
            arg
          </code>
          , it is vertical).
        </para>
        <paraDefault handler: &latex;
>
           has a separate
          <code>
            \surd
          </code>
           symbol for making a square root without
          <var>
            arg
          </var>
           (
          <pxref label="Math-symbols">
            <xrefnodename>
              Math symbols
            </xrefnodename>
          </pxref>
          ).
        </para>
      </subsection>
      <node name="_005cstackrel" spaces=" ">
        <nodename>
          \stackrel
        </nodename>
        <nodeprev automatic="on">
          \sqrt
        </nodeprev>
        <nodeup automatic="on">
          Math miscellany
        </nodeup>
      </node>
      <subsection spaces=" ">
        <sectiontitle>
          <code>
            \stackrel
          </code>
        </sectiontitle>
        <cindex index="cp" spaces=" ">
          <indexterm index="cp" number="789">
            stack math
          </indexterm>
        </cindex>
        <cindex index="cp" spaces=" ">
          <indexterm index="cp" number="790">
            relation, text above
          </indexterm>
        </cindex>
        <findex index="fn" spaces=" ">
          <indexterm index="fn" number="942" mergedindex="cp">
            \stackrel
          </indexterm>
        </findex>
        <para>
          Synopsis:
        </para>
        <example endspaces=" ">
          <pre xml:space="preserve">
            \stackrel
Default handler: &lbrace;
            <var>
              text
            </var>
Default handler: &rbrace;
Default handler: &lbrace;
            <var>
              relation
            </var>
Default handler: &rbrace;
          </pre>
        </example>
        <para>
          Put
          <var>
            text
          </var>
           above
          <var>
            relation
          </var>
          . To put a function name above an arrow enter
          <code>
            \stackrel
Default handler: &lbrace;
            f
Default handler: &rbrace;
Default handler: &lbrace;
            \longrightarrow
Default handler: &rbrace;
          </code>
          .
        </para>
      </subsection>
    </section>
  </chapter>
  <node name="Modes" spaces=" ">
    <nodename>
      Modes
    </nodename>
    <nodenext automatic="on">
      Page styles
    </nodenext>
    <nodeprev automatic="on">
      Math formulas
    </nodeprev>
    <nodeup automatic="on">
      Top
    </nodeup>
  </node>
  <chapter spaces=" ">
    <sectiontitle>
      Modes
    </sectiontitle>
    <cindex index="cp" spaces=" ">
      <indexterm index="cp" number="791">
        modes
      </indexterm>
    </cindex>
    <para>
      As
Default handler: &latex;
       processes your document, at any point it is in one of six modes. They fall into three categories of two each, the horizontal modes, the math modes, and the vertical modes. Some commands only work in one mode or another (in particular, many commands only work in one of the math modes), and error messages will refer to these.
    </para>
    <itemize commandarg="bullet" automaticcommandarg="on" endspaces=" ">
      <itemprepend>
        <formattingcommand command="bullet" automatic="on"/>
      </itemprepend>
      <listitem>
        <prependDefault handler: &bullet;
/>
        <anchor name="modes-paragraph-mode">
          modes paragraph mode
        </anchor>
        <cindex index="cp" spaces=" ">
          <indexterm index="cp" number="792">
            paragraph mode
          </indexterm>
        </cindex>
        <para>
          <dfn>
            Paragraph mode
          </dfn>
           (in plain
Default handler: &tex;
           this is called
          <dfn>
            horizontal mode
          </dfn>
          ) is what
Default handler: &latex;
           is in when processing ordinary text. It breaks the input text into lines and finds the positions of line breaks, so that in vertical mode page breaks can be done. This is the mode
Default handler: &latex;
           is in most of the time.
        </para>
        <cindex index="cp" spaces=" ">
          <indexterm index="cp" number="793">
            left-to-right mode
          </indexterm>
        </cindex>
        <cindex index="cp" spaces=" ">
          <indexterm index="cp" number="794">
            LR mode
          </indexterm>
        </cindex>
        <anchor name="modes-lr-mode">
          modes lr mode
        </anchor>
        <para>
          <dfn>
            LR mode
          </dfn>
           (for left-to-right mode; in plain
Default handler: &tex;
           this is called
          <dfn>
            restricted horizontal mode
          </dfn>
          ) is in effect when
Default handler: &latex;
           starts making a box with an
          <code>
            \mbox
          </code>
           command. As in paragraph mode,
Default handler: &latex;
Default handler: &textrsquo;
          s output is a string of words with spaces between them. Unlike in paragraph mode, in LR mode
Default handler: &latex;
           never starts a new line, it just keeps going from left to right. (Although
Default handler: &latex;
           will not complain that the LR box is too long, when it is finished and next tries to put that box into a line, it might well complain that the finished LR box won
Default handler: &textrsquo;
          t fit there.)
        </para>
      </listitem>
      <listitem>
        <prependDefault handler: &bullet;
/>
        <cindex index="cp" spaces=" ">
          <indexterm index="cp" number="795">
            math mode
          </indexterm>
        </cindex>
        <anchor name="modes-math-mode">
          modes math mode
        </anchor>
        <para>
          <dfn>
            Math mode
          </dfn>
           is when
Default handler: &latex;
           is generating an inline mathematical formula.
        </para>
        <cindex index="cp" spaces=" ">
          <indexterm index="cp" number="796">
            display math mode
          </indexterm>
        </cindex>
        <para>
          <dfn>
            Display math mode
          </dfn>
           is when
Default handler: &latex;
           is generating a displayed mathematical formula. (Displayed formulas differ somewhat from inline ones. One example is that the placement of the subscript on
          <code>
            \int
          </code>
           differs in the two situations.)
        </para>
      </listitem>
      <listitem>
        <prependDefault handler: &bullet;
/>
        <cindex index="cp" spaces=" ">
          <indexterm index="cp" number="797">
            vertical mode
          </indexterm>
        </cindex>
        <anchor name="modes-vertical-mode">
          modes vertical mode
        </anchor>
        <para>
          <dfn>
            Vertical mode
          </dfn>
           is when
Default handler: &latex;
           is building the list of lines and other material making the output page, which comprises insertion of page breaks. This is the mode
Default handler: &latex;
           is in when it starts a document.
        </para>
        <cindex index="cp" spaces=" ">
          <indexterm index="cp" number="798">
            internal vertical mode
          </indexterm>
        </cindex>
        <anchor name="modes-internal-vertical-mode">
          modes internal vertical mode
        </anchor>
        <para>
          <dfn>
            Internal vertical mode
          </dfn>
           is in effect when
Default handler: &latex;
           starts making a
          <code>
            \vbox
          </code>
          . It has not such thing as page breaks, and as such is the vertical analogue of LR mode.
        </para>
      </listitem>
    </itemize>
    <noindent/>
    <para>
      For instance, if you begin a
Default handler: &latex;
       article with
      <samp>
        Let \( x \) be ...
      </samp>
       then these are the modes: first
Default handler: &latex;
       starts every document in vertical mode, then it reads the
      <samp>
        L
      </samp>
       and switches to paragraph mode, then the next switch happens at the
      <samp>
        \(
      </samp>
       where
Default handler: &latex;
       changes to math mode, and then when it leaves the formula it pops back to paragraph mode.
    </para>
    <cindex index="cp" spaces=" ">
      <indexterm index="cp" number="799">
        inner paragraph mode
      </indexterm>
    </cindex>
    <cindex index="cp" spaces=" ">
      <indexterm index="cp" number="800">
        outer paragraph mode
      </indexterm>
    </cindex>
    <anchor name="modes-inner-paragraph-mode">
      modes inner paragraph mode
    </anchor>
    <anchor name="modes-outer-paragraph-mode">
      modes outer paragraph mode
    </anchor>
    <para>
      Paragraph mode has two subcases. If you use a
      <code>
        \parbox
      </code>
       command or a
      <code>
        minipage
      </code>
       then
Default handler: &latex;
       is put into paragraph mode. But it will not put a page break here. Inside one of these boxes, called a
      <dfn>
        parbox
      </dfn>
      ,
Default handler: &latex;
       is in
      <dfn>
        inner paragraph mode
      </dfn>
      . Its more usual situation, where it can put page breaks, is
      <dfn>
        outer paragraph mode
      </dfn>
       (
      <pxref label="Page-breaking">
        <xrefnodename>
          Page breaking
        </xrefnodename>
      </pxref>
      ).
    </para>
    <menu endspaces=" ">
      <menuentry>
        <menuleadingtext>
          *
        </menuleadingtext>
        <menunode>
          \ensuremath
        </menunode>
        <menuseparator>
          ::
        </menuseparator>
        <menudescription>
          <pre xml:space="preserve">
            Ensure that math mode is active.
          </pre>
        </menudescription>
      </menuentry>
    </menu>
    <node name="_005censuremath" spaces=" ">
      <nodename>
        \ensuremath
      </nodename>
      <nodeup automatic="on">
        Modes
      </nodeup>
    </node>
    <section spaces=" ">
      <sectiontitle>
        <code>
          \ensuremath
        </code>
      </sectiontitle>
      <para>
        Synopsis:
      </para>
      <example endspaces=" ">
        <pre xml:space="preserve">
          \ensuremath
Default handler: &lbrace;
          <var>
            formula
          </var>
Default handler: &rbrace;
        </pre>
      </example>
      <para>
        Ensure that
        <var>
          formula
        </var>
         is typeset in math mode.
      </para>
      <para>
        For instance, you can redefine commands that ordinarily can be used only in math mode, so that they can be used both in math and in plain text.
      </para>
      <example endspaces=" ">
        <pre xml:space="preserve">
          \newcommand
Default handler: &lbrace;
          \dx
Default handler: &rbrace;
Default handler: &lbrace;
          \ensuremath
Default handler: &lbrace;
          dx
Default handler: &rbrace;
Default handler: &rbrace;
           In $\int f(x)\, \dx$, the \dx
Default handler: &lbrace;
Default handler: &rbrace;
           is an infinitesimal.
        </pre>
      </example>
      <para>
        Caution: the
        <code>
          \ensuremath
        </code>
         command is useful but not a panacea.
      </para>
      <example endspaces=" ">
        <pre xml:space="preserve">
          \newcommand
Default handler: &lbrace;
          \alf
Default handler: &rbrace;
Default handler: &lbrace;
          \ensuremath
Default handler: &lbrace;
          \alpha
Default handler: &rbrace;
Default handler: &rbrace;
           You get an alpha in text mode: \alf. But compare the correct spacing in $\alf+\alf$ with that in \alf+\alf.
        </pre>
      </example>
      <noindent/>
      <para>
        Best is to typeset math things in a math mode.
      </para>
    </section>
  </chapter>
  <node name="Page-styles" spaces=" ">
    <nodename>
      Page styles
    </nodename>
    <nodenext automatic="on">
      Spaces
    </nodenext>
    <nodeprev automatic="on">
      Modes
    </nodeprev>
    <nodeup automatic="on">
      Top
    </nodeup>
  </node>
  <chapter spaces=" ">
    <sectiontitle>
      Page styles
    </sectiontitle>
    <cindex index="cp" spaces=" ">
      <indexterm index="cp" number="801">
        styles, page
      </indexterm>
    </cindex>
    <cindex index="cp" spaces=" ">
      <indexterm index="cp" number="802">
        page styles
      </indexterm>
    </cindex>
    <para>
      The style of a page determines where
Default handler: &latex;
       places the components of that page, such as headers and footers, and the text body. This includes pages in the main part of the document but also includes special pages such as the title page of a book, a page from an index, or the first page of an article.
    </para>
    <cindex index="cp" spaces=" ">
      <indexterm index="cp" number="803">
        <r>
          package
        </r>
        ,
        <code>
          fancyhdr
        </code>
      </indexterm>
    </cindex>
    <cindex index="cp" spaces=" ">
      <indexterm index="cp" number="804">
        <code>
          fancyhdr
        </code>
        <r>
          package
        </r>
      </indexterm>
    </cindex>
    <para>
      The package
      <code>
        fancyhdr
      </code>
       is commonly used for constructing page styles. See its documentation.
    </para>
    <menu endspaces=" ">
      <menuentry>
        <menuleadingtext>
          *
        </menuleadingtext>
        <menunode>
          \maketitle
        </menunode>
        <menuseparator>
          ::
        </menuseparator>
        <menudescription>
          <pre xml:space="preserve">
            Generate a title page.
          </pre>
        </menudescription>
      </menuentry>
      <menuentry>
        <menuleadingtext>
          *
        </menuleadingtext>
        <menunode>
          \pagenumbering
        </menunode>
        <menuseparator>
          ::
        </menuseparator>
        <menudescription>
          <pre xml:space="preserve">
            Set the style used for page numbers.
          </pre>
        </menudescription>
      </menuentry>
      <menuentry>
        <menuleadingtext>
          *
        </menuleadingtext>
        <menunode>
          \pagestyle
        </menunode>
        <menuseparator>
          ::
        </menuseparator>
        <menudescription>
          <pre xml:space="preserve">
            Change the headings/footings style.
          </pre>
        </menudescription>
      </menuentry>
      <menuentry>
        <menuleadingtext>
          *
        </menuleadingtext>
        <menunode>
          \thispagestyle
        </menunode>
        <menuseparator>
          ::
        </menuseparator>
        <menudescription>
          <pre xml:space="preserve">
            Change the headings/footings style for this page.
          </pre>
        </menudescription>
      </menuentry>
      <menuentry>
        <menuleadingtext>
          *
        </menuleadingtext>
        <menunode>
          \thepage
        </menunode>
        <menuseparator>
          ::
        </menuseparator>
        <menudescription>
          <pre xml:space="preserve">
            Changing page number representation everywhere.
          </pre>
        </menudescription>
      </menuentry>
    </menu>
    <node name="_005cmaketitle" spaces=" ">
      <nodename>
        \maketitle
      </nodename>
      <nodenext automatic="on">
        \pagenumbering
      </nodenext>
      <nodeup automatic="on">
        Page styles
      </nodeup>
    </node>
    <section spaces=" ">
      <sectiontitle>
        <code>
          \maketitle
        </code>
      </sectiontitle>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="805">
          titles, making
        </indexterm>
      </cindex>
      <findex index="fn" spaces=" ">
        <indexterm index="fn" number="943" mergedindex="cp">
          \maketitle
        </indexterm>
      </findex>
      <para>
        Synopsis:
      </para>
      <example endspaces=" ">
        <pre xml:space="preserve">
          \maketitle
        </pre>
      </example>
      <para>
        Generate a title. In the standard classes the title appears on a separate page, except in the
        <code>
          article
        </code>
         class where it is at the top of the first page. (
        <xref label="Document-class-options">
          <xrefnodename>
            Document class options
          </xrefnodename>
        </xref>
        , for information about the
        <code>
          titlepage
        </code>
         document class option.)
      </para>
      <para>
        This example shows
        <code>
          \maketitle
        </code>
         appearing in its usual place, immediately after
        <code>
          \begin
Default handler: &lbrace;
          document
Default handler: &rbrace;
        </code>
        .
      </para>
      <example endspaces=" ">
        <pre xml:space="preserve">
          \documentclass
Default handler: &lbrace;
          article
Default handler: &rbrace;
           \title
Default handler: &lbrace;
          Constructing a Nuclear Reactor Using Only Coconuts
Default handler: &rbrace;
           \author
Default handler: &lbrace;
          Jonas Grumby\thanks
Default handler: &lbrace;
          % With the support of a Ginger Grant from the Roy Hinkley Society.
Default handler: &rbrace;
           \\ Skipper, \textit
Default handler: &lbrace;
          Minnow
Default handler: &rbrace;
           \and Willy Gilligan\thanks
Default handler: &lbrace;
          % Thanks to the Mary Ann Summers foundation and to Thurston and Lovey Howell.
Default handler: &rbrace;
           \\ Mate, \textit
Default handler: &lbrace;
          Minnow
Default handler: &rbrace;
Default handler: &rbrace;
           \date
Default handler: &lbrace;
          1964-Sep-26
Default handler: &rbrace;
           \begin
Default handler: &lbrace;
          document
Default handler: &rbrace;
           \maketitle Just sit right back and you'll hear a tale, a tale of a fateful trip. That started from this tropic port, aboard this tiny ship. The mate was a mighty sailin' man, the Skipper brave and sure. Five passengers set sail that day for a three hour tour. A three hour tour. ...
        </pre>
      </example>
      <para>
        You tell
Default handler: &latex;
         the information used to produce the title by making the following declarations. These must come before the
        <code>
          \maketitle
        </code>
        , either in the preamble or in the document body.
      </para>
      <ftable commandarg="code" spaces=" " endspaces=" ">
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                <indexterm index="fn" number="944" mergedindex="cp">
                  \author
Default handler: &lbrace;
                  <var>
                    name1
                  </var>
                   \and
                  <var>
                    name2
                  </var>
                   \and ...
Default handler: &rbrace;
                </indexterm>
                \author
Default handler: &lbrace;
                <var>
                  name1
                </var>
                 \and
                <var>
                  name2
                </var>
                 \and ...
Default handler: &rbrace;
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <cindex index="cp" spaces=" ">
              <indexterm index="cp" number="806">
                author, for titlepage
              </indexterm>
            </cindex>
            <findex index="fn" spaces=" ">
              <indexterm index="fn" number="945" mergedindex="cp">
                \\
                <r>
                  (for
                  <code>
                    \author
                  </code>
                  )
                </r>
              </indexterm>
            </findex>
            <findex index="fn" spaces=" ">
              <indexterm index="fn" number="946" mergedindex="cp">
                \and
                <r>
                  (for
                  <code>
                    \author
                  </code>
                  )
                </r>
              </indexterm>
            </findex>
            <para>
              Required. Declare the document author or authors. The argument is a list of authors separated by
              <code>
                \and
              </code>
               commands. To separate lines within a single author
Default handler: &textrsquo;
              s entry, for instance to give the author
Default handler: &textrsquo;
              s institution or address, use a double backslash,
              <code>
                \\
              </code>
              . If you omit the
              <code>
                \author
              </code>
               declaration then you get
              <samp>
                LaTeX Warning: No \author given
              </samp>
              .
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                <indexterm index="fn" number="947" mergedindex="cp">
                  \date
Default handler: &lbrace;
                  <var>
                    text
                  </var>
Default handler: &rbrace;
                </indexterm>
                \date
Default handler: &lbrace;
                <var>
                  text
                </var>
Default handler: &rbrace;
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <cindex index="cp" spaces=" ">
              <indexterm index="cp" number="807">
                date, for titlepage
              </indexterm>
            </cindex>
            <para>
              Optional. Declare
              <var>
                text
              </var>
               to be the document
Default handler: &textrsquo;
              s date. The
              <var>
                text
              </var>
               doesn
Default handler: &textrsquo;
              t need to be in a date format; it can be any text at all. If you omit
              <code>
                \date
              </code>
               then
Default handler: &latex;
               uses the current date (
              <pxref label="_005ctoday">
                <xrefnodename>
                  \today
                </xrefnodename>
              </pxref>
              ). To have no date, instead use
              <code>
                \date
Default handler: &lbrace;
Default handler: &rbrace;
              </code>
              .
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                <indexterm index="fn" number="948" mergedindex="cp">
                  \thanks
Default handler: &lbrace;
                  <var>
                    text
                  </var>
Default handler: &rbrace;
                </indexterm>
                \thanks
Default handler: &lbrace;
                <var>
                  text
                </var>
Default handler: &rbrace;
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <cindex index="cp" spaces=" ">
              <indexterm index="cp" number="808">
                thanks, for titlepage
              </indexterm>
            </cindex>
            <cindex index="cp" spaces=" ">
              <indexterm index="cp" number="809">
                credit footnote
              </indexterm>
            </cindex>
            <para>
              Optional. Produce a footnote. You can use it in the author information for acknowledgements as illustrated above, but you can also use it in the title, or anywhere that a footnote mark makes sense. It can be any text at all so you can use it for any purpose, such as to print an email address.
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                <indexterm index="fn" number="949" mergedindex="cp">
                  \title
Default handler: &lbrace;
                  <var>
                    text
                  </var>
Default handler: &rbrace;
                </indexterm>
                \title
Default handler: &lbrace;
                <var>
                  text
                </var>
Default handler: &rbrace;
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <cindex index="cp" spaces=" ">
              <indexterm index="cp" number="810">
                title, for titlepage
              </indexterm>
            </cindex>
            <findex index="fn" spaces=" ">
              <indexterm index="fn" number="950" mergedindex="cp">
                \\
                <r>
                  (for
                  <code>
                    \title
                  </code>
                  )
                </r>
              </indexterm>
            </findex>
            <para>
              Required. Declare
              <var>
                text
              </var>
               to be the title of the document. Get line breaks inside
              <var>
                text
              </var>
               with a double backslash,
              <code>
                \\
              </code>
              . If you omit the
              <code>
                \title
              </code>
               declaration then the
              <code>
                \maketitle
              </code>
               command yields error
              <samp>
                LaTeX Error: No \title given
              </samp>
              .
            </para>
          </tableitem>
        </tableentry>
      </ftable>
      <para>
        To make your own title page,
        <pxref label="titlepage">
          <xrefnodename>
            titlepage
          </xrefnodename>
        </pxref>
        . You can either create this as a one-off or you can include it as part of a renewed
        <code>
          \maketitle
        </code>
         command. Many publishers will provide a class to use in place of
        <code>
          article
        </code>
         that formats the title according to their house requirements.
      </para>
    </section>
    <node name="_005cpagenumbering" spaces=" ">
      <nodename>
        \pagenumbering
      </nodename>
      <nodenext automatic="on">
        \pagestyle
      </nodenext>
      <nodeprev automatic="on">
        \maketitle
      </nodeprev>
      <nodeup automatic="on">
        Page styles
      </nodeup>
    </node>
    <section spaces=" ">
      <sectiontitle>
        <code>
          \pagenumbering
        </code>
      </sectiontitle>
      <findex index="fn" spaces=" ">
        <indexterm index="fn" number="951" mergedindex="cp">
          \pagenumbering
        </indexterm>
      </findex>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="811">
          page numbering style
        </indexterm>
      </cindex>
      <para>
        Synopsis:
      </para>
      <example endspaces=" ">
        <pre xml:space="preserve">
          \pagenumbering
Default handler: &lbrace;
          <var>
            number-style
          </var>
Default handler: &rbrace;
        </pre>
      </example>
      <para>
        Specifies the style of page numbers, and resets the page number. The numbering style is reflected on the page, and also in the table of contents and other page references. This declaration has global scope so its effect is not stopped by an end of group such as a closing brace or an end of environment.
      </para>
      <para>
        By default,
Default handler: &latex;
         numbers pages starting at 1, using Arabic numerals.
      </para>
      <para>
        The argument
        <var>
          number-style
        </var>
         is one of the following (see also
        <ref label="_005calph-_005cAlph-_005carabic-_005croman-_005cRoman-_005cfnsymbol">
          <xrefnodename>
            \alph \Alph \arabic \roman \Roman \fnsymbol
          </xrefnodename>
        </ref>
        ).
      </para>
      <table commandarg="code" spaces=" " endspaces=" ">
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                arabic
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <para>
              Arabic numerals: 1, 2,
Default handler: &dots;
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                roman
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <para>
              lowercase Roman numerals: i, ii,
Default handler: &dots;
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                Roman
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <para>
              uppercase Roman numerals: I, II,
Default handler: &dots;
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                alph
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <para>
              lowercase letters: a, b,
Default handler: &dots;
               If you have more than 26 pages then you get
              <samp>
                LaTeX Error: Counter too large
              </samp>
              .
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                Alph
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <para>
              uppercase letters: A, B,
Default handler: &dots;
               If you have more than 26 pages then you get
              <samp>
                LaTeX Error: Counter too large
              </samp>
              .
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                gobble
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <para>
              no page number is output, though the number is still reset. References to that page also are blank.
            </para>
            <cindex index="cp" spaces=" ">
              <indexterm index="cp" number="812">
                <r>
                  package
                </r>
                ,
                <code>
                  hyperref
                </code>
              </indexterm>
            </cindex>
            <cindex index="cp" spaces=" ">
              <indexterm index="cp" number="813">
                <code>
                  hyperref
                </code>
                <r>
                  package
                </r>
              </indexterm>
            </cindex>
            <para>
              This setting does not work with the popular package
              <code>
                hyperref
              </code>
              , so to omit page numbers you may want to instead use
              <code>
                \pagestyle
Default handler: &lbrace;
                empty
Default handler: &rbrace;
              </code>
               or
              <code>
                \thispagestyle
Default handler: &lbrace;
                empty
Default handler: &rbrace;
              </code>
              .
            </para>
          </tableitem>
        </tableentry>
      </table>
      <para>
        If you want to typeset the page number in some other way, or change where the page number appears on the page, see
Default handler: &nbsp;
        <ref label="_005cpagestyle">
          <xrefnodename>
            \pagestyle
          </xrefnodename>
        </ref>
         (in short: use the
        <code>
          fancyhdr
        </code>
         package). The list above of
Default handler: &latex;
Default handler: &textrsquo;
        s built-in numbering styles cannot be extended.
      </para>
      <para>
        Traditionally, if a document has front matter
Default handler: &textmdash;
        preface, table of contents, etc.
Default handler: &textmdash;
        then it is numbered with lowercase Roman numerals. The main matter of a document uses arabic.
Default handler: &latex;
         implements this, by providing explicit commands for the different parts (
        <pxref label="_005cfrontmatter-_0026-_005cmainmatter-_0026-_005cbackmatter">
          <xrefnodename>
            \frontmatter
            &
             \mainmatter
            &
             \backmatter
          </xrefnodename>
        </pxref>
        ).
      </para>
      <para>
        As an explicit example, before the
        <samp>
          Main
        </samp>
         section the pages are numbered
        <samp>
          a
        </samp>
        , etc. Starting on the page containing the
        <code>
          \pagenumbering
        </code>
         call in that section, the pages are numbered
        <samp>
          1
        </samp>
        , etc.
      </para>
      <example endspaces=" ">
        <pre xml:space="preserve">
          \begin
Default handler: &lbrace;
          document
Default handler: &rbrace;
          \pagenumbering
Default handler: &lbrace;
          alph
Default handler: &rbrace;
           ... \section
Default handler: &lbrace;
          Main
Default handler: &rbrace;
          \pagenumbering
Default handler: &lbrace;
          arabic
Default handler: &rbrace;
           ...
        </pre>
      </example>
      <para>
        If you want to change the value of the page number, then you manipulate the
        <code>
          page
        </code>
         counter (
        <pxref label="Counters">
          <xrefnodename>
            Counters
          </xrefnodename>
        </pxref>
        ).
      </para>
    </section>
    <node name="_005cpagestyle" spaces=" ">
      <nodename>
        \pagestyle
      </nodename>
      <nodenext automatic="on">
        \thispagestyle
      </nodenext>
      <nodeprev automatic="on">
        \pagenumbering
      </nodeprev>
      <nodeup automatic="on">
        Page styles
      </nodeup>
    </node>
    <section spaces=" ">
      <sectiontitle>
        <code>
          \pagestyle
        </code>
      </sectiontitle>
      <findex index="fn" spaces=" ">
        <indexterm index="fn" number="952" mergedindex="cp">
          \pagestyle
        </indexterm>
      </findex>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="814">
          header style
        </indexterm>
      </cindex>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="815">
          footer style
        </indexterm>
      </cindex>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="816">
          running header and footer style
        </indexterm>
      </cindex>
      <para>
        Synopsis:
      </para>
      <example endspaces=" ">
        <pre xml:space="preserve">
          \pagestyle
Default handler: &lbrace;
          <var>
            style
          </var>
Default handler: &rbrace;
        </pre>
      </example>
      <para>
        Declaration that specifies how the page headers and footers are typeset, from the current page onwards.
      </para>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="817">
          <r>
            package
          </r>
          ,
          <code>
            fancyhdr
          </code>
        </indexterm>
      </cindex>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="818">
          <code>
            fancyhdr
          </code>
          <r>
            package
          </r>
        </indexterm>
      </cindex>
      <para>
        A discussion with an example is below. First, however: the package
        <code>
          fancyhdr
        </code>
         is now the standard way to manipulate headers and footers. New documents that need to do anything other than one of the standard options below should use this package. See its documentation (
        <url>
          <urefurl>
            https://ctan.org/pkg/fancyhdr
          </urefurl>
        </url>
        ).
      </para>
      <para>
        Values for
        <var>
          style
        </var>
        :
      </para>
      <table commandarg="code" spaces=" " endspaces=" ">
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                plain
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <para>
              The header is empty. The footer contains only a page number, centered.
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                empty
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <para>
              The header and footer are both empty.
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                headings
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <para>
              Put running headers and footers on each page. The document style specifies what goes in there; see the discussion below.
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                myheadings
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <para>
              Custom headers, specified via the
              <code>
                \markboth
              </code>
               or the
              <code>
                \markright
              </code>
               commands.
            </para>
          </tableitem>
        </tableentry>
      </table>
      <para>
        Some discussion of the motivation for
Default handler: &latex;
Default handler: &textrsquo;
        s mechanism will help you work with the options
        <code>
          headings
        </code>
         or
        <code>
          myheadings
        </code>
        . The document source below produces an article, two-sided, with the pagestyle
        <code>
          headings
        </code>
        . On this document
Default handler: &textrsquo;
        s left hand pages,
Default handler: &latex;
         wants (in addition to the page number) the title of the current section. On its right hand pages
Default handler: &latex;
         wants the title of the current subsection. When it makes up a page,
Default handler: &latex;
         gets this information from the commands
        <code>
          \leftmark
        </code>
         and
        <code>
          \rightmark
        </code>
        . So it is up to
        <code>
          \section
        </code>
         and
        <code>
          \subsection
        </code>
         to store that information there.
      </para>
      <example endspaces=" ">
        <pre xml:space="preserve">
          \documentclass[twoside]
Default handler: &lbrace;
          article
Default handler: &rbrace;
           \pagestyle
Default handler: &lbrace;
          headings
Default handler: &rbrace;
           \begin
Default handler: &lbrace;
          document
Default handler: &rbrace;
           ... \section
Default handler: &lbrace;
          Section 1
Default handler: &rbrace;
           ... \subsection
Default handler: &lbrace;
          Subsection 1.1
Default handler: &rbrace;
           ... \section
Default handler: &lbrace;
          Section 2
Default handler: &rbrace;
           ... \subsection
Default handler: &lbrace;
          Subsection 2.1
Default handler: &rbrace;
           ... \subsection
Default handler: &lbrace;
          Subsection 2.2
Default handler: &rbrace;
           ...
        </pre>
      </example>
      <noindent/>
      <para>
        Suppose that the second section falls on a left page. Although when the page starts it is in the first section,
Default handler: &latex;
         will put
        <samp>
          Section
Default handler: &nbsp;
          2
        </samp>
         in the left page header. As to the right header, if no subsection starts before the end of the right page then
Default handler: &latex;
         blanks the right hand header. If a subsection does appear before the right page finishes then there are two cases. If at least one subsection starts on the right hand page then
Default handler: &latex;
         will put in the right header the title of the first subsection starting on that right page. If at least one of 2.1, 2.2,
Default handler: &dots;
        , starts on the left page but none starts on the right then
Default handler: &latex;
         puts in the right hand header the title of the last subsection to start, that is, the one in effect during the right hand page.
      </para>
      <para>
        To accomplish this, in a two-sided article,
Default handler: &latex;
         has
        <code>
          \section
        </code>
         issue a command
        <code>
          \markboth
        </code>
        , setting
        <code>
          \leftmark
        </code>
         to
        <samp>
          Section
Default handler: &nbsp;
          2
        </samp>
         and setting
        <code>
          \rightmark
        </code>
         to an empty content. And,
Default handler: &latex;
         has
        <code>
          \subsection
        </code>
         issue a command
        <code>
          \markright
        </code>
        , setting
        <code>
          \rightmark
        </code>
         to
        <samp>
          Subsection
Default handler: &nbsp;
          2.1
        </samp>
        , etc.
      </para>
      <para>
        Here are the descriptions of
        <code>
          \markboth
        </code>
         and
        <code>
          \markright
        </code>
        :
      </para>
      <ftable commandarg="code" spaces=" " endspaces=" ">
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                <indexterm index="fn" number="953" mergedindex="cp">
                  \markboth
Default handler: &lbrace;
                  <var>
                    left-head
                  </var>
Default handler: &rbrace;
Default handler: &lbrace;
                  <var>
                    right-head
                  </var>
Default handler: &rbrace;
                </indexterm>
                \markboth
Default handler: &lbrace;
                <var>
                  left-head
                </var>
Default handler: &rbrace;
Default handler: &lbrace;
                <var>
                  right-head
                </var>
Default handler: &rbrace;
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <para>
              Sets both the right hand and left hand heading information for either a page style of
              <code>
                headings
              </code>
               or
              <code>
                myheadings
              </code>
              . A left hand page heading
              <var>
                left-head
              </var>
               is generated by the last
              <code>
                \markboth
              </code>
               command before the end of the page. A right hand page heading
              <var>
                right-head
              </var>
               is generated by the first
              <code>
                \markboth
              </code>
               or
              <code>
                \markright
              </code>
               that comes on the page if there is one, otherwise by the last one that came before that page.
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                <indexterm index="fn" number="954" mergedindex="cp">
                  \markright
Default handler: &lbrace;
                  <var>
                    right-head
                  </var>
Default handler: &rbrace;
                </indexterm>
                \markright
Default handler: &lbrace;
                <var>
                  right-head
                </var>
Default handler: &rbrace;
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <para>
              Sets the right hand page heading, leaving the left unchanged.
            </para>
          </tableitem>
        </tableentry>
      </ftable>
    </section>
    <node name="_005cthispagestyle" spaces=" ">
      <nodename>
        \thispagestyle
      </nodename>
      <nodenext automatic="on">
        \thepage
      </nodenext>
      <nodeprev automatic="on">
        \pagestyle
      </nodeprev>
      <nodeup automatic="on">
        Page styles
      </nodeup>
    </node>
    <section spaces=" ">
      <sectiontitle>
        <code>
          \thispagestyle
        </code>
      </sectiontitle>
      <findex index="fn" spaces=" ">
        <indexterm index="fn" number="955" mergedindex="cp">
          \thispagestyle
        </indexterm>
      </findex>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="819">
          page style, this page
        </indexterm>
      </cindex>
      <para>
        Synopsis:
      </para>
      <example endspaces=" ">
        <pre xml:space="preserve">
          \thispagestyle
Default handler: &lbrace;
          <var>
            style
          </var>
Default handler: &rbrace;
        </pre>
      </example>
      <para>
        Works in the same way as the
        <code>
          \pagestyle
        </code>
         (
        <pxref label="_005cpagestyle">
          <xrefnodename>
            \pagestyle
          </xrefnodename>
        </pxref>
        ), except that it changes to
        <var>
          style
        </var>
         for the current page only. This declaration has global scope, so its effect is not delimited by braces or environments.
      </para>
      <para>
        Often the first page of a chapter or section has a different style. For example, this
Default handler: &latex;
         book document has the first page of the first chapter in
        <code>
          plain
        </code>
         style, as is the default (
        <pxref label="Page-styles">
          <xrefnodename>
            Page styles
          </xrefnodename>
        </pxref>
        ).
      </para>
      <example endspaces=" ">
        <pre xml:space="preserve">
          \documentclass
Default handler: &lbrace;
          book
Default handler: &rbrace;
           \pagestyle
Default handler: &lbrace;
          headings
Default handler: &rbrace;
           \begin
Default handler: &lbrace;
          document
Default handler: &rbrace;
           \chapter
Default handler: &lbrace;
          First chapter
Default handler: &rbrace;
           ... \chapter
Default handler: &lbrace;
          Second chapter
Default handler: &rbrace;
          \thispagestyle
Default handler: &lbrace;
          empty
Default handler: &rbrace;
           ...
        </pre>
      </example>
      <noindent/>
      <para>
        The
        <code>
          plain
        </code>
         style has a page number on it, centered in the footer. To make the page entirely empty, the command
        <code>
          \thispagestyle
Default handler: &lbrace;
          empty
Default handler: &rbrace;
        </code>
         immediately follows the second
        <code>
          \chapter
        </code>
        .
      </para>
    </section>
    <node name="_005cthepage" spaces=" ">
      <nodename>
        \thepage
      </nodename>
      <nodeprev automatic="on">
        \thispagestyle
      </nodeprev>
      <nodeup automatic="on">
        Page styles
      </nodeup>
    </node>
    <section spaces=" ">
      <sectiontitle>
        <code>
          \thepage
        </code>
      </sectiontitle>
      <findex index="fn" spaces=" ">
        <indexterm index="fn" number="956" mergedindex="cp">
          \thepage
        </indexterm>
      </findex>
      <para>
        If you want to change the appearance of page numbers only in the page headers, for example by adding an ornament, typesetting in small caps, etc., then the
        <code>
          fancyhdr
        </code>
         package, as mentioned in a previous section, is the best approach.
      </para>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="820">
          page number representation
        </indexterm>
      </cindex>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="821">
          table of contents, page numbers in
        </indexterm>
      </cindex>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="822">
          cross-references, page numbers in
        </indexterm>
      </cindex>
      <para>
        On the other hand, you may want to change how page numbers are denoted everywhere, including the table of contents and cross-references, as well as the page headers. In this case, you should redefine
        <code>
          \thepage
        </code>
        , which is the command
Default handler: &latex;
         uses for the representation of page numbers.
      </para>
      <para>
        However,
        <code>
          \thepage
        </code>
         should do any typesetting or other complicated maneuvers, but merely expand to the intended page number representation. The results of a complicated redefinition of
        <code>
          \thepage
        </code>
         are not predictable, but
Default handler: &latex;
Default handler: &textrsquo;
        s report of page numbers in diagnostic messages, at least, will become unusable.
      </para>
      <para>
        There is some discussion of this issue at
        <url>
          <urefurl>
            https://tex.stackexchange.com/questions/687258
          </urefurl>
        </url>
        .
      </para>
    </section>
  </chapter>
  <node name="Spaces" spaces=" ">
    <nodename>
      Spaces
    </nodename>
    <nodenext automatic="on">
      Boxes
    </nodenext>
    <nodeprev automatic="on">
      Page styles
    </nodeprev>
    <nodeup automatic="on">
      Top
    </nodeup>
  </node>
  <chapter spaces=" ">
    <sectiontitle>
      Spaces
    </sectiontitle>
    <cindex index="cp" spaces=" ">
      <indexterm index="cp" number="823">
        spaces
      </indexterm>
    </cindex>
    <cindex index="cp" spaces=" ">
      <indexterm index="cp" number="824">
        white space
      </indexterm>
    </cindex>
    <paraDefault handler: &latex;
>
       has many ways to produce white space, or filled space. Some of these are best suited to mathematical text; for these see
Default handler: &nbsp;
      <ref label="Spacing-in-math-mode">
        <xrefnodename>
          Spacing in math mode
        </xrefnodename>
      </ref>
      .
    </para>
    <menu endspaces=" ">
      <menucomment>
        <pre xml:space="preserve">
          Horizontal space
        </pre>
      </menucomment>
      <menuentry>
        <menuleadingtext>
          *
        </menuleadingtext>
        <menunode>
          \enspace
          &
           \quad
          &
           \qquad
        </menunode>
        <menuseparator>
          ::
        </menuseparator>
        <menudescription>
          <pre xml:space="preserve">
            Traditional horizontal spaces.
          </pre>
        </menudescription>
      </menuentry>
      <menuentry>
        <menuleadingtext>
          *
        </menuleadingtext>
        <menunode>
          \hspace
        </menunode>
        <menuseparator>
          ::
        </menuseparator>
        <menudescription>
          <pre xml:space="preserve">
            Any horizontal space.
          </pre>
        </menudescription>
      </menuentry>
      <menuentry>
        <menuleadingtext>
          *
        </menuleadingtext>
        <menunode>
          \hfill
        </menunode>
        <menuseparator>
          ::
        </menuseparator>
        <menudescription>
          <pre xml:space="preserve">
            Stretchable horizontal space.
          </pre>
        </menudescription>
      </menuentry>
      <menuentry>
        <menuleadingtext>
          *
        </menuleadingtext>
        <menunode>
          \hss
        </menunode>
        <menuseparator>
          ::
        </menuseparator>
        <menudescription>
          <pre xml:space="preserve">
            Infinitely stretchable/shrinkable horizontal space.
          </pre>
        </menudescription>
      </menuentry>
      <menuentry>
        <menuleadingtext>
          *
        </menuleadingtext>
        <menunode>
          \spacefactor
        </menunode>
        <menuseparator>
          ::
        </menuseparator>
        <menudescription>
          <pre xml:space="preserve">
            Stretchability of following space
          </pre>
        </menudescription>
      </menuentry>
      <menuentry>
        <menuleadingtext>
          *
        </menuleadingtext>
        <menunode>
          \(SPACE)
        </menunode>
        <menuseparator>
          ::
        </menuseparator>
        <menudescription>
          <pre xml:space="preserve">
            Backslash-space, and explicit space.
          </pre>
        </menudescription>
      </menuentry>
      <menuentry>
        <menuleadingtext>
          *
        </menuleadingtext>
        <menunode>
          ~
        </menunode>
        <menuseparator>
          ::
        </menuseparator>
        <menudescription>
          <pre xml:space="preserve">
            Tie, an unbreakable space.
          </pre>
        </menudescription>
      </menuentry>
      <menuentry>
        <menuleadingtext>
          *
        </menuleadingtext>
        <menunode>
          \thinspace
          &
           \negthinspace
        </menunode>
        <menuseparator>
          ::
        </menuseparator>
        <menudescription>
          <pre xml:space="preserve">
            One-sixth of an em, and negative one-sixth.
          </pre>
        </menudescription>
      </menuentry>
      <menuentry>
        <menuleadingtext>
          *
        </menuleadingtext>
        <menunode>
          \/
        </menunode>
        <menuseparator>
          ::
        </menuseparator>
        <menudescription>
          <pre xml:space="preserve">
            Italic correction.
          </pre>
        </menudescription>
      </menuentry>
      <menuentry>
        <menuleadingtext>
          *
        </menuleadingtext>
        <menunode>
          \hrulefill
          &
           \dotfill
        </menunode>
        <menuseparator>
          ::
        </menuseparator>
        <menudescription>
          <pre xml:space="preserve">
            Stretchable horizontal rule or dots.
          </pre>
        </menudescription>
      </menuentry>
      <menucomment>
        <pre xml:space="preserve">
           Vertical space
        </pre>
      </menucomment>
      <menuentry>
        <menuleadingtext>
          *
        </menuleadingtext>
        <menunode>
          \bigskip
          &
           \medskip
          &
           \smallskip
        </menunode>
        <menuseparator>
          ::
        </menuseparator>
        <menudescription>
          <pre xml:space="preserve">
            Inter-paragraph vertical spaces.
          </pre>
        </menudescription>
      </menuentry>
      <menuentry>
        <menuleadingtext>
          *
        </menuleadingtext>
        <menunode>
          \bigbreak
          &
           \medbreak
          &
           \smallbreak
        </menunode>
        <menuseparator>
          ::
        </menuseparator>
        <menudescription>
          <pre xml:space="preserve">
            Inter-paragraph space and page breaks.
          </pre>
        </menudescription>
      </menuentry>
      <menuentry>
        <menuleadingtext>
          *
        </menuleadingtext>
        <menunode>
          \strut
        </menunode>
        <menuseparator>
          ::
        </menuseparator>
        <menudescription>
          <pre xml:space="preserve">
            Ensure height of a line.
          </pre>
        </menudescription>
      </menuentry>
      <menuentry>
        <menuleadingtext>
          *
        </menuleadingtext>
        <menunode>
          \vspace
        </menunode>
        <menuseparator>
          ::
        </menuseparator>
        <menudescription>
          <pre xml:space="preserve">
            Vertical space.
          </pre>
        </menudescription>
      </menuentry>
      <menuentry>
        <menuleadingtext>
          *
        </menuleadingtext>
        <menunode>
          \vfill
        </menunode>
        <menuseparator>
          ::
        </menuseparator>
        <menudescription>
          <pre xml:space="preserve">
            Stretchable vertical space.
          </pre>
        </menudescription>
      </menuentry>
      <menuentry>
        <menuleadingtext>
          *
        </menuleadingtext>
        <menunode>
          \addvspace
        </menunode>
        <menuseparator>
          ::
        </menuseparator>
        <menudescription>
          <pre xml:space="preserve">
            Add arbitrary vertical space if needed.
          </pre>
        </menudescription>
      </menuentry>
    </menu>
    <node name="_005censpace-_0026-_005cquad-_0026-_005cqquad" spaces=" ">
      <nodename>
        \enspace
        &
         \quad
        &
         \qquad
      </nodename>
      <nodenext automatic="on">
        \hspace
      </nodenext>
      <nodeup automatic="on">
        Spaces
      </nodeup>
    </node>
    <section spaces=" ">
      <sectiontitle>
        <code>
          \enspace
        </code>
        &
        <code>
          \quad
        </code>
        &
        <code>
          \qquad
        </code>
      </sectiontitle>
      <anchor name="_005censpace">
        \enspace
      </anchor>
      <anchor name="_005cquad">
        \quad
      </anchor>
      <anchor name="_005cqquad">
        \qquad
      </anchor>
      <findex index="fn" spaces=" ">
        <indexterm index="fn" number="957" mergedindex="cp">
          \enspace
        </indexterm>
      </findex>
      <findex index="fn" spaces=" ">
        <indexterm index="fn" number="958" mergedindex="cp">
          \quad
        </indexterm>
      </findex>
      <findex index="fn" spaces=" ">
        <indexterm index="fn" number="959" mergedindex="cp">
          \qquad
        </indexterm>
      </findex>
      <para>
        Synopsis, one of:
      </para>
      <example endspaces=" ">
        <pre xml:space="preserve">
          \enspace \quad \qquad
        </pre>
      </example>
      <para>
        Insert a horizontal space of 1/2
        <dmn>
          em
        </dmn>
        , 1
        <dmn>
          em
        </dmn>
        , or 2
        <dmn>
          em
        </dmn>
        . The em is a length defined by a font designer, often thought of as being the width of a capital
Default handler: &nbsp;
        M. One advantage of describing space in ems is that it can be more portable across documents than an absolute measurement such as points (
        <pxref label="Lengths_002fem">
          <xrefnodename>
            Lengths/em
          </xrefnodename>
        </pxref>
        ).
      </para>
      <para>
        This puts a suitable gap between two graphics.
      </para>
      <example endspaces=" ">
        <pre xml:space="preserve">
          \begin
Default handler: &lbrace;
          center
Default handler: &rbrace;
           \includegraphics
Default handler: &lbrace;
          womensmile.png
Default handler: &rbrace;
          % \qquad\includegraphics
Default handler: &lbrace;
          mensmile.png
Default handler: &rbrace;
           \end
Default handler: &lbrace;
          center
Default handler: &rbrace;
        </pre>
      </example>
      <noindent/>
      <para>
        <xref label="Spacing-in-math-mode">
          <xrefnodename>
            Spacing in math mode
          </xrefnodename>
        </xref>
        , for
        <code>
          \quad
        </code>
         and
        <code>
          \qquad
        </code>
        . These are lengths from centuries of typesetting and so may be a better choice in many circumstances than arbitrary lengths, such as you get with
        <code>
          \hspace
        </code>
        .
      </para>
    </section>
    <node name="_005chspace" spaces=" ">
      <nodename>
        \hspace
      </nodename>
      <nodenext automatic="on">
        \hfill
      </nodenext>
      <nodeprev automatic="on">
        \enspace
        &
         \quad
        &
         \qquad
      </nodeprev>
      <nodeup automatic="on">
        Spaces
      </nodeup>
    </node>
    <section spaces=" ">
      <sectiontitle>
        <code>
          \hspace
        </code>
      </sectiontitle>
      <findex index="fn" spaces=" ">
        <indexterm index="fn" number="960" mergedindex="cp">
          \hspace
        </indexterm>
      </findex>
      <para>
        Synopsis, one of:
      </para>
      <example endspaces=" ">
        <pre xml:space="preserve">
          \hspace
Default handler: &lbrace;
          <var>
            length
          </var>
Default handler: &rbrace;
           \hspace*
Default handler: &lbrace;
          <var>
            length
          </var>
Default handler: &rbrace;
        </pre>
      </example>
      <para>
        Insert the amount
        <var>
          length
        </var>
         of horizontal space. The
        <var>
          length
        </var>
         can be positive, negative, or zero; adding a negative amount of space is like backspacing. It is a rubber length, that is, it may contain a
        <code>
          plus
        </code>
         or
        <code>
          minus
        </code>
         component, or both (
        <pxref label="Lengths">
          <xrefnodename>
            Lengths
          </xrefnodename>
        </pxref>
        ). Because the space is stretchable and shrinkable, it is sometimes called
        <dfn>
          glue
        </dfn>
        .
      </para>
      <para>
        This makes a line with
        <samp>
          Name:
        </samp>
         an inch from the right margin.
      </para>
      <example endspaces=" ">
        <pre xml:space="preserve">
          \noindent\makebox[\linewidth][r]
Default handler: &lbrace;
          Name:\hspace
Default handler: &lbrace;
          1in
Default handler: &rbrace;
Default handler: &rbrace;
        </pre>
      </example>
      <para>
        The
        <code>
          *
        </code>
        -form inserts horizontal space that is non-discardable. More precisely, when
Default handler: &tex;
         breaks a paragraph into lines any white space
Default handler: &textmdash;
        glues and kerns
Default handler: &textmdash;
        that come at a line break are discarded. The
        <code>
          *
        </code>
        -form avoids that (technically, it adds a non-discardable invisible item in front of the space).
      </para>
      <para>
        In this example
      </para>
      <example endspaces=" ">
        <pre xml:space="preserve">
          \parbox
Default handler: &lbrace;
          0.8\linewidth
Default handler: &rbrace;
Default handler: &lbrace;
          % Fill in each blank: Four \hspace*
Default handler: &lbrace;
          1in
Default handler: &rbrace;
           and seven years ago our fathers brought forth on this continent, a new \hspace*
Default handler: &lbrace;
          1in
Default handler: &rbrace;
          , conceived in \hspace*
Default handler: &lbrace;
          1in
Default handler: &rbrace;
          , and dedicated to the proposition that all men are created \hspace*
Default handler: &lbrace;
          1in
Default handler: &rbrace;
          .
Default handler: &rbrace;
        </pre>
      </example>
      <noindent/>
      <para>
        the 1
Default handler: &nbsp;
        inch blank following
        <samp>
          conceived in
        </samp>
         falls at the start of a line. If you erase the
        <code>
          *
        </code>
         then
Default handler: &latex;
         discards the blank.
      </para>
      <para>
        Here, the
        <code>
          \hspace
        </code>
         separates the three graphics.
      </para>
      <example endspaces=" ">
        <pre xml:space="preserve">
          \begin
Default handler: &lbrace;
          center
Default handler: &rbrace;
           \includegraphics
Default handler: &lbrace;
          lion.png
Default handler: &rbrace;
          % comment keeps out extra space \hspace
Default handler: &lbrace;
          1cm minus 0.25cm
Default handler: &rbrace;
          \includegraphics
Default handler: &lbrace;
          tiger.png
Default handler: &rbrace;
          % \hspace
Default handler: &lbrace;
          1cm minus 0.25cm
Default handler: &rbrace;
          \includegraphics
Default handler: &lbrace;
          bear.png
Default handler: &rbrace;
           \end
Default handler: &lbrace;
          center
Default handler: &rbrace;
        </pre>
      </example>
      <noindent/>
      <para>
        Because the argument to each
        <code>
          \hspace
        </code>
         has
        <code>
          minus 0.25cm
        </code>
        , each can shrink a little if the three figures are too wide. But each space won
Default handler: &textrsquo;
        t shrink more than 0.25
        <dmn>
          cm
        </dmn>
         (
        <pxref label="Lengths">
          <xrefnodename>
            Lengths
          </xrefnodename>
        </pxref>
        ).
      </para>
    </section>
    <node name="_005chfill" spaces=" ">
      <nodename>
        \hfill
      </nodename>
      <nodenext automatic="on">
        \hss
      </nodenext>
      <nodeprev automatic="on">
        \hspace
      </nodeprev>
      <nodeup automatic="on">
        Spaces
      </nodeup>
    </node>
    <section spaces=" ">
      <sectiontitle>
        <code>
          \hfill
        </code>
      </sectiontitle>
      <findex index="fn" spaces=" ">
        <indexterm index="fn" number="961" mergedindex="cp">
          \hfill
        </indexterm>
      </findex>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="825">
          stretch, infinite horizontal
        </indexterm>
      </cindex>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="826">
          infinite horizontal stretch
        </indexterm>
      </cindex>
      <para>
        Synopsis:
      </para>
      <example endspaces=" ">
        <pre xml:space="preserve">
          \hfill
        </pre>
      </example>
      <para>
        Produce a rubber length which has no natural space but that can stretch horizontally as far as needed (
        <pxref label="Lengths">
          <xrefnodename>
            Lengths
          </xrefnodename>
        </pxref>
        ).
      </para>
      <para>
        This creates a one-line paragraph with
        <samp>
          Name:
        </samp>
         on the left side of the page and
        <samp>
          Quiz One
        </samp>
         on the right.
      </para>
      <example endspaces=" ">
        <pre xml:space="preserve">
          \noindent Name:\hfill Quiz One
        </pre>
      </example>
      <findex index="fn" spaces=" ">
        <indexterm index="fn" number="962" mergedindex="cp">
          \fill
        </indexterm>
      </findex>
      <para>
        The
        <code>
          \hfill
        </code>
         command is equivalent to
        <code>
          \hspace
Default handler: &lbrace;
          \fill
Default handler: &rbrace;
        </code>
         and so the space can be discarded at line breaks. To avoid that instead use
        <code>
          \hspace*
Default handler: &lbrace;
          \fill
Default handler: &rbrace;
        </code>
         (
        <pxref label="_005chspace">
          <xrefnodename>
            \hspace
          </xrefnodename>
        </pxref>
        ).
      </para>
      <para>
        Here the graphs are evenly spaced in the middle of the figure.
      </para>
      <example endspaces=" ">
        <pre xml:space="preserve">
          \newcommand*
Default handler: &lbrace;
          \vcenteredhbox
Default handler: &rbrace;
          [1]
Default handler: &lbrace;
          \begin
Default handler: &lbrace;
          tabular
Default handler: &rbrace;
Default handler: &lbrace;
Default handler: &arobase;
Default handler: &lbrace;
Default handler: &rbrace;
          c
Default handler: &arobase;
Default handler: &lbrace;
Default handler: &rbrace;
Default handler: &rbrace;
          #1\end
Default handler: &lbrace;
          tabular
Default handler: &rbrace;
Default handler: &rbrace;
           ... \begin
Default handler: &lbrace;
          figure
Default handler: &rbrace;
           \hspace*
Default handler: &lbrace;
          \fill
Default handler: &rbrace;
          % \vcenteredhbox
Default handler: &lbrace;
          \includegraphics
Default handler: &lbrace;
          graph0.png
Default handler: &rbrace;
Default handler: &rbrace;
          % \hfill\vcenteredhbox
Default handler: &lbrace;
          \includegraphics
Default handler: &lbrace;
          graph1.png
Default handler: &rbrace;
Default handler: &rbrace;
          % \hspace*
Default handler: &lbrace;
          \fill
Default handler: &rbrace;
          % \caption
Default handler: &lbrace;
          Comparison of two graphs
Default handler: &rbrace;
           \label
Default handler: &lbrace;
          fig:twographs
Default handler: &rbrace;
           \end
Default handler: &lbrace;
          figure
Default handler: &rbrace;
        </pre>
      </example>
      <noindent/>
      <para>
        Note the
        <code>
          \hspace*
        </code>
Default handler: &textrsquo;
        s where the space could otherwise be dropped.
      </para>
    </section>
    <node name="_005chss" spaces=" ">
      <nodename>
        \hss
      </nodename>
      <nodenext automatic="on">
        \spacefactor
      </nodenext>
      <nodeprev automatic="on">
        \hfill
      </nodeprev>
      <nodeup automatic="on">
        Spaces
      </nodeup>
    </node>
    <section spaces=" ">
      <sectiontitle>
        <code>
          \hss
        </code>
      </sectiontitle>
      <findex index="fn" spaces=" ">
        <indexterm index="fn" number="963" mergedindex="cp">
          \hss
        </indexterm>
      </findex>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="827">
          horizontal space
        </indexterm>
      </cindex>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="828">
          horizontal space, stretchable
        </indexterm>
      </cindex>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="829">
          space, inserting horizontal
        </indexterm>
      </cindex>
      <para>
        Synopsis:
      </para>
      <example endspaces=" ">
        <pre xml:space="preserve">
          \hss
        </pre>
      </example>
      <para>
        Produce a horizontal space that is infinitely shrinkable as well as infinitely stretchable (this command is a
Default handler: &tex;
         primitive).
Default handler: &latex;
         authors should reach first for the
        <code>
          \makebox
        </code>
         command to get the effects of
        <code>
          \hss
        </code>
         (
        <pxref label="_005cmbox-_0026-_005cmakebox">
          <xrefnodename>
            \mbox
            &
             \makebox
          </xrefnodename>
        </pxref>
        ).
      </para>
      <para>
        Here, the first line
Default handler: &textrsquo;
        s
        <code>
          \hss
        </code>
         makes the Z stick out to the right, overwriting the Y. In the second line the Z sticks out to the left, overwriting the X.
      </para>
      <example endspaces=" ">
        <pre xml:space="preserve">
          X\hbox to 0pt
Default handler: &lbrace;
          Z\hss
Default handler: &rbrace;
          Y X\hbox to 0pt
Default handler: &lbrace;
          \hss Z
Default handler: &rbrace;
          Y
        </pre>
      </example>
      <noindent/>
      <para>
        Without the
        <code>
          \hss
        </code>
         you get something like
        <samp>
          Overfull \hbox (6.11111pt too wide) detected at line 20
        </samp>
        .
      </para>
    </section>
    <node name="_005cspacefactor" spaces=" ">
      <nodename>
        \spacefactor
      </nodename>
      <nodenext automatic="on">
        \(SPACE)
      </nodenext>
      <nodeprev automatic="on">
        \hss
      </nodeprev>
      <nodeup automatic="on">
        Spaces
      </nodeup>
    </node>
    <section spaces=" ">
      <sectiontitle>
        <code>
          \spacefactor
        </code>
      </sectiontitle>
      <para>
        Synopsis:
      </para>
      <example endspaces=" ">
        <pre xml:space="preserve">
          \spacefactor=
          <var>
            integer
          </var>
        </pre>
      </example>
      <findex index="fn" spaces=" ">
        <indexterm index="fn" number="964" mergedindex="cp">
          \spacefactor
        </indexterm>
      </findex>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="830">
          space factor
        </indexterm>
      </cindex>
      <para>
        Influence
Default handler: &latex;
Default handler: &textrsquo;
        s stretching and shrinking of glue. Few user-level documents need to use this.
      </para>
      <para>
        While
Default handler: &latex;
         is laying out the material, it may stretch or shrink the gaps between words. (This space is not a character; it is called the
        <dfn>
          interword glue
        </dfn>
        ;
        <pxref label="_005chspace">
          <xrefnodename>
            \hspace
          </xrefnodename>
        </pxref>
        ). The
        <code>
          \spacefactor
        </code>
         parameter (a
Default handler: &tex;
         primitive) allows you to, for instance, have the space after a period stretch more than the space after a word-ending letter.
      </para>
      <para>
        After
Default handler: &latex;
         places each character, or rule or other box, it sets a parameter called the
        <dfn>
          space factor
        </dfn>
        . If the next thing in the input is a space then this parameter affects how much stretching or shrinking can happen. A space factor that is larger than the normal value means that the glue can stretch more and shrink less. Normally, the space factor is 1000. This value is in effect following most characters, and any non-character box or math formula. But it is 3000 after a period, exclamation mark, or question mark, 2000 after a colon, 1500 after a semicolon, 1250 after a comma, and 0 after a right parenthesis or bracket, or closing double quote or single quote. Finally, it is 999 after a capital letter.
      </para>
      <para>
        If the space factor
Default handler: &nbsp;
        <var>
          f
        </var>
         is 1000 then the glue gap will be the font
Default handler: &textrsquo;
        s normal space value (for Computer Modern Roman 10 point this is 3.3333
        <dmn>
          pt
        </dmn>
        ). Otherwise, if the space factor
        <var>
          f
        </var>
         is greater than 2000 then
Default handler: &tex;
         adds the font
Default handler: &textrsquo;
        s extra space value (for Computer Modern Roman 10 point this is 1.11111
        <dmn>
          pt
        </dmn>
        ), and then the font
Default handler: &textrsquo;
        s normal stretch value is multiplied by
        <math>
          f /1000
        </math>
         and the normal shrink value is multiplied by
        <math>
          1000/f
        </math>
         (for Computer Modern Roman 10 point these are 1.66666 and 1.11111
        <dmn>
          pt
        </dmn>
        ).
      </para>
      <para>
        For example, consider the period ending
        <samp>
          A man's best friend is his dog.
        </samp>
        . After it,
Default handler: &tex;
         puts in a fixed extra space, and also allows the glue to stretch 3 times as much and shrink 1/3 as much, as the glue after
        <code>
          friend
        </code>
         or any of the other words, since they are not followed by punctuation.
      </para>
      <para>
        The rules for space factors are even more complex because they play additional roles. In practice, there are two consequences. First, if a period or other punctuation is followed by a right parenthesis or bracket, or right single or double quote then the spacing effect of that period carries through those characters (that is, the following glue will have increased stretch and shrink). Second, if punctuation comes after a capital letter then the normal effect of the period is does not happen, so you get an ordinary space. This second case also affects abbreviations that do not end in a capital letter (
        <pxref label="_005c_0040">
          <xrefnodename>
            \
Default handler: &arobase;
          </xrefnodename>
        </pxref>
        ).
      </para>
      <para>
        You can only use
        <code>
          \spacefactor
        </code>
         in paragraph mode or LR mode (
        <pxref label="Modes">
          <xrefnodename>
            Modes
          </xrefnodename>
        </pxref>
        ). You can see the current value with
        <code>
          \the\spacefactor
        </code>
         or
        <code>
          \showthe\spacefactor
        </code>
        .
      </para>
      <para>
        Finally, not especially related to
        <code>
          \spacefactor
        </code>
         itself: if you get errors like
        <samp>
          You can't use `\spacefactor' in vertical mode
        </samp>
        , or
        <samp>
          You can't use `\spacefactor' in math mode.
        </samp>
        , or
        <samp>
          Improper \spacefactor
        </samp>
         then you have probably tried to redefine an internal command.
        <xref label="_005cmakeatletter-_0026-_005cmakeatother">
          <xrefnodename>
            \makeatletter
            &
             \makeatother
          </xrefnodename>
        </xref>
        .
      </para>
      <menu endspaces=" ">
        <menuentry>
          <menuleadingtext>
            *
          </menuleadingtext>
          <menunode>
            \
Default handler: &arobase;
          </menunode>
          <menuseparator>
            ::
          </menuseparator>
          <menudescription>
            <pre xml:space="preserve">
              Distinguish sentence-ending periods from abbreviations.
            </pre>
          </menudescription>
        </menuentry>
        <menuentry>
          <menuleadingtext>
            *
          </menuleadingtext>
          <menunode>
            \frenchspacing
            &
             \nonfrenchspacing
          </menunode>
          <menuseparator>
            ::
          </menuseparator>
          <menudescription>
            <pre xml:space="preserve">
              Equal interword and inter-sentence space.
            </pre>
          </menudescription>
        </menuentry>
        <menuentry>
          <menuleadingtext>
            *
          </menuleadingtext>
          <menunode>
            \normalsfcodes
          </menunode>
          <menuseparator>
            ::
          </menuseparator>
          <menudescription>
            <pre xml:space="preserve">
              Restore space factor settings to the default.
            </pre>
          </menudescription>
        </menuentry>
      </menu>
      <node name="_005c_0040" spaces=" ">
        <nodename trailingspaces=" ">
          \
Default handler: &arobase;
        </nodename>
        <nodenext automatic="on">
          \frenchspacing
          &
           \nonfrenchspacing
        </nodenext>
        <nodeup automatic="on">
          \spacefactor
        </nodeup>
      </node>
      <subsection spaces=" ">
        <sectiontitle>
          <code>
            \
Default handler: &arobase;
          </code>
        </sectiontitle>
        <findex index="fn" spaces=" ">
          <indexterm index="fn" number="965" mergedindex="cp">
            \
Default handler: &arobase;
          </indexterm>
        </findex>
        <findex index="fn" spaces=" ">
          <indexterm index="fn" number="966" mergedindex="cp">
            at-sign
          </indexterm>
        </findex>
        <cindex index="cp" spaces=" ">
          <indexterm index="cp" number="831">
            period, sentence-ending
          </indexterm>
        </cindex>
        <cindex index="cp" spaces=" ">
          <indexterm index="cp" number="832">
            period, abbreviation-ending
          </indexterm>
        </cindex>
        <cindex index="cp" spaces=" ">
          <indexterm index="cp" number="833">
            period, spacing after
          </indexterm>
        </cindex>
        <cindex index="cp" spaces=" ">
          <indexterm index="cp" number="834">
            sentence-ending punctuation
          </indexterm>
        </cindex>
        <cindex index="cp" spaces=" ">
          <indexterm index="cp" number="835">
            non-sentence-ending punctuation
          </indexterm>
        </cindex>
        <cindex index="cp" spaces=" ">
          <indexterm index="cp" number="836">
            punctuation, sentence-ending
          </indexterm>
        </cindex>
        <anchor name="_005cAT">
          \AT
        </anchor>
Default handler: <!-- c old name -->
        <para>
          Synopsis:
        </para>
        <example endspaces=" ">
          <pre xml:space="preserve">
            <var>
              capital-letter
            </var>
            \
Default handler: &arobase;
            .
          </pre>
        </example>
        <para>
          Treat a period (or other punctuation) as sentence-ending, where
Default handler: &latex;
           would otherwise think it is part of an abbreviation.
Default handler: &latex;
           thinks that a period ends an abbreviation if the period comes after a capital letter, and otherwise thinks the period ends the sentence.
        </para>
        <para>
          This example shows the two cases to remember.
        </para>
        <example endspaces=" ">
          <pre xml:space="preserve">
            The songs \textit
Default handler: &lbrace;
            Red Guitar
Default handler: &rbrace;
            , etc.\ are by Loudon Wainwright~III\
Default handler: &arobase;
            .
          </pre>
        </example>
        <noindent/>
        <para>
          The first period ends the abbreviation
          <samp>
            etc.
          </samp>
           but not the sentence. The backslash-space,
          <code>
            \
          </code>
          , produces a mid-sentence space. The second period ends the sentence, despite it being preceded by a capital letter. We tell
Default handler: &latex;
           that it ends the sentence by putting
          <code>
            \
Default handler: &arobase;
          </code>
           before it.
        </para>
        <cindex index="cp" spaces=" ">
          <indexterm index="cp" number="837">
            right parentheses/quotes, and spacing
          </indexterm>
        </cindex>
        <cindex index="cp" spaces=" ">
          <indexterm index="cp" number="838">
            parentheses and ends of sentences
          </indexterm>
        </cindex>
        <cindex index="cp" spaces=" ">
          <indexterm index="cp" number="839">
            quotes and ends of sentences
          </indexterm>
        </cindex>
        <para>
          So: if you have a capital letter followed by a period that ends the sentence, then put
          <code>
            \
Default handler: &arobase;
          </code>
           before the period. This holds even if there is an intervening right parenthesis or bracket, or right single or double quote, because the spacing effect of that period carries through those characters. For example, this
        </para>
        <example endspaces=" ">
          <pre xml:space="preserve">
            Use the \textit
Default handler: &lbrace;
            Instructional Practices Guide
Default handler: &rbrace;
            , (a book by the MAA)\
Default handler: &arobase;
            .
          </pre>
        </example>
        <noindent/>
        <para>
          will have correct inter-sentence spacing after the period.
        </para>
        <para>
          The
          <code>
            \
Default handler: &arobase;
          </code>
           command is only for text modes. If you use it outside of a text mode then you get the error
          <samp>
            You can't use `\spacefactor' in vertical mode
          </samp>
           (
          <pxref label="Modes">
            <xrefnodename>
              Modes
            </xrefnodename>
          </pxref>
          ).
        </para>
        <cindex index="cp" spaces=" ">
          <indexterm index="cp" number="840">
            question marks, ending a sentence
          </indexterm>
        </cindex>
        <cindex index="cp" spaces=" ">
          <indexterm index="cp" number="841">
            exclamation points, ending a sentence
          </indexterm>
        </cindex>
        <para>
          All the above applies equally to question marks and exclamation points as periods, since all are sentence-ending punctuation, and
Default handler: &latex;
           increases the space after each in the same way, when they end a sentence.
Default handler: &latex;
           also increases spacing after colon, semicolon, and comma characters (
          <pxref label="_005cspacefactor">
            <xrefnodename>
              \spacefactor
            </xrefnodename>
          </pxref>
          ).
        </para>
        <para>
          In addition: the converse case is a period (or other punctuation) that does not end a sentence. For that case, follow the period with a backslash-space, (
          <code>
            \
          </code>
          ), or a tie, (
          <code>
            ~
          </code>
          ), or
          <code>
            \
Default handler: &arobase;
          </code>
          . Examples are
          <code>
            Nat.\ Acad.\ Science
          </code>
          , and
          <code>
            Mr.~Bean
          </code>
          , and
          <code>
            (manure, etc.\
Default handler: &arobase;
            ) for sale
          </code>
           (note in the last one that the
          <code>
            \
Default handler: &arobase;
          </code>
           comes after the period but before the closing parenthesis).
        </para>
      </subsection>
      <node name="_005cfrenchspacing-_0026-_005cnonfrenchspacing" spaces=" ">
        <nodename>
          \frenchspacing
          &
           \nonfrenchspacing
        </nodename>
        <nodenext automatic="on">
          \normalsfcodes
        </nodenext>
        <nodeprev automatic="on">
          \
Default handler: &arobase;
        </nodeprev>
        <nodeup automatic="on">
          \spacefactor
        </nodeup>
      </node>
      <anchor name="_005cfrenchspacing">
        \frenchspacing
      </anchor>
Default handler: <!-- c old node name -->
      <subsection spaces=" ">
        <sectiontitle>
          <code>
            \frenchspacing
          </code>
          &
          <code>
            \nonfrenchspacing
          </code>
        </sectiontitle>
        <anchor name="_005cnonfrenchspacing">
          \nonfrenchspacing
        </anchor>
        <findex index="fn" spaces=" ">
          <indexterm index="fn" number="967" mergedindex="cp">
            \frenchspacing
          </indexterm>
        </findex>
        <findex index="fn" spaces=" ">
          <indexterm index="fn" number="968" mergedindex="cp">
            \nonfrenchspacing
          </indexterm>
        </findex>
        <cindex index="cp" spaces=" ">
          <indexterm index="cp" number="842">
            spacing, inter-sentence
          </indexterm>
        </cindex>
        <para>
          Synopsis, one of:
        </para>
        <example endspaces=" ">
          <pre xml:space="preserve">
            \frenchspacing \nonfrenchspacing
          </pre>
        </example>
        <para>
          <code>
            \frenchspacing
          </code>
           causes
Default handler: &latex;
           to make spacing after all punctuation, including periods, be the same as the space between words in the middle of a sentence.
          <code>
            \nonfrenchspacing
          </code>
           switches back to the default handling in which spacing after most punctuation stretches or shrinks differently than a word space (
          <pxref label="_005cspacefactor">
            <xrefnodename>
              \spacefactor
            </xrefnodename>
          </pxref>
          ).
        </para>
        <para>
          In American English, the typesetting tradition is to adjust, typically increasing, the space after punctuation more than the space between words that are in the middle of a sentence. Declaring
          <code>
            \frenchspacing
          </code>
           (the command is inherited from plain
Default handler: &tex;
          ) switches to the tradition that all spaces are treated equally.
        </para>
        <para>
          If your
Default handler: &latex;
           document specifies the language being used, for example with the
          <code>
            babel
          </code>
           package, the necessary settings should be taken care of for you.
        </para>
      </subsection>
      <node name="_005cnormalsfcodes" spaces=" ">
        <nodename>
          \normalsfcodes
        </nodename>
        <nodeprev automatic="on">
          \frenchspacing
          &
           \nonfrenchspacing
        </nodeprev>
        <nodeup automatic="on">
          \spacefactor
        </nodeup>
      </node>
      <subsection spaces=" ">
        <sectiontitle>
          <code>
            \normalsfcodes
          </code>
        </sectiontitle>
        <findex index="fn" spaces=" ">
          <indexterm index="fn" number="969" mergedindex="cp">
            \normalsfcodes
          </indexterm>
        </findex>
        <cindex index="cp" spaces=" ">
          <indexterm index="cp" number="843">
            spacing, inter-sentence
          </indexterm>
        </cindex>
        <para>
          Synopsis:
        </para>
        <example endspaces=" ">
          <pre xml:space="preserve">
            \normalsfcodes
          </pre>
        </example>
        <para>
          Reset the
Default handler: &latex;
           space factors to the default values (
          <pxref label="_005cspacefactor">
            <xrefnodename>
              \spacefactor
            </xrefnodename>
          </pxref>
          ).
        </para>
      </subsection>
    </section>
    <node name="_005c_0028SPACE_0029" spaces=" ">
      <nodename trailingspaces=" ">
        \(SPACE)
      </nodename>
      <nodenext automatic="on">
        ~
      </nodenext>
      <nodeprev automatic="on">
        \spacefactor
      </nodeprev>
      <nodeup automatic="on">
        Spaces
      </nodeup>
    </node>
    <section spaces=" ">
      <sectiontitle>
        Backslash-space,
        <code>
          \
        </code>
      </sectiontitle>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="844">
          \
          <key>
            NEWLINE
          </key>
        </indexterm>
      </cindex>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="845">
          \
          <key>
            SPACE
          </key>
        </indexterm>
      </cindex>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="846">
          \
          <key>
            TAB
          </key>
        </indexterm>
      </cindex>
      <findex index="fn" spaces=" ">
        <indexterm index="fn" number="970" mergedindex="cp">
          \
          <w/>
          <r>
            (backslash-space)
          </r>
        </indexterm>
      </findex>
      <findex index="fn" spaces=" ">
        <indexterm index="fn" number="971" mergedindex="cp">
          \
          <key>
            SPACE
          </key>
        </indexterm>
      </findex>
      <para>
        This section refers to the command consisting of two characters, a backslash followed by a space. Synopsis:
      </para>
      <example endspaces=" ">
        <pre xml:space="preserve">
          \
          <w/>
        </pre>
      </example>
      <para>
        Produce a space. By default it produces white space of length 3.33333
        <dmn>
          pt
        </dmn>
         plus 1.66666
        <dmn>
          pt
        </dmn>
         minus 1.11111
        <dmn>
          pt
        </dmn>
        .
      </para>
      <para>
        When you type one or more blanks between words,
Default handler: &latex;
         produces whitespace that is different than an explicit space. This illustrates:
      </para>
      <example endspaces=" ">
        <pre xml:space="preserve">
          \begin
Default handler: &lbrace;
          tabular
Default handler: &rbrace;
Default handler: &lbrace;
          rl
Default handler: &rbrace;
           One blank:
          &
           makes some space \\ Three blanks:
          &
           in a row \\ Three spaces:
          &
          \ \ \ in a row \\ \end
Default handler: &lbrace;
          tabular
Default handler: &rbrace;
        </pre>
      </example>
      <noindent/>
      <para>
        On the first line
Default handler: &latex;
         puts some space after the colon. On the second line
Default handler: &latex;
         collapses the three blanks to output one whitespace, so you end with the same space after the colon as in the first line.
Default handler: &latex;
         would similarly collapse them to a single whitespace if one, two or all of the three blanks were replaced by a tab, or by a newline. However, the bottom line asks for three spaces so the white area is wider. That is, the backslash-space command creates a fixed amount of horizontal space. (Note that you can define a horizontal space of any width at all with
        <code>
          \hspace
        </code>
        ; see
Default handler: &nbsp;
        <ref label="_005chspace">
          <xrefnodename>
            \hspace
          </xrefnodename>
        </ref>
        .)
      </para>
      <para>
        The backslash-space command has two main uses. It is often used after control sequences to keep them from gobbling the blank that follows, as after
        <code>
          \TeX
        </code>
         in
        <code>
          \TeX\ (or \LaTeX)
        </code>
        . (But using curly braces has the advantage of still working whether the next character is a blank or any other non-letter, as in
        <code>
          \TeX
Default handler: &lbrace;
Default handler: &rbrace;
           (or \LaTeX
Default handler: &lbrace;
Default handler: &rbrace;
          )
        </code>
         in which
        <codeDefault handler: &lbrace;
Default handler: &rbrace;
/>
         can be added after
        <code>
          \LaTeX
        </code>
         as well as after
        <code>
          \TeX
        </code>
        .) The other common use is that it marks a period as ending an abbreviation instead of ending a sentence, as in
        <code>
          Prof.\ Smith
        </code>
         or
        <code>
          Jones et al.\ (1993)
        </code>
         (
        <pxref label="_005c_0040">
          <xrefnodename>
            \
Default handler: &arobase;
          </xrefnodename>
        </pxref>
        ).
      </para>
      <para>
        Under normal circumstances,
        <code>
          \
        </code>
        <key>
          TAB
        </key>
         and
        <code>
          \
        </code>
        <key>
          NEWLINE
        </key>
         are equivalent to backslash-space,
        <code>
          \
        </code>
        .
      </para>
      <anchor name="Leading-blanks">
        Leading blanks
      </anchor>
      <para>
        In order to allow source code indentation, under normal circumstances,
Default handler: &tex;
         ignores leading blanks in a line. So the following prints
        <samp>
          one word
        </samp>
        :
      </para>
      <example endspaces=" ">
        <pre xml:space="preserve">
          one word
        </pre>
      </example>
      <noindent/>
      <para>
        where the white space between
        <samp>
          one
        </samp>
         and
        <samp>
          word
        </samp>
         is produced by the newline after
        <samp>
          one
        </samp>
        , not by the space before
        <samp>
          word
        </samp>
        .
      </para>
Default handler: <!-- c @PkgIndex{xspace} -->
Default handler: <!-- c Some individual commands, notably those defined with the @package{xspace}, -->
Default handler: <!-- c package do not follow the standard behavior. -->
    </section>
    <node name="_007e" spaces=" ">
      <nodename>
        ~
      </nodename>
      <nodenext automatic="on">
        \thinspace
        &
         \negthinspace
      </nodenext>
      <nodeprev automatic="on">
        \(SPACE)
      </nodeprev>
      <nodeup automatic="on">
        Spaces
      </nodeup>
    </node>
    <section spaces=" ">
      <sectiontitle>
        <code>
          ~
        </code>
        ,
        <code>
          \nobreakspace
        </code>
      </sectiontitle>
      <findex index="fn" spaces=" ">
        <indexterm index="fn" number="972" mergedindex="cp">
          ~
        </indexterm>
      </findex>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="847">
          tie
        </indexterm>
      </cindex>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="848">
          space, unbreakable
        </indexterm>
      </cindex>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="849">
          hard space
        </indexterm>
      </cindex>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="850">
          unbreakable space
        </indexterm>
      </cindex>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="851">
          NBSP
        </indexterm>
      </cindex>
      <para>
        Synopsis:
      </para>
      <example endspaces=" ">
        <pre xml:space="preserve">
          <var>
            before
          </var>
          ~
          <var>
            after
          </var>
        </pre>
      </example>
      <findex index="fn" spaces=" ">
        <indexterm index="fn" number="973" mergedindex="cp">
          \nobreakspace
        </indexterm>
      </findex>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="852">
          no-break space, Unicode U+00A0
        </indexterm>
      </cindex>
      <para>
        The
        <dfn>
          tie
        </dfn>
         character,
        <code>
          ~
        </code>
        , produces a space between
        <var>
          before
        </var>
         and
        <var>
          after
        </var>
         at which the line will not be broken. By default the white space has length 3.33333
        <dmn>
          pt
        </dmn>
         plus 1.66666
        <dmn>
          pt
        </dmn>
         minus 1.11111
        <dmn>
          pt
        </dmn>
         (
        <pxref label="Lengths">
          <xrefnodename>
            Lengths
          </xrefnodename>
        </pxref>
        ). The command
        <code>
          \nobreakspace
        </code>
         and the Unicode input character U+00A0 (also in many 8-bit encodings) are synonyms.
      </para>
Default handler: <!-- c This paragraph is not translated to French, as the French translation -->
Default handler: <!-- c uses a term that means ``unbreakable''. -->
      <para>
        Note that the word
        <samp>
          tie
        </samp>
         has this meaning in the
Default handler: &tex;
        /Texinfo community; this differs from the typographic term
Default handler: &textldquo;
        tie
Default handler: &textrdquo;
        , which is a diacritic in the shape of an arc, called a
Default handler: &textldquo;
        tie-after
Default handler: &textrdquo;
         accent in
        <cite>
          The
Default handler: &tex;
          book
        </cite>
        .
      </para>
      <para>
        Here
Default handler: &latex;
         will not break the line between the final two words:
      </para>
      <example endspaces=" ">
        <pre xml:space="preserve">
          Thanks to Prof.~Lerman.
        </pre>
      </example>
      <noindent/>
      <para>
        In addition, despite the period,
Default handler: &latex;
         does not use the end-of-sentence spacing (
        <pxref label="_005c_0040">
          <xrefnodename>
            \
Default handler: &arobase;
          </xrefnodename>
        </pxref>
        ).
      </para>
      <para>
        Ties prevent a line break where that could cause confusion. They also still allow hyphenation (of either of the tied words), so they are generally preferable to putting consecutive words in an
        <code>
          \mbox
        </code>
         (
        <pxref label="_005cmbox-_0026-_005cmakebox">
          <xrefnodename>
            \mbox
            &
             \makebox
          </xrefnodename>
        </pxref>
        ).
      </para>
      <para>
        Exactly where ties should be used is something of a matter of taste, sometimes alarmingly dogmatic taste, among readers. Nevertheless, here are some usage models, many of them from
        <cite>
          The
Default handler: &tex;
          book
        </cite>
        .
      </para>
      <itemize commandarg="bullet" spaces=" " endspaces=" ">
        <itemprepend>
          <formattingcommand command="bullet"/>
        </itemprepend>
        <listitem>
          <prependDefault handler: &bullet;
/>
          <para>
            Between an enumerator label and number, such as in references:
            <code>
              Chapter~12
            </code>
            , or
            <code>
              Theorem~\ref
Default handler: &lbrace;
              th:Wilsons
Default handler: &rbrace;
            </code>
            , or
            <code>
              Figure~\ref
Default handler: &lbrace;
              fig:KGraph
Default handler: &rbrace;
            </code>
            .
          </para>
        </listitem>
        <listitem>
          <prependDefault handler: &bullet;
/>
          <para>
            When cases are enumerated inline:
            <code>
              (b)~Show that $f(x)$ is (1)~continuous, and (2)~bounded
            </code>
            .
          </para>
          <cindex index="cp" spaces=" ">
            <indexterm index="cp" number="853">
              <r>
                package
              </r>
              ,
              <code>
                siunitx
              </code>
            </indexterm>
          </cindex>
          <cindex index="cp" spaces=" ">
            <indexterm index="cp" number="854">
              <code>
                siunitx
              </code>
              <r>
                package
              </r>
            </indexterm>
          </cindex>
        </listitem>
        <listitem>
          <prependDefault handler: &bullet;
/>
          <para>
            Between a number and its unit:
            <code>
              $745.7.8$~watts
            </code>
             (the
            <code>
              siunitx
            </code>
             package has a special facility for this) or
            <code>
              144~eggs
            </code>
            . This includes between a month and day number in a date:
            <code>
              October~12
            </code>
             or
            <code>
              12~Oct
            </code>
            . In general, in any expressions where numbers and abbreviations or symbols are separated by a space:
            <code>
              AD~565
            </code>
            , or
            <code>
              2:50~pm
            </code>
            , or
            <code>
              Boeing~747
            </code>
            , or
            <code>
              268~Plains Road
            </code>
            , or
            <code>
              \$$1.4$~billion
            </code>
            . Other common choices here are a thin space (
            <pxref label="_005cthinspace-_0026-_005cnegthinspace">
              <xrefnodename>
                \thinspace
                &
                 \negthinspace
              </xrefnodename>
            </pxref>
            ) and no space at all.
          </para>
        </listitem>
        <listitem>
          <prependDefault handler: &bullet;
/>
          <para>
            When mathematical phrases are rendered in words:
            <code>
              equals~$n$
            </code>
            , or
            <code>
              less than~$\epsilon$
            </code>
            , or
            <code>
              given~$X$
            </code>
            , or
            <code>
              modulo~$p^e$ for all large~$n$
            </code>
             (but compare
            <code>
              is~$15$
            </code>
             with
            <code>
              is $15$~times the height
            </code>
            ). Between mathematical symbols in apposition with nouns:
            <code>
              dimension~$d$
            </code>
             or
            <code>
              function~$f(x)$
            </code>
             (but compare
            <code>
              with length $l$~or more
            </code>
            ). When a symbol is a tightly bound object of a preposition:
            <code>
              of~$x$
            </code>
            , or
            <code>
              from $0$ to~$1$
            </code>
            , or
            <code>
              in common with~$m$
            </code>
            .
          </para>
        </listitem>
        <listitem>
          <prependDefault handler: &bullet;
/>
          <para>
            Between symbols in series:
            <code>
              $1$,~$2$, or~$3$
            </code>
             or
            <code>
              $1$,~$2$, \ldots,~$n$
            </code>
            .
          </para>
        </listitem>
        <listitem>
          <prependDefault handler: &bullet;
/>
          <para>
            Between a person
Default handler: &textrsquo;
            s given names and between multiple surnames:
            <code>
              Donald~E. Knuth
            </code>
            , or
            <code>
              Luis~I. Trabb~Pardo
            </code>
            , or
            <code>
              Charles~XII
            </code>
Default handler: &textmdash;
            but you must give
Default handler: &tex;
             places to break the line so you might do
            <code>
              Charles Louis Xavier~Joseph de~la Vall\'ee~Poussin
            </code>
            .
          </para>
        </listitem>
      </itemize>
    </section>
    <node name="_005cthinspace-_0026-_005cnegthinspace" spaces=" ">
      <nodename>
        \thinspace
        &
         \negthinspace
      </nodename>
      <nodenext automatic="on">
        \/
      </nodenext>
      <nodeprev automatic="on">
        ~
      </nodeprev>
      <nodeup automatic="on">
        Spaces
      </nodeup>
    </node>
    <section spaces=" ">
      <sectiontitle>
        <code>
          \thinspace
        </code>
        &
        <code>
          \negthinspace
        </code>
      </sectiontitle>
      <anchor name="_005cthinspace">
        \thinspace
      </anchor>
      <anchor name="_005cnegthinspace">
        \negthinspace
      </anchor>
      <findex index="fn" spaces=" ">
        <indexterm index="fn" number="974" mergedindex="cp">
          \thinspace
        </indexterm>
      </findex>
      <findex index="fn" spaces=" ">
        <indexterm index="fn" number="975" mergedindex="cp">
          \negthinspace
        </indexterm>
      </findex>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="855">
          thin space
        </indexterm>
      </cindex>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="856">
          space, thin
        </indexterm>
      </cindex>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="857">
          thin space, negative
        </indexterm>
      </cindex>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="858">
          space, negative thin
        </indexterm>
      </cindex>
      <para>
        Synopsis, one of:
      </para>
      <example endspaces=" ">
        <pre xml:space="preserve">
          \thinspace \negthinspace
        </pre>
      </example>
      <para>
        These produce unbreakable and unstretchable spaces of 1/6
        <dmn>
          em
        </dmn>
         and -1/6
        <dmn>
          em
        </dmn>
        , respectively. These are the text mode equivalents of
        <code>
          \,
        </code>
         and
        <code>
          \!
        </code>
         (
        <pxref label="Spacing-in-math-mode_002f_005cthinspace">
          <xrefnodename>
            Spacing in math mode/\thinspace
          </xrefnodename>
        </pxref>
        ).
      </para>
      <para>
        You can use
        <code>
          \,
        </code>
         as a synonym for
        <code>
          \thinspace
        </code>
         in text mode.
      </para>
      <para>
        One common use of
        <code>
          \thinspace
        </code>
         is as the space between nested quotes:
      </para>
      <example endspaces=" ">
        <pre xml:space="preserve">
          Killick replied, ``I heard the Captain say, `Ahoy there.'\thinspace''
        </pre>
      </example>
      <noindent/>
      <para>
        Another use is that some style guides call for a
        <code>
          \thinspace
        </code>
         between an ellipsis and a sentence ending period (other style guides, think the three dots and/or four dots are plenty). Another style-specific use is between initials, as in
        <code>
          D.\thinspace E.\ Knuth
        </code>
        .
      </para>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="859">
          <r>
            package
          </r>
          ,
          <code>
            amsmath
          </code>
        </indexterm>
      </cindex>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="860">
          <code>
            amsmath
          </code>
          <r>
            package
          </r>
        </indexterm>
      </cindex>
      <paraDefault handler: &latex;
>
         provides a variety of similar spacing commands for math mode (
        <pxref label="Spacing-in-math-mode">
          <xrefnodename>
            Spacing in math mode
          </xrefnodename>
        </pxref>
        ). With the
        <code>
          amsmath
        </code>
         package, or as of the 2020-10-01
Default handler: &latex;
         release, they can be used in text mode as well as math mode, including
        <code>
          \!
        </code>
         for
        <code>
          \negthinspace
        </code>
        ; but otherwise, they are available only in math mode.
      </para>
    </section>
    <node name="_005c_002f" spaces=" ">
      <nodename>
        \/
      </nodename>
      <nodenext automatic="on">
        \hrulefill
        &
         \dotfill
      </nodenext>
      <nodeprev automatic="on">
        \thinspace
        &
         \negthinspace
      </nodeprev>
      <nodeup automatic="on">
        Spaces
      </nodeup>
    </node>
    <section spaces=" ">
      <sectiontitle>
        <code>
          \/
        </code>
      </sectiontitle>
      <findex index="fn" spaces=" ">
        <indexterm index="fn" number="976" mergedindex="cp">
          \/
        </indexterm>
      </findex>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="861">
          italic correction
        </indexterm>
      </cindex>
      <para>
        Synopsis:
      </para>
      <example endspaces=" ">
        <pre xml:space="preserve">
          <var>
            before-character
          </var>
          \/
          <var>
            after-character
          </var>
        </pre>
      </example>
      <para>
        Insert an
        <dfn>
          italic correction
        </dfn>
        , a small space defined by the font designer for each character (possibly zero), to avoid the character colliding with whatever follows. When you use
        <code>
          \/
        </code>
        ,
Default handler: &latex;
         takes the correction from the font metric file, scales it by any scaling that has been applied to the font, and then inserts that much horizontal space.
      </para>
      <para>
        Here, were it not for the
        <code>
          \/
        </code>
        , the
        <var>
          before-character
        </var>
         italic
Default handler: &nbsp;
        f would hit the
        <var>
          after-character
        </var>
         roman
Default handler: &nbsp;
        H
      </para>
      <example endspaces=" ">
        <pre xml:space="preserve">
          \newcommand
Default handler: &lbrace;
          \companylogo
Default handler: &rbrace;
Default handler: &lbrace;
Default handler: &lbrace;
          \it f
Default handler: &rbrace;
          \/H
Default handler: &rbrace;
        </pre>
      </example>
      <noindent/>
      <para>
        because the italic letter f leans far to the right.
      </para>
      <para>
        If
        <var>
          after-character
        </var>
         is a period or comma then don
Default handler: &textrsquo;
        t insert an italic correction since those punctuation symbols are so low to the baseline already. However, with semicolons or colons, as well as with normal letters, the italic correction can help. It is typically used between a switch from italic or slanted fonts to an upright font.
      </para>
      <para>
        When you use commands such as
        <code>
          \emph
        </code>
         and
        <code>
          \textit
        </code>
         and
        <code>
          \textsl
        </code>
         to change fonts,
Default handler: &latex;
         automatically inserts the italic correction when needed (
        <pxref label="Font-styles">
          <xrefnodename>
            Font styles
          </xrefnodename>
        </pxref>
        ). However, declarations such as
        <code>
          \em
        </code>
         and
        <code>
          \itshape
        </code>
         and
        <code>
          \slshape
        </code>
         do not automatically insert italic corrections.
      </para>
      <para>
        Upright characters can also have an italic correction. An example where this is needed is the name
        <code>
          pdf\/\TeX
        </code>
        . However, most upright characters have a zero italic correction. Some font creators do not include italic correction values even for italic fonts.
      </para>
      <findex index="fn" spaces=" ">
        <indexterm index="fn" number="977" mergedindex="cp">
          \fontdimen1
        </indexterm>
      </findex>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="862">
          font dimension, slant
        </indexterm>
      </cindex>
      <para>
        Technically,
Default handler: &latex;
         uses another font-specific value, the so-called
        <dfn>
          slant parameter
        </dfn>
         (namely
        <code>
          \fontdimen1
        </code>
        ), to determine whether to possibly insert an italic correction, rather than tying the action to particular font commands.
      </para>
      <para>
        There is no concept of italic correction in math mode; math spacing is done in a different way.
      </para>
    </section>
    <node name="_005chrulefill-_0026-_005cdotfill" spaces=" ">
      <nodename>
        \hrulefill
        &
         \dotfill
      </nodename>
      <nodenext automatic="on">
        \bigskip
        &
         \medskip
        &
         \smallskip
      </nodenext>
      <nodeprev automatic="on">
        \/
      </nodeprev>
      <nodeup automatic="on">
        Spaces
      </nodeup>
    </node>
    <section spaces=" ">
      <sectiontitle>
        <code>
          \hrulefill
        </code>
        &
        <code>
          \dotfill
        </code>
      </sectiontitle>
      <anchor name="_005chrulefill">
        \hrulefill
      </anchor>
      <anchor name="_005cdotfill">
        \dotfill
      </anchor>
      <findex index="fn" spaces=" ">
        <indexterm index="fn" number="978" mergedindex="cp">
          \hrulefill
        </indexterm>
      </findex>
      <findex index="fn" spaces=" ">
        <indexterm index="fn" number="979" mergedindex="cp">
          \dotfill
        </indexterm>
      </findex>
      <para>
        Synopsis, one of:
      </para>
      <example endspaces=" ">
        <pre xml:space="preserve">
          \hrulefill \dotfill
        </pre>
      </example>
      <para>
        Produce an infinite horizontal rubber length (
        <pxref label="Lengths">
          <xrefnodename>
            Lengths
          </xrefnodename>
        </pxref>
        ) that
Default handler: &latex;
         fills with a rule (that is, a line) or with dots, instead of white space.
      </para>
      <para>
        This outputs a line 2 inches long.
      </para>
      <example endspaces=" ">
        <pre xml:space="preserve">
          Name:~\makebox[2in]
Default handler: &lbrace;
          \hrulefill
Default handler: &rbrace;
        </pre>
      </example>
      <noindent/>
      <para>
        This example, when placed between blank lines, creates a paragraph that is left and right justified and where the middle is filled with evenly spaced dots.
      </para>
      <example endspaces=" ">
        <pre xml:space="preserve">
          \noindent John Aubrey, RN \dotfill
Default handler: &lbrace;
Default handler: &rbrace;
           Melbury Lodge
        </pre>
      </example>
      <para>
        To make the rule or dots go to the line
Default handler: &textrsquo;
        s end use
        <code>
          \null
        </code>
         at the start or end.
      </para>
      <para>
        To change the rule
Default handler: &textrsquo;
        s thickness, copy the definition and adjust it, as here
      </para>
      <example endspaces=" ">
        <pre xml:space="preserve">
          \renewcommand
Default handler: &lbrace;
          \hrulefill
Default handler: &rbrace;
Default handler: &lbrace;
          % \leavevmode\leaders\hrule height 1pt\hfill\kern0pt
Default handler: &rbrace;
        </pre>
      </example>
      <noindent/>
      <para>
        which changes the default thickness of 0.4
        <dmn>
          pt
        </dmn>
         to 1
        <dmn>
          pt
        </dmn>
        . Similarly, adjust the dot spacing as with
      </para>
      <example endspaces=" ">
        <pre xml:space="preserve">
          \renewcommand
Default handler: &lbrace;
          \dotfill
Default handler: &rbrace;
Default handler: &lbrace;
          % \leavevmode\cleaders\hbox to 1.00em
Default handler: &lbrace;
          \hss .\hss
Default handler: &rbrace;
          \hfill\kern0pt
Default handler: &rbrace;
        </pre>
      </example>
      <noindent/>
      <para>
        which changes the default length of 0.33
        <dmn>
          em
        </dmn>
         to 1.00
        <dmn>
          em
        </dmn>
        .
      </para>
      <para>
        This example produces a line for a signature.
      </para>
      <example endspaces=" ">
        <pre xml:space="preserve">
          \begin
Default handler: &lbrace;
          minipage
Default handler: &rbrace;
Default handler: &lbrace;
          4cm
Default handler: &rbrace;
           \centering \hrulefill\\ Signed \end
Default handler: &lbrace;
          minipage
Default handler: &rbrace;
        </pre>
      </example>
      <noindent/>
      <para>
        The line is 4
        <dmn>
          cm
        </dmn>
         long.
      </para>
    </section>
    <node name="_005cbigskip-_0026-_005cmedskip-_0026-_005csmallskip" spaces=" ">
      <nodename>
        \bigskip
        &
         \medskip
        &
         \smallskip
      </nodename>
      <nodenext automatic="on">
        \bigbreak
        &
         \medbreak
        &
         \smallbreak
      </nodenext>
      <nodeprev automatic="on">
        \hrulefill
        &
         \dotfill
      </nodeprev>
      <nodeup automatic="on">
        Spaces
      </nodeup>
    </node>
    <section spaces=" ">
      <sectiontitle>
        <code>
          \bigskip
        </code>
        &
        <code>
          \medskip
        </code>
        &
        <code>
          \smallskip
        </code>
      </sectiontitle>
      <anchor name="_005cbigskip">
        \bigskip
      </anchor>
      <anchor name="_005cmedskip">
        \medskip
      </anchor>
      <anchor name="_005csmallskip">
        \smallskip
      </anchor>
      <findex index="fn" spaces=" ">
        <indexterm index="fn" number="980" mergedindex="cp">
          \bigskip
        </indexterm>
      </findex>
      <findex index="fn" spaces=" ">
        <indexterm index="fn" number="981" mergedindex="cp">
          \medskip
        </indexterm>
      </findex>
      <findex index="fn" spaces=" ">
        <indexterm index="fn" number="982" mergedindex="cp">
          \smallskip
        </indexterm>
      </findex>
      <para>
        Synopsis, one of:
      </para>
      <example endspaces=" ">
        <pre xml:space="preserve">
          \bigskip \medskip \smallskip
        </pre>
      </example>
      <para>
        Produce an amount of vertical space, large or medium-sized or small. These commands are fragile (
        <pxref label="_005cprotect">
          <xrefnodename>
            \protect
          </xrefnodename>
        </pxref>
        ).
      </para>
      <para>
        Here the skip suggests the passage of time (from
        <i>
          The Golden Ocean
        </i>
         by O
Default handler: &textrsquo;
        Brian).
      </para>
      <example endspaces=" ">
        <pre xml:space="preserve">
          Mr Saumarez would have something rude to say to him, no doubt: he was at home again, and it was delightful. \bigskip ``A hundred and fifty-seven miles and one third, in twenty-four hours,'' said Peter.
        </pre>
      </example>
      <para>
        Each command is associated with a length defined in the document class file.
      </para>
      <ftable commandarg="code" spaces=" " endspaces=" ">
        <beforefirstitem>
          <anchor name="bigskip">
            bigskip
          </anchor>
        </beforefirstitem>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                <indexterm index="fn" number="983" mergedindex="cp">
                  \bigskip
                </indexterm>
                \bigskip
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <findex index="fn" spaces=" ">
              <indexterm index="fn" number="984" mergedindex="cp">
                \bigskipamount
              </indexterm>
            </findex>
            <para>
              The same as
              <code>
                \vspace
Default handler: &lbrace;
                \bigskipamount
Default handler: &rbrace;
              </code>
              , ordinarily about one line space, with stretch and shrink. The default for the
              <code>
                book
              </code>
               and
              <code>
                article
              </code>
               classes is
              <code>
                12pt plus 4pt minus 4pt
              </code>
              .
            </para>
            <anchor name="medskip">
              medskip
            </anchor>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                <indexterm index="fn" number="985" mergedindex="cp">
                  \medskip
                </indexterm>
                \medskip
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <findex index="fn" spaces=" ">
              <indexterm index="fn" number="986" mergedindex="cp">
                \medskipamount
              </indexterm>
            </findex>
            <para>
              The same as
              <code>
                \vspace
Default handler: &lbrace;
                \medskipamount
Default handler: &rbrace;
              </code>
              , ordinarily about half of a line space, with stretch and shrink. The default for the
              <code>
                book
              </code>
               and
              <code>
                article
              </code>
               classes is
              <code>
                6pt plus 2pt minus 2pt
              </code>
              .
            </para>
            <anchor name="smallskip">
              smallskip
            </anchor>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                <indexterm index="fn" number="987" mergedindex="cp">
                  \smallskip
                </indexterm>
                \smallskip
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <findex index="fn" spaces=" ">
              <indexterm index="fn" number="988" mergedindex="cp">
                \smallskipamount
              </indexterm>
            </findex>
            <para>
              The same as
              <code>
                \vspace
Default handler: &lbrace;
                \smallskipamount
Default handler: &rbrace;
              </code>
              , ordinarily about a quarter of a line space, with stretch and shrink. The default for the
              <code>
                book
              </code>
               and
              <code>
                article
              </code>
               classes is
              <code>
                3pt plus 1pt minus 1pt
              </code>
              .
            </para>
          </tableitem>
        </tableentry>
      </ftable>
      <para>
        Because each command is a
        <code>
          \vspace
        </code>
        , if you use it in mid-paragraph then it will insert its vertical space between the line in which you use it and the next line, not necessarily at the place that you use it. So these are best between paragraphs.
      </para>
      <para>
        The commands
        <code>
          \bigbreak
        </code>
        ,
        <code>
          \medbreak
        </code>
        , and
        <code>
          \smallbreak
        </code>
         are similar but also suggest to
Default handler: &latex;
         that this is a good place to put a page break (
        <pxref label="_005cbigbreak-_0026-_005cmedbreak-_0026-_005csmallbreak">
          <xrefnodename>
            \bigbreak
            &
             \medbreak
            &
             \smallbreak
          </xrefnodename>
        </pxref>
        .
      </para>
    </section>
    <node name="_005cbigbreak-_0026-_005cmedbreak-_0026-_005csmallbreak" spaces=" ">
      <nodename>
        \bigbreak
        &
         \medbreak
        &
         \smallbreak
      </nodename>
      <nodenext automatic="on">
        \strut
      </nodenext>
      <nodeprev automatic="on">
        \bigskip
        &
         \medskip
        &
         \smallskip
      </nodeprev>
      <nodeup automatic="on">
        Spaces
      </nodeup>
    </node>
    <section spaces=" ">
      <sectiontitle>
        <code>
          \bigbreak
        </code>
        &
        <code>
          \medbreak
        </code>
        &
        <code>
          \smallbreak
        </code>
      </sectiontitle>
      <anchor name="_005cbigbreak">
        \bigbreak
      </anchor>
      <anchor name="_005cmedbreak">
        \medbreak
      </anchor>
      <anchor name="_005csmallbreak">
        \smallbreak
      </anchor>
      <findex index="fn" spaces=" ">
        <indexterm index="fn" number="989" mergedindex="cp">
          \bigbreak
        </indexterm>
      </findex>
      <findex index="fn" spaces=" ">
        <indexterm index="fn" number="990" mergedindex="cp">
          \medbreak
        </indexterm>
      </findex>
      <findex index="fn" spaces=" ">
        <indexterm index="fn" number="991" mergedindex="cp">
          \smallbreak
        </indexterm>
      </findex>
      <para>
        Synopsis, one of:
      </para>
      <example endspaces=" ">
        <pre xml:space="preserve">
          \bigbreak \medbreak \smallbreak
        </pre>
      </example>
      <para>
        Produce a vertical space that is big or medium-sized or small, and suggest to
Default handler: &latex;
         that this is a good place to break the page. (The associated penalties are respectively
Default handler: &minus;
        200,
Default handler: &minus;
        100, and
Default handler: &minus;
        50.)
      </para>
      <para>
        <xref label="_005cbigskip-_0026-_005cmedskip-_0026-_005csmallskip">
          <xrefnodename>
            \bigskip
            &
             \medskip
            &
             \smallskip
          </xrefnodename>
        </xref>
        , for more. These commands produce the same vertical space but differ in that they also remove a preceding vertical space if it is less than what they would insert (as with
        <code>
          \addvspace
        </code>
        ). In addition, they terminate a paragraph where they are used: this example
      </para>
      <example endspaces=" ">
        <pre xml:space="preserve">
          abc\bigbreak def ghi jkl mno pqr
        </pre>
      </example>
      <noindent/>
      <para>
        will output three paragraphs, the first ending in
        <samp>
          abc
        </samp>
         and the second starting, after an extra vertical space and a paragraph indent, with
        <samp>
          def
        </samp>
        .
      </para>
    </section>
    <node name="_005cstrut" spaces=" ">
      <nodename>
        \strut
      </nodename>
      <nodenext automatic="on">
        \vspace
      </nodenext>
      <nodeprev automatic="on">
        \bigbreak
        &
         \medbreak
        &
         \smallbreak
      </nodeprev>
      <nodeup automatic="on">
        Spaces
      </nodeup>
    </node>
    <section spaces=" ">
      <sectiontitle>
        <code>
          \strut
        </code>
      </sectiontitle>
      <findex index="fn" spaces=" ">
        <indexterm index="fn" number="992" mergedindex="cp">
          \strut
        </indexterm>
      </findex>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="863">
          strut
        </indexterm>
      </cindex>
      <para>
        Synopsis:
      </para>
      <example endspaces=" ">
        <pre xml:space="preserve">
          \strut
        </pre>
      </example>
      <para>
        Ensure that the current line has height at least
        <code>
          0.7\baselineskip
        </code>
         and depth at least
        <code>
          0.3\baselineskip
        </code>
        . Essentially,
Default handler: &latex;
         inserts into the line a rectangle having zero width,
        <code>
          \rule[-0.3\baselineskip]
Default handler: &lbrace;
          0pt
Default handler: &rbrace;
Default handler: &lbrace;
          \baselineskip
Default handler: &rbrace;
        </code>
         (
        <pxref label="_005crule">
          <xrefnodename>
            \rule
          </xrefnodename>
        </pxref>
        ). The
        <code>
          \baselineskip
        </code>
         changes with the current font or fontsize.
      </para>
      <para>
        In this example the
        <code>
          \strut
        </code>
         keeps the box inside the frame from having zero height.
      </para>
      <example endspaces=" ">
        <pre xml:space="preserve">
          \setlength
Default handler: &lbrace;
          \fboxsep
Default handler: &rbrace;
Default handler: &lbrace;
          0pt
Default handler: &rbrace;
          \framebox[2in]
Default handler: &lbrace;
          \strut
Default handler: &rbrace;
        </pre>
      </example>
      <para>
        This example has four lists. In the first there is a much bigger gap between items 2 and
Default handler: &nbsp;
        3 than there is between items 1 and
Default handler: &nbsp;
        2. The second list fixes that with a
        <code>
          \strut
        </code>
         at the end of its first item
Default handler: &textrsquo;
        s second line.
      </para>
      <example endspaces=" ">
        <pre xml:space="preserve">
          \setlength
Default handler: &lbrace;
          \fboxsep
Default handler: &rbrace;
Default handler: &lbrace;
          0pt
Default handler: &rbrace;
           \noindent\begin
Default handler: &lbrace;
          minipage
Default handler: &rbrace;
          [t]
Default handler: &lbrace;
          0.2\linewidth
Default handler: &rbrace;
           \begin
Default handler: &lbrace;
          enumerate
Default handler: &rbrace;
           \item \parbox[t]
Default handler: &lbrace;
          15pt
Default handler: &rbrace;
Default handler: &lbrace;
          test \\ test
Default handler: &rbrace;
           \item test \item test \end
Default handler: &lbrace;
          enumerate
Default handler: &rbrace;
           \end
Default handler: &lbrace;
          minipage
Default handler: &rbrace;
          % \begin
Default handler: &lbrace;
          minipage
Default handler: &rbrace;
          [t]
Default handler: &lbrace;
          0.2\linewidth
Default handler: &rbrace;
           \begin
Default handler: &lbrace;
          enumerate
Default handler: &rbrace;
           \item \parbox[t]
Default handler: &lbrace;
          15pt
Default handler: &rbrace;
Default handler: &lbrace;
          test \\ test\strut
Default handler: &rbrace;
           \item test \item test \end
Default handler: &lbrace;
          enumerate
Default handler: &rbrace;
           \end
Default handler: &lbrace;
          minipage
Default handler: &rbrace;
          % \begin
Default handler: &lbrace;
          minipage
Default handler: &rbrace;
          [t]
Default handler: &lbrace;
          0.2\linewidth
Default handler: &rbrace;
           \begin
Default handler: &lbrace;
          enumerate
Default handler: &rbrace;
           \item \fbox
Default handler: &lbrace;
          \parbox[t]
Default handler: &lbrace;
          15pt
Default handler: &rbrace;
Default handler: &lbrace;
          test \\ test
Default handler: &rbrace;
Default handler: &rbrace;
           \item \fbox
Default handler: &lbrace;
          test
Default handler: &rbrace;
           \item \fbox
Default handler: &lbrace;
          test
Default handler: &rbrace;
           \end
Default handler: &lbrace;
          enumerate
Default handler: &rbrace;
           \end
Default handler: &lbrace;
          minipage
Default handler: &rbrace;
          % \begin
Default handler: &lbrace;
          minipage
Default handler: &rbrace;
          [t]
Default handler: &lbrace;
          0.2\linewidth
Default handler: &rbrace;
           \begin
Default handler: &lbrace;
          enumerate
Default handler: &rbrace;
           \item \fbox
Default handler: &lbrace;
          \parbox[t]
Default handler: &lbrace;
          15pt
Default handler: &rbrace;
Default handler: &lbrace;
          test \\ test\strut
Default handler: &rbrace;
Default handler: &rbrace;
           \item \fbox
Default handler: &lbrace;
          test
Default handler: &rbrace;
           \item \fbox
Default handler: &lbrace;
          test
Default handler: &rbrace;
           \end
Default handler: &lbrace;
          enumerate
Default handler: &rbrace;
           \end
Default handler: &lbrace;
          minipage
Default handler: &rbrace;
          %
        </pre>
      </example>
      <noindent/>
      <para>
        The final two lists use
        <code>
          \fbox
        </code>
         to show what
Default handler: &textrsquo;
        s happening. The first item
        <code>
          \parbox
        </code>
         of the third list goes only to the bottom of its second
        <samp>
          test
        </samp>
        , which happens not have any characters that descend below the baseline. The fourth list adds the strut that gives the needed extra below-baseline space.
      </para>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="864">
          <r>
            package
          </r>
          ,
          <code>
            TikZ
          </code>
        </indexterm>
      </cindex>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="865">
          <code>
            TikZ
          </code>
          <r>
            package
          </r>
        </indexterm>
      </cindex>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="866">
          <r>
            package
          </r>
          ,
          <code>
            Asymptote
          </code>
        </indexterm>
      </cindex>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="867">
          <code>
            Asymptote
          </code>
          <r>
            package
          </r>
        </indexterm>
      </cindex>
      <para>
        The
        <code>
          \strut
        </code>
         command is often useful in graphics, such as in
        <code>
          TikZ
        </code>
         or
        <code>
          Asymptote
        </code>
        . For instance, you may have a command such as
        <code>
          \graphnode
Default handler: &lbrace;
          <var>
            node-name
          </var>
Default handler: &rbrace;
        </code>
         that fits a circle around
        <var>
          node-name
        </var>
        . However, unless you are careful the
        <var>
          node-name
        </var>
Default handler: &textrsquo;
        s
        <samp>
          x
        </samp>
         and
        <samp>
          y
        </samp>
         will produce different-diameter circles because the characters are different sizes. A careful
        <code>
          \graphnode
        </code>
         might insert a
        <code>
          \strut
        </code>
        , then
        <var>
          node-name
        </var>
        , and then draw the circle.
      </para>
      <para>
        The general approach of using a zero width
        <code>
          \rule
        </code>
         is useful in many circumstances. In this table, the zero-width rule keeps the top of the first integral from hitting the
        <code>
          \hline
        </code>
        . Similarly, the second rule keeps the second integral from hitting the first.
      </para>
      <example endspaces=" ">
        <pre xml:space="preserve">
          \begin
Default handler: &lbrace;
          tabular
Default handler: &rbrace;
Default handler: &lbrace;
          rl
Default handler: &rbrace;
           \textsc
Default handler: &lbrace;
          Integral
Default handler: &rbrace;
          &
          \textsc
Default handler: &lbrace;
          Value
Default handler: &rbrace;
           \\ \hline $\int_0^x t\, dt$
          &
          $x^2/2$ \rule
Default handler: &lbrace;
          0em
Default handler: &rbrace;
Default handler: &lbrace;
          2.5ex
Default handler: &rbrace;
           \\ $\int_0^x t^2\, dt$
          &
          $x^3/3$ \rule
Default handler: &lbrace;
          0em
Default handler: &rbrace;
Default handler: &lbrace;
          2.5ex
Default handler: &rbrace;
           \end
Default handler: &lbrace;
          tabular
Default handler: &rbrace;
        </pre>
      </example>
      <noindent/>
      <para>
        (Although the line-ending double backslash command has an available optional argument to change the corresponding baseline skip, that won
Default handler: &textrsquo;
        t solve this issue. Changing the first double backslash to something like
        <code>
          \\[2.5ex]
        </code>
         will put more room between the header line and the
        <code>
          \hline
        </code>
         rule, and the integral would still hit the rule.)
      </para>
    </section>
    <node name="_005cvspace" spaces=" ">
      <nodename>
        \vspace
      </nodename>
      <nodenext automatic="on">
        \vfill
      </nodenext>
      <nodeprev automatic="on">
        \strut
      </nodeprev>
      <nodeup automatic="on">
        Spaces
      </nodeup>
    </node>
    <section spaces=" ">
      <sectiontitle>
        <code>
          \vspace
        </code>
      </sectiontitle>
      <findex index="fn" spaces=" ">
        <indexterm index="fn" number="993" mergedindex="cp">
          \vspace
        </indexterm>
      </findex>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="868">
          vertical space
        </indexterm>
      </cindex>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="869">
          space, vertical
        </indexterm>
      </cindex>
      <para>
        Synopsis, one of:
      </para>
      <example endspaces=" ">
        <pre xml:space="preserve">
          \vspace
Default handler: &lbrace;
          <var>
            length
          </var>
Default handler: &rbrace;
           \vspace*
Default handler: &lbrace;
          <var>
            length
          </var>
Default handler: &rbrace;
        </pre>
      </example>
      <para>
        Add the vertical space
        <var>
          length
        </var>
        . The
        <var>
          length
        </var>
         can be positive, negative, or zero. It is a rubber length
Default handler: &textmdash;
        it may contain a
        <code>
          plus
        </code>
         or
        <code>
          minus
        </code>
         component (
        <pxref label="Lengths">
          <xrefnodename>
            Lengths
          </xrefnodename>
        </pxref>
        ).
      </para>
      <para>
        This puts space between the two paragraphs.
      </para>
      <example endspaces=" ">
        <pre xml:space="preserve">
          And I slept. \vspace
Default handler: &lbrace;
          1ex plus 0.5ex
Default handler: &rbrace;
           The new day dawned cold.
        </pre>
      </example>
      <noindent/>
      <para>
        (
        <xref label="_005cbigskip-_0026-_005cmedskip-_0026-_005csmallskip">
          <xrefnodename>
            \bigskip
            &
             \medskip
            &
             \smallskip
          </xrefnodename>
        </xref>
        , for common inter-paragraph spaces.)
      </para>
      <para>
        The
        <code>
          *
        </code>
        -form inserts vertical space that is non-discardable. More precisely,
Default handler: &latex;
         discards vertical space at a page break and the
        <code>
          *
        </code>
        -form causes the space to stay. This example leaves space between the two questions.
      </para>
      <example endspaces=" ">
        <pre xml:space="preserve">
          Question: Find the integral of \( 5x^4+5 \). \vspace*
Default handler: &lbrace;
          2cm plus 0.5cm
Default handler: &rbrace;
           Question: Find the derivative of \( x^5+5x+9 \).
        </pre>
      </example>
      <noindent/>
      <para>
        That space will be present even if the page break happens to fall between the questions.
      </para>
      <para>
        If you use
        <code>
          \vspace
        </code>
         in the middle of a paragraph (i.e., in horizontal mode) then the space is inserted after the line containing the
        <code>
          \vspace
        </code>
         command; it does not start a new paragraph at the
        <code>
          \vspace
        </code>
         command.
      </para>
      <para>
        In this example the two questions will be evenly spaced vertically on the page, with at least one inch of space below each.
      </para>
      <example endspaces=" ">
        <pre xml:space="preserve">
          \begin
Default handler: &lbrace;
          document
Default handler: &rbrace;
           1) Who put the bomp in the bomp bah bomp bah bomp? \vspace
Default handler: &lbrace;
          1in plus 1fill
Default handler: &rbrace;
           2) Who put the ram in the rama lama ding dong? \vspace
Default handler: &lbrace;
          1in plus 1fill
Default handler: &rbrace;
           \end
Default handler: &lbrace;
          document
Default handler: &rbrace;
        </pre>
      </example>
    </section>
    <node name="_005cvfill" spaces=" ">
      <nodename>
        \vfill
      </nodename>
      <nodenext automatic="on">
        \addvspace
      </nodenext>
      <nodeprev automatic="on">
        \vspace
      </nodeprev>
      <nodeup automatic="on">
        Spaces
      </nodeup>
    </node>
    <section spaces=" ">
      <sectiontitle>
        <code>
          \vfill
        </code>
      </sectiontitle>
      <findex index="fn" spaces=" ">
        <indexterm index="fn" number="994" mergedindex="cp">
          \vfill
        </indexterm>
      </findex>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="870">
          stretch, infinite vertical
        </indexterm>
      </cindex>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="871">
          infinite vertical stretch
        </indexterm>
      </cindex>
      <para>
        Synopsis:
      </para>
      <example endspaces=" ">
        <pre xml:space="preserve">
          \vfill
        </pre>
      </example>
      <para>
        End the current paragraph and insert a vertical rubber length that is infinite, so it can stretch or shrink as far as needed (
        <pxref label="Lengths">
          <xrefnodename>
            Lengths
          </xrefnodename>
        </pxref>
        ).
      </para>
      <para>
        It is often used in the same way as
        <code>
          \vspace
Default handler: &lbrace;
          \fill
Default handler: &rbrace;
        </code>
        , except that
        <code>
          \vfill
        </code>
         ends the current paragraph whereas
        <code>
          \vspace
Default handler: &lbrace;
          \fill
Default handler: &rbrace;
        </code>
         adds the infinite vertical space below its line, irrespective of the paragraph structure. In both cases that space will disappear at a page boundary; to circumvent this see the starred option in
Default handler: &nbsp;
        <ref label="_005cvspace">
          <xrefnodename>
            \vspace
          </xrefnodename>
        </ref>
        .
      </para>
      <para>
        In this example the page is filled, so the top and bottom lines contain the text
        <samp>
          Lost Dog!
        </samp>
         and the second
        <samp>
          Lost Dog!
        </samp>
         is exactly halfway between them.
      </para>
      <example endspaces=" ">
        <pre xml:space="preserve">
          \begin
Default handler: &lbrace;
          document
Default handler: &rbrace;
           Lost Dog! \vfill Lost Dog! % perfectly in the middle \vfill Lost Dog! \end
Default handler: &lbrace;
          document
Default handler: &rbrace;
        </pre>
      </example>
    </section>
    <node name="_005caddvspace" spaces=" ">
      <nodename>
        \addvspace
      </nodename>
      <nodeprev automatic="on">
        \vfill
      </nodeprev>
      <nodeup automatic="on">
        Spaces
      </nodeup>
    </node>
    <section spaces=" ">
      <sectiontitle>
        <code>
          \addvspace
        </code>
      </sectiontitle>
      <findex index="fn" spaces=" ">
        <indexterm index="fn" number="995" mergedindex="cp">
          \addvspace
        </indexterm>
      </findex>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="872">
          vertical space
        </indexterm>
      </cindex>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="873">
          space, inserting vertical
        </indexterm>
      </cindex>
      <para>
        Synopsis:
      </para>
      <example endspaces=" ">
        <pre xml:space="preserve">
          \addvspace
Default handler: &lbrace;
          <var>
            vert-length
          </var>
Default handler: &rbrace;
        </pre>
      </example>
      <para>
        Add a vertical space of
        <var>
          vert-length
        </var>
        . However, if there are two or more
        <code>
          \addvspace
        </code>
Default handler: &textrsquo;
        s in a sequence then together they only add the space needed to make the natural length equal to the maximum of the
        <var>
          vert-length
        </var>
Default handler: &textrsquo;
        s in that sequence. This command is fragile (
        <pxref label="_005cprotect">
          <xrefnodename>
            \protect
          </xrefnodename>
        </pxref>
        ). The
        <var>
          vert-length
        </var>
         is a rubber length (
        <pxref label="Lengths">
          <xrefnodename>
            Lengths
          </xrefnodename>
        </pxref>
        ).
      </para>
      <para>
        This example illustrates. The
        <code>
          picture
        </code>
         draws a scale over which to rules are placed. In a standard
Default handler: &latex;
         article the length
        <code>
          \baselineskip
        </code>
         is 12
        <dmn>
          pt
        </dmn>
        . As shown by the scale, the two rules are 22
        <dmn>
          pt
        </dmn>
         apart: the sum of the
        <code>
          \baselineskip
        </code>
         and the 10
        <dmn>
          pt
        </dmn>
         from the first
        <code>
          \addvspace
        </code>
        .
      </para>
      <example endspaces=" ">
        <pre xml:space="preserve">
          \documentclass
Default handler: &lbrace;
          article
Default handler: &rbrace;
           \usepackage
Default handler: &lbrace;
          color
Default handler: &rbrace;
           \begin
Default handler: &lbrace;
          document
Default handler: &rbrace;
           \setlength
Default handler: &lbrace;
          \unitlength
Default handler: &rbrace;
Default handler: &lbrace;
          2pt
Default handler: &rbrace;
          % \noindent\begin
Default handler: &lbrace;
          picture
Default handler: &rbrace;
          (0,0)% \multiput(0,0)(0,-1)
Default handler: &lbrace;
          25
Default handler: &rbrace;
Default handler: &lbrace;
Default handler: &lbrace;
          \color
Default handler: &lbrace;
          blue
Default handler: &rbrace;
          \line(1,0)
Default handler: &lbrace;
          1
Default handler: &rbrace;
Default handler: &rbrace;
Default handler: &rbrace;
           \multiput(0,0)(0,-5)
Default handler: &lbrace;
          6
Default handler: &rbrace;
Default handler: &lbrace;
Default handler: &lbrace;
          \color
Default handler: &lbrace;
          red
Default handler: &rbrace;
          \line(1,0)
Default handler: &lbrace;
          2
Default handler: &rbrace;
Default handler: &rbrace;
Default handler: &rbrace;
           \end
Default handler: &lbrace;
          picture
Default handler: &rbrace;
          % \rule
Default handler: &lbrace;
          0.25\linewidth
Default handler: &rbrace;
Default handler: &lbrace;
          0.1pt
Default handler: &rbrace;
          % \par\addvspace
Default handler: &lbrace;
          10pt
Default handler: &rbrace;
          % \addvspace
Default handler: &lbrace;
          20pt
Default handler: &rbrace;
          % \par\noindent\rule
Default handler: &lbrace;
          0.25\linewidth
Default handler: &rbrace;
Default handler: &lbrace;
          0.1pt
Default handler: &rbrace;
          % \end
Default handler: &lbrace;
          document
Default handler: &rbrace;
        </pre>
      </example>
      <noindent/>
      <para>
        Now uncomment the second
        <code>
          \addvspace
        </code>
        . It does not make the gap 20
        <dmn>
          pt
        </dmn>
         longer; instead the gap is the sum of
        <code>
          \baselineskip
        </code>
         and 20
        <dmn>
          pt
        </dmn>
        . So
        <code>
          \addvspace
        </code>
         in a sense does the opposite of its name
Default handler: &textmdash;
        it makes sure that multiple vertical spaces do not accumulate, but instead that only the largest one is used.
      </para>
      <paraDefault handler: &latex;
>
         uses this command to adjust the vertical space above or below an environment that starts a new paragraph. For instance, a
        <code>
          theorem
        </code>
         environment begins and ends with
        <code>
          \addvspace
        </code>
         so that two consecutive
        <code>
          theorem
        </code>
Default handler: &textrsquo;
        s are separated by one vertical space, not two.
      </para>
      <para>
        A error
        <samp>
          Something's wrong--perhaps a missing \item
        </samp>
         pointing to an
        <code>
          \addvspace
        </code>
         means that you were not in vertical mode when you hit this command. One way to change that is to precede
        <code>
          \addvspace
        </code>
         with a
        <code>
          \par
        </code>
         command (
        <pxref label="_005cpar">
          <xrefnodename>
            \par
          </xrefnodename>
        </pxref>
        ), as in the above example.
      </para>
    </section>
  </chapter>
  <node name="Boxes" spaces=" ">
    <nodename>
      Boxes
    </nodename>
    <nodenext automatic="on">
      Graphics
    </nodenext>
    <nodeprev automatic="on">
      Spaces
    </nodeprev>
    <nodeup automatic="on">
      Top
    </nodeup>
  </node>
  <chapter spaces=" ">
    <sectiontitle>
      Boxes
    </sectiontitle>
    <cindex index="cp" spaces=" ">
      <indexterm index="cp" number="874">
        boxes
      </indexterm>
    </cindex>
Default handler: <!-- c xx Expand on boxes and glue, for xref from elsewhere. -->
    <para>
      At its core,
Default handler: &latex;
       puts things in boxes and then puts the boxes on a page. So these commands are central.
    </para>
    <cindex index="cp" spaces=" ">
      <indexterm index="cp" number="875">
        <r>
          package
        </r>
        ,
        <code>
          adjustbox
        </code>
      </indexterm>
    </cindex>
    <cindex index="cp" spaces=" ">
      <indexterm index="cp" number="876">
        <code>
          adjustbox
        </code>
        <r>
          package
        </r>
      </indexterm>
    </cindex>
    <para>
      There are many packages on CTAN that are useful for manipulating boxes. One useful adjunct to the commands here is
      <code>
        adjustbox
      </code>
      .
    </para>
    <menu endspaces=" ">
      <menuentry>
        <menuleadingtext>
          *
        </menuleadingtext>
        <menunode>
          \mbox
          &
           \makebox
        </menunode>
        <menuseparator>
          ::
        </menuseparator>
        <menudescription>
          <pre xml:space="preserve">
            Horizontal boxes.
          </pre>
        </menudescription>
      </menuentry>
      <menuentry>
        <menuleadingtext>
          *
        </menuleadingtext>
        <menunode>
          \fbox
          &
           \framebox
        </menunode>
        <menuseparator>
          ::
        </menuseparator>
        <menudescription>
          <pre xml:space="preserve">
            Put a frame around a box.
          </pre>
        </menudescription>
      </menuentry>
      <menuentry>
        <menuleadingtext>
          *
        </menuleadingtext>
        <menunode>
          \parbox
        </menunode>
        <menuseparator>
          ::
        </menuseparator>
        <menudescription>
          <pre xml:space="preserve">
            Box with text in paragraph mode.
          </pre>
        </menudescription>
      </menuentry>
      <menuentry>
        <menuleadingtext>
          *
        </menuleadingtext>
        <menunode>
          \raisebox
        </menunode>
        <menuseparator>
          ::
        </menuseparator>
        <menudescription>
          <pre xml:space="preserve">
            Raise or lower text.
          </pre>
        </menudescription>
      </menuentry>
      <menuentry>
        <menuleadingtext>
          *
        </menuleadingtext>
        <menunode>
          \sbox
          &
           \savebox
        </menunode>
        <menuseparator>
          ::
        </menuseparator>
        <menudescription>
          <pre xml:space="preserve">
            Like
            <code>
              \makebox
            </code>
             but save the text for later.
          </pre>
        </menudescription>
      </menuentry>
      <menuentry>
        <menuleadingtext>
          *
        </menuleadingtext>
        <menunode>
          lrbox
        </menunode>
        <menuseparator>
          ::
        </menuseparator>
        <menudescription>
          <pre xml:space="preserve">
            Environment version of
            <code>
              \sbox
            </code>
            .
          </pre>
        </menudescription>
      </menuentry>
      <menuentry>
        <menuleadingtext>
          *
        </menuleadingtext>
        <menunode>
          \usebox
        </menunode>
        <menuseparator>
          ::
        </menuseparator>
        <menudescription>
          <pre xml:space="preserve">
            Print saved text.
          </pre>
        </menudescription>
      </menuentry>
    </menu>
    <node name="_005cmbox-_0026-_005cmakebox" spaces=" ">
      <nodename>
        \mbox
        &
         \makebox
      </nodename>
      <nodenext automatic="on">
        \fbox
        &
         \framebox
      </nodenext>
      <nodeup automatic="on">
        Boxes
      </nodeup>
    </node>
    <section spaces=" ">
      <sectiontitle>
        <code>
          \mbox
        </code>
        &
        <code>
          \makebox
        </code>
      </sectiontitle>
      <anchor name="_005cmbox">
        \mbox
      </anchor>
      <anchor name="_005cmakebox">
        \makebox
      </anchor>
      <findex index="fn" spaces=" ">
        <indexterm index="fn" number="996" mergedindex="cp">
          \mbox
        </indexterm>
      </findex>
      <findex index="fn" spaces=" ">
        <indexterm index="fn" number="997" mergedindex="cp">
          \makebox
        </indexterm>
      </findex>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="877">
          box
        </indexterm>
      </cindex>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="878">
          make a box
        </indexterm>
      </cindex>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="879">
          hyphenation, preventing
        </indexterm>
      </cindex>
      <para>
        Synopsis, one of:
      </para>
      <example endspaces=" ">
        <pre xml:space="preserve">
          \mbox
Default handler: &lbrace;
          <var>
            text
          </var>
Default handler: &rbrace;
           \makebox
Default handler: &lbrace;
          <var>
            text
          </var>
Default handler: &rbrace;
           \makebox[
          <var>
            width
          </var>
          ]
Default handler: &lbrace;
          <var>
            text
          </var>
Default handler: &rbrace;
           \makebox[
          <var>
            width
          </var>
          ][
          <var>
            position
          </var>
          ]
Default handler: &lbrace;
          <var>
            text
          </var>
Default handler: &rbrace;
        </pre>
      </example>
      <para>
        Create a box, a container for material. The
        <var>
          text
        </var>
         is typeset in LR mode (
        <pxref label="Modes">
          <xrefnodename>
            Modes
          </xrefnodename>
        </pxref>
        ) so it is not broken into lines. The
        <code>
          \mbox
        </code>
         command is robust, while
        <code>
          \makebox
        </code>
         is fragile (
        <pxref label="_005cprotect">
          <xrefnodename>
            \protect
          </xrefnodename>
        </pxref>
        ).
      </para>
      <para>
        Because
        <code>
          text
        </code>
         is not broken into lines, you can use
        <code>
          \mbox
        </code>
         to prevent hyphenation. In this example,
Default handler: &latex;
         will not hyphenate the tank name,
        <samp>
          T-34
        </samp>
        .
      </para>
      <example endspaces=" ">
        <pre xml:space="preserve">
          The soviet tank \mbox
Default handler: &lbrace;
          T-34
Default handler: &rbrace;
           is a symbol of victory against nazism.
        </pre>
      </example>
      <para>
        The first two command invocations shown,
        <code>
          \mbox
        </code>
         and
        <code>
          \makebox
        </code>
        , are roughly the same. They create a box just wide enough to contain the
        <var>
          text
        </var>
        . (They are like plain
Default handler: &tex;
Default handler: &textrsquo;
        s
        <code>
          \hbox
        </code>
        .)
      </para>
      <para>
        In the third version the optional argument
        <var>
          width
        </var>
         specifies the width of the box. Note that the space occupied by the text need not equal the width of the box. For one thing,
        <var>
          text
        </var>
         can be too small; this creates a full-line box:
      </para>
      <example endspaces=" ">
        <pre xml:space="preserve">
          \makebox[\linewidth]
Default handler: &lbrace;
          Chapter Exam
Default handler: &rbrace;
        </pre>
      </example>
      <noindent/>
      <para>
        with
        <samp>
          Chapter Exam
        </samp>
         centered. But
        <var>
          text
        </var>
         can also be too wide for
        <var>
          width
        </var>
        . See the example below of zero-width boxes.
      </para>
      <anchor name="mbox-makebox-depth">
        mbox makebox depth
      </anchor>
      <anchor name="mbox-makebox-height">
        mbox makebox height
      </anchor>
      <anchor name="mbox-makebox-width">
        mbox makebox width
      </anchor>
      <anchor name="mbox-makebox-totalheight">
        mbox makebox totalheight
      </anchor>
      <para>
        In the
        <var>
          width
        </var>
         argument you can use the following lengths that refer to the dimension of the box that
Default handler: &latex;
         gets on typesetting
        <var>
          text
        </var>
        :
        <code>
          \depth
        </code>
        ,
        <code>
          \height
        </code>
        ,
        <code>
          \width
        </code>
        ,
        <code>
          \totalheight
        </code>
         (this is the box
Default handler: &textrsquo;
        s height plus its depth). For example, to make a box with the text stretched to double the natural size you can say this.
      </para>
      <example endspaces=" ">
        <pre xml:space="preserve">
          \makebox[2\width]
Default handler: &lbrace;
          Get a stretcher
Default handler: &rbrace;
        </pre>
      </example>
      <para>
        For the fourth command synopsis version the optional argument
        <var>
          position
        </var>
         gives position of the text within the box. It may take the following values:
      </para>
      <table commandarg="code" spaces=" " endspaces=" ">
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                c
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <para>
              The
              <var>
                text
              </var>
               is centered (default).
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                l
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <para>
              The
              <var>
                text
              </var>
               is flush left.
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                r
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <para>
              Flush right.
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                s
              </itemformat>
            </item>
          </tableterm>
          <tableitemDefault handler: <!-- c xx TODO add a generic node to make clear that some statement may be -->
Default handler: <!-- c not true for some internationalization or some script. Eg. in Arabic -->
Default handler: <!-- c script or with microtype package I think that the strech also plays -->
Default handler: <!-- c on word width -->
>
            <para>
              Stretch the interword space in
              <var>
                text
              </var>
               across the entire
              <var>
                width
              </var>
              . The
              <var>
                text
              </var>
               must contain stretchable space for this to work. For instance, this could head a press release:
              <code>
                \noindent\makebox[\textwidth][s]
Default handler: &lbrace;
                \large\hfil IMMEDIATE\hfil RELEASE\hfil
Default handler: &rbrace;
              </code>
            </para>
          </tableitem>
        </tableentry>
      </table>
      <para>
        A common use of
        <code>
          \makebox
        </code>
         is to make zero-width text boxes. This puts the value of the quiz questions to the left of those questions.
      </para>
      <example endspaces=" ">
        <pre xml:space="preserve">
          \newcommand
Default handler: &lbrace;
          \pts
Default handler: &rbrace;
          [1]
Default handler: &lbrace;
          \makebox[0em][r]
Default handler: &lbrace;
          #1 points\hspace*
Default handler: &lbrace;
          1em
Default handler: &rbrace;
Default handler: &rbrace;
Default handler: &rbrace;
           \pts
Default handler: &lbrace;
          10
Default handler: &rbrace;
          What is the air-speed velocity of an unladen swallow? \pts
Default handler: &lbrace;
          90
Default handler: &rbrace;
          An African or European swallow?
        </pre>
      </example>
      <noindent/>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="880">
          <r>
            package
          </r>
          ,
          <code>
            TikZ
          </code>
        </indexterm>
      </cindex>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="881">
          <code>
            TikZ
          </code>
          <r>
            package
          </r>
        </indexterm>
      </cindex>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="882">
          <r>
            package
          </r>
          ,
          <code>
            Asymptote
          </code>
        </indexterm>
      </cindex>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="883">
          <code>
            Asymptote
          </code>
          <r>
            package
          </r>
        </indexterm>
      </cindex>
      <para>
        The right edge of the output
        <samp>
          10 points
        </samp>
         (note the ending space after
        <samp>
          points
        </samp>
        ) will be just before the
        <samp>
          What
        </samp>
        . You can use
        <code>
          \makebox
        </code>
         similarly when making graphics, such as in
        <code>
          TikZ
        </code>
         or
        <code>
          Asymptote
        </code>
        , where you put the edge of the text at a known location, regardless of the length of that text.
      </para>
      <para>
        For boxes with frames see
Default handler: &nbsp;
        <ref label="_005cfbox-_0026-_005cframebox">
          <xrefnodename>
            \fbox
            &
             \framebox
          </xrefnodename>
        </ref>
        . For colors see
Default handler: &nbsp;
        <ref label="Colored-boxes">
          <xrefnodename>
            Colored boxes
          </xrefnodename>
        </ref>
        .
      </para>
      <para>
        There is a related version of
        <code>
          \makebox
        </code>
         that is used within the
        <code>
          picture
        </code>
         environment, where the length is given in terms of
        <code>
          \unitlength
        </code>
         (
        <pxref label="_005cmakebox-_0028picture_0029">
          <xrefnodename>
            \makebox (picture)
          </xrefnodename>
        </pxref>
        ).
      </para>
      <para>
        As
        <var>
          text
        </var>
         is typeset in LR mode, neither a double backslash
        <code>
          \\
        </code>
         nor
        <code>
          \par
        </code>
         will give you a new line; for instance
        <code>
          \makebox
Default handler: &lbrace;
          abc def \\ ghi
Default handler: &rbrace;
        </code>
         outputs
        <samp>
          abc defghi
        </samp>
         while
        <code>
          \makebox
Default handler: &lbrace;
          abc def \par ghi
Default handler: &rbrace;
        </code>
         outputs
        <samp>
          abc def ghi
        </samp>
        , both on a single line. To get multiple lines see
Default handler: &nbsp;
        <ref label="_005cparbox">
          <xrefnodename>
            \parbox
          </xrefnodename>
        </ref>
         and
Default handler: &nbsp;
        <ref label="minipage">
          <xrefnodename>
            minipage
          </xrefnodename>
        </ref>
        .
      </para>
    </section>
    <node name="_005cfbox-_0026-_005cframebox" spaces=" ">
      <nodename>
        \fbox
        &
         \framebox
      </nodename>
      <nodenext automatic="on">
        \parbox
      </nodenext>
      <nodeprev automatic="on">
        \mbox
        &
         \makebox
      </nodeprev>
      <nodeup automatic="on">
        Boxes
      </nodeup>
    </node>
    <section spaces=" ">
      <sectiontitle>
        <code>
          \fbox
        </code>
        &
        <code>
          \framebox
        </code>
      </sectiontitle>
      <anchor name="_005cfbox">
        \fbox
      </anchor>
      <anchor name="_005cframebox">
        \framebox
      </anchor>
      <findex index="fn" spaces=" ">
        <indexterm index="fn" number="998" mergedindex="cp">
          \fbox
        </indexterm>
      </findex>
      <findex index="fn" spaces=" ">
        <indexterm index="fn" number="999" mergedindex="cp">
          \framebox
        </indexterm>
      </findex>
      <para>
        Synopses, one of:
      </para>
      <example endspaces=" ">
        <pre xml:space="preserve">
          \fbox
Default handler: &lbrace;
          <var>
            text
          </var>
Default handler: &rbrace;
           \framebox
Default handler: &lbrace;
          <var>
            text
          </var>
Default handler: &rbrace;
           \framebox[
          <var>
            width
          </var>
          ]
Default handler: &lbrace;
          <var>
            text
          </var>
Default handler: &rbrace;
           \framebox[
          <var>
            width
          </var>
          ][
          <var>
            position
          </var>
          ]
Default handler: &lbrace;
          <var>
            text
          </var>
Default handler: &rbrace;
        </pre>
      </example>
      <para>
        Create a box with an enclosing frame, four rules surrounding the
        <var>
          text
        </var>
        . These commands are the same as
        <code>
          \mbox
        </code>
         and
        <code>
          \makebox
        </code>
         except for the frame (
        <pxref label="_005cmbox-_0026-_005cmakebox">
          <xrefnodename>
            \mbox
            &
             \makebox
          </xrefnodename>
        </pxref>
        ). The
        <code>
          \fbox
        </code>
         command is robust, the
        <code>
          \framebox
        </code>
         command is fragile (
        <pxref label="_005cprotect">
          <xrefnodename>
            \protect
          </xrefnodename>
        </pxref>
        ).
      </para>
      <example endspaces=" ">
        <pre xml:space="preserve">
          \fbox
Default handler: &lbrace;
          Warning! No work shown, no credit given.
Default handler: &rbrace;
        </pre>
      </example>
      <noindent/>
      <paraDefault handler: &latex;
>
         puts the text into a box, the text cannot be hyphenated. Around that box, separated from it by a small gap, are four rules making a frame.
      </para>
      <para>
        The first two command invocations,
        <code>
          \fbox
Default handler: &lbrace;
          ...
Default handler: &rbrace;
        </code>
         and
        <code>
          \framebox
Default handler: &lbrace;
          ...
Default handler: &rbrace;
        </code>
        , are roughly the same. As to the third and fourth invocations, the optional arguments allow you to specify the box width as
        <var>
          width
        </var>
         and the position of the text inside that box as
        <var>
          position
        </var>
        .
        <xref label="_005cmbox-_0026-_005cmakebox">
          <xrefnodename>
            \mbox
            &
             \makebox
          </xrefnodename>
        </xref>
        , for the full description but here is an example creating an empty box that is 1/4
        <dmn>
          in
        </dmn>
         wide.
      </para>
      <example endspaces=" ">
        <pre xml:space="preserve">
          \setlength
Default handler: &lbrace;
          \fboxsep
Default handler: &rbrace;
Default handler: &lbrace;
          0pt
Default handler: &rbrace;
          \framebox[0.25in]
Default handler: &lbrace;
          \strut
Default handler: &rbrace;
Default handler: &rbrace;
        </pre>
      </example>
      <noindent/>
      <para>
        The
        <code>
          \strut
        </code>
         ensures a total height of
        <code>
          \baselineskip
        </code>
         (
        <pxref label="_005cstrut">
          <xrefnodename>
            \strut
          </xrefnodename>
        </pxref>
        ).
      </para>
      <para>
        These parameters determine the frame layout.
      </para>
      <ftable commandarg="code" spaces=" " endspaces=" ">
        <beforefirstitem>
          <anchor name="fbox-framebox-fboxrule">
            fbox framebox fboxrule
          </anchor>
        </beforefirstitem>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                <indexterm index="fn" number="1000" mergedindex="cp">
                  \fboxrule
                </indexterm>
                \fboxrule
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <findex index="fn" spaces=" ">
              <indexterm index="fn" number="1001" mergedindex="cp">
                frame, line width
              </indexterm>
            </findex>
            <findex index="fn" spaces=" ">
              <indexterm index="fn" number="1002" mergedindex="cp">
                frame rule width
              </indexterm>
            </findex>
            <cindex index="cp" spaces=" ">
              <indexterm index="cp" number="884">
                \fboxrule
              </indexterm>
            </cindex>
            <para>
              The thickness of the rules around the enclosed box. The default is 0.2
              <dmn>
                pt
              </dmn>
              . Change it with a command such as
              <code>
                \setlength
Default handler: &lbrace;
                \fboxrule
Default handler: &rbrace;
Default handler: &lbrace;
                0.8pt
Default handler: &rbrace;
              </code>
               (
              <pxref label="_005csetlength">
                <xrefnodename>
                  \setlength
                </xrefnodename>
              </pxref>
              ).
            </para>
            <anchor name="fbox-framebox-fboxsep">
              fbox framebox fboxsep
            </anchor>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                <indexterm index="fn" number="1003" mergedindex="cp">
                  \fboxsep
                </indexterm>
                \fboxsep
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <findex index="fn" spaces=" ">
              <indexterm index="fn" number="1004" mergedindex="cp">
                frame, separation from contents
              </indexterm>
            </findex>
            <cindex index="cp" spaces=" ">
              <indexterm index="cp" number="885">
                \fboxsep
              </indexterm>
            </cindex>
            <para>
              The distance from the frame to the enclosed box. The default is 3
              <dmn>
                pt
              </dmn>
              . Change it with a command such as
              <code>
                \setlength
Default handler: &lbrace;
                \fboxsep
Default handler: &rbrace;
Default handler: &lbrace;
                0pt
Default handler: &rbrace;
              </code>
               (
              <pxref label="_005csetlength">
                <xrefnodename>
                  \setlength
                </xrefnodename>
              </pxref>
              ). Setting it to 0
              <dmn>
                pt
              </dmn>
               is useful sometimes: this will put a frame around the picture with no white border.
            </para>
            <example endspaces=" ">
              <pre xml:space="preserve"Default handler: &lbrace;
>
                \setlength
Default handler: &lbrace;
                \fboxsep
Default handler: &rbrace;
Default handler: &lbrace;
                0pt
Default handler: &rbrace;
                % \framebox
Default handler: &lbrace;
                % \includegraphics[width=0.5\textwidth]
Default handler: &lbrace;
                prudence.jpg
Default handler: &rbrace;
Default handler: &rbrace;
Default handler: &rbrace;
              </pre>
            </example>
            <noindent/>
            <para>
              The extra curly braces keep the effect of the
              <code>
                \setlength
              </code>
               local.
            </para>
          </tableitem>
        </tableentry>
      </ftable>
      <para>
        As with
        <code>
          \mbox
        </code>
         and
        <code>
          \makebox
        </code>
        ,
Default handler: &latex;
         will not break lines in
        <var>
          text
        </var>
        . But this example has
Default handler: &latex;
         break lines to make a paragraph, and then frame the result.
      </para>
      <example endspaces=" ">
        <pre xml:space="preserve">
          \framebox
Default handler: &lbrace;
          % \begin
Default handler: &lbrace;
          minipage
Default handler: &rbrace;
Default handler: &lbrace;
          0.6\linewidth
Default handler: &rbrace;
           My dear, here we must run as fast as we can, just to stay in place. And if you wish to go anywhere you must run twice as fast as that. \end
Default handler: &lbrace;
          minipage
Default handler: &rbrace;
Default handler: &rbrace;
        </pre>
      </example>
      <para>
        <xref label="Colored-boxes">
          <xrefnodename>
            Colored boxes
          </xrefnodename>
        </xref>
        , for colors other than black and white.
      </para>
      <para>
        The
        <code>
          picture
        </code>
         environment has a version of the
        <code>
          \framebox
        </code>
         command where the units depend on
        <code>
          picture
        </code>
Default handler: &textrsquo;
        s
        <code>
          \unitlength
        </code>
         (
        <pxref label="_005cframebox-_0028picture_0029">
          <xrefnodename>
            \framebox (picture)
          </xrefnodename>
        </pxref>
        ).
      </para>
    </section>
    <node name="_005cparbox" spaces=" ">
      <nodename>
        \parbox
      </nodename>
      <nodenext automatic="on">
        \raisebox
      </nodenext>
      <nodeprev automatic="on">
        \fbox
        &
         \framebox
      </nodeprev>
      <nodeup automatic="on">
        Boxes
      </nodeup>
    </node>
    <section spaces=" ">
      <sectiontitle>
        <code>
          \parbox
        </code>
      </sectiontitle>
      <findex index="fn" spaces=" ">
        <indexterm index="fn" number="1005" mergedindex="cp">
          \parbox
        </indexterm>
      </findex>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="886">
          paragraph mode
        </indexterm>
      </cindex>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="887">
          paragraph, in a box
        </indexterm>
      </cindex>
      <para>
        Synopses, one of:
      </para>
      <example endspaces=" ">
        <pre xml:space="preserve">
          \parbox
Default handler: &lbrace;
          <var>
            width
          </var>
Default handler: &rbrace;
Default handler: &lbrace;
          <var>
            contents
          </var>
Default handler: &rbrace;
           \parbox[
          <var>
            position
          </var>
          ]
Default handler: &lbrace;
          <var>
            width
          </var>
Default handler: &rbrace;
Default handler: &lbrace;
          <var>
            contents
          </var>
Default handler: &rbrace;
           \parbox[
          <var>
            position
          </var>
          ][
          <var>
            height
          </var>
          ]
Default handler: &lbrace;
          <var>
            width
          </var>
Default handler: &rbrace;
Default handler: &lbrace;
          <var>
            contents
          </var>
Default handler: &rbrace;
           \parbox[
          <var>
            position
          </var>
          ][
          <var>
            height
          </var>
          ][
          <var>
            inner-pos
          </var>
          ]
Default handler: &lbrace;
          <var>
            width
          </var>
Default handler: &rbrace;
Default handler: &lbrace;
          <var>
            contents
          </var>
Default handler: &rbrace;
        </pre>
      </example>
      <para>
        Produce a box of text that is
        <var>
          width
        </var>
         wide. Use this command to make a box of small pieces of text, of a single paragraph. This command is fragile (
        <pxref label="_005cprotect">
          <xrefnodename>
            \protect
          </xrefnodename>
        </pxref>
        ).
      </para>
      <example endspaces=" ">
        <pre xml:space="preserve">
          \begin
Default handler: &lbrace;
          picture
Default handler: &rbrace;
          (0,0) ... \put(1,2)
Default handler: &lbrace;
          \parbox
Default handler: &lbrace;
          1.75in
Default handler: &rbrace;
Default handler: &lbrace;
          \raggedright Because the graph is a line on this semilog paper, the relationship is exponential.
Default handler: &rbrace;
Default handler: &rbrace;
           \end
Default handler: &lbrace;
          picture
Default handler: &rbrace;
        </pre>
      </example>
      <para>
        The
        <var>
          contents
        </var>
         are processed in a text mode (
        <pxref label="Modes">
          <xrefnodename>
            Modes
          </xrefnodename>
        </pxref>
        ) so
Default handler: &latex;
         will break lines to make a paragraph. But it won
Default handler: &textrsquo;
        t make multiple paragraphs; for that, use a
        <code>
          minipage
        </code>
         environment (
        <pxref label="minipage">
          <xrefnodename>
            minipage
          </xrefnodename>
        </pxref>
        ).
      </para>
      <para>
        The options for
        <code>
          \parbox
        </code>
         (except for
        <var>
          contents
        </var>
        ) are the same as those for
        <code>
          minipage
        </code>
        . For convenience a summary of the options is here but see
Default handler: &nbsp;
        <ref label="minipage">
          <xrefnodename>
            minipage
          </xrefnodename>
        </ref>
         for a complete description.
      </para>
      <para>
        There are two required arguments. The
        <var>
          width
        </var>
         is a rigid length (
        <pxref label="Lengths">
          <xrefnodename>
            Lengths
          </xrefnodename>
        </pxref>
        ). It sets the width of the box into which
Default handler: &latex;
         typesets
        <var>
          contents
        </var>
        . The
        <var>
          contents
        </var>
         is the text that is placed in that box. It should not have any paragraph-making components.
      </para>
      <para>
        There are three optional arguments,
        <var>
          position
        </var>
        ,
        <var>
          height
        </var>
        , and
        <var>
          inner-pos
        </var>
        . The
        <var>
          position
        </var>
         gives the vertical alignment of the
        <dfn>
          parbox
        </dfn>
         with respect to the surrounding material. The supported values are
        <code>
          c
        </code>
         or
        <code>
          m
        </code>
         to make the vertical center of the parbox lines up with the center of the adjacent text line (this is the default), or
        <code>
          t
        </code>
         to match the top line of the parbox with the baseline of the surrounding material, or
        <code>
          b
        </code>
         to match the bottom line.
      </para>
      <para>
        The optional argument
        <var>
          height
        </var>
         overrides the natural height of the box.
      </para>
      <para>
        The optional argument
        <var>
          inner-pos
        </var>
         controls the placement of
        <var>
          content
        </var>
         inside the
        <code>
          parbox
        </code>
        . Its default is the value of
        <var>
          position
        </var>
        . Its possible values are:
        <code>
          t
        </code>
         to put the
        <var>
          content
        </var>
         at the top of the box,
        <code>
          c
        </code>
         to put it in the vertical center,
        <code>
          b
        </code>
         to put it at the bottom of the box, and
        <code>
          s
        </code>
         to stretch it out vertically (for this, the text must contain vertically stretchable space).
      </para>
    </section>
    <node name="_005craisebox" spaces=" ">
      <nodename>
        \raisebox
      </nodename>
      <nodenext automatic="on">
        \sbox
        &
         \savebox
      </nodenext>
      <nodeprev automatic="on">
        \parbox
      </nodeprev>
      <nodeup automatic="on">
        Boxes
      </nodeup>
    </node>
    <section spaces=" ">
      <sectiontitle>
        <code>
          \raisebox
        </code>
      </sectiontitle>
      <findex index="fn" spaces=" ">
        <indexterm index="fn" number="1006" mergedindex="cp">
          \raisebox
        </indexterm>
      </findex>
      <para>
        Synopsis, one of:
      </para>
      <example endspaces=" ">
        <pre xml:space="preserve">
          \raisebox
Default handler: &lbrace;
          <var>
            distance
          </var>
Default handler: &rbrace;
Default handler: &lbrace;
          <var>
            text
          </var>
Default handler: &rbrace;
           \raisebox
Default handler: &lbrace;
          <var>
            distance
          </var>
Default handler: &rbrace;
          [
          <var>
            height
          </var>
          ]
Default handler: &lbrace;
          <var>
            text
          </var>
Default handler: &rbrace;
           \raisebox
Default handler: &lbrace;
          <var>
            distance
          </var>
Default handler: &rbrace;
          [
          <var>
            height
          </var>
          ][
          <var>
            depth
          </var>
          ]
Default handler: &lbrace;
          <var>
            text
          </var>
Default handler: &rbrace;
        </pre>
      </example>
      <para>
        Raise or lower
        <var>
          text
        </var>
        . This command is fragile (
        <pxref label="_005cprotect">
          <xrefnodename>
            \protect
          </xrefnodename>
        </pxref>
        ).
      </para>
      <para>
        This example makes a command for denoting the restriction of a function by lowering the vertical bar symbol.
      </para>
Default handler: <!-- c credit: egreg https://tex.stackexchange.com/a/278631/121234 -->
      <example endspaces=" ">
        <pre xml:space="preserve">
          \newcommand*\restricted[1]
Default handler: &lbrace;
          \raisebox
Default handler: &lbrace;
          -.5ex
Default handler: &rbrace;
Default handler: &lbrace;
          $|$
Default handler: &rbrace;
          _
Default handler: &lbrace;
          #1
Default handler: &rbrace;
Default handler: &rbrace;
           $f\restricted
Default handler: &lbrace;
          A
Default handler: &rbrace;
          $
        </pre>
      </example>
      <para>
        The first mandatory argument
        <var>
          distance
        </var>
         specifies how far to raise the second mandatory argument
        <var>
          text
        </var>
        . This is a rigid length (
        <pxref label="Lengths">
          <xrefnodename>
            Lengths
          </xrefnodename>
        </pxref>
        ). If it is negative then it lowers
        <var>
          text
        </var>
        . The
        <var>
          text
        </var>
         is processed in LR mode so it cannot contain line breaks (
        <pxref label="Modes">
          <xrefnodename>
            Modes
          </xrefnodename>
        </pxref>
        ).
      </para>
      <para>
        The optional arguments
        <var>
          height
        </var>
         and
        <var>
          depth
        </var>
         are dimensions. If they are specified, they override the natural height and depth of the box
Default handler: &latex;
         gets by typesetting
        <var>
          text
        </var>
        .
      </para>
      <anchor name="raisebox-depth">
        raisebox depth
      </anchor>
      <anchor name="raisebox-height">
        raisebox height
      </anchor>
      <anchor name="raisebox-width">
        raisebox width
      </anchor>
      <anchor name="raisebox-totalheight">
        raisebox totalheight
      </anchor>
      <para>
        In the arguments
        <var>
          distance
        </var>
        ,
        <var>
          height
        </var>
        , and
        <var>
          depth
        </var>
         you can use the following lengths that refer to the dimension of the box that
Default handler: &latex;
         gets on typesetting
        <var>
          text
        </var>
        :
        <code>
          \depth
        </code>
        ,
        <code>
          \height
        </code>
        ,
        <code>
          \width
        </code>
        ,
        <code>
          \totalheight
        </code>
         (this is the box
Default handler: &textrsquo;
        s height plus its depth).
      </para>
      <para>
        This will align two graphics on their top (
        <pxref label="Graphics">
          <xrefnodename>
            Graphics
          </xrefnodename>
        </pxref>
        ).
      </para>
Default handler: <!-- c credit: FAQ https://texfaq.org/FAQ-topgraph -->
      <example endspaces=" ">
        <pre xml:space="preserve">
          \usepackage
Default handler: &lbrace;
          graphicx,calc
Default handler: &rbrace;
           % in preamble ... \begin
Default handler: &lbrace;
          center
Default handler: &rbrace;
           \raisebox
Default handler: &lbrace;
          1ex-\height
Default handler: &rbrace;
Default handler: &lbrace;
          % \includegraphics[width=0.4\linewidth]
Default handler: &lbrace;
          lion.png
Default handler: &rbrace;
Default handler: &rbrace;
           \qquad \raisebox
Default handler: &lbrace;
          1ex-\height
Default handler: &rbrace;
Default handler: &lbrace;
          % \includegraphics[width=0.4\linewidth]
Default handler: &lbrace;
          meta.png
Default handler: &rbrace;
Default handler: &rbrace;
           \end
Default handler: &lbrace;
          center
Default handler: &rbrace;
        </pre>
      </example>
      <noindent/>
      <para>
        The first
        <code>
          \height
        </code>
         is the height of
        <file>
          lion.png
        </file>
         while the second is the height of
        <file>
          meta.png
        </file>
        .
      </para>
    </section>
    <node name="_005csbox-_0026-_005csavebox" spaces=" ">
      <nodename>
        \sbox
        &
         \savebox
      </nodename>
      <nodenext automatic="on">
        lrbox
      </nodenext>
      <nodeprev automatic="on">
        \raisebox
      </nodeprev>
      <nodeup automatic="on">
        Boxes
      </nodeup>
    </node>
    <section spaces=" ">
      <sectiontitle>
        <code>
          \sbox
        </code>
        &
        <code>
          \savebox
        </code>
      </sectiontitle>
      <anchor name="_005csbox">
        \sbox
      </anchor>
      <anchor name="_005csavebox">
        \savebox
      </anchor>
      <findex index="fn" spaces=" ">
        <indexterm index="fn" number="1007" mergedindex="cp">
          \sbox
        </indexterm>
      </findex>
      <findex index="fn" spaces=" ">
        <indexterm index="fn" number="1008" mergedindex="cp">
          \savebox
        </indexterm>
      </findex>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="888">
          box, save
        </indexterm>
      </cindex>
      <para>
        Synopsis, one of:
      </para>
      <example endspaces=" ">
        <pre xml:space="preserve">
          \sbox
Default handler: &lbrace;
          <var>
            box-cmd
          </var>
Default handler: &rbrace;
Default handler: &lbrace;
          <var>
            text
          </var>
Default handler: &rbrace;
           \savebox
Default handler: &lbrace;
          <var>
            box-cmd
          </var>
Default handler: &rbrace;
Default handler: &lbrace;
          <var>
            text
          </var>
Default handler: &rbrace;
           \savebox
Default handler: &lbrace;
          <var>
            box-cmd
          </var>
Default handler: &rbrace;
          [
          <var>
            width
          </var>
          ]
Default handler: &lbrace;
          <var>
            text
          </var>
Default handler: &rbrace;
           \savebox
Default handler: &lbrace;
          <var>
            box-cmd
          </var>
Default handler: &rbrace;
          [
          <var>
            width
          </var>
          ][
          <var>
            pos
          </var>
          ]
Default handler: &lbrace;
          <var>
            text
          </var>
Default handler: &rbrace;
        </pre>
      </example>
      <para>
        Typeset
        <var>
          text
        </var>
         just as with
        <code>
          \makebox
        </code>
         (
        <pxref label="_005cmbox-_0026-_005cmakebox">
          <xrefnodename>
            \mbox
            &
             \makebox
          </xrefnodename>
        </pxref>
        ) except that
Default handler: &latex;
         does not output it but instead saves it in a box register referred to by a variable named
        <var>
          box-cmd
        </var>
        . The variable name
        <var>
          box-cmd
        </var>
         begins with a backslash,
        <code>
          \
        </code>
        . You must have previously allocated the box register
        <var>
          box-cmd
        </var>
         with
        <code>
          \newsavebox
        </code>
         (
        <pxref label="_005cnewsavebox">
          <xrefnodename>
            \newsavebox
          </xrefnodename>
        </pxref>
        ). The
        <code>
          \sbox
        </code>
         command is robust while
        <code>
          \savebox
        </code>
         is fragile (
        <pxref label="_005cprotect">
          <xrefnodename>
            \protect
          </xrefnodename>
        </pxref>
        ).
      </para>
      <para>
        This creates and uses a box register.
      </para>
      <example endspaces=" ">
        <pre xml:space="preserve">
          \newsavebox
Default handler: &lbrace;
          \fullname
Default handler: &rbrace;
           \sbox
Default handler: &lbrace;
          \fullname
Default handler: &rbrace;
Default handler: &lbrace;
          John Jacob Jingleheimer Schmidt
Default handler: &rbrace;
           ... \usebox
Default handler: &lbrace;
          \fullname
Default handler: &rbrace;
          ! His name is my name, too! Whenever we go out, the people always shout! There goes \usebox
Default handler: &lbrace;
          \fullname
Default handler: &rbrace;
          ! Ya da da da da da da.
        </pre>
      </example>
      <noindent/>
      <para>
        One advantage of using and reusing a box register over a
        <code>
          \newcommand
        </code>
         macro variable is efficiency, that
Default handler: &latex;
         need not repeatedly retypeset the contents. See the example below.
      </para>
      <para>
        The first two command invocations shown above,
        <code>
          \sbox
Default handler: &lbrace;
          <var>
            box-cmd
          </var>
Default handler: &rbrace;
Default handler: &lbrace;
          <var>
            text
          </var>
Default handler: &rbrace;
        </code>
         and
        <code>
          \savebox
Default handler: &lbrace;
          <var>
            box-cmd
          </var>
Default handler: &rbrace;
Default handler: &lbrace;
          <var>
            text
          </var>
Default handler: &rbrace;
        </code>
        , are roughly the same. As to the third and fourth, the optional arguments allow you to specify the box width as
        <var>
          width
        </var>
        , and the position of the text inside that box as
        <var>
          position
        </var>
        .
        <xref label="_005cmbox-_0026-_005cmakebox">
          <xrefnodename>
            \mbox
            &
             \makebox
          </xrefnodename>
        </xref>
        , for the full description.
      </para>
      <para>
        In the
        <code>
          \sbox
        </code>
         and
        <code>
          \savebox
        </code>
         commands the
        <var>
          text
        </var>
         is typeset in LR mode so it does not have line breaks (
        <pxref label="Modes">
          <xrefnodename>
            Modes
          </xrefnodename>
        </pxref>
        ). If you use these then
Default handler: &latex;
         doesn
Default handler: &textrsquo;
        t give you an error but it ignores what you want: if you enter
        <code>
          \sbox
Default handler: &lbrace;
          \newreg
Default handler: &rbrace;
Default handler: &lbrace;
          test \\ test
Default handler: &rbrace;
        </code>
         and
        <code>
          \usebox
Default handler: &lbrace;
          \newreg
Default handler: &rbrace;
        </code>
         then you get
        <samp>
          testtest
        </samp>
        , while if you enter
        <code>
          \sbox
Default handler: &lbrace;
          \newreg
Default handler: &rbrace;
Default handler: &lbrace;
          test \par test
Default handler: &rbrace;
        </code>
         and
        <code>
          \usebox
Default handler: &lbrace;
          \newreg
Default handler: &rbrace;
        </code>
         then you get
        <samp>
          test test
        </samp>
        , but no error or warning. To fix this use a
        <code>
          \parbox
        </code>
         or
        <code>
          minipage
        </code>
         as here.
      </para>
Default handler: <!-- c credit: egreg https://tex.stackexchange.com/a/41668/121234 -->
      <example endspaces=" ">
        <pre xml:space="preserve">
          \newsavebox
Default handler: &lbrace;
          \areg
Default handler: &rbrace;
           \savebox
Default handler: &lbrace;
          \areg
Default handler: &rbrace;
Default handler: &lbrace;
          % \begin
Default handler: &lbrace;
          minipage
Default handler: &rbrace;
Default handler: &lbrace;
          \linewidth
Default handler: &rbrace;
           \begin
Default handler: &lbrace;
          enumerate
Default handler: &rbrace;
           \item First item \item Second item \end
Default handler: &lbrace;
          enumerate
Default handler: &rbrace;
           \end
Default handler: &lbrace;
          minipage
Default handler: &rbrace;
Default handler: &rbrace;
           ... \usebox
Default handler: &lbrace;
          \areg
Default handler: &rbrace;
        </pre>
      </example>
      <para>
        As an example of the efficiency of reusing a register
Default handler: &textrsquo;
        s contents, this puts the same picture on each page of the document by putting it in the header.
Default handler: &latex;
         only typesets it once.
      </para>
      <example endspaces=" ">
        <pre xml:space="preserve">
          \usepackage
Default handler: &lbrace;
          graphicx
Default handler: &rbrace;
           % all this in the preamble \newsavebox
Default handler: &lbrace;
          \sealreg
Default handler: &rbrace;
           \savebox
Default handler: &lbrace;
          \sealreg
Default handler: &rbrace;
Default handler: &lbrace;
          % \setlength
Default handler: &lbrace;
          \unitlength
Default handler: &rbrace;
Default handler: &lbrace;
          1in
Default handler: &rbrace;
          % \begin
Default handler: &lbrace;
          picture
Default handler: &rbrace;
          (0,0)% \put(1.5,-2.5)
Default handler: &lbrace;
          % \begin
Default handler: &lbrace;
          tabular
Default handler: &rbrace;
Default handler: &lbrace;
          c
Default handler: &rbrace;
           \includegraphics[height=2in]
Default handler: &lbrace;
          companylogo.png
Default handler: &rbrace;
           \\ Office of the President \end
Default handler: &lbrace;
          tabular
Default handler: &rbrace;
Default handler: &rbrace;
           \end
Default handler: &lbrace;
          picture
Default handler: &rbrace;
          %
Default handler: &rbrace;
           \markright
Default handler: &lbrace;
          \usebox
Default handler: &lbrace;
          \sealreg
Default handler: &rbrace;
Default handler: &rbrace;
           \pagestyle
Default handler: &lbrace;
          headings
Default handler: &rbrace;
        </pre>
      </example>
      <noindent/>
      <para>
        The
        <code>
          picture
        </code>
         environment is good for fine-tuning the placement.
      </para>
      <para>
        If the register
        <code>
          \noreg
        </code>
         has not already been defined then you get something like
        <samp>
          Undefined control sequence.
          <
          argument
          >
           \noreg
        </samp>
        .
      </para>
    </section>
    <node name="lrbox" spaces=" ">
      <nodename>
        lrbox
      </nodename>
      <nodenext automatic="on">
        \usebox
      </nodenext>
      <nodeprev automatic="on">
        \sbox
        &
         \savebox
      </nodeprev>
      <nodeup automatic="on">
        Boxes
      </nodeup>
    </node>
    <section spaces=" ">
      <sectiontitle>
        <code>
          lrbox
        </code>
      </sectiontitle>
      <findex index="fn" spaces=" ">
        <indexterm index="fn" number="1009" mergedindex="cp">
          lrbox
        </indexterm>
      </findex>
      <para>
        Synopsis:
      </para>
      <example endspaces=" ">
        <pre xml:space="preserve">
          \begin
Default handler: &lbrace;
          lrbox
Default handler: &rbrace;
Default handler: &lbrace;
          <var>
            box-cmd
          </var>
Default handler: &rbrace;
          <var>
            text
          </var>
           \end
Default handler: &lbrace;
          lrbox
Default handler: &rbrace;
        </pre>
      </example>
      <para>
        This is the environment form of the
        <code>
          \sbox
        </code>
         and
        <code>
          \savebox
        </code>
         commands, and is equivalent to them.
        <xref label="_005csbox-_0026-_005csavebox">
          <xrefnodename>
            \sbox
            &
             \savebox
          </xrefnodename>
        </xref>
        , for the full description.
      </para>
      <para>
        The
        <var>
          text
        </var>
         inside the environment is saved in the box register referred to by variable
        <code>
          <var>
            box-cmd
          </var>
        </code>
        . The variable name
        <var>
          box-cmd
        </var>
         must begin with a backslash,
        <code>
          \
        </code>
        . You must allocate this box register in advance with
        <code>
          \newsavebox
        </code>
         (
        <pxref label="_005cnewsavebox">
          <xrefnodename>
            \newsavebox
          </xrefnodename>
        </pxref>
        ). In this example the environment is convenient for entering the
        <code>
          tabular
        </code>
        .
      </para>
      <example endspaces=" ">
        <pre xml:space="preserve">
          \newsavebox
Default handler: &lbrace;
          \jhreg
Default handler: &rbrace;
           \begin
Default handler: &lbrace;
          lrbox
Default handler: &rbrace;
Default handler: &lbrace;
          \jhreg
Default handler: &rbrace;
           \begin
Default handler: &lbrace;
          tabular
Default handler: &rbrace;
Default handler: &lbrace;
          c
Default handler: &rbrace;
           \includegraphics[height=1in]
Default handler: &lbrace;
          jh.png
Default handler: &rbrace;
           \\ Jim Hef
Default handler: &lbrace;
Default handler: &rbrace;
          feron \end
Default handler: &lbrace;
          tabular
Default handler: &rbrace;
           \end
Default handler: &lbrace;
          lrbox
Default handler: &rbrace;
           ... \usebox
Default handler: &lbrace;
          \jhreg
Default handler: &rbrace;
        </pre>
      </example>
    </section>
    <node name="_005cusebox" spaces=" ">
      <nodename>
        \usebox
      </nodename>
      <nodeprev automatic="on">
        lrbox
      </nodeprev>
      <nodeup automatic="on">
        Boxes
      </nodeup>
    </node>
    <section spaces=" ">
      <sectiontitle>
        <code>
          \usebox
        </code>
      </sectiontitle>
      <findex index="fn" spaces=" ">
        <indexterm index="fn" number="1010" mergedindex="cp">
          \usebox
        </indexterm>
      </findex>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="889">
          box, use saved box
        </indexterm>
      </cindex>
      <para>
        Synopsis:
      </para>
      <example endspaces=" ">
        <pre xml:space="preserve">
          \usebox
Default handler: &lbrace;
          <var>
            box-cmd
          </var>
Default handler: &rbrace;
        </pre>
      </example>
      <para>
        Produce the box most recently saved in the box register
        <var>
          box-cmd
        </var>
         by the commands
        <code>
          \sbox
        </code>
         or
        <code>
          \savebox
        </code>
        , or the
        <code>
          lrbox
        </code>
         environment. For more information and examples,
        <pxref label="_005csbox-_0026-_005csavebox">
          <xrefnodename>
            \sbox
            &
             \savebox
          </xrefnodename>
        </pxref>
        . (Note that the variable name
        <var>
          box-cmd
        </var>
         starts with a backslash,
        <code>
          \
        </code>
        .) This command is robust (
        <pxref label="_005cprotect">
          <xrefnodename>
            \protect
          </xrefnodename>
        </pxref>
        ).
      </para>
    </section>
  </chapter>
  <node name="Graphics" spaces=" ">
    <nodename>
      Graphics
    </nodename>
    <nodenext automatic="on">
      Color
    </nodenext>
    <nodeprev automatic="on">
      Boxes
    </nodeprev>
    <nodeup automatic="on">
      Top
    </nodeup>
  </node>
  <chapter spaces=" ">
    <sectiontitle>
      Graphics
    </sectiontitle>
    <cindex index="cp" spaces=" ">
      <indexterm index="cp" number="890">
        graphics
      </indexterm>
    </cindex>
    <cindex index="cp" spaces=" ">
      <indexterm index="cp" number="891">
        graphics package
      </indexterm>
    </cindex>
    <para>
      You can use graphics such as PNG or PDF files in your
Default handler: &latex;
       document. You need an additional package, which comes standard with
Default handler: &latex;
      . This example is the short how-to.
    </para>
    <example endspaces=" ">
      <pre xml:space="preserve">
        \include
Default handler: &lbrace;
        graphicx
Default handler: &rbrace;
         % goes in the preamble ... \includegraphics[width=0.5\linewidth]
Default handler: &lbrace;
        plot.pdf
Default handler: &rbrace;
      </pre>
    </example>
    <para>
      To use the commands described here your document preamble must contain either
      <code>
        \usepackage
Default handler: &lbrace;
        graphicx
Default handler: &rbrace;
      </code>
       or
      <code>
        \usepackage
Default handler: &lbrace;
        graphics
Default handler: &rbrace;
      </code>
      . Most of the time,
      <code>
        graphicx
      </code>
       is the better choice.
    </para>
    <para>
      Graphics come in two main types, raster and vector.
Default handler: &latex;
       can use both. In raster graphics the file contains an entry for each location in an array, describing what color it is. An example is a photograph in JPG format. In vector graphics, the file contains a list of instructions such as
      <samp>
        draw a circle with this radius and that center
      </samp>
      . An example is a line drawing produced by the Asymptote program, in PDF format. Generally vector graphics are more useful because you can rescale their size without pixelation or other problems, and because they often have a smaller size.
    </para>
    <para>
      There are systems particularly well-suited to make graphics for a
Default handler: &latex;
       document. For example, these allow you to use the same fonts as in your document.
Default handler: &latex;
       comes with a
      <code>
        picture
      </code>
       environment (
      <pxref label="picture">
        <xrefnodename>
          picture
        </xrefnodename>
      </pxref>
      ) that has simple capabilities. Besides that, there are other ways to include the graphic-making commands in the document. Two such systems are the PSTricks and TikZ packages. There are also systems external to
Default handler: &latex;
      , that generate a graphic that you include using the commands of this chapter. Two that use a programming language are Asymptote and MetaPost. One that uses a graphical interface is Xfig. Full description of these systems is outside the scope of this document; see their documentation on CTAN.
    </para>
    <menu endspaces=" ">
      <menuentry>
        <menuleadingtext>
          *
        </menuleadingtext>
        <menunode>
          Graphics package options
        </menunode>
        <menuseparator>
          ::
        </menuseparator>
        <menudescription>
          <pre xml:space="preserve">
            Options when you load the package.
          </pre>
        </menudescription>
      </menuentry>
      <menuentry>
        <menuleadingtext>
          *
        </menuleadingtext>
        <menunode>
          Graphics package configuration
        </menunode>
        <menuseparator>
          ::
        </menuseparator>
        <menudescription>
          <pre xml:space="preserve">
            Where to look for files, which file types.
          </pre>
        </menudescription>
      </menuentry>
      <menuentry>
        <menuleadingtext>
          *
        </menuleadingtext>
        <menunode>
          Commands for graphics
        </menunode>
        <menuseparator>
          ::
        </menuseparator>
        <menudescription>
          <pre xml:space="preserve">
            The available commands.
          </pre>
        </menudescription>
      </menuentry>
    </menu>
    <node name="Graphics-package-options" spaces=" ">
      <nodename>
        Graphics package options
      </nodename>
      <nodenext automatic="on">
        Graphics package configuration
      </nodenext>
      <nodeup automatic="on">
        Graphics
      </nodeup>
    </node>
    <section spaces=" ">
      <sectiontitle>
        <code>
          graphics
        </code>
         package options
      </sectiontitle>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="892">
          graphics package options
        </indexterm>
      </cindex>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="893">
          options, graphics package
        </indexterm>
      </cindex>
      <para>
        Synopsis (must be in the document preamble):
      </para>
      <example endspaces=" ">
        <pre xml:space="preserve">
          \usepackage[
          <var>
            comma-separated option list
          </var>
          ]
Default handler: &lbrace;
          graphics
Default handler: &rbrace;
        </pre>
      </example>
      <noindent/>
      <para>
        or
      </para>
      <example endspaces=" ">
        <pre xml:space="preserve">
          \usepackage[
          <var>
            comma-separated option list
          </var>
          ]
Default handler: &lbrace;
          graphicx
Default handler: &rbrace;
        </pre>
      </example>
      <para>
        The
        <code>
          graphicx
        </code>
         package has a format for optional arguments to the
        <code>
          \includegraphics
        </code>
         command that is convenient (it is the key-value format), so it is the better choice for new documents. When you load the
        <code>
          graphics
        </code>
         or
        <code>
          graphicx
        </code>
         package with
        <code>
          \usepackage
        </code>
         there are two kinds of available options.
      </para>
      <para>
        The first is that
Default handler: &latex;
         does not contain information about different output systems but instead depends on information stored in a
        <dfn>
          printer driver
        </dfn>
         file. Normally you should not specify the driver option in the document, and instead rely on your system
Default handler: &textrsquo;
        s default. One advantage of this is that it makes the document portable across systems.
      </para>
      <para>
        For completeness here is a list of the drivers. The currently relevant ones are:
        <file>
          dvipdfmx
        </file>
        ,
        <file>
          dvips
        </file>
        ,
        <file>
          dvisvgm
        </file>
        ,
        <file>
          luatex
        </file>
        ,
        <file>
          pdftex
        </file>
        ,
        <file>
          xetex
        </file>
        . The two
        <file>
          xdvi
        </file>
         and
        <file>
          oztex
        </file>
         are essentially aliases for
        <file>
          dvips
        </file>
         (and
        <file>
          xdvi
        </file>
         is monochrome). Ones that should not be used for new systems are:
        <file>
          dvipdf
        </file>
        ,
        <file>
          dvipdfm
        </file>
        ,
        <file>
          dviwin
        </file>
        ,
        <file>
          dvipsone
        </file>
        ,
        <file>
          emtex
        </file>
        ,
        <file>
          pctexps
        </file>
        ,
        <file>
          pctexwin
        </file>
        ,
        <file>
          pctexhp
        </file>
        ,
        <file>
          pctex32
        </file>
        ,
        <file>
          truetex
        </file>
        ,
        <file>
          tcidvi
        </file>
        ,
        <file>
          vtex
        </file>
         (and
        <file>
          dviwindo
        </file>
         is an alias for
        <file>
          dvipsone
        </file>
        ). These are stored in files with a
        <file>
          .def
        </file>
         extension, such as
        <file>
          pdftex.def
        </file>
        .
      </para>
      <para>
        The second kind of options are below.
      </para>
      <table commandarg="code" spaces=" " endspaces=" ">
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                demo
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <para>
              Instead of an image file,
Default handler: &latex;
               puts in a 150
Default handler: &nbsp;
              pt by 100
Default handler: &nbsp;
              pt rectangle (unless another size is specified in the
              <code>
                \includegraphics
              </code>
               command).
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                draft
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <para>
              For each graphic file, it is not shown but instead its file name is printed in a box of the correct size. In order to determine the size, the file must be present.
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                final
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <para>
              (Default) Override any previous
              <code>
                draft
              </code>
               option, so that the document shows the contents of the graphic files.
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                hiderotate
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <para>
              Do not show rotated text. (This allows for the possibility that a previewer does not have the capability to rotate text.)
Default handler: <!-- c what does it show? -->
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                hidescale
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <para>
              Do not show scaled text. (This allows for the possibility that a previewer does not have the capability to scale.)
Default handler: <!-- c what does it show? -->
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                hiresbb
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <para>
              In a PS or EPS file the graphic size may be specified in two ways. The
              <code>
                %%BoundingBox
              </code>
               lines describe the graphic size using integer multiples of a PostScript point, that is, integer multiples of 1/72 inch. A later addition to the PostScript language allows decimal multiples, such as 1.23, in
              <code>
                %%HiResBoundingBox
              </code>
               lines. This option has
Default handler: &latex;
               to read the size from the latter.
            </para>
          </tableitem>
        </tableentry>
      </table>
    </section>
    <node name="Graphics-package-configuration" spaces=" ">
      <nodename>
        Graphics package configuration
      </nodename>
      <nodenext automatic="on">
        Commands for graphics
      </nodenext>
      <nodeprev automatic="on">
        Graphics package options
      </nodeprev>
      <nodeup automatic="on">
        Graphics
      </nodeup>
    </node>
    <section spaces=" ">
      <sectiontitle>
        <code>
          graphics
        </code>
         package configuration
      </sectiontitle>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="894">
          graphics
        </indexterm>
      </cindex>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="895">
          graphics package
        </indexterm>
      </cindex>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="896">
          configuration, graphics package
        </indexterm>
      </cindex>
      <para>
        These commands configure the way
Default handler: &latex;
         searches the file system for the graphic.
      </para>
      <para>
        The behavior of file system search code is necessarily platform dependent. In this document we cover GNU/Linux, Macintosh, and Windows, as those systems are typically configured. For other situations consult the documentation in
        <file>
          grfguide.pdf
        </file>
        , or the
Default handler: &latex;
         source, or your
Default handler: &tex;
         distribution
Default handler: &textrsquo;
        s documentation.
      </para>
      <menu endspaces=" ">
        <menuentry>
          <menuleadingtext>
            *
          </menuleadingtext>
          <menunode>
            \graphicspath
          </menunode>
          <menuseparator>
            ::
          </menuseparator>
          <menudescription>
            <pre xml:space="preserve">
              Directories to search.
            </pre>
          </menudescription>
        </menuentry>
        <menuentry>
          <menuleadingtext>
            *
          </menuleadingtext>
          <menunode>
            \DeclareGraphicsExtensions
          </menunode>
          <menuseparator>
            ::
          </menuseparator>
          <menudescription>
            <pre xml:space="preserve">
              File types, such as JPG or EPS.
            </pre>
          </menudescription>
        </menuentry>
        <menuentry>
          <menuleadingtext>
            *
          </menuleadingtext>
          <menunode>
            \DeclareGraphicsRule
          </menunode>
          <menuseparator>
            ::
          </menuseparator>
          <menudescription>
            <pre xml:space="preserve">
              How to handle file types.
            </pre>
          </menudescription>
        </menuentry>
      </menu>
      <node name="_005cgraphicspath" spaces=" ">
        <nodename>
          \graphicspath
        </nodename>
        <nodenext automatic="on">
          \DeclareGraphicsExtensions
        </nodenext>
        <nodeup automatic="on">
          Graphics package configuration
        </nodeup>
      </node>
      <subsection spaces=" ">
        <sectiontitle>
          <code>
            \graphicspath
          </code>
        </sectiontitle>
        <findex index="fn" spaces=" ">
          <indexterm index="fn" number="1011" mergedindex="cp">
            \graphicspath
          </indexterm>
        </findex>
        <para>
          Synopsis:
        </para>
        <example endspaces=" ">
          <pre xml:space="preserve">
            \graphicspath
Default handler: &lbrace;
            <var>
              list of directories inside curly braces
            </var>
Default handler: &rbrace;
          </pre>
        </example>
        <para>
          Declare a list of directories to search for graphics files. This allows you to later say something like
          <code>
            \includegraphics
Default handler: &lbrace;
            lion.png
Default handler: &rbrace;
          </code>
           instead of having to give its path.
        </para>
        <paraDefault handler: &latex;
>
           always looks for graphic files first in the current directory (and the output directory, if specified;
          <pxref label="output-directory">
            <xrefnodename>
              output directory
            </xrefnodename>
          </pxref>
          ). The declaration below tells the system to then look in the subdirectory
          <file>
            pix
          </file>
          , and then
          <file>
            ../pix
          </file>
          .
        </para>
        <example endspaces=" ">
          <pre xml:space="preserve">
            \usepackage
Default handler: &lbrace;
            graphicx
Default handler: &rbrace;
             % or graphics; put in preamble ... \graphicspath
Default handler: &lbrace;
Default handler: &lbrace;
            pix/
Default handler: &rbrace;
Default handler: &lbrace;
            ../pix/
Default handler: &rbrace;
Default handler: &rbrace;
          </pre>
        </example>
        <para>
          The
          <code>
            \graphicspath
          </code>
           declaration is optional. If you don
Default handler: &textrsquo;
          t include it then
Default handler: &latex;
Default handler: &textrsquo;
          s default is to search all of the places that it usually looks for a file (it uses
Default handler: &latex;
Default handler: &textrsquo;
          s
          <code>
            \input
Default handler: &arobase;
            path
          </code>
          ). In particular, in this case one of the places it looks is the current directory.
        </para>
        <para>
          Enclose each directory name in curly braces; for example, above it says
          <samp>
            <codeDefault handler: &lbrace;
>
              pix
Default handler: &rbrace;
            </code>
          </samp>
          . Do this even if there is only one directory. Each directory name must end in a forward slash,
          <file>
            /
          </file>
          . This is true even on Windows, where good practice is to use forward slashes for all the directory separators since it makes the document portable to other platforms. If you have spaces in your directory name then use double quotes, as with
          <codeDefault handler: &lbrace;
>
            "
            my docs/
            "
Default handler: &rbrace;
          </code>
          . Getting one of these rules wrong will cause
Default handler: &latex;
           to report
          <code>
            Error: File `
            <var>
              filename
            </var>
            ' not found
          </code>
          .
        </para>
        <para>
          Basically, the algorithm is that with this example, after looking in the current directory,
        </para>
        <example endspaces=" ">
          <pre xml:space="preserve">
            \graphicspath
Default handler: &lbrace;
Default handler: &lbrace;
            pix/
Default handler: &rbrace;
Default handler: &lbrace;
            ../pix/
Default handler: &rbrace;
Default handler: &rbrace;
             ... \usepackage
Default handler: &lbrace;
            lion.png
Default handler: &rbrace;
          </pre>
        </example>
        <noindent/>
        <para>
          for each of the listed directories,
Default handler: &latex;
           concatenates it with the filename and searches for the result, checking for
          <file>
            pix/lion.png
          </file>
           and then
          <file>
            ../pix/lion.png
          </file>
          . This algorithm means that the
          <code>
            \graphicspath
          </code>
           command does not recursively search subdirectories: if you issue
          <code>
            \graphicspath
Default handler: &lbrace;
Default handler: &lbrace;
            a/
Default handler: &rbrace;
Default handler: &rbrace;
          </code>
           and the graphic is in
          <file>
            a/b/lion.png
          </file>
           then
Default handler: &latex;
           will not find it. It also means that you can use absolute paths such as
          <code>
            \graphicspath
Default handler: &lbrace;
Default handler: &lbrace;
            /home/jim/logos/
Default handler: &rbrace;
Default handler: &rbrace;
          </code>
           or
          <code>
            \graphicspath
Default handler: &lbrace;
Default handler: &lbrace;
            C:/Users/Albert/Pictures/
Default handler: &rbrace;
Default handler: &rbrace;
          </code>
          . However, using these means that the document is not portable. (You could preserve portability by adjusting your
Default handler: &tex;
           system settings configuration file parameter
          <code>
            TEXINPUTS
          </code>
          ; see the documentation of your system.)
        </para>
        <para>
          You can use
          <code>
            \graphicspath
          </code>
           anywhere in the document. You can use it more than once. Show its value with
          <code>
            \makeatletter\typeout
Default handler: &lbrace;
            \Ginput
Default handler: &arobase;
            path
Default handler: &rbrace;
            \makeatother
          </code>
          .
        </para>
        <para>
          The directories are taken with respect to the base file. That is, suppose that you are working on a document based on
          <file>
            book/book.tex
          </file>
           and it contains
          <code>
            \include
Default handler: &lbrace;
            chapters/chap1
Default handler: &rbrace;
          </code>
          . If in
          <file>
            chap1.tex
          </file>
           you put
          <code>
            \graphicspath
Default handler: &lbrace;
Default handler: &lbrace;
            plots/
Default handler: &rbrace;
Default handler: &rbrace;
          </code>
           then
Default handler: &latex;
           will not search for graphics in
          <file>
            book/chapters/plots
          </file>
          , but instead in
          <file>
            book/plots
          </file>
          .
        </para>
      </subsection>
      <node name="_005cDeclareGraphicsExtensions" spaces=" ">
        <nodename>
          \DeclareGraphicsExtensions
        </nodename>
        <nodenext automatic="on">
          \DeclareGraphicsRule
        </nodenext>
        <nodeprev automatic="on">
          \graphicspath
        </nodeprev>
        <nodeup automatic="on">
          Graphics package configuration
        </nodeup>
      </node>
      <subsection spaces=" ">
        <sectiontitle>
          <code>
            \DeclareGraphicsExtensions
          </code>
        </sectiontitle>
        <findex index="fn" spaces=" ">
          <indexterm index="fn" number="1012" mergedindex="cp">
            \DeclareGraphicsExtensions
          </indexterm>
        </findex>
        <para>
          Synopses:
        </para>
        <example endspaces=" ">
          <pre xml:space="preserve">
            \DeclareGraphicsExtensions
Default handler: &lbrace;
            <var>
              comma-separated list of file extensions
            </var>
Default handler: &rbrace;
          </pre>
        </example>
        <para>
          Declare the filename extensions to try. This allows you to specify the order in which to choose graphic formats when you include graphic files by giving the filename without the extension, as in
          <code>
            \includegraphics
Default handler: &lbrace;
            functionplot
Default handler: &rbrace;
          </code>
          .
        </para>
        <para>
          In this example,
Default handler: &latex;
           will find files in the PNG format before PDF files.
        </para>
        <example endspaces=" ">
          <pre xml:space="preserve">
            \DeclareGraphicsExtensions
Default handler: &lbrace;
            .png,PNG,.pdf,.PDF
Default handler: &rbrace;
             ... \includegraphics
Default handler: &lbrace;
            lion
Default handler: &rbrace;
             % will find
            <file>
              lion.png
            </file>
             before
            <file>
              lion.pdf
            </file>
          </pre>
        </example>
        <noindent/>
        <para>
          Because the filename
          <file>
            lion
          </file>
           does not have a period,
Default handler: &latex;
           uses the extension list. For each directory in the graphics path (
          <pxref label="_005cgraphicspath">
            <xrefnodename>
              \graphicspath
            </xrefnodename>
          </pxref>
          ),
Default handler: &latex;
           will try the extensions in the order given. If it does not find such a file after trying all the directories and extensions then it reports
          <samp>
            ! LaTeX Error: File `
            <file>
              lion
            </file>
            ' not found
          </samp>
          . Note that you must include the periods at the start of the extensions.
        </para>
        <para>
          Because GNU/Linux and Macintosh filenames are case sensitive, the list of file extensions is case sensitive on those platforms. The Windows platform is not case sensitive.
        </para>
        <para>
          You are not required to include
          <code>
            \DeclareGraphicsExtensions
          </code>
           in your document; the printer driver has a sensible default. For example, the most recent
          <file>
            pdftex.def
          </file>
           has this extension list.
        </para>
        <example endspaces=" ">
          <pre xml:space="preserve">
            .pdf,.png,.jpg,.mps,.jpeg,.jbig2,.jb2,.PDF,.PNG,.JPG,.JPEG,.JBIG2,.JB2
          </pre>
        </example>
        <cindex index="cp" spaces=" ">
          <indexterm index="cp" number="897">
            <r>
              package
            </r>
            ,
            <code>
              grfext
            </code>
          </indexterm>
        </cindex>
        <cindex index="cp" spaces=" ">
          <indexterm index="cp" number="898">
            <code>
              grfext
            </code>
            <r>
              package
            </r>
          </indexterm>
        </cindex>
        <para>
          To change the order, use the
          <code>
            grfext
          </code>
           package.
        </para>
        <para>
          You can use this command anywhere in the document. You can use it more than once. Show its value with
          <code>
            \makeatletter\typeout
Default handler: &lbrace;
            \Gin
Default handler: &arobase;
            extensions
Default handler: &rbrace;
            \makeatother
          </code>
          .
        </para>
      </subsection>
      <node name="_005cDeclareGraphicsRule" spaces=" ">
        <nodename>
          \DeclareGraphicsRule
        </nodename>
        <nodeprev automatic="on">
          \DeclareGraphicsExtensions
        </nodeprev>
        <nodeup automatic="on">
          Graphics package configuration
        </nodeup>
      </node>
      <subsection spaces=" ">
        <sectiontitle>
          <code>
            \DeclareGraphicsRule
          </code>
        </sectiontitle>
        <findex index="fn" spaces=" ">
          <indexterm index="fn" number="1013" mergedindex="cp">
            \DeclareGraphicsRule
          </indexterm>
        </findex>
        <para>
          Synopsis:
        </para>
        <example endspaces=" ">
          <pre xml:space="preserve">
            \DeclareGraphicsRule
Default handler: &lbrace;
            <var>
              extension
            </var>
Default handler: &rbrace;
Default handler: &lbrace;
            <var>
              type
            </var>
Default handler: &rbrace;
Default handler: &lbrace;
            <var>
              size-file extension
            </var>
Default handler: &rbrace;
Default handler: &lbrace;
            <var>
              command
            </var>
Default handler: &rbrace;
          </pre>
        </example>
        <para>
          Declare how to handle graphic files whose names end in
          <var>
            extension
          </var>
          .
        </para>
        <para>
          This example declares that all files with names of the form
          <file>
            filename-without-dot.mps
          </file>
           will be treated as output from MetaPost, meaning that the printer driver will use its MetaPost-handling code to input the file.
        </para>
        <example endspaces=" ">
          <pre xml:space="preserve">
            \DeclareGraphicsRule
Default handler: &lbrace;
            .mps
Default handler: &rbrace;
Default handler: &lbrace;
            mps
Default handler: &rbrace;
Default handler: &lbrace;
            .mps
Default handler: &rbrace;
Default handler: &lbrace;
Default handler: &rbrace;
          </pre>
        </example>
        <para>
          This
        </para>
        <example endspaces=" ">
          <pre xml:space="preserve">
            \DeclareGraphicsRule
Default handler: &lbrace;
            *
Default handler: &rbrace;
Default handler: &lbrace;
            mps
Default handler: &rbrace;
Default handler: &lbrace;
            *
Default handler: &rbrace;
Default handler: &lbrace;
Default handler: &rbrace;
          </pre>
        </example>
        <noindent/>
        <para>
          tells
Default handler: &latex;
           that it should handle as MetaPost output any file with an extension not covered by another rule, so it covers
          <file>
            filename.1
          </file>
          ,
          <file>
            filename.2
          </file>
          , etc.
        </para>
        <para>
          This describes the four arguments.
        </para>
        <table commandarg="var" spaces=" " endspaces=" ">
          <tableentry>
            <tableterm>
              <item spaces=" ">
                <itemformat command="var">
                  extension
                </itemformat>
              </item>
            </tableterm>
            <tableitem>
              <para>
                The file extension to which this rule applies. The extension is anything after and including the first dot in the filename. Use the Kleene star,
                <code>
                  *
                </code>
                , to denote the default behavior for all undeclared extensions.
              </para>
            </tableitem>
          </tableentry>
          <tableentry>
            <tableterm>
              <item spaces=" ">
                <itemformat command="var">
                  type
                </itemformat>
              </item>
            </tableterm>
            <tableitem>
              <para>
                The type of file involved. This type is a string that must be defined in the printer driver. For instance, files with extensions
                <file>
                  .ps
                </file>
                ,
                <file>
                  .eps
                </file>
                , or
                <file>
                  .ps.gz
                </file>
                 may all be classed as type
                <code>
                  eps
                </code>
                . All files of the same type will be input with the same internal command by the printer driver. For example, the file types that
                <file>
                  pdftex
                </file>
                 recognizes are:
                <code>
                  jpg
                </code>
                ,
                <code>
                  jbig2
                </code>
                ,
                <code>
                  mps
                </code>
                ,
                <code>
                  pdf
                </code>
                ,
                <code>
                  png
                </code>
                ,
                <code>
                  tif
                </code>
                .
              </para>
            </tableitem>
          </tableentry>
          <tableentry>
            <tableterm>
              <item spaces=" ">
                <itemformat command="var">
                  size-file extension
                </itemformat>
              </item>
            </tableterm>
            <tableitem>
              <para>
                The extension of the file to be read to determine the size of the graphic, if there is such a file. It may be the same as
                <var>
                  extension
                </var>
                 but it may be different.
              </para>
              <para>
                As an example, consider a PostScript graphic. To make it smaller, it might be compressed into a
                <file>
                  .ps.gz
                </file>
                 file. Compressed files are not easily read by
Default handler: &latex;
                 so you can put the bounding box information in a separate file. If
                <var>
                  size-file extension
                </var>
                 is empty then you must specify size information in the arguments of
                <code>
                  \includegraphics
                </code>
                .
              </para>
              <para>
                If the driver file has a procedure for reading size files for
                <code>
                  type
                </code>
                 then that will be used, otherwise it will use the procedure for reading
                <file>
                  .eps
                </file>
                 files. (Thus you may specify the size of bitmap files in a file with a PostScript style
                <code>
                  %%BoundingBox
                </code>
                 line if no other format is available.)
              </para>
            </tableitem>
          </tableentry>
          <tableentry>
            <tableterm>
              <item spaces=" ">
                <itemformat command="var">
                  command
                </itemformat>
              </item>
            </tableterm>
            <tableitem>
              <para>
                A command that will be applied to the file. This is often left empty. This command must start with a single backward quote. Thus,
                <code>
                  \DeclareGraphicsRule
Default handler: &lbrace;
                  .eps.gz
Default handler: &rbrace;
Default handler: &lbrace;
                  eps
Default handler: &rbrace;
Default handler: &lbrace;
                  .eps.bb
Default handler: &rbrace;
Default handler: &lbrace;
                  `gunzip -c #1
Default handler: &rbrace;
                </code>
                 specifies that any file with the extension
                <file>
                  .eps.gz
                </file>
                 should be treated as an
                <code>
                  eps
                </code>
                 file, with the BoundingBox information stored in the file with extension
                <file>
                  .eps.bb
                </file>
                , and that the command
                <code>
                  gunzip -c
                </code>
                 will run on your platform to decompresses the file.
              </para>
              <para>
                Such a command is specific to your platform. In addition, your
Default handler: &tex;
                 system must allow you to run external commands; as a security measure modern systems restrict running commands unless you explicitly allow it. See the documentation for your
Default handler: &tex;
                 distribution.
              </para>
            </tableitem>
          </tableentry>
        </table>
      </subsection>
    </section>
    <node name="Commands-for-graphics" spaces=" ">
      <nodename>
        Commands for graphics
      </nodename>
      <nodeprev automatic="on">
        Graphics package configuration
      </nodeprev>
      <nodeup automatic="on">
        Graphics
      </nodeup>
    </node>
    <section spaces=" ">
      <sectiontitle>
        Commands for graphics
      </sectiontitle>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="899">
          graphics package commands
        </indexterm>
      </cindex>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="900">
          commands, graphics package
        </indexterm>
      </cindex>
      <para>
        These are the commands available with the
        <code>
          graphics
        </code>
         and
        <code>
          graphicx
        </code>
         packages.
      </para>
      <menu endspaces=" ">
        <menuentry>
          <menuleadingtext>
            *
          </menuleadingtext>
          <menunode>
            \includegraphics
          </menunode>
          <menuseparator>
            ::
          </menuseparator>
          <menudescription>
            <pre xml:space="preserve">
              Using a graphic in your document.
            </pre>
          </menudescription>
        </menuentry>
        <menuentry>
          <menuleadingtext>
            *
          </menuleadingtext>
          <menunode>
            \rotatebox
          </menunode>
          <menuseparator>
            ::
          </menuseparator>
          <menudescription>
            <pre xml:space="preserve">
              Rotating boxes, including graphics.
            </pre>
          </menudescription>
        </menuentry>
        <menuentry>
          <menuleadingtext>
            *
          </menuleadingtext>
          <menunode>
            \scalebox
          </menunode>
          <menuseparator>
            ::
          </menuseparator>
          <menudescription>
            <pre xml:space="preserve">
              Scaling boxes, including graphics.
            </pre>
          </menudescription>
        </menuentry>
        <menuentry>
          <menuleadingtext>
            *
          </menuleadingtext>
          <menunode>
            \resizebox
          </menunode>
          <menuseparator>
            ::
          </menuseparator>
          <menudescription>
            <pre xml:space="preserve">
              Scaling boxes, including graphics, to a set size.
            </pre>
          </menudescription>
        </menuentry>
      </menu>
      <node name="_005cincludegraphics" spaces=" ">
        <nodename>
          \includegraphics
        </nodename>
        <nodenext automatic="on">
          \rotatebox
        </nodenext>
        <nodeup automatic="on">
          Commands for graphics
        </nodeup>
      </node>
      <subsection spaces=" ">
        <sectiontitle>
          <code>
            \includegraphics
          </code>
        </sectiontitle>
        <cindex index="cp" spaces=" ">
          <indexterm index="cp" number="901">
            graphics
          </indexterm>
        </cindex>
        <cindex index="cp" spaces=" ">
          <indexterm index="cp" number="902">
            graphics package
          </indexterm>
        </cindex>
        <cindex index="cp" spaces=" ">
          <indexterm index="cp" number="903">
            including graphics
          </indexterm>
        </cindex>
        <cindex index="cp" spaces=" ">
          <indexterm index="cp" number="904">
            importing graphics
          </indexterm>
        </cindex>
        <cindex index="cp" spaces=" ">
          <indexterm index="cp" number="905">
            EPS files
          </indexterm>
        </cindex>
        <cindex index="cp" spaces=" ">
          <indexterm index="cp" number="906">
            JPEG files
          </indexterm>
        </cindex>
        <cindex index="cp" spaces=" ">
          <indexterm index="cp" number="907">
            JPG files
          </indexterm>
        </cindex>
        <cindex index="cp" spaces=" ">
          <indexterm index="cp" number="908">
            PDF graphic files
          </indexterm>
        </cindex>
        <cindex index="cp" spaces=" ">
          <indexterm index="cp" number="909">
            PNG files
          </indexterm>
        </cindex>
        <findex index="fn" spaces=" ">
          <indexterm index="fn" number="1014" mergedindex="cp">
            \includegraphics
          </indexterm>
        </findex>
        <para>
          Synopses for
          <code>
            graphics
          </code>
           package:
        </para>
        <example endspaces=" ">
          <pre xml:space="preserve">
            \includegraphics
Default handler: &lbrace;
            <var>
              filename
            </var>
Default handler: &rbrace;
             \includegraphics[
            <var>
              urx
            </var>
            ,
            <var>
              ury
            </var>
            ]
Default handler: &lbrace;
            <var>
              filename
            </var>
Default handler: &rbrace;
             \includegraphics[
            <var>
              llx
            </var>
            ,
            <var>
              lly
            </var>
            ][
            <var>
              urx
            </var>
            ,
            <var>
              ury
            </var>
            ]
Default handler: &lbrace;
            <var>
              filename
            </var>
Default handler: &rbrace;
             \includegraphics*
Default handler: &lbrace;
            <var>
              filename
            </var>
Default handler: &rbrace;
             \includegraphics*[
            <var>
              urx
            </var>
            ,
            <var>
              ury
            </var>
            ]
Default handler: &lbrace;
            <var>
              filename
            </var>
Default handler: &rbrace;
             \includegraphics*[
            <var>
              llx
            </var>
            ,
            <var>
              lly
            </var>
            ][
            <var>
              urx
            </var>
            ,
            <var>
              ury
            </var>
            ]
Default handler: &lbrace;
            <var>
              filename
            </var>
Default handler: &rbrace;
          </pre>
        </example>
        <para>
          Synopses for
          <code>
            graphicx
          </code>
           package:
        </para>
        <example endspaces=" ">
          <pre xml:space="preserve">
            \includegraphics
Default handler: &lbrace;
            <var>
              filename
            </var>
Default handler: &rbrace;
             \includegraphics[
            <var>
              key-value list
            </var>
            ]
Default handler: &lbrace;
            <var>
              filename
            </var>
Default handler: &rbrace;
             \includegraphics*
Default handler: &lbrace;
            <var>
              filename
            </var>
Default handler: &rbrace;
             \includegraphics*[
            <var>
              key-value list
            </var>
            ]
Default handler: &lbrace;
            <var>
              filename
            </var>
Default handler: &rbrace;
          </pre>
        </example>
        <para>
          Include a graphics file. The starred form
          <code>
            \includegraphics*
          </code>
           will clip the graphic to the size specified, while for the unstarred form any part of the graphic that is outside the box of the specified size will over-print the surrounding area.
        </para>
        <para>
          This
        </para>
        <example endspaces=" ">
          <pre xml:space="preserve">
            \usepackage
Default handler: &lbrace;
            graphicx
Default handler: &rbrace;
             % in preamble ... \begin
Default handler: &lbrace;
            center
Default handler: &rbrace;
             \includegraphics
Default handler: &lbrace;
            plot.pdf
Default handler: &rbrace;
             \end
Default handler: &lbrace;
            center
Default handler: &rbrace;
          </pre>
        </example>
        <noindent/>
        <para>
          will incorporate into the document the graphic in
          <file>
            plot.pdf
          </file>
          , centered and at its nominal size. You can also give a path to the file, as with
          <code>
            \includegraphics
Default handler: &lbrace;
            graphics/plot.pdf
Default handler: &rbrace;
          </code>
          . To specify a list of locations to search for the file,
          <pxref label="_005cgraphicspath">
            <xrefnodename>
              \graphicspath
            </xrefnodename>
          </pxref>
          .
        </para>
        <para>
          If your filename includes spaces then put it in double quotes. An example is
          <code>
            \includegraphics
Default handler: &lbrace;
            "
            sister picture.jpg
            "
Default handler: &rbrace;
          </code>
          .
        </para>
        <para>
          The
          <code>
            \includegraphics
Default handler: &lbrace;
            <var>
              filename
            </var>
Default handler: &rbrace;
          </code>
           command decides on the type of graphic by splitting
          <var>
            filename
          </var>
           on the first dot. You can instead use
          <var>
            filename
          </var>
           with no dot, as in
          <code>
            \includegraphics
Default handler: &lbrace;
            turing
Default handler: &rbrace;
          </code>
          , and then
Default handler: &latex;
           tries a sequence of extensions such as
          <code>
            .png
          </code>
           and
          <code>
            .pdf
          </code>
           until it finds a file with that extension (
          <pxref label="_005cDeclareGraphicsExtensions">
            <xrefnodename>
              \DeclareGraphicsExtensions
            </xrefnodename>
          </pxref>
          ).
        </para>
        <para>
          If your file name contains dots before the extension then you can hide them with curly braces, as in
          <code>
            \includegraphics
Default handler: &lbrace;
Default handler: &lbrace;
            plot.2018.03.12.a
Default handler: &rbrace;
            .pdf
Default handler: &rbrace;
          </code>
          . Or, if you use the
          <code>
            graphicx
          </code>
           package then you can use the options
          <code>
            type
          </code>
           and
          <code>
            ext
          </code>
          ; see below. This and other filename issues are also handled with the package
          <file>
            grffile
          </file>
          .
        </para>
        <para>
          This example puts a graphic in a
          <code>
            figure
          </code>
           environment so
Default handler: &latex;
           can move it to the next page if fitting it on the current page is awkward (
          <pxref label="figure">
            <xrefnodename>
              figure
            </xrefnodename>
          </pxref>
          ).
        </para>
        <example endspaces=" ">
          <pre xml:space="preserve">
            \begin
Default handler: &lbrace;
            figure
Default handler: &rbrace;
             \centering \includegraphics[width=3cm]
Default handler: &lbrace;
            lungxray.jpg
Default handler: &rbrace;
             \caption
Default handler: &lbrace;
            The evidence is overwhelming: don't smoke.
Default handler: &rbrace;
             \label
Default handler: &lbrace;
            fig:xray
Default handler: &rbrace;
             \end
Default handler: &lbrace;
            figure
Default handler: &rbrace;
          </pre>
        </example>
        <para>
          This places a graphic that will not float, so it is sure to appear at this point in the document even if makes
Default handler: &latex;
           stretch the text or resort to blank areas on the page. It will be centered and will have a caption.
        </para>
        <example endspaces=" ">
          <pre xml:space="preserve">
            \usepackage
Default handler: &lbrace;
            caption
Default handler: &rbrace;
             % in preamble ... \begin
Default handler: &lbrace;
            center
Default handler: &rbrace;
             \includegraphics
Default handler: &lbrace;
            pix/nix.png
Default handler: &rbrace;
             \captionof
Default handler: &lbrace;
            figure
Default handler: &rbrace;
Default handler: &lbrace;
            The spirit of the night
Default handler: &rbrace;
             \label
Default handler: &lbrace;
            pix:nix
Default handler: &rbrace;
             % optional \end
Default handler: &lbrace;
            center
Default handler: &rbrace;
          </pre>
        </example>
        <para>
          This example puts a box with a graphic side by side with one having text, with the two vertically centered.
        </para>
        <example endspaces=" ">
          <pre xml:space="preserve">
            \newcommand*
Default handler: &lbrace;
            \vcenteredhbox
Default handler: &rbrace;
            [1]
Default handler: &lbrace;
            \begin
Default handler: &lbrace;
            tabular
Default handler: &rbrace;
Default handler: &lbrace;
Default handler: &arobase;
Default handler: &lbrace;
Default handler: &rbrace;
            c
Default handler: &arobase;
Default handler: &lbrace;
Default handler: &rbrace;
Default handler: &rbrace;
            #1\end
Default handler: &lbrace;
            tabular
Default handler: &rbrace;
Default handler: &rbrace;
             ... \begin
Default handler: &lbrace;
            center
Default handler: &rbrace;
             \vcenteredhbox
Default handler: &lbrace;
            \includegraphics[width=0.4\textwidth]
Default handler: &lbrace;
            plot
Default handler: &rbrace;
Default handler: &rbrace;
             \hspace
Default handler: &lbrace;
            1em
Default handler: &rbrace;
             \vcenteredhbox
Default handler: &lbrace;
            \begin
Default handler: &lbrace;
            minipage
Default handler: &rbrace;
Default handler: &lbrace;
            0.4\textwidth
Default handler: &rbrace;
             \begin
Default handler: &lbrace;
            displaymath
Default handler: &rbrace;
             f(x)=x\cdot \sin (1/x) \end
Default handler: &lbrace;
            displaymath
Default handler: &rbrace;
             \end
Default handler: &lbrace;
            minipage
Default handler: &rbrace;
Default handler: &rbrace;
             \end
Default handler: &lbrace;
            center
Default handler: &rbrace;
          </pre>
        </example>
        <para>
          If you use the
          <code>
            graphics
          </code>
           package then the only options involve the size of the graphic (but see
          <ref label="_005crotatebox">
            <xrefnodename>
              \rotatebox
            </xrefnodename>
          </ref>
           and
          <ref label="_005cscalebox">
            <xrefnodename>
              \scalebox
            </xrefnodename>
          </ref>
          ). When one optional argument is present then it is
          <code>
            [
            <var>
              urx
            </var>
            ,
            <var>
              ury
            </var>
            ]
          </code>
           and it gives the coordinates of the top right corner of the image, as a pair of
Default handler: &tex;
           dimensions (
          <pxref label="Units-of-length">
            <xrefnodename>
              Units of length
            </xrefnodename>
          </pxref>
          ). If the units are omitted they default to
          <code>
            bp
          </code>
          . In this case, the lower left corner of the image is assumed to be at (0,0). If two optional arguments are present then the leading one is
          <code>
            [
            <var>
              llx
            </var>
            ,
            <var>
              lly
            </var>
            ]
          </code>
          , specifying the coordinates of the image
Default handler: &textrsquo;
          s lower left. Thus,
          <code>
            \includegraphics[1in,0.618in]
Default handler: &lbrace;
            ...
Default handler: &rbrace;
          </code>
           calls for the graphic to be placed so it is 1
Default handler: &nbsp;
          inch wide and 0.618
Default handler: &nbsp;
          inches tall and so its origin is at (0,0).
        </para>
        <para>
          The
          <code>
            graphicx
          </code>
           package gives you many more options. Specify them in a key-value form, as here.
        </para>
        <example endspaces=" ">
          <pre xml:space="preserve">
            \begin
Default handler: &lbrace;
            center
Default handler: &rbrace;
             \includegraphics[width=1in,angle=90]
Default handler: &lbrace;
            lion
Default handler: &rbrace;
             \hspace
Default handler: &lbrace;
            2em
Default handler: &rbrace;
             \includegraphics[angle=90,width=1in]
Default handler: &lbrace;
            lion
Default handler: &rbrace;
             \end
Default handler: &lbrace;
            center
Default handler: &rbrace;
          </pre>
        </example>
        <noindent/>
        <para>
          The options are read left-to-right. So the first graphic above is made one inch wide and then rotated, while the second is rotated and then made one inch wide. Thus, unless the graphic is perfectly square, the two will end with different widths and heights.
        </para>
        <para>
          There are many options. The primary ones are listed first.
        </para>
        <cindex index="cp" spaces=" ">
          <indexterm index="cp" number="910">
            bounding box
          </indexterm>
        </cindex>
        <cindex index="cp" spaces=" ">
          <indexterm index="cp" number="911">
            box, bounding
          </indexterm>
        </cindex>
        <para>
          Note that a graphic is placed by
Default handler: &latex;
           into a box, which is traditionally referred to as its
          <dfn>
            bounding box
          </dfn>
           (distinct from the PostScript BoundingBox described below). The graphic
Default handler: &textrsquo;
          s printed area may go beyond this box, or sit inside this box, but when
Default handler: &latex;
           makes up a page it puts together boxes and this is the box allocated for the graphic.
        </para>
        <table commandarg="code" spaces=" " endspaces=" ">
          <beforefirstitem>
            <anchor name="includegraphics-width">
              includegraphics width
            </anchor>
          </beforefirstitem>
          <tableentry>
            <tableterm>
              <item spaces=" ">
                <itemformat command="code">
                  width
                </itemformat>
              </item>
            </tableterm>
            <tableitem>
              <para>
                The graphic will be shown so its bounding box is this width. An example is
                <code>
                  \includegraphics[width=1in]
Default handler: &lbrace;
                  plot
Default handler: &rbrace;
                </code>
                . You can use the standard
Default handler: &tex;
                 dimensions (
                <pxref label="Units-of-length">
                  <xrefnodename>
                    Units of length
                  </xrefnodename>
                </pxref>
                ) and also convenient is
                <code>
                  \linewidth
                </code>
                , or in a two-column document,
                <code>
                  \columnwidth
                </code>
                 (
                <pxref label="Page-layout-parameters">
                  <xrefnodename>
                    Page layout parameters
                  </xrefnodename>
                </pxref>
                ). An example is that by using the
                <file>
                  calc
                </file>
                 package you can make the graphic be 1
Default handler: &nbsp;
                cm narrower than the width of the text with
                <code>
                  \includegraphics[width=\linewidth-1.0cm]
Default handler: &lbrace;
                  hefferon.jpg
Default handler: &rbrace;
                </code>
                .
              </para>
            </tableitem>
          </tableentry>
          <tableentry>
            <tableterm>
              <item spaces=" ">
                <itemformat command="code">
                  height
                </itemformat>
              </item>
            </tableterm>
            <tableitem>
              <anchor name="includegraphics-height">
                includegraphics height
              </anchor>
              <para>
                The graphic will be shown so its bounding box is this height. You can use the standard
Default handler: &tex;
                 dimensions (
                <pxref label="Units-of-length">
                  <xrefnodename>
                    Units of length
                  </xrefnodename>
                </pxref>
                ), and also convenient are
                <code>
                  \pageheight
                </code>
                 and
                <code>
                  \textheight
                </code>
                 (
                <pxref label="Page-layout-parameters">
                  <xrefnodename>
                    Page layout parameters
                  </xrefnodename>
                </pxref>
                ). For instance, the command
                <code>
                  \includegraphics[height=0.25\textheight]
Default handler: &lbrace;
                  godel
Default handler: &rbrace;
                </code>
                 will make the graphic a quarter of the height of the text area.
              </para>
            </tableitem>
          </tableentry>
          <tableentry>
            <tableterm>
              <item spaces=" ">
                <itemformat command="code">
                  totalheight
                </itemformat>
              </item>
            </tableterm>
            <tableitem>
              <anchor name="includegraphics-totalheight">
                includegraphics totalheight
              </anchor>
              <para>
                The graphic will be shown so its bounding box has this height plus depth. This differs from the height if the graphic was rotated. For instance, if it has been rotated by -90 then it will have zero height but a large depth.
              </para>
            </tableitem>
          </tableentry>
          <tableentry>
            <tableterm>
              <item spaces=" ">
                <itemformat command="code">
                  keepaspectratio
                </itemformat>
              </item>
            </tableterm>
            <tableitem>
              <anchor name="includegraphics-keepaspectratio">
                includegraphics keepaspectratio
              </anchor>
              <para>
                If set to
                <code>
                  true
                </code>
                , or just specified as here
              </para>
              <example endspaces=" ">
                <pre xml:space="preserve">
                  <code>
                    \includegraphics[...,keepaspectratio,...]
Default handler: &lbrace;
                    ...
Default handler: &rbrace;
                  </code>
                </pre>
              </example>
              <noindent/>
              <para>
                and you give as options both
                <code>
                  width
                </code>
                 and
                <code>
                  height
                </code>
                 (or
                <code>
                  totalheight
                </code>
                ), then
Default handler: &latex;
                 will make the graphic is as large as possible without distortion. That is,
Default handler: &latex;
                 will ensure that neither is the graphic wider than
                <code>
                  width
                </code>
                 nor taller than
                <code>
                  height
                </code>
                 (or
                <code>
                  totalheight
                </code>
                ).
              </para>
            </tableitem>
          </tableentry>
          <tableentry>
            <tableterm>
              <item spaces=" ">
                <itemformat command="code">
                  scale
                </itemformat>
              </item>
            </tableterm>
            <tableitem>
              <para>
                Factor by which to scale the graphic. To make a graphic twice its nominal size, enter
                <code>
                  \includegraphics[scale=2.0]
Default handler: &lbrace;
                  ...
Default handler: &rbrace;
                </code>
                . This number may be any value; a number between 0 and
Default handler: &nbsp;
                1 will shrink the graphic and a negative number will reflect it.
              </para>
            </tableitem>
          </tableentry>
          <tableentry>
            <tableterm>
              <item spaces=" ">
                <itemformat command="code">
                  angle
                </itemformat>
              </item>
            </tableterm>
            <tableitem>
              <para>
                Rotate the graphic. The angle is taken in degrees and counterclockwise. The graphic is rotated about its
                <code>
                  origin
                </code>
                ; see that option. For a complete description of how rotated material is typeset,
                <pxref label="_005crotatebox">
                  <xrefnodename>
                    \rotatebox
                  </xrefnodename>
                </pxref>
                .
              </para>
            </tableitem>
          </tableentry>
          <tableentry>
            <tableterm>
              <item spaces=" ">
                <itemformat command="code">
                  origin
                </itemformat>
              </item>
            </tableterm>
            <tableitem>
              <para>
                The point of the graphic about which the rotation happens. Possible values are any string containing one or two of:
                <code>
                  l
                </code>
                 for left,
                <code>
                  r
                </code>
                 for right,
                <code>
                  b
                </code>
                 for bottom,
                <code>
                  c
                </code>
                 for center,
                <code>
                  t
                </code>
                 for top, and
                <code>
                  B
                </code>
                 for baseline. Thus, entering the command
                <code>
                  \includegraphics[angle=180,origin=c]
Default handler: &lbrace;
                  moon
Default handler: &rbrace;
                </code>
                 will turn the picture upside down about that picture
Default handler: &textrsquo;
                s center, while the command
                <code>
                  \includegraphics[angle=180,origin=lB]
Default handler: &lbrace;
                  LeBateau
Default handler: &rbrace;
                </code>
                 will turn its picture upside down about its left baseline. (The character
                <code>
                  c
                </code>
                 gives the horizontal center in
                <code>
                  bc
                </code>
                 or
                <code>
                  tc
                </code>
                , but gives the vertical center in
                <code>
                  lc
                </code>
                 or
                <code>
                  rc
                </code>
                .) The default is
                <code>
                  lB
                </code>
                .
              </para>
              <para>
                To rotate about an arbitrary point,
                <pxref label="_005crotatebox">
                  <xrefnodename>
                    \rotatebox
                  </xrefnodename>
                </pxref>
                .
              </para>
            </tableitem>
          </tableentry>
        </table>
        <para>
          These are lesser-used options.
        </para>
        <table commandarg="code" spaces=" " endspaces=" ">
          <beforefirstitem>
            <anchor name="includegraphics-viewport">
              includegraphics viewport
            </anchor>
          </beforefirstitem>
          <tableentry>
            <tableterm>
              <item spaces=" ">
                <itemformat command="code">
                  viewport
                </itemformat>
              </item>
            </tableterm>
            <tableitem>
              <para>
                Pick out a subregion of the graphic to show. Takes four arguments, separated by spaces and given in
Default handler: &tex;
                 dimensions, as with
                <code>
                  \includegraphics[.., viewport=0in 0in 1in 0.618in]
Default handler: &lbrace;
                  ...
Default handler: &rbrace;
                </code>
                . When the unit is omitted, the dimensions default to big points,
Default handler: &nbsp;
                <code>
                  bp
                </code>
                . They are taken relative to the origin specified by the bounding box. See also the
                <code>
                  trim
                </code>
                 option.
              </para>
              <anchor name="includegraphics-trim">
                includegraphics trim
              </anchor>
            </tableitem>
          </tableentry>
          <tableentry>
            <tableterm>
              <item spaces=" ">
                <itemformat command="code">
                  trim
                </itemformat>
              </item>
            </tableterm>
            <tableitem>
              <para>
                Gives parts of the graphic to not show. Takes four arguments, separated by spaces, that are given in
Default handler: &tex;
                 dimensions, as with
                <code>
                  \includegraphics[.., trim= 0in 0.1in 0.2in 0.3in, ...]
Default handler: &lbrace;
                  ...
Default handler: &rbrace;
                </code>
                . These give the amounts of the graphic not to show, that is,
Default handler: &latex;
                 will crop the picture by 0
Default handler: &nbsp;
                inches on the left, 0.1
Default handler: &nbsp;
                inches on the bottom, 0.2
Default handler: &nbsp;
                inches on the right, and 0.3
Default handler: &nbsp;
                inches on the top. See also the
                <code>
                  viewport
                </code>
                 option.
              </para>
              <anchor name="includegraphics-clip">
                includegraphics clip
              </anchor>
            </tableitem>
          </tableentry>
          <tableentry>
            <tableterm>
              <item spaces=" ">
                <itemformat command="code">
                  clip
                </itemformat>
              </item>
            </tableterm>
            <tableitem>
              <para>
                If set to
                <code>
                  true
                </code>
                , or just specified as here
              </para>
              <example endspaces=" ">
                <pre xml:space="preserve">
                  \includegraphics[...,clip,...]
Default handler: &lbrace;
                  ...
Default handler: &rbrace;
                </pre>
              </example>
              <noindent/>
              <para>
                then the graphic is cropped to the bounding box. This is the same as using the starred form of the command,
                <code>
                  \includegraphics*[...]
Default handler: &lbrace;
                  ...
Default handler: &rbrace;
                </code>
                .
              </para>
              <anchor name="includegraphics-page">
                includegraphics page
              </anchor>
            </tableitem>
          </tableentry>
          <tableentry>
            <tableterm>
              <item spaces=" ">
                <itemformat command="code">
                  page
                </itemformat>
              </item>
            </tableterm>
            <tableitem>
              <para>
                Give the page number of a multi-page PDF file. The default is
                <code>
                  page=1
                </code>
                .
              </para>
              <anchor name="includegraphics-pagebox">
                includegraphics pagebox
              </anchor>
            </tableitem>
          </tableentry>
          <tableentry>
            <tableterm>
              <item spaces=" ">
                <itemformat command="code">
                  pagebox
                </itemformat>
              </item>
            </tableterm>
            <tableitem>
              <para>
                Specifies which bounding box to use for PDF files from among
                <code>
                  mediabox
                </code>
                ,
                <code>
                  cropbox
                </code>
                ,
                <code>
                  bleedbox
                </code>
                ,
                <code>
                  trimbox
                </code>
                , or
                <code>
                  artbox
                </code>
                . PDF files do not have the BoundingBox that PostScript files have, but may specify up to four predefined rectangles. The MediaBox gives the boundaries of the physical medium. The CropBox is the region to which the contents of the page are to be clipped when displayed. The BleedBox is the region to which the contents of the page should be clipped in production. The TrimBox is the intended dimensions of the finished page. The ArtBox is the extent of the page
Default handler: &textrsquo;
                s meaningful content. The driver will set the image size based on CropBox if present, otherwise it will not use one of the others, with a driver-defined order of preference. MediaBox is always present.
              </para>
              <anchor name="includegraphics-interpolate">
                includegraphics interpolate
              </anchor>
            </tableitem>
          </tableentry>
          <tableentry>
            <tableterm>
              <item spaces=" ">
                <itemformat command="code">
                  interpolate
                </itemformat>
              </item>
            </tableterm>
            <tableitem>
              <para>
                Enable or disable interpolation of raster images by the viewer. Can be set with
                <code>
                  interpolate=true
                </code>
                 or just specified as here.
              </para>
              <example endspaces=" ">
                <pre xml:space="preserve">
                  \includegraphics[...,interpolate,...]
Default handler: &lbrace;
                  ...
Default handler: &rbrace;
                </pre>
              </example>
              <anchor name="includegraphics-quiet">
                includegraphics quiet
              </anchor>
            </tableitem>
          </tableentry>
          <tableentry>
            <tableterm>
              <item spaces=" ">
                <itemformat command="code">
                  quiet
                </itemformat>
              </item>
            </tableterm>
            <tableitem>
              <para>
                Do not write information to the log. You can set it with
                <code>
                  quiet=true
                </code>
                 or just specified it with
                <code>
                  \includegraphics[...,quiet,...]
Default handler: &lbrace;
                  ...
Default handler: &rbrace;
                </code>
                ,
              </para>
              <anchor name="includegraphics-draft">
                includegraphics draft
              </anchor>
            </tableitem>
          </tableentry>
          <tableentry>
            <tableterm>
              <item spaces=" ">
                <itemformat command="code">
                  draft
                </itemformat>
              </item>
            </tableterm>
            <tableitem>
              <para>
                If you set it with
                <code>
                  draft=true
                </code>
                 or just specify it with
              </para>
              <example endspaces=" ">
                <pre xml:space="preserve">
                  \includegraphics[...,draft,...]
Default handler: &lbrace;
                  ...
Default handler: &rbrace;
                </pre>
              </example>
              <noindent/>
              <para>
                then the graphic will not appear in the document, possibly saving color printer ink. Instead,
Default handler: &latex;
                 will put an empty box of the correct size with the filename printed in it.
              </para>
            </tableitem>
          </tableentry>
        </table>
        <para>
          These options address the bounding box for Encapsulated PostScript graphic files, which have a size specified with a line
          <code>
            %%BoundingBox
          </code>
           that appears in the file. It has four values, giving the lower
          <math>
            x
          </math>
           coordinate, lower
          <math>
            y
          </math>
           coordinate, upper
          <math>
            x
          </math>
           coordinate, and upper
          <math>
            y
          </math>
           coordinate. The units are PostScript points, equivalent to
Default handler: &tex;
Default handler: &textrsquo;
          s big points, 1/72
Default handler: &nbsp;
          inch. For example, if an
          <file>
            .eps
          </file>
           file has the line
          <code>
            %%BoundingBox 10 20 40 80
          </code>
           then its natural size is 30/72
Default handler: &nbsp;
          inch wide by 60/72
Default handler: &nbsp;
          inch tall.
        </para>
        <table commandarg="code" spaces=" " endspaces=" ">
          <beforefirstitem>
            <anchor name="includegraphics-bb">
              includegraphics bb
            </anchor>
          </beforefirstitem>
          <tableentry>
            <tableterm>
              <item spaces=" ">
                <itemformat command="code">
                  bb
                </itemformat>
              </item>
            </tableterm>
            <tableitem>
              <para>
                Specify the bounding box of the displayed region. The argument is four dimensions separated by spaces, as with
                <code>
                  \includegraphics[.., bb= 0in 0in 1in 0.618in]
Default handler: &lbrace;
                  ...
Default handler: &rbrace;
                </code>
                . Usually
                <code>
                  \includegraphics
                </code>
                 reads the BoundingBox numbers from the EPS file automatically, so this option is only useful if the bounding box is missing from that file or if you want to change it.
              </para>
              <anchor name="includegraphics-bbllx">
                includegraphics bbllx
              </anchor>
              <anchor name="includegraphics-bblly">
                includegraphics bblly
              </anchor>
              <anchor name="includegraphics-bburx">
                includegraphics bburx
              </anchor>
              <anchor name="includegraphics-bbury">
                includegraphics bbury
              </anchor>
            </tableitem>
          </tableentry>
          <tableentry>
            <tableterm>
              <item spaces=" ">
                <itemformat command="code">
                  bbllx, bblly, bburx, bbury
                </itemformat>
              </item>
            </tableterm>
            <tableitem>
              <para>
                Set the bounding box. These four are obsolete, but are retained for compatibility with old packages.
              </para>
              <anchor name="includegraphics-natwidth">
                includegraphics natwidth
              </anchor>
              <anchor name="includegraphics-natheight">
                includegraphics natheight
              </anchor>
            </tableitem>
          </tableentry>
          <tableentry>
            <tableterm>
              <item spaces=" ">
                <itemformat command="code">
                  natwidth, natheight
                </itemformat>
              </item>
            </tableterm>
            <tableitem>
              <para>
                An alternative for
                <code>
                  bb
                </code>
                . Setting
              </para>
              <example endspaces=" ">
                <pre xml:space="preserve">
                  \includegraphics[...,natwidth=1in,natheight=0.618in,...]
Default handler: &lbrace;
                  ...
Default handler: &rbrace;
                </pre>
              </example>
              <noindent/>
              <para>
                is the same as setting
                <code>
                  bb=0 0 1in 0.618in
                </code>
                .
              </para>
              <anchor name="includegraphics-hiresbb">
                includegraphics hiresbb
              </anchor>
            </tableitem>
          </tableentry>
          <tableentry>
            <tableterm>
              <item spaces=" ">
                <itemformat command="code">
                  hiresbb
                </itemformat>
              </item>
            </tableterm>
            <tableitem>
              <para>
                If set to
                <code>
                  true
                </code>
                , or just specified as with
              </para>
              <example endspaces=" ">
                <pre xml:space="preserve">
                  \includegraphics[...,hiresbb,...]
Default handler: &lbrace;
                  ...
Default handler: &rbrace;
                </pre>
              </example>
              <noindent/>
              <para>
                then
Default handler: &latex;
                 will look for
                <code>
                  %%HiResBoundingBox
                </code>
                 lines instead of
                <code>
                  %%BoundingBox
                </code>
                 lines. (The
                <code>
                  BoundingBox
                </code>
                 lines use only natural numbers while the
                <code>
                  HiResBoundingBox
                </code>
                 lines use decimals; both use units equivalent to
Default handler: &tex;
Default handler: &textrsquo;
                s big points, 1/72
Default handler: &nbsp;
                inch.) To override a prior setting of
                <code>
                  true
                </code>
                , you can set it to
                <code>
                  false
                </code>
                .
              </para>
            </tableitem>
          </tableentry>
        </table>
        <para>
          These following options allow a user to override
Default handler: &latex;
Default handler: &textrsquo;
          s method of choosing the graphic type based on the filename extension. An example is that
          <code>
            \includegraphics[type=png,ext=.xyz,read=.xyz]
Default handler: &lbrace;
            lion
Default handler: &rbrace;
          </code>
           will read the file
          <file>
            lion.xyz
          </file>
           as though it were
          <file>
            lion.png
          </file>
          . For more on these,
          <pxref label="_005cDeclareGraphicsRule">
            <xrefnodename>
              \DeclareGraphicsRule
            </xrefnodename>
          </pxref>
          .
        </para>
        <table commandarg="code" spaces=" " endspaces=" ">
          <beforefirstitem>
            <anchor name="includegraphics-type">
              includegraphics type
            </anchor>
          </beforefirstitem>
          <tableentry>
            <tableterm>
              <item spaces=" ">
                <itemformat command="code">
                  type
                </itemformat>
              </item>
            </tableterm>
            <tableitem>
              <para>
                Specify the graphics type.
              </para>
              <anchor name="includegraphics-ext">
                includegraphics ext
              </anchor>
            </tableitem>
          </tableentry>
          <tableentry>
            <tableterm>
              <item spaces=" ">
                <itemformat command="code">
                  ext
                </itemformat>
              </item>
            </tableterm>
            <tableitem>
              <para>
                Specify the graphics extension. Only use this in conjunction with the option
                <code>
                  type
                </code>
                .
              </para>
              <anchor name="includegraphics-read">
                includegraphics read
              </anchor>
            </tableitem>
          </tableentry>
          <tableentry>
            <tableterm>
              <item spaces=" ">
                <itemformat command="code">
                  read
                </itemformat>
              </item>
            </tableterm>
            <tableitem>
              <para>
                Specify the file extension of the read file. Only use this in conjunction with the option
                <code>
                  type
                </code>
                .
              </para>
              <anchor name="includegraphics-command">
                includegraphics command
              </anchor>
            </tableitem>
          </tableentry>
          <tableentry>
            <tableterm>
              <item spaces=" ">
                <itemformat command="code">
                  command
                </itemformat>
              </item>
            </tableterm>
            <tableitem>
              <para>
                Specify a command to be applied to this file. Only use this in conjunction with the option
                <code>
                  type
                </code>
                .
                <xref label="Command-line-options">
                  <xrefnodename>
                    Command line options
                  </xrefnodename>
                </xref>
                , for a discussion of enabling the
                <code>
                  \write18
                </code>
                 functionality to run external commands.
              </para>
            </tableitem>
          </tableentry>
        </table>
      </subsection>
      <node name="_005crotatebox" spaces=" ">
        <nodename>
          \rotatebox
        </nodename>
        <nodenext automatic="on">
          \scalebox
        </nodenext>
        <nodeprev automatic="on">
          \includegraphics
        </nodeprev>
        <nodeup automatic="on">
          Commands for graphics
        </nodeup>
      </node>
      <subsection spaces=" ">
        <sectiontitle>
          <code>
            \rotatebox
          </code>
        </sectiontitle>
        <cindex index="cp" spaces=" ">
          <indexterm index="cp" number="912">
            rotation
          </indexterm>
        </cindex>
        <cindex index="cp" spaces=" ">
          <indexterm index="cp" number="913">
            rotating graphics
          </indexterm>
        </cindex>
        <cindex index="cp" spaces=" ">
          <indexterm index="cp" number="914">
            rotating text
          </indexterm>
        </cindex>
        <findex index="fn" spaces=" ">
          <indexterm index="fn" number="1015" mergedindex="cp">
            \rotatebox
          </indexterm>
        </findex>
        <para>
          Synopsis if you use the
          <code>
            graphics
          </code>
           package:
        </para>
        <example endspaces=" ">
          <pre xml:space="preserve">
            \rotatebox
Default handler: &lbrace;
            <var>
              angle
            </var>
Default handler: &rbrace;
Default handler: &lbrace;
            <var>
              material
            </var>
Default handler: &rbrace;
          </pre>
        </example>
        <para>
          Synopses if you use the
          <code>
            graphicx
          </code>
           package:
        </para>
        <example endspaces=" ">
          <pre xml:space="preserve">
            \rotatebox
Default handler: &lbrace;
            <var>
              angle
            </var>
Default handler: &rbrace;
Default handler: &lbrace;
            <var>
              material
            </var>
Default handler: &rbrace;
             \rotatebox[
            <var>
              key-value list
            </var>
            ]
Default handler: &lbrace;
            <var>
              angle
            </var>
Default handler: &rbrace;
Default handler: &lbrace;
            <var>
              material
            </var>
Default handler: &rbrace;
          </pre>
        </example>
        <para>
          Put
          <var>
            material
          </var>
           in a box and rotate it
          <var>
            angle
          </var>
           degrees counterclockwise.
        </para>
        <para>
          This example rotates the table column heads forty-five degrees.
        </para>
        <example endspaces=" ">
          <pre xml:space="preserve">
            \begin
Default handler: &lbrace;
            tabular
Default handler: &rbrace;
Default handler: &lbrace;
            ll
Default handler: &rbrace;
             \rotatebox
Default handler: &lbrace;
            45
Default handler: &rbrace;
Default handler: &lbrace;
            Character
Default handler: &rbrace;
            &
            \rotatebox
Default handler: &lbrace;
            45
Default handler: &rbrace;
Default handler: &lbrace;
            NATO phonetic
Default handler: &rbrace;
             \\ A
            &
            AL-FAH \\ B
            &
            BRAH-VOH \end
Default handler: &lbrace;
            tabular
Default handler: &rbrace;
          </pre>
        </example>
        <para>
          The
          <var>
            material
          </var>
           can be anything that goes in a box, including a graphic.
        </para>
        <example endspaces=" ">
          <pre xml:space="preserve">
             \rotatebox[origin=c]
Default handler: &lbrace;
            45
Default handler: &rbrace;
Default handler: &lbrace;
            \includegraphics[width=1in]
Default handler: &lbrace;
            lion
Default handler: &rbrace;
Default handler: &rbrace;
          </pre>
        </example>
        <para>
          To place the rotated material, the first step is that
Default handler: &latex;
           sets
          <var>
            material
          </var>
           in a box, with a reference point on the left baseline. The second step is the rotation, by default about the reference point. The third step is that
Default handler: &latex;
           computes a box to bound the rotated material. Fourth,
Default handler: &latex;
           moves this box horizontally so that the left edge of this new bounding box coincides with the left edge of the box from the first step (they need not coincide vertically). This new bounding box, in its new position, is what
Default handler: &latex;
           uses as the box when typesetting this material.
        </para>
        <para>
          If you use the
          <code>
            graphics
          </code>
           package then the rotation is about the reference point of the box. If you use the
          <code>
            graphicx
          </code>
           package then these are the options that can go in the
          <var>
            key-value list
          </var>
          , but note that you can get the same effect without needing this package, except for the
          <code>
            x
          </code>
           and
          <code>
            y
          </code>
           options (
          <pxref label="_005cincludegraphics">
            <xrefnodename>
              \includegraphics
            </xrefnodename>
          </pxref>
          ).
        </para>
        <table commandarg="code" spaces=" " endspaces=" ">
          <tableentry>
            <tableterm>
              <item spaces=" ">
                <itemformat command="code">
                  origin
                </itemformat>
              </item>
            </tableterm>
            <tableitem>
              <para>
                The point of the
                <var>
                  material
                </var>
Default handler: &textrsquo;
                s box about which the rotation happens. Possible value is any string containing one or two of:
                <code>
                  l
                </code>
                 for left,
                <code>
                  r
                </code>
                 for right,
                <code>
                  b
                </code>
                 for bottom,
                <code>
                  c
                </code>
                 for center,
                <code>
                  t
                </code>
                 for top, and
                <code>
                  B
                </code>
                 for baseline. Thus, the first line here
              </para>
              <example endspaces=" ">
                <pre xml:space="preserve">
                  \rotatebox[origin=c]
Default handler: &lbrace;
                  180
Default handler: &rbrace;
Default handler: &lbrace;
                  moon
Default handler: &rbrace;
                   \rotatebox[origin=lB]
Default handler: &lbrace;
                  180
Default handler: &rbrace;
Default handler: &lbrace;
                  LeBateau
Default handler: &rbrace;
                </pre>
              </example>
              <noindent/>
              <para>
                will turn the picture upside down from the center while the second will turn its picture upside down about its left baseline. (The character
                <code>
                  c
                </code>
                 gives the horizontal center in
                <code>
                  bc
                </code>
                 or
                <code>
                  tc
                </code>
                 but gives the vertical center in
                <code>
                  lc
                </code>
                 or
                <code>
                  rc
                </code>
                , and gives both in
                <code>
                  c
                </code>
                .) The default is
                <code>
                  lB
                </code>
                .
              </para>
            </tableitem>
          </tableentry>
          <tableentry>
            <tableterm>
              <item spaces=" ">
                <itemformat command="code">
                  x, y
                </itemformat>
              </item>
            </tableterm>
            <tableitem>
              <para>
                Specify an arbitrary point of rotation with
                <code>
                  \rotatebox[x=
                  <varDefault handler: &tex;
>
                     dimension
                  </var>
                  ,y=
                  <varDefault handler: &tex;
>
                     dimension
                  </var>
                  ]
Default handler: &lbrace;
                  ...
Default handler: &rbrace;
                </code>
                 (
                <pxref label="Units-of-length">
                  <xrefnodename>
                    Units of length
                  </xrefnodename>
                </pxref>
                ). These give the offset from the box
Default handler: &textrsquo;
                s reference point.
              </para>
            </tableitem>
          </tableentry>
          <tableentry>
            <tableterm>
              <item spaces=" ">
                <itemformat command="code">
                  units
                </itemformat>
              </item>
            </tableterm>
            <tableitem>
              <para>
                This key allows you to change the default of degrees counterclockwise. Setting
                <code>
                  units=-360
                </code>
                 changes the direction to degrees clockwise and setting
                <code>
                  units=6.283185
                </code>
                 changes to radians counterclockwise.
              </para>
            </tableitem>
          </tableentry>
        </table>
      </subsection>
      <node name="_005cscalebox" spaces=" ">
        <nodename>
          \scalebox
        </nodename>
        <nodenext automatic="on">
          \resizebox
        </nodenext>
        <nodeprev automatic="on">
          \rotatebox
        </nodeprev>
        <nodeup automatic="on">
          Commands for graphics
        </nodeup>
      </node>
      <subsection spaces=" ">
        <sectiontitle>
          <code>
            \scalebox
          </code>
        </sectiontitle>
        <cindex index="cp" spaces=" ">
          <indexterm index="cp" number="915">
            graphics, scaling
          </indexterm>
        </cindex>
        <cindex index="cp" spaces=" ">
          <indexterm index="cp" number="916">
            graphics, resizing
          </indexterm>
        </cindex>
        <cindex index="cp" spaces=" ">
          <indexterm index="cp" number="917">
            scaling
          </indexterm>
        </cindex>
        <cindex index="cp" spaces=" ">
          <indexterm index="cp" number="918">
            resizing
          </indexterm>
        </cindex>
        <cindex index="cp" spaces=" ">
          <indexterm index="cp" number="919">
            text, scaling
          </indexterm>
        </cindex>
        <cindex index="cp" spaces=" ">
          <indexterm index="cp" number="920">
            text, resizing
          </indexterm>
        </cindex>
        <findex index="fn" spaces=" ">
          <indexterm index="fn" number="1016" mergedindex="cp">
            \scalebox
          </indexterm>
        </findex>
        <findex index="fn" spaces=" ">
          <indexterm index="fn" number="1017" mergedindex="cp">
            \reflectbox
          </indexterm>
        </findex>
        <para>
          Synopses:
        </para>
        <example endspaces=" ">
          <pre xml:space="preserve">
            \scalebox
Default handler: &lbrace;
            <var>
              horizontal factor
            </var>
Default handler: &rbrace;
Default handler: &lbrace;
            <var>
              material
            </var>
Default handler: &rbrace;
             \scalebox
Default handler: &lbrace;
            <var>
              horizontal factor
            </var>
Default handler: &rbrace;
            [
            <var>
              vertical factor
            </var>
            ]
Default handler: &lbrace;
            <var>
              material
            </var>
Default handler: &rbrace;
             \reflectbox
Default handler: &lbrace;
            <var>
              material
            </var>
Default handler: &rbrace;
          </pre>
        </example>
        <para>
          Scale the
          <var>
            material
          </var>
          .
        </para>
        <para>
          This example halves the size, both horizontally and vertically, of the first text and doubles the size of the second.
        </para>
        <example endspaces=" ">
          <pre xml:space="preserve">
            \scalebox
Default handler: &lbrace;
            0.5
Default handler: &rbrace;
Default handler: &lbrace;
            DRINK ME
Default handler: &rbrace;
             and \scalebox
Default handler: &lbrace;
            2.0
Default handler: &rbrace;
Default handler: &lbrace;
            Eat Me
Default handler: &rbrace;
          </pre>
        </example>
        <para>
          If you do not specify the optional
          <var>
            vertical factor
          </var>
           then it defaults to the same value as the
          <var>
            horizontal factor
          </var>
          .
        </para>
        <para>
          You can use this command to resize a graphic, as here.
        </para>
        <example endspaces=" ">
          <pre xml:space="preserve">
            \scalebox
Default handler: &lbrace;
            0.5
Default handler: &rbrace;
Default handler: &lbrace;
            \includegraphics
Default handler: &lbrace;
            lion
Default handler: &rbrace;
Default handler: &rbrace;
          </pre>
        </example>
        <noindent/>
        <para>
          If you use the
          <code>
            graphicx
          </code>
           package then you can accomplish the same thing with optional arguments to
          <code>
            \includegraphics
          </code>
           (
          <pxref label="_005cincludegraphics">
            <xrefnodename>
              \includegraphics
            </xrefnodename>
          </pxref>
          ).
        </para>
        <para>
          The
          <code>
            \reflectbox
          </code>
           command abbreviates
          <code>
            \scalebox
Default handler: &lbrace;
            -1
Default handler: &rbrace;
            [1]
Default handler: &lbrace;
            <var>
              material
            </var>
Default handler: &rbrace;
          </code>
          . Thus,
          <code>
            Able was I\reflectbox
Default handler: &lbrace;
            Able was I
Default handler: &rbrace;
          </code>
           will show the phrase
          <samp>
            Able was I
          </samp>
           immediately followed by its mirror reflection against a vertical axis.
        </para>
      </subsection>
      <node name="_005cresizebox" spaces=" ">
        <nodename>
          \resizebox
        </nodename>
        <nodeprev automatic="on">
          \scalebox
        </nodeprev>
        <nodeup automatic="on">
          Commands for graphics
        </nodeup>
      </node>
      <subsection spaces=" ">
        <sectiontitle>
          <code>
            \resizebox
          </code>
        </sectiontitle>
        <cindex index="cp" spaces=" ">
          <indexterm index="cp" number="921">
            graphics, scaling
          </indexterm>
        </cindex>
        <cindex index="cp" spaces=" ">
          <indexterm index="cp" number="922">
            graphics, resizing
          </indexterm>
        </cindex>
        <cindex index="cp" spaces=" ">
          <indexterm index="cp" number="923">
            scaling
          </indexterm>
        </cindex>
        <cindex index="cp" spaces=" ">
          <indexterm index="cp" number="924">
            resizing
          </indexterm>
        </cindex>
        <cindex index="cp" spaces=" ">
          <indexterm index="cp" number="925">
            text, scaling
          </indexterm>
        </cindex>
        <cindex index="cp" spaces=" ">
          <indexterm index="cp" number="926">
            text, resizing
          </indexterm>
        </cindex>
        <findex index="fn" spaces=" ">
          <indexterm index="fn" number="1018" mergedindex="cp">
            \resizebox
          </indexterm>
        </findex>
        <para>
          Synopses:
        </para>
        <example endspaces=" ">
          <pre xml:space="preserve">
            \resizebox
Default handler: &lbrace;
            <var>
              horizontal length
            </var>
Default handler: &rbrace;
Default handler: &lbrace;
            <var>
              vertical length
            </var>
Default handler: &rbrace;
Default handler: &lbrace;
            <var>
              material
            </var>
Default handler: &rbrace;
             \resizebox*
Default handler: &lbrace;
            <var>
              horizontal length
            </var>
Default handler: &rbrace;
Default handler: &lbrace;
            <var>
              vertical length
            </var>
Default handler: &rbrace;
Default handler: &lbrace;
            <var>
              material
            </var>
Default handler: &rbrace;
          </pre>
        </example>
        <para>
          Given a size, such as
          <code>
            3cm
          </code>
          , transform
          <var>
            material
          </var>
           to make it that size. If either
          <var>
            horizontal length
          </var>
           or
          <var>
            vertical length
          </var>
           is an exclamation point
Default handler: &nbsp;
          <code>
            !
          </code>
           then the other argument is used to determine a scale factor for both directions.
        </para>
        <para>
          This example makes the graphic be a half inch wide and scales it vertically by the same factor to keep it from being distorted.
        </para>
        <example endspaces=" ">
          <pre xml:space="preserve">
            \resizebox
Default handler: &lbrace;
            0.5in
Default handler: &rbrace;
Default handler: &lbrace;
            !
Default handler: &rbrace;
Default handler: &lbrace;
            \includegraphics
Default handler: &lbrace;
            lion
Default handler: &rbrace;
Default handler: &rbrace;
          </pre>
        </example>
        <para>
          The unstarred form
          <code>
            \resizebox
          </code>
           takes
          <var>
            vertical length
          </var>
           to be the box
Default handler: &textrsquo;
          s height while the starred form
          <code>
            \resizebox*
          </code>
           takes it to be height+depth. For instance, make the text have a height+depth of a quarter-inch with
          <code>
            \resizebox*
Default handler: &lbrace;
            !
Default handler: &rbrace;
Default handler: &lbrace;
            0.25in
Default handler: &rbrace;
Default handler: &lbrace;
            \parbox
Default handler: &lbrace;
            3.5in
Default handler: &rbrace;
Default handler: &lbrace;
            This box has both height and depth.
Default handler: &rbrace;
Default handler: &rbrace;
          </code>
          .
        </para>
        <para>
          You can use
          <code>
            \depth
          </code>
          ,
          <code>
            \height
          </code>
          ,
          <code>
            \totalheight
          </code>
          , and
          <code>
            \width
          </code>
           to refer to the original size of the box. Thus, make the text two inches wide but keep the original height with
          <code>
            \resizebox
Default handler: &lbrace;
            2in
Default handler: &rbrace;
Default handler: &lbrace;
            \height
Default handler: &rbrace;
Default handler: &lbrace;
            Two inches
Default handler: &rbrace;
          </code>
          .
        </para>
      </subsection>
    </section>
  </chapter>
  <node name="Color" spaces=" ">
    <nodename>
      Color
    </nodename>
    <nodenext automatic="on">
      Special insertions
    </nodenext>
    <nodeprev automatic="on">
      Graphics
    </nodeprev>
    <nodeup automatic="on">
      Top
    </nodeup>
  </node>
  <chapter spaces=" ">
    <sectiontitle>
      Color
    </sectiontitle>
    <cindex index="cp" spaces=" ">
      <indexterm index="cp" number="927">
        color
      </indexterm>
    </cindex>
    <para>
      You can add color to text, rules, etc. You can also have color in a box or on an entire page and write text on top of it.
    </para>
    <para>
      Color support comes as an additional package. So put
      <code>
        \usepackage
Default handler: &lbrace;
        color
Default handler: &rbrace;
      </code>
       in your document preamble to use the commands described here.
    </para>
    <para>
      Many other packages also supplement
Default handler: &latex;
Default handler: &textrsquo;
      s color abilities. Particularly worth mentioning is
      <file>
        xcolor
      </file>
      , which is widely used and significantly extends the capabilities described here, including adding
      <samp>
        HTML
      </samp>
       and
      <samp>
        Hsb
      </samp>
       color models.
    </para>
    <menu endspaces=" ">
      <menuentry>
        <menuleadingtext>
          *
        </menuleadingtext>
        <menunode>
          Color package options
        </menunode>
        <menuseparator>
          ::
        </menuseparator>
        <menudescription>
          <pre xml:space="preserve">
            Options when you load the standard package.
          </pre>
        </menudescription>
      </menuentry>
      <menuentry>
        <menuleadingtext>
          *
        </menuleadingtext>
        <menunode>
          Color models
        </menunode>
        <menuseparator>
          ::
        </menuseparator>
        <menudescription>
          <pre xml:space="preserve">
            How colors are represented.
          </pre>
        </menudescription>
      </menuentry>
      <menuentry>
        <menuleadingtext>
          *
        </menuleadingtext>
        <menunode>
          Commands for color
        </menunode>
        <menuseparator>
          ::
        </menuseparator>
        <menudescription>
          <pre xml:space="preserve">
            The available commands.
          </pre>
        </menudescription>
      </menuentry>
    </menu>
    <node name="Color-package-options" spaces=" ">
      <nodename>
        Color package options
      </nodename>
      <nodenext automatic="on">
        Color models
      </nodenext>
      <nodeup automatic="on">
        Color
      </nodeup>
    </node>
    <section spaces=" ">
      <sectiontitle>
        <code>
          color
        </code>
         package options
      </sectiontitle>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="928">
          color package options
        </indexterm>
      </cindex>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="929">
          options, color package
        </indexterm>
      </cindex>
      <para>
        Synopsis (must be in the document preamble):
      </para>
      <example endspaces=" ">
        <pre xml:space="preserve">
          \usepackage[
          <var>
            comma-separated option list
          </var>
          ]
Default handler: &lbrace;
          color
Default handler: &rbrace;
        </pre>
      </example>
      <para>
        When you load the
        <file>
          color
        </file>
         package there are two kinds of available options.
      </para>
      <para>
        The first specifies the
        <dfn>
          printer driver
        </dfn>
        .
Default handler: &latex;
         doesn
Default handler: &textrsquo;
        t contain information about different output systems but instead depends on information stored in a file. Normally you should not specify the driver option in the document, and instead rely on your system
Default handler: &textrsquo;
        s default. One advantage of this is that it makes the document portable across systems. For completeness we include a list of the drivers. The currently relevant ones are:
        <file>
          dvipdfmx
        </file>
        ,
        <file>
          dvips
        </file>
        ,
        <file>
          dvisvgm
        </file>
        ,
        <file>
          luatex
        </file>
        ,
        <file>
          pdftex
        </file>
        ,
        <file>
          xetex
        </file>
        . The two
        <file>
          xdvi
        </file>
         and
        <file>
          oztex
        </file>
         are essentially aliases for
        <file>
          dvips
        </file>
         (and
        <file>
          xdvi
        </file>
         is monochrome). Ones that should not be used for new systems are:
        <file>
          dvipdf
        </file>
        ,
        <file>
          dvipdfm
        </file>
        ,
        <file>
          dviwin
        </file>
        ,
        <file>
          dvipsone
        </file>
        ,
        <file>
          emtex
        </file>
        ,
        <file>
          pctexps
        </file>
        ,
        <file>
          pctexwin
        </file>
        ,
        <file>
          pctexhp
        </file>
        ,
        <file>
          pctex32
        </file>
        ,
        <file>
          truetex
        </file>
        ,
        <file>
          tcidvi
        </file>
        ,
        <file>
          vtex
        </file>
         (and
        <file>
          dviwindo
        </file>
         is an alias for
        <file>
          dvipsone
        </file>
        ).
      </para>
      <para>
        The second kind of options, beyond the drivers, are below.
      </para>
      <table commandarg="code" spaces=" " endspaces=" ">
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                monochrome
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <para>
              Disable the color commands, so that they do not generate errors but do not generate color either.
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                dvipsnames
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <para>
              Make available a list of 68 color names that are often used, particularly in legacy documents. These color names were originally provided by the
              <file>
                dvips
              </file>
               driver, giving the option name.
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                nodvipsnames
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <para>
              Do not load that list of color names, saving
Default handler: &latex;
               a tiny amount of memory space.
            </para>
          </tableitem>
        </tableentry>
      </table>
    </section>
    <node name="Color-models" spaces=" ">
      <nodename>
        Color models
      </nodename>
      <nodenext automatic="on">
        Commands for color
      </nodenext>
      <nodeprev automatic="on">
        Color package options
      </nodeprev>
      <nodeup automatic="on">
        Color
      </nodeup>
    </node>
    <section spaces=" ">
      <sectiontitle>
        Color models
      </sectiontitle>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="930">
          color models
        </indexterm>
      </cindex>
      <para>
        A
        <dfn>
          color model
        </dfn>
         is a way of representing colors.
Default handler: &latex;
Default handler: &textrsquo;
        s capabilities depend on the printer driver. However, the
        <file>
          pdftex
        </file>
        ,
        <file>
          xetex
        </file>
        , and
        <file>
          luatex
        </file>
         printer drivers are today by far the most commonly used. The models below work for those drivers. All but one of these is also supported by essentially all other printer drivers used today.
      </para>
      <para>
        Note that color combination can be additive or subtractive. Additive mixes colors of light, so that for instance combining full intensities of red, green, and blue produces white. Subtractive mixes pigments, such as with inks, so that combining full intensity of cyan, magenta, and yellow makes black.
      </para>
      <table commandarg="code" spaces=" " endspaces=" ">
        <beforefirstitem>
          <anchor name="color-models-cmyk">
            color models cmyk
          </anchor>
        </beforefirstitem>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                cmyk
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <para>
              A comma-separated list with four real numbers between 0 and 1, inclusive. The first number is the intensity of cyan, the second is magenta, and the others are yellow and black. A number value of 0 means minimal intensity, while a 1 is for full intensity. This model is often used in color printing. It is a subtractive model.
            </para>
            <anchor name="color-models-gray">
              color models gray
            </anchor>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                gray
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <para>
              A single real number between 0 and 1, inclusive. The colors are shades of grey. The number 0 produces black while 1 gives white.
            </para>
            <anchor name="color-models-rgb">
              color models rgb
            </anchor>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                rgb
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <para>
              A comma-separated list with three real numbers between 0 and 1, inclusive. The first number is the intensity of the red component, the second is green, and the third the blue. A number value of 0 means that none of that component is added in, while a 1 means full intensity. This is an additive model.
            </para>
            <anchor name="color-models-RGB">
              color models RGB
            </anchor>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                RGB
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <para>
              (
              <file>
                pdftex
              </file>
              ,
              <file>
                xetex
              </file>
              ,
              <file>
                luatex
              </file>
               drivers) A comma-separated list with three integers between 0 and 255, inclusive. This model is a convenience for using
              <code>
                rgb
              </code>
               since outside of
Default handler: &latex;
               colors are often described in a red-green-blue model using numbers in this range. The values entered here are converted to the
              <code>
                rgb
              </code>
               model by dividing by 255.
            </para>
            <anchor name="color-models-named">
              color models named
            </anchor>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                named
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <para>
              Colors are accessed by name, such as
              <samp>
                PrussianBlue
              </samp>
              . The list of names depends on the driver, but all support the names
              <samp>
                black
              </samp>
              ,
              <samp>
                blue
              </samp>
              ,
              <samp>
                cyan
              </samp>
              ,
              <samp>
                green
              </samp>
              ,
              <samp>
                magenta
              </samp>
              ,
              <samp>
                red
              </samp>
              ,
              <samp>
                white
              </samp>
              , and
              <samp>
                yellow
              </samp>
               (See the
              <code>
                dvipsnames
              </code>
               option in
              <ref label="Color-package-options">
                <xrefnodename>
                  Color package options
                </xrefnodename>
              </ref>
              ).
            </para>
          </tableitem>
        </tableentry>
      </table>
    </section>
    <node name="Commands-for-color" spaces=" ">
      <nodename>
        Commands for color
      </nodename>
      <nodeprev automatic="on">
        Color models
      </nodeprev>
      <nodeup automatic="on">
        Color
      </nodeup>
    </node>
    <section spaces=" ">
      <sectiontitle>
        Commands for color
      </sectiontitle>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="931">
          color package commands
        </indexterm>
      </cindex>
      <para>
        These are the commands available with the
        <file>
          color
        </file>
         package.
      </para>
      <menu endspaces=" ">
        <menuentry>
          <menuleadingtext>
            *
          </menuleadingtext>
          <menunode>
            Define colors
          </menunode>
          <menuseparator>
            ::
          </menuseparator>
          <menudescription>
            <pre xml:space="preserve">
              Give a color a name.
            </pre>
          </menudescription>
        </menuentry>
        <menuentry>
          <menuleadingtext>
            *
          </menuleadingtext>
          <menunode>
            Colored text
          </menunode>
          <menuseparator>
            ::
          </menuseparator>
          <menudescription>
            <pre xml:space="preserve">
              Text or rules in color.
            </pre>
          </menudescription>
        </menuentry>
        <menuentry>
          <menuleadingtext>
            *
          </menuleadingtext>
          <menunode>
            Colored boxes
          </menunode>
          <menuseparator>
            ::
          </menuseparator>
          <menudescription>
            <pre xml:space="preserve">
              A box of color, to write over.
            </pre>
          </menudescription>
        </menuentry>
        <menuentry>
          <menuleadingtext>
            *
          </menuleadingtext>
          <menunode>
            Colored pages
          </menunode>
          <menuseparator>
            ::
          </menuseparator>
          <menudescription>
            <pre xml:space="preserve">
              A whole page colored.
            </pre>
          </menudescription>
        </menuentry>
      </menu>
      <node name="Define-colors" spaces=" ">
        <nodename>
          Define colors
        </nodename>
        <nodenext automatic="on">
          Colored text
        </nodenext>
        <nodeup automatic="on">
          Commands for color
        </nodeup>
      </node>
      <subsection spaces=" ">
        <sectiontitle>
          Define colors
        </sectiontitle>
        <cindex index="cp" spaces=" ">
          <indexterm index="cp" number="932">
            color
          </indexterm>
        </cindex>
        <cindex index="cp" spaces=" ">
          <indexterm index="cp" number="933">
            define color
          </indexterm>
        </cindex>
        <cindex index="cp" spaces=" ">
          <indexterm index="cp" number="934">
            color, define
          </indexterm>
        </cindex>
        <para>
          Synopsis:
        </para>
        <example endspaces=" ">
          <pre xml:space="preserve">
            \definecolor
Default handler: &lbrace;
            <var>
              name
            </var>
Default handler: &rbrace;
Default handler: &lbrace;
            <var>
              model
            </var>
Default handler: &rbrace;
Default handler: &lbrace;
            <var>
              specification
            </var>
Default handler: &rbrace;
          </pre>
        </example>
        <para>
          Give the name
          <var>
            name
          </var>
           to the color. For example, after this
        </para>
        <example endspaces=" ">
          <pre xml:space="preserve">
            \definecolor
Default handler: &lbrace;
            silver
Default handler: &rbrace;
Default handler: &lbrace;
            rgb
Default handler: &rbrace;
Default handler: &lbrace;
            0.75,0.75,0.74
Default handler: &rbrace;
          </pre>
        </example>
        <noindent/>
        <para>
          you can use that color name with
          <code>
            Hi ho, \textcolor
Default handler: &lbrace;
            silver
Default handler: &rbrace;
Default handler: &lbrace;
            Silver
Default handler: &rbrace;
            !
          </code>
          .
        </para>
        <para>
          This example gives the color a more abstract name, so it could change and not be misleading.
        </para>
        <example endspaces=" ">
          <pre xml:space="preserve">
            \definecolor
Default handler: &lbrace;
            logocolor
Default handler: &rbrace;
Default handler: &lbrace;
            RGB
Default handler: &rbrace;
Default handler: &lbrace;
            145,92,131
Default handler: &rbrace;
             % RGB needs pdflatex \newcommand
Default handler: &lbrace;
            \logo
Default handler: &rbrace;
Default handler: &lbrace;
            \textcolor
Default handler: &lbrace;
            logocolor
Default handler: &rbrace;
Default handler: &lbrace;
            Bob's Big Bagels
Default handler: &rbrace;
Default handler: &rbrace;
          </pre>
        </example>
        <para>
          Often a document
Default handler: &textrsquo;
          s colors are defined in the preamble, or in the class or style, rather than in the document body.
        </para>
      </subsection>
      <node name="Colored-text" spaces=" ">
        <nodename>
          Colored text
        </nodename>
        <nodenext automatic="on">
          Colored boxes
        </nodenext>
        <nodeprev automatic="on">
          Define colors
        </nodeprev>
        <nodeup automatic="on">
          Commands for color
        </nodeup>
      </node>
      <subsection spaces=" ">
        <sectiontitle>
          Colored text
        </sectiontitle>
        <cindex index="cp" spaces=" ">
          <indexterm index="cp" number="935">
            color
          </indexterm>
        </cindex>
        <cindex index="cp" spaces=" ">
          <indexterm index="cp" number="936">
            colored text
          </indexterm>
        </cindex>
        <para>
          Synopses:
        </para>
        <example endspaces=" ">
          <pre xml:space="preserve">
            \textcolor
Default handler: &lbrace;
            <var>
              name
            </var>
Default handler: &rbrace;
Default handler: &lbrace;
            ...
Default handler: &rbrace;
             \textcolor[
            <var>
              color model
            </var>
            ]
Default handler: &lbrace;
            <var>
              color specification
            </var>
Default handler: &rbrace;
Default handler: &lbrace;
            ...
Default handler: &rbrace;
          </pre>
        </example>
        <noindent/>
        <para>
          or
        </para>
        <example endspaces=" ">
          <pre xml:space="preserve">
            \color
Default handler: &lbrace;
            <var>
              name
            </var>
Default handler: &rbrace;
             \color[
            <var>
              color model
            </var>
            ]
Default handler: &lbrace;
            <var>
              color specification
            </var>
Default handler: &rbrace;
          </pre>
        </example>
        <para>
          The affected text gets the color. This line
        </para>
        <example endspaces=" ">
          <pre xml:space="preserve">
            \textcolor
Default handler: &lbrace;
            magenta
Default handler: &rbrace;
Default handler: &lbrace;
            My name is Ozymandias, King of Kings;
Default handler: &rbrace;
             Look on my works, ye Mighty, and despair!
          </pre>
        </example>
        <noindent/>
        <para>
          causes the first half to be in magenta while the rest is in black. You can use a color declared with
          <code>
            \definecolor
          </code>
           in exactly the same way that we just used the builtin color
          <samp>
            magenta
          </samp>
          .
        </para>
        <example endspaces=" ">
          <pre xml:space="preserve">
            \definecolor
Default handler: &lbrace;
            MidlifeCrisisRed
Default handler: &rbrace;
Default handler: &lbrace;
            rgb
Default handler: &rbrace;
Default handler: &lbrace;
            1.0,0.11,0.0
Default handler: &rbrace;
             I'm thinking about getting a \textcolor
Default handler: &lbrace;
            MidlifeCrisisRed
Default handler: &rbrace;
Default handler: &lbrace;
            sports car
Default handler: &rbrace;
            .
          </pre>
        </example>
        <para>
          The two
          <code>
            \textcolor
          </code>
           and
          <code>
            \color
          </code>
           differ in that the first is a command form, enclosing the text to be colored as an argument. Often this form is more convenient, or at least more explicit. The second form is a declaration, as in
          <code>
            The moon is made of
Default handler: &lbrace;
            \color
Default handler: &lbrace;
            green
Default handler: &rbrace;
             green
Default handler: &rbrace;
             cheese
          </code>
          , so it is in effect until the end of the current group or environment. This is sometimes useful when writing macros or as below where it colors everything inside the
          <code>
            center
          </code>
           environment, including the vertical and horizontal lines.
        </para>
        <example endspaces=" ">
          <pre xml:space="preserve">
            \begin
Default handler: &lbrace;
            center
Default handler: &rbrace;
             \color
Default handler: &lbrace;
            blue
Default handler: &rbrace;
             \begin
Default handler: &lbrace;
            tabular
Default handler: &rbrace;
Default handler: &lbrace;
            l|r
Default handler: &rbrace;
             UL
            &
            UR \\ \hline LL
            &
            LR \end
Default handler: &lbrace;
            tabular
Default handler: &rbrace;
             \end
Default handler: &lbrace;
            center
Default handler: &rbrace;
          </pre>
        </example>
        <para>
          You can use color in equations. A document might have this definition in the preamble
        </para>
        <example endspaces=" ">
          <pre xml:space="preserve">
            \definecolor
Default handler: &lbrace;
            highlightcolor
Default handler: &rbrace;
Default handler: &lbrace;
            RGB
Default handler: &rbrace;
Default handler: &lbrace;
            225,15,0
Default handler: &rbrace;
          </pre>
        </example>
        <noindent/>
        <para>
          and then contain this equation.
        </para>
        <example endspaces=" ">
          <pre xml:space="preserve">
            \begin
Default handler: &lbrace;
            equation
Default handler: &rbrace;
             \int_a^b \textcolor
Default handler: &lbrace;
            highlightcolor
Default handler: &rbrace;
Default handler: &lbrace;
            f'(x)
Default handler: &rbrace;
            \,dx=f(b)-f(a) \end
Default handler: &lbrace;
            equation
Default handler: &rbrace;
          </pre>
        </example>
        <para>
          Typically the colors used in a document are declared in a class or style but sometimes you want a one-off. Those are the second forms in the synopses.
        </para>
        <example endspaces=" ">
          <pre xml:space="preserve">
            Colors of \textcolor[rgb]
Default handler: &lbrace;
            0.33,0.14,0.47
Default handler: &rbrace;
Default handler: &lbrace;
            Purple
Default handler: &rbrace;
             and
Default handler: &lbrace;
            \color[rgb]
Default handler: &lbrace;
            0.72,0.60,0.37
Default handler: &rbrace;
            Gold
Default handler: &rbrace;
             for the team.
          </pre>
        </example>
        <para>
          The format of
          <var>
            color specification
          </var>
           depends on the color model (
          <pxref label="Color-models">
            <xrefnodename>
              Color models
            </xrefnodename>
          </pxref>
          ). For instance, while
          <code>
            rgb
          </code>
           takes three numbers,
          <code>
            gray
          </code>
           takes only one.
        </para>
        <example endspaces=" ">
          <pre xml:space="preserve">
            The selection was \textcolor[gray]
Default handler: &lbrace;
            0.5
Default handler: &rbrace;
Default handler: &lbrace;
            grayed out
Default handler: &rbrace;
            .
          </pre>
        </example>
        <para>
          Colors inside colors do not combine. Thus
        </para>
        <example endspaces=" ">
          <pre xml:space="preserve">
            \textcolor
Default handler: &lbrace;
            green
Default handler: &rbrace;
Default handler: &lbrace;
            kind of \textcolor
Default handler: &lbrace;
            blue
Default handler: &rbrace;
Default handler: &lbrace;
            blue
Default handler: &rbrace;
Default handler: &rbrace;
          </pre>
        </example>
        <noindent/>
        <para>
          has a final word that is blue, not a combination of blue and green.
        </para>
Default handler: <!-- c xx address coloring a line of a table? -->
      </subsection>
      <node name="Colored-boxes" spaces=" ">
        <nodename>
          Colored boxes
        </nodename>
        <nodenext automatic="on">
          Colored pages
        </nodenext>
        <nodeprev automatic="on">
          Colored text
        </nodeprev>
        <nodeup automatic="on">
          Commands for color
        </nodeup>
      </node>
      <subsection spaces=" ">
        <sectiontitle>
          Colored boxes
        </sectiontitle>
        <cindex index="cp" spaces=" ">
          <indexterm index="cp" number="937">
            color
          </indexterm>
        </cindex>
        <cindex index="cp" spaces=" ">
          <indexterm index="cp" number="938">
            colored boxes
          </indexterm>
        </cindex>
        <cindex index="cp" spaces=" ">
          <indexterm index="cp" number="939">
            box, colored
          </indexterm>
        </cindex>
        <para>
          Synopses:
        </para>
        <example endspaces=" ">
          <pre xml:space="preserve">
            \colorbox
Default handler: &lbrace;
            <var>
              name
            </var>
Default handler: &rbrace;
Default handler: &lbrace;
            ...
Default handler: &rbrace;
             \colorbox[
            <var>
              model name
            </var>
            ]
Default handler: &lbrace;
            <var>
              box background color
            </var>
Default handler: &rbrace;
Default handler: &lbrace;
            ...
Default handler: &rbrace;
          </pre>
        </example>
        <noindent/>
        <para>
          or
        </para>
        <example endspaces=" ">
          <pre xml:space="preserve">
            \fcolorbox
Default handler: &lbrace;
            <var>
              frame color
            </var>
Default handler: &rbrace;
Default handler: &lbrace;
            <var>
              box background color
            </var>
Default handler: &rbrace;
Default handler: &lbrace;
            ...
Default handler: &rbrace;
             \fcolorbox[
            <var>
              model name
            </var>
            ]
Default handler: &lbrace;
            <var>
              frame color
            </var>
Default handler: &rbrace;
Default handler: &lbrace;
            <var>
              box background color
            </var>
Default handler: &rbrace;
Default handler: &lbrace;
            ...
Default handler: &rbrace;
          </pre>
        </example>
        <para>
          Make a box with the stated background color. The
          <code>
            \fcolorbox
          </code>
           command puts a frame around the box. For instance this
        </para>
        <example endspaces=" ">
          <pre xml:space="preserve">
            Name:~\colorbox
Default handler: &lbrace;
            cyan
Default handler: &rbrace;
Default handler: &lbrace;
            \makebox[5cm][l]
Default handler: &lbrace;
            \strut
Default handler: &rbrace;
Default handler: &rbrace;
          </pre>
        </example>
        <noindent/>
        <para>
          makes a cyan-colored box that is five centimeters long and gets its depth and height from the
          <code>
            \strut
          </code>
           (so the depth is
          <code>
            -.3\baselineskip
          </code>
           and the height is
          <code>
            \baselineskip
          </code>
          ). This puts white text on a blue background.
        </para>
        <example endspaces=" ">
          <pre xml:space="preserve">
            \colorbox
Default handler: &lbrace;
            blue
Default handler: &rbrace;
Default handler: &lbrace;
            \textcolor
Default handler: &lbrace;
            white
Default handler: &rbrace;
Default handler: &lbrace;
            Welcome to the machine.
Default handler: &rbrace;
Default handler: &rbrace;
          </pre>
        </example>
        <para>
          The
          <code>
            \fcolorbox
          </code>
           commands use the same parameters as
          <code>
            \fbox
          </code>
           (
          <pxref label="_005cfbox-_0026-_005cframebox">
            <xrefnodename>
              \fbox
              &
               \framebox
            </xrefnodename>
          </pxref>
          ),
          <code>
            \fboxrule
          </code>
           and
          <code>
            \fboxsep
          </code>
          , to set the thickness of the rule and the boundary between the box interior and the surrounding rule.
Default handler: &latex;
Default handler: &textrsquo;
          s defaults are
          <code>
            0.4pt
          </code>
           and
          <code>
            3pt
          </code>
          , respectively.
        </para>
        <para>
          This example changes the thickness of the border to 0.8 points. Note that it is surrounded by curly braces so that the change ends at the end of the second line.
        </para>
        <example endspaces=" ">
          <pre xml:space="preserve"Default handler: &lbrace;
>
            \setlength
Default handler: &lbrace;
            \fboxrule
Default handler: &rbrace;
Default handler: &lbrace;
            0.8pt
Default handler: &rbrace;
             \fcolorbox
Default handler: &lbrace;
            black
Default handler: &rbrace;
Default handler: &lbrace;
            red
Default handler: &rbrace;
Default handler: &lbrace;
            Under no circumstances turn this knob.
Default handler: &rbrace;
Default handler: &rbrace;
          </pre>
        </example>
      </subsection>
      <node name="Colored-pages" spaces=" ">
        <nodename>
          Colored pages
        </nodename>
        <nodeprev automatic="on">
          Colored boxes
        </nodeprev>
        <nodeup automatic="on">
          Commands for color
        </nodeup>
      </node>
      <subsection spaces=" ">
        <sectiontitle>
          Colored pages
        </sectiontitle>
        <cindex index="cp" spaces=" ">
          <indexterm index="cp" number="940">
            color
          </indexterm>
        </cindex>
        <cindex index="cp" spaces=" ">
          <indexterm index="cp" number="941">
            colored page
          </indexterm>
        </cindex>
        <cindex index="cp" spaces=" ">
          <indexterm index="cp" number="942">
            page, colored
          </indexterm>
        </cindex>
        <cindex index="cp" spaces=" ">
          <indexterm index="cp" number="943">
            background, colored
          </indexterm>
        </cindex>
        <para>
          Synopses:
        </para>
        <example endspaces=" ">
          <pre xml:space="preserve">
            \pagecolor
Default handler: &lbrace;
            <var>
              name
            </var>
Default handler: &rbrace;
             \pagecolor[
            <var>
              color model
            </var>
            ]
Default handler: &lbrace;
            <var>
              color specification
            </var>
Default handler: &rbrace;
             \nopagecolor
          </pre>
        </example>
        <para>
          The first two set the background of the page, and all subsequent pages, to the color. For an explanation of the specification in the second form
          <pxref label="Colored-text">
            <xrefnodename>
              Colored text
            </xrefnodename>
          </pxref>
          . The third returns the background to normal, which is a transparent background. (If that is not supported use
          <code>
            \pagecolor
Default handler: &lbrace;
            white
Default handler: &rbrace;
          </code>
          , although that will make a white background rather than the default transparent background.)
        </para>
        <example endspaces=" ">
          <pre xml:space="preserve">
             ... \pagecolor
Default handler: &lbrace;
            cyan
Default handler: &rbrace;
             ... \nopagecolor
          </pre>
        </example>
      </subsection>
    </section>
  </chapter>
  <node name="Special-insertions" spaces=" ">
    <nodename>
      Special insertions
    </nodename>
    <nodenext automatic="on">
      Splitting the input
    </nodenext>
    <nodeprev automatic="on">
      Color
    </nodeprev>
    <nodeup automatic="on">
      Top
    </nodeup>
  </node>
  <chapter spaces=" ">
    <sectiontitle>
      Special insertions
    </sectiontitle>
    <cindex index="cp" spaces=" ">
      <indexterm index="cp" number="944">
        special insertions
      </indexterm>
    </cindex>
    <cindex index="cp" spaces=" ">
      <indexterm index="cp" number="945">
        insertions of special characters
      </indexterm>
    </cindex>
    <paraDefault handler: &latex;
>
       provides commands for inserting characters that have a special meaning do not correspond to simple characters you can type.
    </para>
    <menu endspaces=" ">
      <menuentry>
        <menuleadingtext>
          *
        </menuleadingtext>
        <menunode>
          Printing special characters
        </menunode>
        <menuseparator>
          ::
        </menuseparator>
        <menudescription>
          <pre xml:space="preserve">
            Inserting
            <samp>
              # $ %
              &
Default handler: &lbrace;
Default handler: &rbrace;
               _ ~ ^ \
            </samp>
          </pre>
        </menudescription>
      </menuentry>
      <menuentry>
        <menuleadingtext>
          *
        </menuleadingtext>
        <menunode>
          Upper and lower case
        </menunode>
        <menuseparator>
          ::
        </menuseparator>
        <menudescription>
          <pre xml:space="preserve">
            Make text upper or lower case.
          </pre>
        </menudescription>
      </menuentry>
      <menuentry>
        <menuleadingtext>
          *
        </menuleadingtext>
        <menunode>
          Symbols by font position
        </menunode>
        <menuseparator>
          ::
        </menuseparator>
        <menudescription>
          <pre xml:space="preserve">
            Inserting font symbols by number.
          </pre>
        </menudescription>
      </menuentry>
      <menuentry>
        <menuleadingtext>
          *
        </menuleadingtext>
        <menunode>
          Text symbols
        </menunode>
        <menuseparator>
          ::
        </menuseparator>
        <menudescription>
          <pre xml:space="preserve">
            Inserting other non-letter symbols in text.
          </pre>
        </menudescription>
      </menuentry>
      <menuentry>
        <menuleadingtext>
          *
        </menuleadingtext>
        <menunode>
          Accents
        </menunode>
        <menuseparator>
          ::
        </menuseparator>
        <menudescription>
          <pre xml:space="preserve">
            Inserting accents.
          </pre>
        </menudescription>
      </menuentry>
      <menuentry>
        <menuleadingtext>
          *
        </menuleadingtext>
        <menunode>
          Additional Latin letters
        </menunode>
        <menuseparator>
          ::
        </menuseparator>
        <menudescription>
          <pre xml:space="preserve">
            Inserting other non-English characters.
          </pre>
        </menudescription>
      </menuentry>
      <menuentry>
        <menuleadingtext>
          *
        </menuleadingtext>
        <menunode>
          inputenc package
        </menunode>
        <menuseparator>
          ::
        </menuseparator>
        <menudescription>
          <pre xml:space="preserve">
            Set the input file text encoding.
          </pre>
        </menudescription>
      </menuentry>
      <menuentry>
        <menuleadingtext>
          *
        </menuleadingtext>
        <menunode>
          \rule
        </menunode>
        <menuseparator>
          ::
        </menuseparator>
        <menudescription>
          <pre xml:space="preserve">
            Inserting lines and rectangles.
          </pre>
        </menudescription>
      </menuentry>
      <menuentry>
        <menuleadingtext>
          *
        </menuleadingtext>
        <menunode>
          \today
        </menunode>
        <menuseparator>
          ::
        </menuseparator>
        <menudescription>
          <pre xml:space="preserve">
            Inserting today
Default handler: &textrsquo;
            s date.
          </pre>
        </menudescription>
      </menuentry>
    </menu>
    <node name="Printing-special-characters" spaces=" ">
      <nodename>
        Printing special characters
      </nodename>
      <nodenext automatic="on">
        Upper and lower case
      </nodenext>
      <nodeup automatic="on">
        Special insertions
      </nodeup>
    </node>
    <section spaces=" ">
      <sectiontitle>
        Printing special characters
      </sectiontitle>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="946">
          reserved characters, printing
        </indexterm>
      </cindex>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="947">
          special characters, printing
        </indexterm>
      </cindex>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="948">
          printing special characters
        </indexterm>
      </cindex>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="949">
          escaping special characters
        </indexterm>
      </cindex>
      <paraDefault handler: &latex;
>
         sets aside a few characters for special purposes; they are called reserved characters or special characters. Here they are:
      </para>
      <example endspaces=" ">
        <pre xml:space="preserve">
          # $ %
          &
Default handler: &lbrace;
Default handler: &rbrace;
           _ ~ ^ \
        </pre>
      </example>
      <para>
        The meaning of all the special characters is given elsewhere in this manual (
        <pxref label="Reserved-characters">
          <xrefnodename>
            Reserved characters
          </xrefnodename>
        </pxref>
        ).
      </para>
      <findex index="fn" spaces=" ">
        <indexterm index="fn" number="1019" mergedindex="cp">
          \#
        </indexterm>
      </findex>
      <findex index="fn" spaces=" ">
        <indexterm index="fn" number="1020" mergedindex="cp">
          \$
        </indexterm>
      </findex>
      <findex index="fn" spaces=" ">
        <indexterm index="fn" number="1021" mergedindex="cp">
          \%
        </indexterm>
      </findex>
      <findex index="fn" spaces=" ">
        <indexterm index="fn" number="1022" mergedindex="cp">
          \
          &
        </indexterm>
      </findex>
      <findex index="fn" spaces=" ">
        <indexterm index="fn" number="1023" mergedindex="cp">
          \_
        </indexterm>
      </findex>
      <findex index="fn" spaces=" ">
        <indexterm index="fn" number="1024" mergedindex="cp">
          \
Default handler: &lbrace;
        </indexterm>
      </findex>
      <findex index="fn" spaces=" ">
        <indexterm index="fn" number="1025" mergedindex="cp">
          \
Default handler: &rbrace;
        </indexterm>
      </findex>
      <para>
        If you want a reserved character to be printed as itself, in the text body font, for all but the final three characters in that list simply put a
        <code>
          \
        </code>
         in front of the character. Thus, typing
        <code>
          \$1.23
        </code>
         will produce
        <code>
          $1.23
        </code>
         in your output.
      </para>
      <findex index="fn" spaces=" ">
        <indexterm index="fn" number="1026" mergedindex="cp">
          \~
        </indexterm>
      </findex>
      <findex index="fn" spaces=" ">
        <indexterm index="fn" number="1027" mergedindex="cp">
          \^
        </indexterm>
      </findex>
      <findex index="fn" spaces=" ">
        <indexterm index="fn" number="1028" mergedindex="cp">
          \textbackslash
        </indexterm>
      </findex>
      <para>
        As to the last three characters, to get a tilde in the text body font use
        <code>
          \~
Default handler: &lbrace;
Default handler: &rbrace;
        </code>
         (omitting the curly braces would result in the next character receiving a tilde accent). Similarly, to get a text body font circumflex use
        <code>
          \^
Default handler: &lbrace;
Default handler: &rbrace;
        </code>
        . To get a backslash in the font of the text body, enter
        <code>
          \textbackslash
Default handler: &lbrace;
Default handler: &rbrace;
        </code>
        .
      </para>
      <para>
        To produce the reserved characters in a typewriter font, use
        <code>
          \verb!!
        </code>
         as below (the
        <code>
          \newline
        </code>
         in the example is there only to split the lines in the output).
      </para>
      <example endspaces=" ">
        <pre xml:space="preserve">
          \begin
Default handler: &lbrace;
          center
Default handler: &rbrace;
           \# \$ \% \
          &
           \
Default handler: &lbrace;
           \
Default handler: &rbrace;
           \_ \~
Default handler: &lbrace;
Default handler: &rbrace;
           \^
Default handler: &lbrace;
Default handler: &rbrace;
           \textbackslash \newline \verb!# $ %
          &
Default handler: &lbrace;
Default handler: &rbrace;
           _ ~ ^ \! \end
Default handler: &lbrace;
          center
Default handler: &rbrace;
        </pre>
      </example>
    </section>
    <node name="Upper-and-lower-case" spaces=" ">
      <nodename>
        Upper and lower case
      </nodename>
      <nodenext automatic="on">
        Symbols by font position
      </nodenext>
      <nodeprev automatic="on">
        Printing special characters
      </nodeprev>
      <nodeup automatic="on">
        Special insertions
      </nodeup>
    </node>
    <section spaces=" ">
      <sectiontitle>
        Upper and lower case
      </sectiontitle>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="950">
          uppercase
        </indexterm>
      </cindex>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="951">
          lowercase
        </indexterm>
      </cindex>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="952">
          characters, case of
        </indexterm>
      </cindex>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="953">
          changing case of characters
        </indexterm>
      </cindex>
      <para>
        Synopsis:
      </para>
      <example endspaces=" ">
        <pre xml:space="preserve">
          \uppercase
Default handler: &lbrace;
          <var>
            text
          </var>
Default handler: &rbrace;
           \lowercase
Default handler: &lbrace;
          <var>
            text
          </var>
Default handler: &rbrace;
           \MakeUppercase
Default handler: &lbrace;
          <var>
            text
          </var>
Default handler: &rbrace;
           \MakeLowercase
Default handler: &lbrace;
          <var>
            text
          </var>
Default handler: &rbrace;
        </pre>
      </example>
      <para>
        Change the case of characters. The
Default handler: &tex;
         primitive commands
        <code>
          \uppercase
        </code>
         and
        <code>
          \lowercase
        </code>
         are set up by default to work only with the 26 letters a
Default handler: &textndash;
        z and A
Default handler: &textndash;
        Z. The
Default handler: &latex;
         commands
        <code>
          \MakeUppercase
        </code>
         and
        <code>
          \MakeLowercase
        </code>
         commands also change characters accessed by commands such as
        <code>
          \ae
        </code>
         or
        <code>
          \aa
        </code>
        . The commands
        <code>
          \MakeUppercase
        </code>
         and
        <code>
          \MakeLowercase
        </code>
         are robust but they have moving arguments (
        <pxref label="_005cprotect">
          <xrefnodename>
            \protect
          </xrefnodename>
        </pxref>
        ).
      </para>
      <para>
        These commands do not change the case of letters used in the name of a command within
        <var>
          text
        </var>
        . But they do change the case of every other Latin letter inside the argument
        <var>
          text
        </var>
        . Thus,
        <code>
          \MakeUppercase
Default handler: &lbrace;
          Let $y=f(x)$
        </code>
Default handler: &rbrace;
         produces
        <samp>
          LET Y=F(X)
        </samp>
        . Another example is that the name of an environment will be changed, so that
        <code>
          \MakeUppercase
Default handler: &lbrace;
          \begin
Default handler: &lbrace;
          tabular
Default handler: &rbrace;
           ... \end
Default handler: &lbrace;
          tabular
Default handler: &rbrace;
Default handler: &rbrace;
        </code>
         will produce an error because the first half is changed to
        <code>
          \begin
Default handler: &lbrace;
          TABULAR
Default handler: &rbrace;
        </code>
        .
      </para>
      <paraDefault handler: &latex;
>
         uses the same fixed table for changing case throughout a document, The table used is designed for the font encoding T1; this works well with the standard
Default handler: &tex;
         fonts for all Latin alphabets but will cause problems when using other alphabets.
      </para>
      <para>
        To change the case of text that results from a macro inside
        <var>
          text
        </var>
         you need to do expansion. Here the
        <code>
          \Schoolname
        </code>
         produces
        <samp>
          COLLEGE OF MATHEMATICS
        </samp>
        .
      </para>
      <example endspaces=" ">
        <pre xml:space="preserve">
          \newcommand
Default handler: &lbrace;
          \schoolname
Default handler: &rbrace;
Default handler: &lbrace;
          College of Mathematics
Default handler: &rbrace;
           \newcommand
Default handler: &lbrace;
          \Schoolname
Default handler: &rbrace;
Default handler: &lbrace;
          \expandafter\MakeUppercase
          <w/>
          \expandafter
Default handler: &lbrace;
          \schoolname
Default handler: &rbrace;
Default handler: &rbrace;
        </pre>
      </example>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="954">
          <r>
            package
          </r>
          ,
          <code>
            textcase
          </code>
        </indexterm>
      </cindex>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="955">
          <code>
            textcase
          </code>
          <r>
            package
          </r>
        </indexterm>
      </cindex>
      <para>
        The
        <code>
          textcase
        </code>
         package brings some of the missing feature of the standard
Default handler: &latex;
         commands
        <code>
          \MakeUppercase
        </code>
         and
        <code>
          \MakeLowerCase
        </code>
        .
      </para>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="956">
          <r>
            package
          </r>
          ,
          <code>
            mfirstuc
          </code>
        </indexterm>
      </cindex>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="957">
          <code>
            mfirstuc
          </code>
          <r>
            package
          </r>
        </indexterm>
      </cindex>
      <para>
        To uppercase only the first letter of words, you can use the package
        <code>
          mfirstuc
        </code>
        .
      </para>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="958">
          <r>
            package
          </r>
          ,
          <code>
            expl3
          </code>
        </indexterm>
      </cindex>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="959">
          <code>
            expl3
          </code>
          <r>
            package
          </r>
        </indexterm>
      </cindex>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="960">
          Wright, Joseph
        </indexterm>
      </cindex>
      <para>
        Handling all the casing rules specified by Unicode, e.g., for non-Latin scripts, is a much bigger job than anything envisioned in the original
Default handler: &tex;
         and
Default handler: &latex;
        . It has been implemented in the
        <code>
          expl3
        </code>
         package as of 2020. The article
Default handler: &textldquo;
        Case changing: From
Default handler: &tex;
         primitives to the Unicode algorithm
Default handler: &textrdquo;
        , (Joseph Wright,
        <cite>
          TUGboat
        </cite>
Default handler: &nbsp;
        41:1,
        <url>
          <urefurl>
            https://tug.org/TUGboat/tb41-1/tb127wright-case.pdf
          </urefurl>
        </url>
        ), gives a good overview of the topic, past and present.
      </para>
    </section>
    <node name="Symbols-by-font-position" spaces=" ">
      <nodename>
        Symbols by font position
      </nodename>
      <nodenext automatic="on">
        Text symbols
      </nodenext>
      <nodeprev automatic="on">
        Upper and lower case
      </nodeprev>
      <nodeup automatic="on">
        Special insertions
      </nodeup>
    </node>
    <section spaces=" ">
      <sectiontitle>
        Symbols by font position
      </sectiontitle>
      <findex index="fn" spaces=" ">
        <indexterm index="fn" number="1029" mergedindex="cp">
          \symbol
        </indexterm>
      </findex>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="961">
          accessing any character of a font
        </indexterm>
      </cindex>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="962">
          font symbols, by number
        </indexterm>
      </cindex>
      <para>
        You can access any character of the current font using its number with the
        <code>
          \symbol
        </code>
         command. For example, the visible space character used in the
        <code>
          \verb*
        </code>
         command has the code decimal 32 in the standard Computer Modern typewriter font, so it can be typed as
        <code>
          \symbol
Default handler: &lbrace;
          32
Default handler: &rbrace;
        </code>
        .
      </para>
      <para>
        You can also specify numbers in octal (base 8) by using a
        <code>
          '
        </code>
         prefix, or hexadecimal (base 16) with a
        <code>
          "
        </code>
         prefix, so the visible space at 32 decimal could also be written as
        <code>
          \symbol
Default handler: &lbrace;
          '40
Default handler: &rbrace;
        </code>
         or
        <code>
          \symbol
Default handler: &lbrace;
          "
          20
Default handler: &rbrace;
        </code>
        .
      </para>
    </section>
    <node name="Text-symbols" spaces=" ">
      <nodename>
        Text symbols
      </nodename>
      <nodenext automatic="on">
        Accents
      </nodenext>
      <nodeprev automatic="on">
        Symbols by font position
      </nodeprev>
      <nodeup automatic="on">
        Special insertions
      </nodeup>
    </node>
    <section spaces=" ">
      <sectiontitle>
        Text symbols
      </sectiontitle>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="963">
          text symbols
        </indexterm>
      </cindex>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="964">
          symbols, text
        </indexterm>
      </cindex>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="965">
          <r>
            package
          </r>
          ,
          <code>
            textcomp
          </code>
        </indexterm>
      </cindex>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="966">
          <code>
            textcomp
          </code>
          <r>
            package
          </r>
        </indexterm>
      </cindex>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="967">
          TS1 encoding
        </indexterm>
      </cindex>
      <paraDefault handler: &latex;
>
         provides commands to generate a number of non-letter symbols in running text. Some of these, especially the more obscure ones, are not available in OT1. As of the
Default handler: &latex;
         February 2020 release, all symbols are available by default; before that, it was necessary to use the
        <code>
          textcomp
        </code>
         package for some (technically, those in the
        <code>
          TS1
        </code>
         font encoding).
      </para>
      <ftable commandarg="code" spaces=" " endspaces=" ">
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                <indexterm index="fn" number="1030" mergedindex="cp">
                  \copyright
                </indexterm>
                \copyright
              </itemformat>
            </item>
            <itemx spaces=" ">
              <itemformat command="code">
                <indexterm index="fn" number="1031" mergedindex="cp">
                  \textcopyright
                </indexterm>
                \textcopyright
              </itemformat>
            </itemx>
          </tableterm>
          <tableitem>
            <cindex index="cp" spaces=" ">
              <indexterm index="cp" number="968">
                copyright symbol
              </indexterm>
            </cindex>
            <paraDefault handler: &copyright;
>
               The copyright symbol.
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                <indexterm index="fn" number="1032" mergedindex="cp">
                  \dag
                </indexterm>
                \dag
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <cindex index="cp" spaces=" ">
              <indexterm index="cp" number="969">
                dagger, in text
              </indexterm>
            </cindex>
            <para>
              <u>
                2020
              </u>
               The dagger symbol (in text).
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                <indexterm index="fn" number="1033" mergedindex="cp">
                  \ddag
                </indexterm>
                \ddag
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <cindex index="cp" spaces=" ">
              <indexterm index="cp" number="970">
                double dagger, in text
              </indexterm>
            </cindex>
            <para>
              <u>
                2021
              </u>
               The double dagger symbol (in text).
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                <indexterm index="fn" number="1034" mergedindex="cp">
                  \LaTeX
                </indexterm>
                \LaTeX
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <cindex index="cp" spaces=" ">
              <indexterm index="cp" number="971"Default handler: &latex;
>
                 logo
              </indexterm>
            </cindex>
            <cindex index="cp" spaces=" ">
              <indexterm index="cp" number="972">
                logo,
Default handler: &latex;
              </indexterm>
            </cindex>
            <para>
              The
Default handler: &latex;
               logo.
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                <indexterm index="fn" number="1035" mergedindex="cp">
                  \LaTeXe
                </indexterm>
                \LaTeXe
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <cindex index="cp" spaces=" ">
              <indexterm index="cp" number="973"Default handler: &latex;
>
                2e logo
              </indexterm>
            </cindex>
            <cindex index="cp" spaces=" ">
              <indexterm index="cp" number="974">
                logo,
Default handler: &latex;
                2e
              </indexterm>
            </cindex>
            <para>
              The
Default handler: &latex;
              2e logo.
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                <indexterm index="fn" number="1036" mergedindex="cp">
                  \guillemetleft
                  <r>
                    (
Default handler: &laquo;
                    )
                  </r>
                </indexterm>
                \guillemetleft
                <r>
                  (
Default handler: &laquo;
                  )
                </r>
              </itemformat>
            </item>
            <itemx spaces=" ">
              <itemformat command="code">
                <indexterm index="fn" number="1037" mergedindex="cp">
                  \guillemetright
                  <r>
                    (
Default handler: &raquo;
                    )
                  </r>
                </indexterm>
                \guillemetright
                <r>
                  (
Default handler: &raquo;
                  )
                </r>
              </itemformat>
            </itemx>
            <itemx spaces=" ">
              <itemformat command="code">
                <indexterm index="fn" number="1038" mergedindex="cp">
                  \guillemotleft
                  <r>
                    (
Default handler: &guillemotleft;
                    )
                  </r>
                </indexterm>
                \guillemotleft
                <r>
                  (
Default handler: &guillemotleft;
                  )
                </r>
              </itemformat>
            </itemx>
            <itemx spaces=" ">
              <itemformat command="code">
                <indexterm index="fn" number="1039" mergedindex="cp">
                  \guillemotright
                  <r>
                    (
Default handler: &guillemotright;
                    )
                  </r>
                </indexterm>
                \guillemotright
                <r>
                  (
Default handler: &guillemotright;
                  )
                </r>
              </itemformat>
            </itemx>
            <itemx spaces=" ">
              <itemformat command="code">
                <indexterm index="fn" number="1040" mergedindex="cp">
                  \guilsinglleft
                  <r>
                    (
Default handler: &lsaquo;
                    )
                  </r>
                </indexterm>
                \guilsinglleft
                <r>
                  (
Default handler: &lsaquo;
                  )
                </r>
              </itemformat>
            </itemx>
            <itemx spaces=" ">
              <itemformat command="code">
                <indexterm index="fn" number="1041" mergedindex="cp">
                  \guilsinglright
                  <r>
                    (
Default handler: &rsaquo;
                    )
                  </r>
                </indexterm>
                \guilsinglright
                <r>
                  (
Default handler: &rsaquo;
                  )
                </r>
              </itemformat>
            </itemx>
          </tableterm>
          <tableitem>
            <cindex index="cp" spaces=" ">
              <indexterm index="cp" number="975">
                double guillemets
              </indexterm>
            </cindex>
            <cindex index="cp" spaces=" ">
              <indexterm index="cp" number="976">
                single guillemets
              </indexterm>
            </cindex>
            <cindex index="cp" spaces=" ">
              <indexterm index="cp" number="977">
                left angle quotation marks
              </indexterm>
            </cindex>
            <cindex index="cp" spaces=" ">
              <indexterm index="cp" number="978">
                right angle quotation marks
              </indexterm>
            </cindex>
            <cindex index="cp" spaces=" ">
              <indexterm index="cp" number="979">
                double angle quotation marks
              </indexterm>
            </cindex>
            <cindex index="cp" spaces=" ">
              <indexterm index="cp" number="980">
                single angle quotation marks
              </indexterm>
            </cindex>
            <cindex index="cp" spaces=" ">
              <indexterm index="cp" number="981">
                French quotation marks
              </indexterm>
            </cindex>
            <cindex index="cp" spaces=" ">
              <indexterm index="cp" number="982">
                quotation marks, French
              </indexterm>
            </cindex>
            <cindex index="cp" spaces=" ">
              <indexterm index="cp" number="983">
                guillemots, birds
              </indexterm>
            </cindex>
            <paraDefault handler: &laquo;
>
              ,
Default handler: &raquo;
              ,
Default handler: &lsaquo;
              ,
Default handler: &rsaquo;
               Double and single angle quotation marks, commonly used in French. The commands
              <codeDefault handler: &arobase;
>
                guillemotleft
              </code>
               and
              <codeDefault handler: &arobase;
>
                guillemotright
              </code>
               are synonyms for
              <codeDefault handler: &arobase;
>
                guillemet...
              </code>
              ; these are misspellings inherited from Adobe. (Guillemots are seabirds; guillemets are French quotes.)
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                <indexterm index="fn" number="1042" mergedindex="cp">
                  \ldots
                </indexterm>
                \ldots
              </itemformat>
            </item>
            <itemx spaces=" ">
              <itemformat command="code">
                <indexterm index="fn" number="1043" mergedindex="cp">
                  \textellipsis
                </indexterm>
                \textellipsis
              </itemformat>
            </itemx>
            <itemx spaces=" ">
              <itemformat command="code">
                <indexterm index="fn" number="1044" mergedindex="cp">
                  \dots
                </indexterm>
                \dots
              </itemformat>
            </itemx>
          </tableterm>
          <tableitem>
            <cindex index="cp" spaces=" ">
              <indexterm index="cp" number="984">
                ellipsis
              </indexterm>
            </cindex>
            <paraDefault handler: &dots;
>
               An ellipsis (three dots at the baseline):
              <code>
                \ldots
              </code>
               and
              <code>
                \dots
              </code>
               also work in math mode (
              <pxref label="Dots">
                <xrefnodename>
                  Dots
                </xrefnodename>
              </pxref>
              ). See that math mode ellipsis description for additional general information.
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                <indexterm index="fn" number="1045" mergedindex="cp">
                  \lq
                </indexterm>
                \lq
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <cindex index="cp" spaces=" ">
              <indexterm index="cp" number="985">
                left quote
              </indexterm>
            </cindex>
            <cindex index="cp" spaces=" ">
              <indexterm index="cp" number="986">
                opening quote
              </indexterm>
            </cindex>
            <paraDefault handler: &textlsquo;
>
               Left (opening) quote.
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                <indexterm index="fn" number="1046" mergedindex="cp">
                  \P
                </indexterm>
                \P
              </itemformat>
            </item>
            <itemx spaces=" ">
              <itemformat command="code">
                <indexterm index="fn" number="1047" mergedindex="cp">
                  \textparagraph
                </indexterm>
                \textparagraph
              </itemformat>
            </itemx>
          </tableterm>
          <tableitem>
            <cindex index="cp" spaces=" ">
              <indexterm index="cp" number="987">
                paragraph symbol
              </indexterm>
            </cindex>
            <cindex index="cp" spaces=" ">
              <indexterm index="cp" number="988">
                pilcrow
              </indexterm>
            </cindex>
            <para>
              <u>
                00B6
              </u>
               Paragraph sign (pilcrow).
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                <indexterm index="fn" number="1048" mergedindex="cp">
                  \pounds
                </indexterm>
                \pounds
              </itemformat>
            </item>
            <itemx spaces=" ">
              <itemformat command="code">
                <indexterm index="fn" number="1049" mergedindex="cp">
                  \textsterling
                </indexterm>
                \textsterling
              </itemformat>
            </itemx>
          </tableterm>
          <tableitem>
            <cindex index="cp" spaces=" ">
              <indexterm index="cp" number="989">
                pounds symbol
              </indexterm>
            </cindex>
            <cindex index="cp" spaces=" ">
              <indexterm index="cp" number="990">
                sterling symbol
              </indexterm>
            </cindex>
            <paraDefault handler: &pound;
>
               English pounds sterling.
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                <indexterm index="fn" number="1050" mergedindex="cp">
                  \quotedblbase
                  <r>
                    (
Default handler: &bdquo;
                    )
                  </r>
                </indexterm>
                \quotedblbase
                <r>
                  (
Default handler: &bdquo;
                  )
                </r>
              </itemformat>
            </item>
            <itemx spaces=" ">
              <itemformat command="code">
                <indexterm index="fn" number="1051" mergedindex="cp">
                  \quotesinglbase
                  <r>
                    (
Default handler: &sbquo;
                    )
                  </r>
                </indexterm>
                \quotesinglbase
                <r>
                  (
Default handler: &sbquo;
                  )
                </r>
              </itemformat>
            </itemx>
          </tableterm>
          <tableitem>
            <cindex index="cp" spaces=" ">
              <indexterm index="cp" number="991">
                double low-9 quotation mark
              </indexterm>
            </cindex>
            <cindex index="cp" spaces=" ">
              <indexterm index="cp" number="992">
                single low-9 quotation mark
              </indexterm>
            </cindex>
            <cindex index="cp" spaces=" ">
              <indexterm index="cp" number="993">
                low-9 quotation marks, single and double
              </indexterm>
            </cindex>
            <paraDefault handler: &bdquo;
>
               and
Default handler: &sbquo;
               Double and single quotation marks on the baseline.
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                <indexterm index="fn" number="1052" mergedindex="cp">
                  \rq
                </indexterm>
                \rq
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <cindex index="cp" spaces=" ">
              <indexterm index="cp" number="994">
                right quote
              </indexterm>
            </cindex>
            <cindex index="cp" spaces=" ">
              <indexterm index="cp" number="995">
                closing quote
              </indexterm>
            </cindex>
            <paraDefault handler: &textrsquo;
>
               Right (closing) quote.
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                <indexterm index="fn" number="1053" mergedindex="cp">
                  \S
                </indexterm>
                \S
              </itemformat>
            </item>
            <itemx spaces=" ">
              <itemformat command="code">
                <indexterm index="fn" number="1054" mergedindex="cp">
                  \textsection
                </indexterm>
                \textsection
              </itemformat>
            </itemx>
          </tableterm>
          <tableitem>
            <cindex index="cp" spaces=" ">
              <indexterm index="cp" number="996">
                section symbol
              </indexterm>
            </cindex>
            <para>
              <u>
                00A7
              </u>
               Section sign.
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                <indexterm index="fn" number="1055" mergedindex="cp">
                  \TeX
                </indexterm>
                \TeX
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <cindex index="cp" spaces=" ">
              <indexterm index="cp" number="997"Default handler: &tex;
>
                 logo
              </indexterm>
            </cindex>
            <cindex index="cp" spaces=" ">
              <indexterm index="cp" number="998">
                logo,
Default handler: &tex;
              </indexterm>
            </cindex>
            <para>
              The
Default handler: &tex;
               logo.
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                <indexterm index="fn" number="1056" mergedindex="cp">
                  \textasciicircum
                </indexterm>
                \textasciicircum
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <cindex index="cp" spaces=" ">
              <indexterm index="cp" number="999">
                circumflex, ASCII, in text
              </indexterm>
            </cindex>
            <cindex index="cp" spaces=" ">
              <indexterm index="cp" number="1000">
                ASCII circumflex, in text
              </indexterm>
            </cindex>
            <para>
              ^ ASCII circumflex.
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                <indexterm index="fn" number="1057" mergedindex="cp">
                  \textasciitilde
                </indexterm>
                \textasciitilde
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <cindex index="cp" spaces=" ">
              <indexterm index="cp" number="1001">
                tilde, ASCII, in text
              </indexterm>
            </cindex>
            <cindex index="cp" spaces=" ">
              <indexterm index="cp" number="1002">
                ASCII tilde, in text
              </indexterm>
            </cindex>
            <para>
              ~ ASCII tilde.
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                <indexterm index="fn" number="1058" mergedindex="cp">
                  \textasteriskcentered
                </indexterm>
                \textasteriskcentered
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <cindex index="cp" spaces=" ">
              <indexterm index="cp" number="1003">
                asterisk, centered, in text
              </indexterm>
            </cindex>
            <cindex index="cp" spaces=" ">
              <indexterm index="cp" number="1004">
                centered asterisk, in text
              </indexterm>
            </cindex>
            <para>
              * Centered asterisk.
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                <indexterm index="fn" number="1059" mergedindex="cp">
                  \textbackslash
                </indexterm>
                \textbackslash
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <cindex index="cp" spaces=" ">
              <indexterm index="cp" number="1005">
                backslash, in text
              </indexterm>
            </cindex>
            <para>
              \ Backslash. However,
              <code>
                \texttt
Default handler: &lbrace;
                \textbackslash
Default handler: &rbrace;
              </code>
               produces a roman (not typewriter) backslash by default; for a typewriter backslash, it is necessary to use the T1 (or other non-default) font encoding, as in:
            </para>
            <example endspaces=" ">
              <pre xml:space="preserve">
                \usepackage[T1]
Default handler: &lbrace;
                fontenc
Default handler: &rbrace;
              </pre>
            </example>
Default handler: <!-- c https://github.com/latex3/latex2e/issues/824 -->
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                <indexterm index="fn" number="1060" mergedindex="cp">
                  \textbar
                </indexterm>
                \textbar
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <cindex index="cp" spaces=" ">
              <indexterm index="cp" number="1006">
                vertical bar, in text
              </indexterm>
            </cindex>
            <cindex index="cp" spaces=" ">
              <indexterm index="cp" number="1007">
                bar, vertical, in text
              </indexterm>
            </cindex>
            <para>
              | Vertical bar.
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                <indexterm index="fn" number="1061" mergedindex="cp">
                  \textbardbl
                </indexterm>
                \textbardbl
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <cindex index="cp" spaces=" ">
              <indexterm index="cp" number="1008">
                vertical bar, double, in text
              </indexterm>
            </cindex>
            <cindex index="cp" spaces=" ">
              <indexterm index="cp" number="1009">
                bar, double vertical, in text
              </indexterm>
            </cindex>
            <cindex index="cp" spaces=" ">
              <indexterm index="cp" number="1010">
                double vertical bar, in text
              </indexterm>
            </cindex>
            <para>
              <u>
                23F8
              </u>
               Double vertical bar.
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                <indexterm index="fn" number="1062" mergedindex="cp">
                  \textbigcircle
                </indexterm>
                \textbigcircle
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <cindex index="cp" spaces=" ">
              <indexterm index="cp" number="1011">
                big circle symbols, in text
              </indexterm>
            </cindex>
            <cindex index="cp" spaces=" ">
              <indexterm index="cp" number="1012">
                circle symbol, big, in text
              </indexterm>
            </cindex>
            <para>
              <u>
                25EF
              </u>
              , Big circle symbol.
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                <indexterm index="fn" number="1063" mergedindex="cp">
                  \textbraceleft
                </indexterm>
                \textbraceleft
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <cindex index="cp" spaces=" ">
              <indexterm index="cp" number="1013">
                left brace, in text
              </indexterm>
            </cindex>
            <cindex index="cp" spaces=" ">
              <indexterm index="cp" number="1014">
                brace, left, in text
              </indexterm>
            </cindex>
            <paraDefault handler: &lbrace;
>
               Left brace. See remarks at
              <code>
                \textbackslash
              </code>
               above about making
              <code>
                \texttt
Default handler: &lbrace;
                \textbraceleft
Default handler: &rbrace;
              </code>
               produce a typewriter brace.
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                <indexterm index="fn" number="1064" mergedindex="cp">
                  \textbraceright
                </indexterm>
                \textbraceright
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <cindex index="cp" spaces=" ">
              <indexterm index="cp" number="1015">
                right brace, in text
              </indexterm>
            </cindex>
            <cindex index="cp" spaces=" ">
              <indexterm index="cp" number="1016">
                brace, right, in text
              </indexterm>
            </cindex>
            <paraDefault handler: &rbrace;
>
               Right brace. See remarks at
              <code>
                \textbackslash
              </code>
               above about making
              <code>
                \texttt
Default handler: &lbrace;
                \textbraceright
Default handler: &rbrace;
              </code>
               produce a typewriter brace.
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                <indexterm index="fn" number="1065" mergedindex="cp">
                  \textbullet
                </indexterm>
                \textbullet
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <cindex index="cp" spaces=" ">
              <indexterm index="cp" number="1017">
                bullet, in text
              </indexterm>
            </cindex>
            <paraDefault handler: &bullet;
>
               Bullet.
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                <indexterm index="fn" number="1066" mergedindex="cp">
                  \textcircled
Default handler: &lbrace;
                  <var>
                    letter
                  </var>
Default handler: &rbrace;
                </indexterm>
                \textcircled
Default handler: &lbrace;
                <var>
                  letter
                </var>
Default handler: &rbrace;
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <cindex index="cp" spaces=" ">
              <indexterm index="cp" number="1018">
                circled letter, in text
              </indexterm>
            </cindex>
            <para>
              <u>
                24B6
              </u>
              , Circle around
              <var>
                letter
              </var>
              .
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                <indexterm index="fn" number="1067" mergedindex="cp">
                  \textcompwordmark
                </indexterm>
                \textcompwordmark
              </itemformat>
            </item>
            <itemx spaces=" ">
              <itemformat command="code">
                <indexterm index="fn" number="1068" mergedindex="cp">
                  \textcapitalcompwordmark
                </indexterm>
                \textcapitalcompwordmark
              </itemformat>
            </itemx>
            <itemx spaces=" ">
              <itemformat command="code">
                <indexterm index="fn" number="1069" mergedindex="cp">
                  \textascendercompwordmark
                </indexterm>
                \textascendercompwordmark
              </itemformat>
            </itemx>
          </tableterm>
          <tableitem>
            <cindex index="cp" spaces=" ">
              <indexterm index="cp" number="1019">
                composite word mark, in text
              </indexterm>
            </cindex>
            <cindex index="cp" spaces=" ">
              <indexterm index="cp" number="1020">
                cap height
              </indexterm>
            </cindex>
            <cindex index="cp" spaces=" ">
              <indexterm index="cp" number="1021">
                ascender height
              </indexterm>
            </cindex>
            <para>
              Used to separate letters that would normally ligature. For example,
              <code>
                f\textcompwordmark i
              </code>
               produces
              <samp>
                fi
              </samp>
               without a ligature. This is most useful in non-English languages. The
              <code>
                \textcapitalcompwordmark
              </code>
               form has the cap height of the font while the
              <code>
                \textascendercompwordmark
              </code>
               form has the ascender height.
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                <indexterm index="fn" number="1070" mergedindex="cp">
                  \textdagger
                </indexterm>
                \textdagger
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <cindex index="cp" spaces=" ">
              <indexterm index="cp" number="1022">
                dagger, in text
              </indexterm>
            </cindex>
            <para>
              <u>
                2020
              </u>
               Dagger.
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                <indexterm index="fn" number="1071" mergedindex="cp">
                  \textdaggerdbl
                </indexterm>
                \textdaggerdbl
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <cindex index="cp" spaces=" ">
              <indexterm index="cp" number="1023">
                dagger, double, in text
              </indexterm>
            </cindex>
            <cindex index="cp" spaces=" ">
              <indexterm index="cp" number="1024">
                double dagger, in text
              </indexterm>
            </cindex>
            <para>
              <u>
                2021
              </u>
               Double dagger.
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                <indexterm index="fn" number="1072" mergedindex="cp">
                  \textdollar
                  <r>
                    (or
                    <code>
                      \$
                    </code>
                    )
                  </r>
                </indexterm>
                \textdollar
                <r>
                  (or
                  <code>
                    \$
                  </code>
                  )
                </r>
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <cindex index="cp" spaces=" ">
              <indexterm index="cp" number="1025">
                dollar sign
              </indexterm>
            </cindex>
            <cindex index="cp" spaces=" ">
              <indexterm index="cp" number="1026">
                currency, dollar
              </indexterm>
            </cindex>
            <para>
              $ Dollar sign.
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                <indexterm index="fn" number="1073" mergedindex="cp">
                  \textemdash
                  <r>
                    (or
                    <code>
                      ---
                    </code>
                    )
                  </r>
                </indexterm>
                \textemdash
                <r>
                  (or
                  <code>
                    ---
                  </code>
                  )
                </r>
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <cindex index="cp" spaces=" ">
              <indexterm index="cp" number="1027">
                em-dash
              </indexterm>
            </cindex>
            <raggedright endspaces=" ">
              <paraDefault handler: &textmdash;
>
                 Em-dash. Used for punctuation, usually similar to commas or parentheses, as in
Default handler: &textlsquo;
                <code>
                  The playoffs---if you're lucky enough to make the playoffs---are more like a sprint.
                </code>
Default handler: &textrsquo;
                 Conventions for spacing around em-dashes vary widely.
              </para>
            </raggedright>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                <indexterm index="fn" number="1074" mergedindex="cp">
                  \textendash
                  <r>
                    (or
                    <code>
                      --
                    </code>
                    )
                  </r>
                </indexterm>
                \textendash
                <r>
                  (or
                  <code>
                    --
                  </code>
                  )
                </r>
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <cindex index="cp" spaces=" ">
              <indexterm index="cp" number="1028">
                e-dash
              </indexterm>
            </cindex>
            <paraDefault handler: &textndash;
>
               En-dash. Used for ranges, as in
Default handler: &textlsquo;
              <code>
                see pages 12--14
              </code>
Default handler: &textrsquo;
              .
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                <indexterm index="fn" number="1075" mergedindex="cp">
                  \texteuro
                </indexterm>
                \texteuro
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <cindex index="cp" spaces=" ">
              <indexterm index="cp" number="1029">
                euro symbol
              </indexterm>
            </cindex>
            <cindex index="cp" spaces=" ">
              <indexterm index="cp" number="1030">
                currency, euro
              </indexterm>
            </cindex>
            <cindex index="cp" spaces=" ">
              <indexterm index="cp" number="1031">
                <r>
                  package
                </r>
                ,
                <code>
                  eurosym
                </code>
              </indexterm>
            </cindex>
            <cindex index="cp" spaces=" ">
              <indexterm index="cp" number="1032">
                <code>
                  eurosym
                </code>
                <r>
                  package
                </r>
              </indexterm>
            </cindex>
            <para>
              The Euro currency symbol:
Default handler: &euro;
              .
              <cindex index="cp" spaces=" ">
                <indexterm index="cp" number="1033">
                  <r>
                    package
                  </r>
                  ,
                  <code>
                    eurosym
                  </code>
                </indexterm>
              </cindex>
              <cindex index="cp" spaces=" ">
                <indexterm index="cp" number="1034">
                  <code>
                    eurosym
                  </code>
                  <r>
                    package
                  </r>
                </indexterm>
              </cindex>
            </para>
            <para>
              For an alternative glyph design, try the
              <code>
                eurosym
              </code>
               package; also, most fonts nowadays come with their own Euro symbol (Unicode U+20AC).
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                <indexterm index="fn" number="1076" mergedindex="cp">
                  \textexclamdown
                  <r>
                    (or
                    <code>
                      !`
                    </code>
                    )
                  </r>
                </indexterm>
                \textexclamdown
                <r>
                  (or
                  <code>
                    !`
                  </code>
                  )
                </r>
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <cindex index="cp" spaces=" ">
              <indexterm index="cp" number="1035">
                exclamation point, upside-down
              </indexterm>
            </cindex>
            <paraDefault handler: &iexcl;
>
               Upside down exclamation point.
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                <indexterm index="fn" number="1077" mergedindex="cp">
                  \textfiguredash
                </indexterm>
                \textfiguredash
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <cindex index="cp" spaces=" ">
              <indexterm index="cp" number="1036">
                figure dash character
              </indexterm>
            </cindex>
            <para>
              Dash used between numerals, Unicode U+2012. Defined in the June 2021 release of
Default handler: &latex;
              . When used in pdf
Default handler: &tex;
              , approximated by an en-dash; with a Unicode engine, either typesets the glyph if available in the current font, or writes the usual
Default handler: &textldquo;
              Missing character
Default handler: &textrdquo;
               warning to the log file.
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                <indexterm index="fn" number="1078" mergedindex="cp">
                  \textgreater
                </indexterm>
                \textgreater
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <cindex index="cp" spaces=" ">
              <indexterm index="cp" number="1037">
                greater than symbol, in text
              </indexterm>
            </cindex>
            <para>
              >
               Greater than symbol.
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                <indexterm index="fn" number="1079" mergedindex="cp">
                  \texthorizontalbar
                </indexterm>
                \texthorizontalbar
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <cindex index="cp" spaces=" ">
              <indexterm index="cp" number="1038">
                horizontal bar character
              </indexterm>
            </cindex>
            <para>
              Horizontal bar character, Unicode U+2015. Defined in the June 2021 release of
Default handler: &latex;
              . Behavior as with
              <code>
                \textfiguredash
              </code>
               above; the pdf
Default handler: &tex;
               approximation is an em-dash.
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                <indexterm index="fn" number="1080" mergedindex="cp">
                  \textless
                </indexterm>
                \textless
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <cindex index="cp" spaces=" ">
              <indexterm index="cp" number="1039">
                less than symbol, in text
              </indexterm>
            </cindex>
            <para>
              <
               Less than symbol.
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                <indexterm index="fn" number="1081" mergedindex="cp">
                  \textleftarrow
                </indexterm>
                \textleftarrow
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <cindex index="cp" spaces=" ">
              <indexterm index="cp" number="1040">
                arrow, left, in text
              </indexterm>
            </cindex>
            <cindex index="cp" spaces=" ">
              <indexterm index="cp" number="1041">
                left arrow, in text
              </indexterm>
            </cindex>
            <para>
              <u>
                2190
              </u>
              , Left arrow.
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                <indexterm index="fn" number="1082" mergedindex="cp">
                  \textnonbreakinghyphen
                </indexterm>
                \textnonbreakinghyphen
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <cindex index="cp" spaces=" ">
              <indexterm index="cp" number="1042">
                non-breaking hyphen character
              </indexterm>
            </cindex>
            <cindex index="cp" spaces=" ">
              <indexterm index="cp" number="1043">
                hyphen character, non-breaking
              </indexterm>
            </cindex>
            <para>
              Non-breaking hyphen character, Unicode U+2011. Defined in the June 2021 release of
Default handler: &latex;
              . Behavior as with
              <code>
                \textfiguredash
              </code>
               above; the pdf
Default handler: &tex;
               approximation is a regular ASCII hyphen (with breaks disallowed after).
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                <indexterm index="fn" number="1083" mergedindex="cp">
                  \textordfeminine
                </indexterm>
                \textordfeminine
              </itemformat>
            </item>
            <itemx spaces=" ">
              <itemformat command="code">
                <indexterm index="fn" number="1084" mergedindex="cp">
                  \textordmasculine
                </indexterm>
                \textordmasculine
              </itemformat>
            </itemx>
          </tableterm>
          <tableitem>
            <cindex index="cp" spaces=" ">
              <indexterm index="cp" number="1044">
                feminine ordinal symbol
              </indexterm>
            </cindex>
            <cindex index="cp" spaces=" ">
              <indexterm index="cp" number="1045">
                masculine ordinal symbol
              </indexterm>
            </cindex>
            <cindex index="cp" spaces=" ">
              <indexterm index="cp" number="1046">
                ordinals, feminine and masculine
              </indexterm>
            </cindex>
            <cindex index="cp" spaces=" ">
              <indexterm index="cp" number="1047">
                Spanish ordinals, feminine and masculine
              </indexterm>
            </cindex>
            <paraDefault handler: &ordf;
>
              ,
Default handler: &ordm;
               Feminine and masculine ordinal symbols.
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                <indexterm index="fn" number="1085" mergedindex="cp">
                  \textperiodcentered
                </indexterm>
                \textperiodcentered
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <cindex index="cp" spaces=" ">
              <indexterm index="cp" number="1048">
                period, centered, in text
              </indexterm>
            </cindex>
            <cindex index="cp" spaces=" ">
              <indexterm index="cp" number="1049">
                centered period, in text
              </indexterm>
            </cindex>
            <para>
              <u>
                00B7
              </u>
               Centered period.
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                <indexterm index="fn" number="1086" mergedindex="cp">
                  \textquestiondown
                  <r>
                    (or
                    <code>
                      ?`
                    </code>
                    )
                  </r>
                </indexterm>
                \textquestiondown
                <r>
                  (or
                  <code>
                    ?`
                  </code>
                  )
                </r>
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <cindex index="cp" spaces=" ">
              <indexterm index="cp" number="1050">
                question mark, upside-down
              </indexterm>
            </cindex>
            <paraDefault handler: &iquest;
>
               Upside down question mark.
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                <indexterm index="fn" number="1087" mergedindex="cp">
                  \textquotedblleft
                  <r>
                    (or
                    <code>
                      ``
                    </code>
                    )
                  </r>
                </indexterm>
                \textquotedblleft
                <r>
                  (or
                  <code>
                    ``
                  </code>
                  )
                </r>
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <cindex index="cp" spaces=" ">
              <indexterm index="cp" number="1051">
                left quote, double
              </indexterm>
            </cindex>
            <cindex index="cp" spaces=" ">
              <indexterm index="cp" number="1052">
                double left quote
              </indexterm>
            </cindex>
            <paraDefault handler: &textldquo;
>
               Double left quote.
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                <indexterm index="fn" number="1088" mergedindex="cp">
                  \textquotedblright
                  <r>
                    (or
                    <code>
                      ''
                    </code>
                    )
                  </r>
                </indexterm>
                \textquotedblright
                <r>
                  (or
                  <code>
                    ''
                  </code>
                  )
                </r>
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <cindex index="cp" spaces=" ">
              <indexterm index="cp" number="1053">
                right quote, double
              </indexterm>
            </cindex>
            <cindex index="cp" spaces=" ">
              <indexterm index="cp" number="1054">
                double right quote
              </indexterm>
            </cindex>
            <paraDefault handler: &textrdquo;
>
               Double right quote.
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                <indexterm index="fn" number="1089" mergedindex="cp">
                  \textquoteleft
                  <r>
                    (or
                    <code>
                      `
                    </code>
                    )
                  </r>
                </indexterm>
                \textquoteleft
                <r>
                  (or
                  <code>
                    `
                  </code>
                  )
                </r>
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <cindex index="cp" spaces=" ">
              <indexterm index="cp" number="1055">
                left quote, single
              </indexterm>
            </cindex>
            <cindex index="cp" spaces=" ">
              <indexterm index="cp" number="1056">
                single left quote
              </indexterm>
            </cindex>
            <paraDefault handler: &textlsquo;
>
               Single left quote.
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                <indexterm index="fn" number="1090" mergedindex="cp">
                  \textquoteright
                  <r>
                    (or
                    <code>
                      '
                    </code>
                    )
                  </r>
                </indexterm>
                \textquoteright
                <r>
                  (or
                  <code>
                    '
                  </code>
                  )
                </r>
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <cindex index="cp" spaces=" ">
              <indexterm index="cp" number="1057">
                right quote, single
              </indexterm>
            </cindex>
            <cindex index="cp" spaces=" ">
              <indexterm index="cp" number="1058">
                single right quote
              </indexterm>
            </cindex>
            <paraDefault handler: &textrsquo;
>
               Single right quote.
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                <indexterm index="fn" number="1091" mergedindex="cp">
                  \textquotesingle
                </indexterm>
                \textquotesingle
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <cindex index="cp" spaces=" ">
              <indexterm index="cp" number="1059">
                quote, single straight
              </indexterm>
            </cindex>
            <cindex index="cp" spaces=" ">
              <indexterm index="cp" number="1060">
                straight single quote
              </indexterm>
            </cindex>
            <cindex index="cp" spaces=" ">
              <indexterm index="cp" number="1061">
                single quote, straight
              </indexterm>
            </cindex>
            <para>
              <u>
                0027
              </u>
              , Straight single quote. (From TS1 encoding.)
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                <indexterm index="fn" number="1092" mergedindex="cp">
                  \textquotestraightbase
                </indexterm>
                \textquotestraightbase
              </itemformat>
            </item>
            <itemx spaces=" ">
              <itemformat command="code">
                <indexterm index="fn" number="1093" mergedindex="cp">
                  \textquotestraightdblbase
                </indexterm>
                \textquotestraightdblbase
              </itemformat>
            </itemx>
          </tableterm>
          <tableitem>
            <cindex index="cp" spaces=" ">
              <indexterm index="cp" number="1062">
                quote, straight base
              </indexterm>
            </cindex>
            <cindex index="cp" spaces=" ">
              <indexterm index="cp" number="1063">
                straight quote, base
              </indexterm>
            </cindex>
            <cindex index="cp" spaces=" ">
              <indexterm index="cp" number="1064">
                double quote, straight base
              </indexterm>
            </cindex>
            <cindex index="cp" spaces=" ">
              <indexterm index="cp" number="1065">
                straight double quote, base
              </indexterm>
            </cindex>
Default handler: <!-- c Unicode doesn't have these https://en.wikipedia.org/wiki/Quotation_mark -->
            <para>
              Single and double straight quotes on the baseline.
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                <indexterm index="fn" number="1094" mergedindex="cp">
                  \textregistered
                </indexterm>
                \textregistered
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <cindex index="cp" spaces=" ">
              <indexterm index="cp" number="1066">
                registered symbol
              </indexterm>
            </cindex>
            <paraDefault handler: &registered;
>
               Registered symbol.
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                <indexterm index="fn" number="1095" mergedindex="cp">
                  \textrightarrow
                </indexterm>
                \textrightarrow
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <cindex index="cp" spaces=" ">
              <indexterm index="cp" number="1067">
                arrow, right, in text
              </indexterm>
            </cindex>
            <cindex index="cp" spaces=" ">
              <indexterm index="cp" number="1068">
                right arrow, in text
              </indexterm>
            </cindex>
            <para>
              <u>
                2192
              </u>
              , Right arrow.
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                <indexterm index="fn" number="1096" mergedindex="cp">
                  \textthreequartersemdash
                </indexterm>
                \textthreequartersemdash
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <cindex index="cp" spaces=" ">
              <indexterm index="cp" number="1069">
                three-quarters em-dash
              </indexterm>
            </cindex>
            <cindex index="cp" spaces=" ">
              <indexterm index="cp" number="1070">
                em-dash, three-quarters
              </indexterm>
            </cindex>
            <para>
              <u>
                FE58
              </u>
              ,
Default handler: &textldquo;
              Three-quarters
Default handler: &textrdquo;
               em-dash, between en-dash and em-dash.
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                <indexterm index="fn" number="1097" mergedindex="cp">
                  \texttrademark
                </indexterm>
                \texttrademark
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <cindex index="cp" spaces=" ">
              <indexterm index="cp" number="1071">
                trademark symbol
              </indexterm>
            </cindex>
            <para>
              <u>
                2122
              </u>
               Trademark symbol.
            </para>
Default handler: <!-- c ?? Diff from \textthreequartersemdash? In Unicode? -->
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                <indexterm index="fn" number="1098" mergedindex="cp">
                  \texttwelveudash
                </indexterm>
                \texttwelveudash
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <cindex index="cp" spaces=" ">
              <indexterm index="cp" number="1072">
                two-thirds em-dash
              </indexterm>
            </cindex>
            <cindex index="cp" spaces=" ">
              <indexterm index="cp" number="1073">
                em-dash, two-thirds
              </indexterm>
            </cindex>
            <para>
              <u>
                FE58
              </u>
              ,
Default handler: &textldquo;
              Two-thirds
Default handler: &textrdquo;
               em-dash, between en-dash and em-dash.
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                <indexterm index="fn" number="1099" mergedindex="cp">
                  \textunderscore
                </indexterm>
                \textunderscore
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <cindex index="cp" spaces=" ">
              <indexterm index="cp" number="1074">
                underscore, in text
              </indexterm>
            </cindex>
            <para>
              _ Underscore.
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                <indexterm index="fn" number="1100" mergedindex="cp">
                  \textvisiblespace
                </indexterm>
                \textvisiblespace
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <cindex index="cp" spaces=" ">
              <indexterm index="cp" number="1075">
                visible space symbol, in text
              </indexterm>
            </cindex>
            <para>
              <u>
                2423
              </u>
              , Visible space symbol.
            </para>
          </tableitem>
        </tableentry>
      </ftable>
    </section>
    <node name="Accents" spaces=" ">
      <nodename>
        Accents
      </nodename>
      <nodenext automatic="on">
        Additional Latin letters
      </nodenext>
      <nodeprev automatic="on">
        Text symbols
      </nodeprev>
      <nodeup automatic="on">
        Special insertions
      </nodeup>
    </node>
    <section spaces=" ">
      <sectiontitle>
        Accents
      </sectiontitle>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="1076">
          accents
        </indexterm>
      </cindex>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="1077">
          characters, accented
        </indexterm>
      </cindex>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="1078">
          letters, accented
        </indexterm>
      </cindex>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="1079">
          <r>
            package
          </r>
          ,
          <code>
            babel
          </code>
        </indexterm>
      </cindex>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="1080">
          <code>
            babel
          </code>
          <r>
            package
          </r>
        </indexterm>
      </cindex>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="1081">
          <r>
            package
          </r>
          ,
          <code>
            polyglossia
          </code>
        </indexterm>
      </cindex>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="1082">
          <code>
            polyglossia
          </code>
          <r>
            package
          </r>
        </indexterm>
      </cindex>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="1083">
          multilingual support
        </indexterm>
      </cindex>
      <paraDefault handler: &latex;
>
         has wide support for many of the world
Default handler: &textrsquo;
        s scripts and languages, provided through the core
        <code>
          babel
        </code>
         package, which supports pdf
Default handler: &latex;
        , Xe
Default handler: &latex;
         and Lua
Default handler: &latex;
        . The
        <code>
          polyglossia
        </code>
         package provides similar support with the latter two engines.
      </para>
      <para>
        This section does not cover that support. It only lists the core
Default handler: &latex;
         commands for creating accented characters. The
        <code>
          \capital...
        </code>
         commands shown here produce alternative forms for use with capital letters. These are not available with OT1.
      </para>
      <para>
        Below, to make them easier to find, the accents are all illustrated with lowercase
        <samp>
          o
        </samp>
        .
      </para>
      <findex index="fn" spaces=" ">
        <indexterm index="fn" number="1101" mergedindex="cp">
          \i
          <r>
            (dotless i)
          </r>
        </indexterm>
      </findex>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="1084">
          dotless i
        </indexterm>
      </cindex>
      <para>
        Note that
        <code>
          \i
        </code>
         produces a dotless i,
Default handler: <!-- c @dotless{i}, -->
        <findex index="fn" spaces=" ">
          <indexterm index="fn" number="1102" mergedindex="cp">
            \j
            <r>
              (dotless j)
            </r>
          </indexterm>
        </findex>
        <cindex index="cp" spaces=" ">
          <indexterm index="cp" number="1085">
            dotless j
          </indexterm>
        </cindex>
         and
        <code>
          \j
        </code>
         produces a dotless j.
Default handler: <!-- c @dotless{j}. -->
         These are often used in place of their dotted counterparts when they are accented.
      </para>
      <table commandarg="code" spaces=" " endspaces=" ">
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                \
                "
              </itemformat>
            </item>
            <itemx spaces=" ">
              <itemformat command="code">
                \capitaldieresis
              </itemformat>
            </itemx>
          </tableterm>
          <tableitem>
            <findex index="fn" spaces=" ">
              <indexterm index="fn" number="1103" mergedindex="cp">
                \
                "
                <r>
                  (umlaut accent)
                </r>
              </indexterm>
            </findex>
            <findex index="fn" spaces=" ">
              <indexterm index="fn" number="1104" mergedindex="cp">
                \capitaldieresis
              </indexterm>
            </findex>
            <cindex index="cp" spaces=" ">
              <indexterm index="cp" number="1086">
                umlaut accent
              </indexterm>
            </cindex>
            <cindex index="cp" spaces=" ">
              <indexterm index="cp" number="1087">
                dieresis accent
              </indexterm>
            </cindex>
            <para>
              <accent type="uml">
                o
              </accent>
               Umlaut (dieresis).
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                \'
              </itemformat>
            </item>
            <itemx spaces=" ">
              <itemformat command="code">
                \capitalacute
              </itemformat>
            </itemx>
          </tableterm>
          <tableitem>
            <findex index="fn" spaces=" ">
              <indexterm index="fn" number="1105" mergedindex="cp">
                \'
                <r>
                  (acute accent)
                </r>
              </indexterm>
            </findex>
            <findex index="fn" spaces=" ">
              <indexterm index="fn" number="1106" mergedindex="cp">
                \capitalacute
              </indexterm>
            </findex>
            <cindex index="cp" spaces=" ">
              <indexterm index="cp" number="1088">
                acute accent
              </indexterm>
            </cindex>
            <para>
              <accent type="acute">
                o
              </accent>
               Acute accent.
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                \.
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <findex index="fn" spaces=" ">
              <indexterm index="fn" number="1107" mergedindex="cp">
                \.
                <r>
                  (dot-over accent)
                </r>
              </indexterm>
            </findex>
            <cindex index="cp" spaces=" ">
              <indexterm index="cp" number="1089">
                dot accent
              </indexterm>
            </cindex>
            <cindex index="cp" spaces=" ">
              <indexterm index="cp" number="1090">
                dot-over accent
              </indexterm>
            </cindex>
            <para>
              <accent type="dotaccent">
                o
              </accent>
               Dot accent.
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                \=
              </itemformat>
            </item>
            <itemx spaces=" ">
              <itemformat command="code">
                \capitalmacron
              </itemformat>
            </itemx>
          </tableterm>
          <tableitem>
            <findex index="fn" spaces=" ">
              <indexterm index="fn" number="1108" mergedindex="cp">
                \=
                <r>
                  (macron accent)
                </r>
              </indexterm>
            </findex>
            <findex index="fn" spaces=" ">
              <indexterm index="fn" number="1109" mergedindex="cp">
                \capitalmacron
              </indexterm>
            </findex>
            <cindex index="cp" spaces=" ">
              <indexterm index="cp" number="1091">
                macron accent
              </indexterm>
            </cindex>
            <cindex index="cp" spaces=" ">
              <indexterm index="cp" number="1092">
                overbar accent
              </indexterm>
            </cindex>
            <cindex index="cp" spaces=" ">
              <indexterm index="cp" number="1093">
                bar-over accent
              </indexterm>
            </cindex>
            <para>
              <accent type="macr">
                o
              </accent>
               Macron (overbar) accent.
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                \^
              </itemformat>
            </item>
            <itemx spaces=" ">
              <itemformat command="code">
                \capitalcircumflex
              </itemformat>
            </itemx>
          </tableterm>
          <tableitem>
            <findex index="fn" spaces=" ">
              <indexterm index="fn" number="1110" mergedindex="cp">
                \^
                <r>
                  (circumflex accent)
                </r>
              </indexterm>
            </findex>
            <findex index="fn" spaces=" ">
              <indexterm index="fn" number="1111" mergedindex="cp">
                \capitalcircumflex
              </indexterm>
            </findex>
            <cindex index="cp" spaces=" ">
              <indexterm index="cp" number="1094">
                circumflex accent
              </indexterm>
            </cindex>
            <cindex index="cp" spaces=" ">
              <indexterm index="cp" number="1095">
                hat accent
              </indexterm>
            </cindex>
            <para>
              <accent type="circ">
                o
              </accent>
               Circumflex (hat) accent.
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                \`
              </itemformat>
            </item>
            <itemx spaces=" ">
              <itemformat command="code">
                \capitalgrave
              </itemformat>
            </itemx>
          </tableterm>
          <tableitem>
            <findex index="fn" spaces=" ">
              <indexterm index="fn" number="1112" mergedindex="cp">
                \`
                <r>
                  (grave accent)
                </r>
              </indexterm>
            </findex>
            <findex index="fn" spaces=" ">
              <indexterm index="fn" number="1113" mergedindex="cp">
                \capitalgrave
              </indexterm>
            </findex>
            <cindex index="cp" spaces=" ">
              <indexterm index="cp" number="1096">
                grave accent
              </indexterm>
            </cindex>
            <para>
              <accent type="grave">
                o
              </accent>
               Grave accent.
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                \~
              </itemformat>
            </item>
            <itemx spaces=" ">
              <itemformat command="code">
                \capitaltilde
              </itemformat>
            </itemx>
          </tableterm>
          <tableitem>
            <findex index="fn" spaces=" ">
              <indexterm index="fn" number="1114" mergedindex="cp">
                \~
                <r>
                  (tilde accent)
                </r>
              </indexterm>
            </findex>
            <findex index="fn" spaces=" ">
              <indexterm index="fn" number="1115" mergedindex="cp">
                \capitaltilde
              </indexterm>
            </findex>
            <cindex index="cp" spaces=" ">
              <indexterm index="cp" number="1097">
                tilde accent
              </indexterm>
            </cindex>
            <para>
              <accent type="tilde">
                n
              </accent>
               Tilde accent.
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                \b
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <findex index="fn" spaces=" ">
              <indexterm index="fn" number="1116" mergedindex="cp">
                \b
                <r>
                  (bar-under accent)
                </r>
              </indexterm>
            </findex>
            <cindex index="cp" spaces=" ">
              <indexterm index="cp" number="1098">
                bar-under accent
              </indexterm>
            </cindex>
            <para>
              <accent type="ubaraccent">
                o
              </accent>
               Bar accent underneath.
            </para>
            <findex index="fn" spaces=" ">
              <indexterm index="fn" number="1117" mergedindex="cp">
                \underbar
              </indexterm>
            </findex>
            <cindex index="cp" spaces=" ">
              <indexterm index="cp" number="1099">
                underbar
              </indexterm>
            </cindex>
            <para>
              Related to this,
              <code>
                \underbar
Default handler: &lbrace;
                <var>
                  text
                </var>
Default handler: &rbrace;
              </code>
               produces a bar under
              <var>
                text
              </var>
              . The argument is always processed in LR mode (
              <pxref label="Modes">
                <xrefnodename>
                  Modes
                </xrefnodename>
              </pxref>
              ). The bar is always a fixed position under the baseline, thus crossing through descenders. See also
              <code>
                \underline
              </code>
               in
              <ref label="Over_002d-and-Underlining">
                <xrefnodename>
                  Over- and Underlining
                </xrefnodename>
              </ref>
              .
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                \c
              </itemformat>
            </item>
            <itemx spaces=" ">
              <itemformat command="code">
                \capitalcedilla
              </itemformat>
            </itemx>
          </tableterm>
          <tableitem>
            <findex index="fn" spaces=" ">
              <indexterm index="fn" number="1118" mergedindex="cp">
                \c
                <r>
                  (cedilla accent)
                </r>
              </indexterm>
            </findex>
            <findex index="fn" spaces=" ">
              <indexterm index="fn" number="1119" mergedindex="cp">
                \capitalcedilla
              </indexterm>
            </findex>
            <cindex index="cp" spaces=" ">
              <indexterm index="cp" number="1100">
                cedilla accent
              </indexterm>
            </cindex>
            <para>
              <accent type="cedil">
                c
              </accent>
               Cedilla accent underneath.
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                \d
              </itemformat>
            </item>
            <itemx spaces=" ">
              <itemformat command="code">
                \capitaldotaccent
              </itemformat>
            </itemx>
          </tableterm>
          <tableitem>
            <findex index="fn" spaces=" ">
              <indexterm index="fn" number="1120" mergedindex="cp">
                \d
                <r>
                  (dot-under accent)
                </r>
              </indexterm>
            </findex>
            <findex index="fn" spaces=" ">
              <indexterm index="fn" number="1121" mergedindex="cp">
                \capitaldotaccent
              </indexterm>
            </findex>
            <cindex index="cp" spaces=" ">
              <indexterm index="cp" number="1101">
                dot-under accent
              </indexterm>
            </cindex>
            <para>
              <accent type="udotaccent">
                o
              </accent>
               Dot accent underneath.
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                \H
              </itemformat>
            </item>
            <itemx spaces=" ">
              <itemformat command="code">
                \capitalhungarumlaut
              </itemformat>
            </itemx>
          </tableterm>
          <tableitem>
            <findex index="fn" spaces=" ">
              <indexterm index="fn" number="1122" mergedindex="cp">
                \H
                <r>
                  (Hungarian umlaut accent)
                </r>
              </indexterm>
            </findex>
            <findex index="fn" spaces=" ">
              <indexterm index="fn" number="1123" mergedindex="cp">
                \capitalhungarumlaut
              </indexterm>
            </findex>
            <cindex index="cp" spaces=" ">
              <indexterm index="cp" number="1102">
                hungarian umlaut accent
              </indexterm>
            </cindex>
            <para>
              <accent type="doubleacute">
                o
              </accent>
               Long Hungarian umlaut accent.
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                \k
              </itemformat>
            </item>
            <itemx spaces=" ">
              <itemformat command="code">
                \capitalogonek
              </itemformat>
            </itemx>
          </tableterm>
          <tableitem>
            <findex index="fn" spaces=" ">
              <indexterm index="fn" number="1124" mergedindex="cp">
                \k
                <r>
                  (ogonek)
                </r>
              </indexterm>
            </findex>
            <findex index="fn" spaces=" ">
              <indexterm index="fn" number="1125" mergedindex="cp">
                \capitalogonek
              </indexterm>
            </findex>
            <cindex index="cp" spaces=" ">
              <indexterm index="cp" number="1103">
                ogonek
              </indexterm>
            </cindex>
            <para>
              <accent type="ogon">
                o
              </accent>
               Ogonek. Not available in the OT1 encoding.
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                \r
              </itemformat>
            </item>
            <itemx spaces=" ">
              <itemformat command="code">
                \capitalring
              </itemformat>
            </itemx>
          </tableterm>
          <tableitem>
            <findex index="fn" spaces=" ">
              <indexterm index="fn" number="1126" mergedindex="cp">
                \r
                <r>
                  (ring accent)
                </r>
              </indexterm>
            </findex>
            <findex index="fn" spaces=" ">
              <indexterm index="fn" number="1127" mergedindex="cp">
                \capitalring
              </indexterm>
            </findex>
            <cindex index="cp" spaces=" ">
              <indexterm index="cp" number="1104">
                ring accent
              </indexterm>
            </cindex>
            <para>
              <accent type="ring">
                o
              </accent>
               Ring accent.
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                \t
              </itemformat>
            </item>
            <itemx spaces=" ">
              <itemformat command="code">
                \capitaltie
              </itemformat>
            </itemx>
            <itemx spaces=" ">
              <itemformat command="code">
                \newtie
              </itemformat>
            </itemx>
            <itemx spaces=" ">
              <itemformat command="code">
                \capitalnewtie
              </itemformat>
            </itemx>
          </tableterm>
          <tableitem>
            <findex index="fn" spaces=" ">
              <indexterm index="fn" number="1128" mergedindex="cp">
                \t
                <r>
                  (tie-after accent)
                </r>
              </indexterm>
            </findex>
            <findex index="fn" spaces=" ">
              <indexterm index="fn" number="1129" mergedindex="cp">
                \capitaltie
              </indexterm>
            </findex>
            <findex index="fn" spaces=" ">
              <indexterm index="fn" number="1130" mergedindex="cp">
                \newtie
              </indexterm>
            </findex>
            <findex index="fn" spaces=" ">
              <indexterm index="fn" number="1131" mergedindex="cp">
                \capitalnewtie
              </indexterm>
            </findex>
            <cindex index="cp" spaces=" ">
              <indexterm index="cp" number="1105">
                tie-after accent
              </indexterm>
            </cindex>
            <para>
              Tie-after accent (used for transliterating from Cyrillic, such as in the ALA-LC romanization). It expects that the argument has two characters. The
              <code>
                \newtie
              </code>
               form is centered in its box.
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                \u
              </itemformat>
            </item>
            <itemx spaces=" ">
              <itemformat command="code">
                \capitalbreve
              </itemformat>
            </itemx>
          </tableterm>
          <tableitem>
            <findex index="fn" spaces=" ">
              <indexterm index="fn" number="1132" mergedindex="cp">
                \u
                <r>
                  (breve accent)
                </r>
              </indexterm>
            </findex>
            <findex index="fn" spaces=" ">
              <indexterm index="fn" number="1133" mergedindex="cp">
                \capitalbreve
              </indexterm>
            </findex>
            <cindex index="cp" spaces=" ">
              <indexterm index="cp" number="1106">
                breve accent
              </indexterm>
            </cindex>
            <para>
              <accent type="breve">
                o
              </accent>
               Breve accent.
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                \v
              </itemformat>
            </item>
            <itemx spaces=" ">
              <itemformat command="code">
                \capitalcaron
              </itemformat>
            </itemx>
          </tableterm>
          <tableitem>
            <findex index="fn" spaces=" ">
              <indexterm index="fn" number="1134" mergedindex="cp">
                \v
                <r>
                  (breve accent)
                </r>
              </indexterm>
            </findex>
            <findex index="fn" spaces=" ">
              <indexterm index="fn" number="1135" mergedindex="cp">
                \capitalcaron
              </indexterm>
            </findex>
            <cindex index="cp" spaces=" ">
              <indexterm index="cp" number="1107">
                hacek accent
              </indexterm>
            </cindex>
            <cindex index="cp" spaces=" ">
              <indexterm index="cp" number="1108">
                check accent
              </indexterm>
            </cindex>
            <cindex index="cp" spaces=" ">
              <indexterm index="cp" number="1109">
                caron accent
              </indexterm>
            </cindex>
            <para>
              <accent type="caron">
                o
              </accent>
               H
              <accent type="acute" bracketed="off">
                a
              </accent>
              <accent type="caron">
                c
              </accent>
              ek (check, caron) accent.
            </para>
          </tableitem>
        </tableentry>
      </table>
      <menu endspaces=" ">
        <menuentry>
          <menuleadingtext>
            *
          </menuleadingtext>
          <menunode>
            \accent
          </menunode>
          <menuseparator>
            ::
          </menuseparator>
          <menudescription>
            <pre xml:space="preserve">
              Low level command to produce an accented character.
            </pre>
          </menudescription>
        </menuentry>
      </menu>
      <node name="_005caccent" spaces=" ">
        <nodename>
          \accent
        </nodename>
        <nodeup automatic="on">
          Accents
        </nodeup>
      </node>
      <subsection spaces=" ">
        <sectiontitle>
          <code>
            \accent
          </code>
        </sectiontitle>
        <findex index="fn" spaces=" ">
          <indexterm index="fn" number="1136" mergedindex="cp">
            \accent
          </indexterm>
        </findex>
        <para>
          Synopsis:
        </para>
        <example endspaces=" ">
          <pre xml:space="preserve">
            \accent
            <var>
              number
            </var>
            <var>
              character
            </var>
          </pre>
        </example>
        <para>
          A
Default handler: &tex;
           primitive command used to generate accented characters from accent marks and letters. The accent mark is selected by
          <var>
            number
          </var>
          , a numeric argument, followed by a space and then a
          <var>
            character
          </var>
           argument to construct the accented character in the current font.
        </para>
        <para>
          These are accented
          <samp>
            e
          </samp>
           characters.
        </para>
        <example endspaces=" ">
          <pre xml:space="preserve">
            \accent18 e \accent20 e \accent21 e \accent22 e \accent23 e
          </pre>
        </example>
        <noindent/>
        <para>
          The first is a grave, the second a caron, the third a breve, the fourth a macron, and the fifth a ring above.
        </para>
        <para>
          The position of the accent is determined by the font designer and so the outcome of
          <code>
            \accent
          </code>
           use may differ between fonts. In
Default handler: &latex;
           it is desirable to have glyphs for accented characters rather than building them using
          <code>
            \accent
          </code>
          . Using glyphs that already contain the accented characters (as in T1 encoding) allows correct hyphenation whereas
          <code>
            \accent
          </code>
           disables hyphenation (specifically with OT1 font encoding where accented glyphs are absent).
        </para>
        <para>
          There can be an optional font change between
          <var>
            number
          </var>
           and
          <var>
            character
          </var>
          . Note also that this command sets the
          <code>
            \spacefactor
          </code>
           to 1000 (
          <pxref label="_005cspacefactor">
            <xrefnodename>
              \spacefactor
            </xrefnodename>
          </pxref>
          ).
        </para>
        <para>
          An unavoidable characteristic of some Cyrillic letters and the majority of accented Cyrillic letters is that they must be assembled from multiple elements (accents, modifiers, etc.) while
          <code>
            \accent
          </code>
           provides for a single accent mark and a single letter combination. There are also cases where accents must appear between letters that \accent does not support. Still other cases exist where the letters I and J have dots above their lowercase counterparts that conflict with dotted accent marks. The use of
          <code>
            \accent
          </code>
           in these cases will not work as it cannot analyze upper/lower case.
        </para>
      </subsection>
    </section>
    <node name="Additional-Latin-letters" spaces=" ">
      <nodename>
        Additional Latin letters
      </nodename>
      <nodenext automatic="on">
        inputenc package
      </nodenext>
      <nodeprev automatic="on">
        Accents
      </nodeprev>
      <nodeup automatic="on">
        Special insertions
      </nodeup>
    </node>
    <section spaces=" ">
      <sectiontitle>
        Additional Latin letters
      </sectiontitle>
      <anchor name="Non_002dEnglish-characters">
        Non-English characters
      </anchor>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="1110">
          Latin letters, additional
        </indexterm>
      </cindex>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="1111">
          letters, additional Latin
        </indexterm>
      </cindex>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="1112">
          extended Latin
        </indexterm>
      </cindex>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="1113">
          special characters
        </indexterm>
      </cindex>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="1114">
          non-English characters
        </indexterm>
      </cindex>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="1115">
          characters, non-English
        </indexterm>
      </cindex>
      <para>
        Here are the basic
Default handler: &latex;
         commands for inserting letters beyond A
Default handler: &textndash;
        Z that extend the Latin alphabet, used primarily in languages other than English.
      </para>
      <table commandarg="code" spaces=" " endspaces=" ">
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                \aa
              </itemformat>
            </item>
            <itemx spaces=" ">
              <itemformat command="code">
                \AA
              </itemformat>
            </itemx>
          </tableterm>
          <tableitem>
            <findex index="fn" spaces=" ">
              <indexterm index="fn" number="1137" mergedindex="cp">
                \aa
                <r>
                  (
Default handler: &aring;
                  )
                </r>
              </indexterm>
            </findex>
            <findex index="fn" spaces=" ">
              <indexterm index="fn" number="1138" mergedindex="cp">
                \AA
                <r>
                  (
Default handler: &Aring;
                  )
                </r>
              </indexterm>
            </findex>
            <cindex index="cp" spaces=" ">
              <indexterm index="cp" number="1116">
                aring
              </indexterm>
            </cindex>
            <paraDefault handler: &aring;
>
               and
Default handler: &Aring;
              .
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                \ae
              </itemformat>
            </item>
            <itemx spaces=" ">
              <itemformat command="code">
                \AE
              </itemformat>
            </itemx>
          </tableterm>
          <tableitem>
            <findex index="fn" spaces=" ">
              <indexterm index="fn" number="1139" mergedindex="cp">
                \ae
                <r>
                  (
Default handler: &aelig;
                  )
                </r>
              </indexterm>
            </findex>
            <findex index="fn" spaces=" ">
              <indexterm index="fn" number="1140" mergedindex="cp">
                \AE
                <r>
                  (
Default handler: &AElig;
                  )
                </r>
              </indexterm>
            </findex>
            <cindex index="cp" spaces=" ">
              <indexterm index="cp" number="1117">
                ae ligature
              </indexterm>
            </cindex>
            <paraDefault handler: &aelig;
>
               and
Default handler: &AElig;
              .
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                \dh
              </itemformat>
            </item>
            <itemx spaces=" ">
              <itemformat command="code">
                \DH
              </itemformat>
            </itemx>
          </tableterm>
          <tableitem>
            <findex index="fn" spaces=" ">
              <indexterm index="fn" number="1141" mergedindex="cp">
                \dh
                <r>
                  (
Default handler: &eth;
                  )
                </r>
              </indexterm>
            </findex>
            <findex index="fn" spaces=" ">
              <indexterm index="fn" number="1142" mergedindex="cp">
                \DH
                <r>
                  (
Default handler: &ETH;
                  )
                </r>
              </indexterm>
            </findex>
            <cindex index="cp" spaces=" ">
              <indexterm index="cp" number="1118">
                Icelandic eth
              </indexterm>
            </cindex>
            <cindex index="cp" spaces=" ">
              <indexterm index="cp" number="1119">
                eth, Icelandic letter
              </indexterm>
            </cindex>
            <para>
              Icelandic letter eth:
Default handler: &eth;
               and
Default handler: &ETH;
              . Not available with
              <sc>
                OT1
              </sc>
               encoding, you need the
              <file>
                fontenc
              </file>
               package to select an alternate font encoding, such as
              <sc>
                T1
              </sc>
              .
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                \dj
              </itemformat>
            </item>
            <itemx spaces=" ">
              <itemformat command="code">
                \DJ
              </itemformat>
            </itemx>
          </tableterm>
          <tableitem>
            <findex index="fn" spaces=" ">
              <indexterm index="fn" number="1143" mergedindex="cp">
                \dj
              </indexterm>
            </findex>
            <findex index="fn" spaces=" ">
              <indexterm index="fn" number="1144" mergedindex="cp">
                \DJ
              </indexterm>
            </findex>
            <para>
              Crossed d and D, a.k.a.
Default handler: &noeos;
               capital and small letter d with stroke. Not available with
              <sc>
                OT1
              </sc>
               encoding, you need the
              <file>
                fontenc
              </file>
               package to select an alternate font encoding, such as
              <sc>
                T1
              </sc>
              .
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                \ij
              </itemformat>
            </item>
            <itemx spaces=" ">
              <itemformat command="code">
                \IJ
              </itemformat>
            </itemx>
          </tableterm>
          <tableitem>
            <findex index="fn" spaces=" ">
              <indexterm index="fn" number="1145" mergedindex="cp">
                \ij
                <r>
                  (ij)
                </r>
              </indexterm>
            </findex>
            <findex index="fn" spaces=" ">
              <indexterm index="fn" number="1146" mergedindex="cp">
                \IJ
                <r>
                  (IJ)
                </r>
              </indexterm>
            </findex>
            <cindex index="cp" spaces=" ">
              <indexterm index="cp" number="1120">
                ij letter, Dutch
              </indexterm>
            </cindex>
            <para>
              ij and IJ (except somewhat closer together than appears here).
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                \l
              </itemformat>
            </item>
            <itemx spaces=" ">
              <itemformat command="code">
                \L
              </itemformat>
            </itemx>
          </tableterm>
          <tableitem>
            <findex index="fn" spaces=" ">
              <indexterm index="fn" number="1147" mergedindex="cp">
                \l
                <r>
                  (
Default handler: &lslash;
                  )
                </r>
              </indexterm>
            </findex>
            <findex index="fn" spaces=" ">
              <indexterm index="fn" number="1148" mergedindex="cp">
                \L
                <r>
                  (
Default handler: &Lslash;
                  )
                </r>
              </indexterm>
            </findex>
            <cindex index="cp" spaces=" ">
              <indexterm index="cp" number="1121">
                polish l
              </indexterm>
            </cindex>
            <paraDefault handler: &lslash;
>
               and
Default handler: &Lslash;
              .
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                \ng
              </itemformat>
            </item>
            <itemx spaces=" ">
              <itemformat command="code">
                \NG
              </itemformat>
            </itemx>
          </tableterm>
          <tableitem>
            <findex index="fn" spaces=" ">
              <indexterm index="fn" number="1149" mergedindex="cp">
                \ng
              </indexterm>
            </findex>
            <findex index="fn" spaces=" ">
              <indexterm index="fn" number="1150" mergedindex="cp">
                \NG
              </indexterm>
            </findex>
            <para>
              Lappish letter eng, also used in phonetics.
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                \o
              </itemformat>
            </item>
            <itemx spaces=" ">
              <itemformat command="code">
                \O
              </itemformat>
            </itemx>
          </tableterm>
          <tableitem>
            <findex index="fn" spaces=" ">
              <indexterm index="fn" number="1151" mergedindex="cp">
                \o
                <r>
                  (
Default handler: &oslash;
                  )
                </r>
              </indexterm>
            </findex>
            <findex index="fn" spaces=" ">
              <indexterm index="fn" number="1152" mergedindex="cp">
                \O
                <r>
                  (
Default handler: &Oslash;
                  )
                </r>
              </indexterm>
            </findex>
            <cindex index="cp" spaces=" ">
              <indexterm index="cp" number="1122">
                oslash
              </indexterm>
            </cindex>
            <paraDefault handler: &oslash;
>
               and
Default handler: &Oslash;
              .
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                \oe
              </itemformat>
            </item>
            <itemx spaces=" ">
              <itemformat command="code">
                \OE
              </itemformat>
            </itemx>
          </tableterm>
          <tableitem>
            <findex index="fn" spaces=" ">
              <indexterm index="fn" number="1153" mergedindex="cp">
                \oe
                <r>
                  (
Default handler: &oelig;
                  )
                </r>
              </indexterm>
            </findex>
            <findex index="fn" spaces=" ">
              <indexterm index="fn" number="1154" mergedindex="cp">
                \OE
                <r>
                  (
Default handler: &OElig;
                  )
                </r>
              </indexterm>
            </findex>
            <cindex index="cp" spaces=" ">
              <indexterm index="cp" number="1123">
                oe ligature
              </indexterm>
            </cindex>
            <paraDefault handler: &oelig;
>
               and
Default handler: &OElig;
              .
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                \ss
              </itemformat>
            </item>
            <itemx spaces=" ">
              <itemformat command="code">
                \SS
              </itemformat>
            </itemx>
          </tableterm>
          <tableitem>
            <findex index="fn" spaces=" ">
              <indexterm index="fn" number="1155" mergedindex="cp">
                \ss
                <r>
                  (
Default handler: &szlig;
                  )
                </r>
              </indexterm>
            </findex>
            <findex index="fn" spaces=" ">
              <indexterm index="fn" number="1156" mergedindex="cp">
                \SS
                <r>
                  (SS)
                </r>
              </indexterm>
            </findex>
            <cindex index="cp" spaces=" ">
              <indexterm index="cp" number="1124">
                es-zet German letter
              </indexterm>
            </cindex>
            <cindex index="cp" spaces=" ">
              <indexterm index="cp" number="1125">
                sharp S letters
              </indexterm>
            </cindex>
            <paraDefault handler: &szlig;
>
               and SS.
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                \th
              </itemformat>
            </item>
            <itemx spaces=" ">
              <itemformat command="code">
                \TH
              </itemformat>
            </itemx>
          </tableterm>
          <tableitem>
            <findex index="fn" spaces=" ">
              <indexterm index="fn" number="1157" mergedindex="cp">
                \th
                <r>
                  (
Default handler: &thorn;
                  )
                </r>
              </indexterm>
            </findex>
            <findex index="fn" spaces=" ">
              <indexterm index="fn" number="1158" mergedindex="cp">
                \TH
                <r>
                  (
Default handler: &THORN;
                  )
                </r>
              </indexterm>
            </findex>
            <cindex index="cp" spaces=" ">
              <indexterm index="cp" number="1126">
                Icelandic thorn
              </indexterm>
            </cindex>
            <cindex index="cp" spaces=" ">
              <indexterm index="cp" number="1127">
                thorn, Icelandic letter
              </indexterm>
            </cindex>
            <para>
              Icelandic letter thorn:
Default handler: &thorn;
               and
Default handler: &THORN;
              . Not available with
              <sc>
                OT1
              </sc>
               encoding, you need the
              <file>
                fontenc
              </file>
               package to select an alternate font encoding, such as
              <sc>
                T1
              </sc>
              .
            </para>
          </tableitem>
        </tableentry>
      </table>
    </section>
    <node name="inputenc-package" spaces=" ">
      <nodename>
        inputenc package
      </nodename>
      <nodenext automatic="on">
        \rule
      </nodenext>
      <nodeprev automatic="on">
        Additional Latin letters
      </nodeprev>
      <nodeup automatic="on">
        Special insertions
      </nodeup>
    </node>
    <section spaces=" ">
      <sectiontitle>
        <code>
          inputenc
        </code>
         package
      </sectiontitle>
      <findex index="fn" spaces=" ">
        <indexterm index="fn" number="1159" mergedindex="cp">
          inputenc
        </indexterm>
      </findex>
      <para>
        Synopsis:
      </para>
      <example endspaces=" ">
        <pre xml:space="preserve">
          \usepackage[
          <var>
            encoding-name
          </var>
          ]
Default handler: &lbrace;
          inputenc
Default handler: &rbrace;
        </pre>
      </example>
      <para>
        Declare the input file
Default handler: &textrsquo;
        s text encoding to be
        <var>
          encoding-name
        </var>
        . (For basic background,
        <pxref label="Input-encodings">
          <xrefnodename>
            Input encodings
          </xrefnodename>
        </pxref>
        ). The default, if this package is not loaded, is UTF-8. Technically, specifying the encoding name is optional, but in practice it is not useful to omit it.
      </para>
      <para>
        The
        <code>
          inputenc
        </code>
         package tells
Default handler: &latex;
         what encoding is used. For instance, the following command explicitly says that the input file is UTF-8 (note the lack of a dash).
      </para>
      <example endspaces=" ">
        <pre xml:space="preserve">
          \usepackage[utf8]
Default handler: &lbrace;
          inputenc
Default handler: &rbrace;
        </pre>
      </example>
      <para>
        The most common values for
        <var>
          encoding-name
        </var>
         are:
        <code>
          ascii
        </code>
        ,
        <code>
          latin1
        </code>
        ,
        <code>
          latin2
        </code>
        ,
        <code>
          latin3
        </code>
        ,
        <code>
          latin4
        </code>
        ,
        <code>
          latin5
        </code>
        ,
        <code>
          latin9
        </code>
        ,
        <code>
          latin10
        </code>
        ,
        <code>
          utf8
        </code>
        .
      </para>
      <para>
        Caution: use
        <code>
          inputenc
        </code>
         only with the pdf
Default handler: &tex;
         engine (
        <pxref label="TeX-engines">
          <xrefnodenameDefault handler: &tex;
>
             engines
          </xrefnodename>
        </pxref>
        ); with
        <command>
          xelatex
        </command>
         or
        <command>
          lualatex
        </command>
        , declaring a non-UTF-8 encoding with
        <code>
          inputenc
        </code>
        , such as
        <code>
          latin1
        </code>
        , will get the error
        <code>
          inputenc is not designed for xetex or luatex
        </code>
        .
      </para>
      <para>
        An
        <code>
          inputenc
        </code>
         package error such as
        <code>
          Invalid UTF-8 byte
          "
          96
        </code>
         means that some of the material in the input file does not follow the encoding scheme. Often these errors come from copying material from a document that uses a different encoding than the input file. The simplest solution is often to replace the non-UTF-8 character with a UTF-8 or
Default handler: &latex;
         equivalent.
      </para>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="1128">
          <r>
            package
          </r>
          ,
          <code>
            luainputenc
          </code>
        </indexterm>
      </cindex>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="1129">
          <code>
            luainputenc
          </code>
          <r>
            package
          </r>
        </indexterm>
      </cindex>
      <findex index="fn" spaces=" ">
        <indexterm index="fn" number="1160" mergedindex="cp">
          \XeTeXinputencoding
        </indexterm>
      </findex>
      <findex index="fn" spaces=" ">
        <indexterm index="fn" number="1161" mergedindex="cp">
          \XeTeXdefaultencoding
        </indexterm>
      </findex>
      <para>
        If you need to process a non-UTF-8 document with Lua
Default handler: &tex;
        , you can use the
        <code>
          luainputenc
        </code>
         package (
        <url>
          <urefurl>
            https://ctan.org/pkg/luainputenc
          </urefurl>
        </url>
        ). With Xe
Default handler: &tex;
        , the
        <code>
          \XeTeXinputencoding
        </code>
         and
        <code>
          \XeTeXdefaultencoding
        </code>
         primitives can be used (for an explanation and examples, see
        <url>
          <urefurl>
            https://tex.stackexchange.com/questions/324948
          </urefurl>
        </url>
        ).
      </para>
      <pindex index="pg" spaces=" ">
        <indexterm index="pg" number="1">
          recode
          <r>
            to change character encoding
          </r>
        </indexterm>
      </pindex>
      <pindex index="pg" spaces=" ">
        <indexterm index="pg" number="2">
          iconv
          <r>
            to change character encoding
          </r>
        </indexterm>
      </pindex>
      <para>
        It
Default handler: &textrsquo;
        s also possible to re-encode a document from an 8-bit encoding to UTF-8 outside of
Default handler: &tex;
        , using system utilities. For example,
        <samp>
          recode latin1..utf8
        </samp>
         or
        <samp>
          iconv -f latin1 -t utf8
        </samp>
        .
      </para>
      <findex index="fn" spaces=" ">
        <indexterm index="fn" number="1162" mergedindex="cp">
          \inputencoding
        </indexterm>
      </findex>
      <anchor name="_005cinputencoding">
        \inputencoding
      </anchor>
      <para>
        In a few documents, such as a collection of journal articles from a variety of authors, changing the encoding in mid-document may be necessary. You can use the command
        <code>
          \inputencoding
Default handler: &lbrace;
          <var>
            encoding-name
          </var>
Default handler: &rbrace;
        </code>
         for this.
      </para>
    </section>
    <node name="_005crule" spaces=" ">
      <nodename>
        \rule
      </nodename>
      <nodenext automatic="on">
        \today
      </nodenext>
      <nodeprev automatic="on">
        inputenc package
      </nodeprev>
      <nodeup automatic="on">
        Special insertions
      </nodeup>
    </node>
    <section spaces=" ">
      <sectiontitle>
        <code>
          \rule
        </code>
      </sectiontitle>
      <findex index="fn" spaces=" ">
        <indexterm index="fn" number="1163" mergedindex="cp">
          \rule
        </indexterm>
      </findex>
      <para>
        Synopsis, one of:
      </para>
      <example endspaces=" ">
        <pre xml:space="preserve">
          \rule
Default handler: &lbrace;
          <var>
            width
          </var>
Default handler: &rbrace;
Default handler: &lbrace;
          <var>
            thickness
          </var>
Default handler: &rbrace;
           \rule[
          <var>
            raise
          </var>
          ]
Default handler: &lbrace;
          <var>
            width
          </var>
Default handler: &rbrace;
Default handler: &lbrace;
          <var>
            thickness
          </var>
Default handler: &rbrace;
        </pre>
      </example>
      <para>
        Produce a
        <dfn>
          rule
        </dfn>
        , a filled-in rectangle.
      </para>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="1130">
          Halmos symbol
        </indexterm>
      </cindex>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="1131">
          tombstone
        </indexterm>
      </cindex>
      <para>
        This example produces a rectangular blob, sometimes called a Halmos symbol, or just
Default handler: &textldquo;
        qed
Default handler: &textrdquo;
        , often used to mark the end of a proof:
      </para>
      <example endspaces=" ">
        <pre xml:space="preserve">
          \newcommand
Default handler: &lbrace;
          \qedsymbol
Default handler: &rbrace;
Default handler: &lbrace;
          \rule
Default handler: &lbrace;
          0.4em
Default handler: &rbrace;
Default handler: &lbrace;
          2ex
Default handler: &rbrace;
Default handler: &rbrace;
        </pre>
      </example>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="1132">
          <r>
            package
          </r>
          ,
          <code>
            amsthm
          </code>
        </indexterm>
      </cindex>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="1133">
          <code>
            amsthm
          </code>
          <r>
            package
          </r>
        </indexterm>
      </cindex>
      <noindent/>
      <para>
        The
        <code>
          amsthm
        </code>
         package includes this command, with a somewhat different-looking symbol.
      </para>
      <para>
        The mandatory arguments give the horizontal
        <var>
          width
        </var>
         and vertical
        <var>
          thickness
        </var>
         of the rectangle. They are rigid lengths (
        <pxref label="Lengths">
          <xrefnodename>
            Lengths
          </xrefnodename>
        </pxref>
        ). The optional argument
        <var>
          raise
        </var>
         is also a rigid length, and tells
Default handler: &latex;
         how much to raise the rule above the baseline, or lower it if the length is negative.
      </para>
      <para>
        This produces a line, a rectangle that is wide but not tall.
      </para>
      <example endspaces=" ">
        <pre xml:space="preserve">
          \noindent\rule
Default handler: &lbrace;
          \textwidth
Default handler: &rbrace;
Default handler: &lbrace;
          0.4pt
Default handler: &rbrace;
        </pre>
      </example>
      <noindent/>
      <para>
        The line is the width of the page and 0.4
Default handler: &nbsp;
        points tall. This line thickness is common in
Default handler: &latex;
        .
      </para>
      <para>
        A rule that has zero width, or zero thickness, will not show up in the output, but can cause
Default handler: &latex;
         to change the output around it.
        <xref label="_005cstrut">
          <xrefnodename>
            \strut
          </xrefnodename>
        </xref>
        , for examples.
      </para>
    </section>
    <node name="_005ctoday" spaces=" ">
      <nodename>
        \today
      </nodename>
      <nodeprev automatic="on">
        \rule
      </nodeprev>
      <nodeup automatic="on">
        Special insertions
      </nodeup>
    </node>
    <section spaces=" ">
      <sectiontitle>
        <code>
          \today
        </code>
      </sectiontitle>
      <findex index="fn" spaces=" ">
        <indexterm index="fn" number="1164" mergedindex="cp">
          \today
        </indexterm>
      </findex>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="1134">
          date, today
Default handler: &textrsquo;
          s
        </indexterm>
      </cindex>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="1135">
          today
Default handler: &textrsquo;
          s date
        </indexterm>
      </cindex>
      <para>
        Synopsis:
      </para>
      <example endspaces=" ">
        <pre xml:space="preserve">
          \today
        </pre>
      </example>
      <para>
        Produce today
Default handler: &textrsquo;
        s date in the format
        <samp>
          <var>
            month
          </var>
          <var>
            dd
          </var>
          ,
          <var>
            yyyy
          </var>
        </samp>
        . An example of a date in that format is
        <samp>
          July 4, 1976
        </samp>
        .
      </para>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="1136">
          <r>
            package
          </r>
          ,
          <code>
            babel
          </code>
        </indexterm>
      </cindex>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="1137">
          <code>
            babel
          </code>
          <r>
            package
          </r>
        </indexterm>
      </cindex>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="1138">
          <r>
            package
          </r>
          ,
          <code>
            polyglossia
          </code>
        </indexterm>
      </cindex>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="1139">
          <code>
            polyglossia
          </code>
          <r>
            package
          </r>
        </indexterm>
      </cindex>
      <para>
        Multilingual packages such as
        <code>
          babel
        </code>
         or
        <code>
          polyglossia
        </code>
        , or classes such as
        <file>
          lettre
        </file>
        , will localize
        <code>
          \today
        </code>
        . For example, the following will output
        <samp>
          4 juillet 1976
        </samp>
        :
      </para>
      <example endspaces=" ">
        <pre xml:space="preserve">
          \year=1976 \month=7 \day=4 \documentclass
Default handler: &lbrace;
          minimal
Default handler: &rbrace;
           \usepackage[french]
Default handler: &lbrace;
          babel
Default handler: &rbrace;
           \begin
Default handler: &lbrace;
          document
Default handler: &rbrace;
           \today \end
Default handler: &lbrace;
          document
Default handler: &rbrace;
        </pre>
      </example>
      <noindent/>
      <para>
        <code>
          \today
        </code>
         uses the counters
        <code>
          \day
        </code>
        ,
        <code>
          \month
        </code>
        , and
        <code>
          \year
        </code>
         (
        <pxref label="_005cday-_0026-_005cmonth-_0026-_005cyear">
          <xrefnodename>
            \day
            &
             \month
            &
             \year
          </xrefnodename>
        </pxref>
        ).
      </para>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="1140">
          <r>
            package
          </r>
          ,
          <code>
            datetime
          </code>
        </indexterm>
      </cindex>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="1141">
          <code>
            datetime
          </code>
          <r>
            package
          </r>
        </indexterm>
      </cindex>
      <para>
        A number of package on CTAN work with dates. One is
        <code>
          datetime
        </code>
         package which can produce a wide variety of date formats, including ISO standards.
      </para>
      <para>
        The date is not updated as the
Default handler: &latex;
         process runs, so in principle the date could be incorrect by the time the program finishes.
      </para>
    </section>
  </chapter>
  <node name="Splitting-the-input" spaces=" ">
    <nodename>
      Splitting the input
    </nodename>
    <nodenext automatic="on">
      Front/back matter
    </nodenext>
    <nodeprev automatic="on">
      Special insertions
    </nodeprev>
    <nodeup automatic="on">
      Top
    </nodeup>
  </node>
  <chapter spaces=" ">
    <sectiontitle>
      Splitting the input
    </sectiontitle>
    <cindex index="cp" spaces=" ">
      <indexterm index="cp" number="1142">
        splitting the input file
      </indexterm>
    </cindex>
    <cindex index="cp" spaces=" ">
      <indexterm index="cp" number="1143">
        input file
      </indexterm>
    </cindex>
    <paraDefault handler: &latex;
>
       lets you split a large document into several smaller ones. This can simplify editing or allow multiple authors to work on the document. It can also speed processing.
    </para>
    <para>
      Regardless of how many separate files you use, there is always one
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="1144">
          root file
        </indexterm>
      </cindex>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="1145">
          file, root
        </indexterm>
      </cindex>
      <dfn>
        root file
      </dfn>
      , on which
Default handler: &latex;
       compilation starts. This shows such a file with five included files.
    </para>
    <example endspaces=" ">
      <pre xml:space="preserve">
        \documentclass
Default handler: &lbrace;
        book
Default handler: &rbrace;
         \includeonly
Default handler: &lbrace;
         % comment out lines below to omit compiling pref, chap1, chap2, append, bib
Default handler: &rbrace;
         \begin
Default handler: &lbrace;
        document
Default handler: &rbrace;
         \frontmatter \include
Default handler: &lbrace;
        pref
Default handler: &rbrace;
         \mainmatter \include
Default handler: &lbrace;
        chap1
Default handler: &rbrace;
         \include
Default handler: &lbrace;
        chap2
Default handler: &rbrace;
         \appendix \include
Default handler: &lbrace;
        append
Default handler: &rbrace;
         \backmatter \include
Default handler: &lbrace;
        bib
Default handler: &rbrace;
         \end
Default handler: &lbrace;
        document
Default handler: &rbrace;
      </pre>
    </example>
    <noindent/>
    <para>
      This will bring in material from
      <file>
        pref.tex
      </file>
      ,
      <file>
        chap1.tex
      </file>
      ,
      <file>
        chap2.tex
      </file>
      ,
      <file>
        append.tex
      </file>
      , and
      <file>
        bib.tex
      </file>
      . If you compile this file, and then comment out all of the lines inside
      <code>
        \includeonly
Default handler: &lbrace;
        ...
Default handler: &rbrace;
      </code>
       except for
      <code>
        chap1
      </code>
      , and compile again, then
Default handler: &latex;
       will only process the material in the first chapter. Thus, your output will appear more quickly and be shorter to print. However, the advantage of the
      <code>
        \includeonly
      </code>
       command is that
Default handler: &latex;
       will retain the page numbers and all of the cross reference information from the other parts of the document so these will appear in your output correctly.
    </para>
    <para>
      <xref label="Larger-book-template">
        <xrefnodename>
          Larger book template
        </xrefnodename>
      </xref>
      , for another example of
      <code>
        \includeonly
      </code>
      .
    </para>
    <menu endspaces=" ">
      <menuentry>
        <menuleadingtext>
          *
        </menuleadingtext>
        <menunode>
          \endinput
        </menunode>
        <menuseparator>
          ::
        </menuseparator>
        <menudescription>
          <pre xml:space="preserve">
            Stop including material from a file.
          </pre>
        </menudescription>
      </menuentry>
      <menuentry>
        <menuleadingtext>
          *
        </menuleadingtext>
        <menunode>
          \include
          &
           \includeonly
        </menunode>
        <menuseparator>
          ::
        </menuseparator>
        <menudescription>
          <pre xml:space="preserve">
            Conditionally include files.
          </pre>
        </menudescription>
      </menuentry>
      <menuentry>
        <menuleadingtext>
          *
        </menuleadingtext>
        <menunode>
          \input
        </menunode>
        <menuseparator>
          ::
        </menuseparator>
        <menudescription>
          <pre xml:space="preserve">
            Unconditionally include a file.
          </pre>
        </menudescription>
      </menuentry>
    </menu>
    <node name="_005cendinput" spaces=" ">
      <nodename>
        \endinput
      </nodename>
      <nodenext automatic="on">
        \include
        &
         \includeonly
      </nodenext>
      <nodeup automatic="on">
        Splitting the input
      </nodeup>
    </node>
    <section spaces=" ">
      <sectiontitle>
        <code>
          \endinput
        </code>
      </sectiontitle>
      <findex index="fn" spaces=" ">
        <indexterm index="fn" number="1165" mergedindex="cp">
          \endinput
        </indexterm>
      </findex>
      <para>
        Synopsis:
      </para>
      <example endspaces=" ">
        <pre xml:space="preserve">
          \endinput
        </pre>
      </example>
      <para>
        When you
        <code>
          \include
Default handler: &lbrace;
          filename
Default handler: &rbrace;
        </code>
        , inside
        <file>
          filename.tex
        </file>
         the material after
        <code>
          \endinput
        </code>
         will not be included. This command is optional; if
        <file>
          filename.tex
        </file>
         has no
        <code>
          \endinput
        </code>
         then
Default handler: &latex;
         will read all of the file.
      </para>
      <para>
        For example, suppose that a document
Default handler: &textrsquo;
        s root file has
        <code>
          \input
Default handler: &lbrace;
          chap1
Default handler: &rbrace;
        </code>
         and this is
        <file>
          chap1.tex
        </file>
        .
      </para>
      <example endspaces=" ">
        <pre xml:space="preserve">
          \chapter
Default handler: &lbrace;
          One
Default handler: &rbrace;
           This material will appear in the document. \endinput This will not appear.
        </pre>
      </example>
      <para>
        This can be useful for putting documentation or comments at the end of a file, or for avoiding junk characters that can be added if the file is transmitted in the body of an email. It is also useful for debugging: one strategy to localize errors is to put
        <code>
          \endinput
        </code>
         halfway through the included file and see if the error disappears. Now, knowing which half contains the error, moving
        <code>
          \endinput
        </code>
         to halfway through that area further narrows down the location. This process rapidly finds the offending line.
      </para>
      <para>
        After reading
        <code>
          \endinput
        </code>
        ,
Default handler: &latex;
         continues to read to the end of the line, so something can follow this command and be read nonetheless. This allows you, for instance, to close an
        <code>
          \if...
        </code>
         with a
        <code>
          \fi
        </code>
        .
      </para>
    </section>
    <node name="_005cinclude-_0026-_005cincludeonly" spaces=" ">
      <nodename>
        \include
        &
         \includeonly
      </nodename>
      <nodenext automatic="on">
        \input
      </nodenext>
      <nodeprev automatic="on">
        \endinput
      </nodeprev>
      <nodeup automatic="on">
        Splitting the input
      </nodeup>
    </node>
    <section spaces=" ">
      <sectiontitle>
        <code>
          \include
        </code>
        &
        <code>
          \includeonly
        </code>
      </sectiontitle>
      <anchor name="_005cinclude">
        \include
      </anchor>
      <anchor name="_005cincludeonly">
        \includeonly
      </anchor>
      <findex index="fn" spaces=" ">
        <indexterm index="fn" number="1166" mergedindex="cp">
          \include
        </indexterm>
      </findex>
      <findex index="fn" spaces=" ">
        <indexterm index="fn" number="1167" mergedindex="cp">
          \includeonly
        </indexterm>
      </findex>
      <para>
        Synopsis:
      </para>
      <example endspaces=" ">
        <pre xml:space="preserve">
          \includeonly
Default handler: &lbrace;
           % in document preamble ...
          <var>
            filename
          </var>
          , ...
Default handler: &rbrace;
           ... \include
Default handler: &lbrace;
          <var>
            filename
          </var>
Default handler: &rbrace;
           % in document body
        </pre>
      </example>
      <para>
        Bring material from the external file
        <file>
          <var>
            filename
          </var>
          .tex
        </file>
         into a
Default handler: &latex;
         document.
      </para>
      <para>
        The
        <code>
          \include
        </code>
         command does three things: it executes
        <code>
          \clearpage
        </code>
         (
        <pxref label="_005cclearpage-_0026-_005ccleardoublepage">
          <xrefnodename>
            \clearpage
            &
             \cleardoublepage
          </xrefnodename>
        </pxref>
        ), then it inputs the material from
        <file>
          <var>
            filename
          </var>
          .tex
        </file>
         into the document, and then it does another
        <code>
          \clearpage
        </code>
        . This command can only appear in the document body.
      </para>
      <para>
        The
        <code>
          \includeonly
        </code>
         command controls which files will be read by
Default handler: &latex;
         under subsequent
        <code>
          \include
        </code>
         commands. Its list of filenames is comma-separated. It must appear in the preamble or even earlier, e.g., the command line; it can
Default handler: &textrsquo;
        t appear in the document body.
      </para>
      <para>
        This example root document,
        <file>
          constitution.tex
        </file>
        , brings in three files,
        <file>
          preamble.tex
        </file>
        ,
        <file>
          articles.tex
        </file>
        , and
        <file>
          amendments.tex
        </file>
        .
      </para>
      <example endspaces=" ">
        <pre xml:space="preserve">
          \documentclass
Default handler: &lbrace;
          book
Default handler: &rbrace;
           \includeonly
Default handler: &lbrace;
           preamble, articles, amendments
Default handler: &rbrace;
           \begin
Default handler: &lbrace;
          document
Default handler: &rbrace;
           \include
Default handler: &lbrace;
          preamble
Default handler: &rbrace;
           \include
Default handler: &lbrace;
          articles
Default handler: &rbrace;
           \include
Default handler: &lbrace;
          amendments
Default handler: &rbrace;
           \end
Default handler: &lbrace;
          document
Default handler: &rbrace;
        </pre>
      </example>
      <noindent/>
      <para>
        The file
        <file>
          preamble.tex
        </file>
         contains no special code; you have just excerpted the chapter from
        <file>
          consitution.tex
        </file>
         and put it in a separate file just for editing convenience.
      </para>
      <example endspaces=" ">
        <pre xml:space="preserve">
          \chapter
Default handler: &lbrace;
          Preamble
Default handler: &rbrace;
           We the People of the United States, in Order to form a more perfect Union, ...
        </pre>
      </example>
      <noindent/>
      <para>
        Running
Default handler: &latex;
         on
        <file>
          constitution.tex
        </file>
         makes the material from the three files appear in the document but also generates the auxiliary files
        <file>
          preamble.aux
        </file>
        ,
        <file>
          articles.aux
        </file>
        , and
        <file>
          amendments.aux
        </file>
        . These contain information such as page numbers and cross-references (
        <pxref label="Cross-references">
          <xrefnodename>
            Cross references
          </xrefnodename>
        </pxref>
        ). If you now comment out
        <code>
          \includeonly
        </code>
Default handler: &textrsquo;
        s lines with
        <code>
          preamble
        </code>
         and
        <code>
          amendments
        </code>
         and run
Default handler: &latex;
         again then the resulting document shows only the material from
        <file>
          articles.tex
        </file>
        , not the material from
        <file>
          preamble.tex
        </file>
         or
        <file>
          amendments.tex
        </file>
        . Nonetheless, all of the auxiliary information from the omitted files is still there, including the starting page number of the chapter.
      </para>
      <para>
        If the document preamble does not have
        <code>
          \includeonly
        </code>
         then
Default handler: &latex;
         will include all the files you call for with
        <code>
          \include
        </code>
         commands.
      </para>
      <para>
        The
        <code>
          \include
        </code>
         command makes a new page. To avoid that, see
        <ref label="_005cinput">
          <xrefnodename>
            \input
          </xrefnodename>
        </ref>
         (which, however, does not retain the auxiliary information).
      </para>
      <para>
        <xref label="Larger-book-template">
          <xrefnodename>
            Larger book template
          </xrefnodename>
        </xref>
        , for another example using
        <code>
          \include
        </code>
         and
        <code>
          \includeonly
        </code>
        . That example also uses
        <code>
          \input
        </code>
         for some material that will not necessarily start on a new page.
      </para>
      <para>
        File names can involve paths.
      </para>
      <example endspaces=" ">
        <pre xml:space="preserve">
          \documentclass
Default handler: &lbrace;
          book
Default handler: &rbrace;
           \includeonly
Default handler: &lbrace;
           chapters/chap1,
Default handler: &rbrace;
           \begin
Default handler: &lbrace;
          document
Default handler: &rbrace;
           \include
Default handler: &lbrace;
          chapters/chap1
Default handler: &rbrace;
           \end
Default handler: &lbrace;
          document
Default handler: &rbrace;
        </pre>
      </example>
      <para>
        To make your document portable across distributions and platforms you should avoid spaces in the file names. The tradition is to instead use dashes or underscores. Nevertheless, for the name
        <samp>
          amo amas amat
        </samp>
        , this works under
Default handler: &tex;
         Live on GNU/Linux:
      </para>
      <findex index="fn" spaces=" ">
        <indexterm index="fn" number="1168" mergedindex="cp">
          \space
        </indexterm>
      </findex>
      <example endspaces=" ">
        <pre xml:space="preserve">
          \documentclass
Default handler: &lbrace;
          book
Default handler: &rbrace;
           \includeonly
Default handler: &lbrace;
          "
          amo\space amas\space amat
          "
Default handler: &rbrace;
           \begin
Default handler: &lbrace;
          document
Default handler: &rbrace;
           \include
Default handler: &lbrace;
          "
          amo\space amas\space amat
          "
Default handler: &rbrace;
           \end
Default handler: &lbrace;
          document
Default handler: &rbrace;
        </pre>
      </example>
      <para>
        and this works under MiK
Default handler: &tex;
         on Windows:
      </para>
      <example endspaces=" ">
        <pre xml:space="preserve">
          \documentclass
Default handler: &lbrace;
          book
Default handler: &rbrace;
           \includeonly
Default handler: &lbrace;
Default handler: &lbrace;
          "
          amo amas amat
          "
Default handler: &rbrace;
Default handler: &rbrace;
           \begin
Default handler: &lbrace;
          document
Default handler: &rbrace;
           \include
Default handler: &lbrace;
Default handler: &lbrace;
          "
          amo amas amat
          "
Default handler: &rbrace;
Default handler: &rbrace;
           \end
Default handler: &lbrace;
          document
Default handler: &rbrace;
        </pre>
      </example>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="1146">
          nested
          <code>
            \include
          </code>
          , not allowed
        </indexterm>
      </cindex>
      <para>
        You cannot use
        <code>
          \include
        </code>
         inside a file that is being included or you get
        <samp>
          LaTeX Error: \include cannot be nested.
        </samp>
         The
        <code>
          \include
        </code>
         command cannot appear in the document preamble; you will get
        <samp>
          LaTeX Error: Missing \begin
Default handler: &lbrace;
          document
Default handler: &rbrace;
        </samp>
        .
      </para>
      <para>
        If a file that you
        <code>
          \include
        </code>
         does not exist, for instance if you
        <code>
          \include
Default handler: &lbrace;
          athiesm
Default handler: &rbrace;
        </code>
         but you meant
        <code>
          \include
Default handler: &lbrace;
          atheism
Default handler: &rbrace;
        </code>
        , then
Default handler: &latex;
         does not give you an error but will warn you
        <samp>
          No file athiesm.tex.
        </samp>
         (It will also create
        <file>
          athiesm.aux
        </file>
        .)
      </para>
      <para>
        If you
        <code>
          \include
        </code>
         the root file in itself then you first get
        <samp>
          LaTeX Error: Can be used only in preamble.
        </samp>
         Later runs get
        <samp>
          TeX capacity exceeded, sorry [text input levels=15]
        </samp>
        . To fix this, you must remove the inclusion
        <code>
          \include
Default handler: &lbrace;
          <var>
            root
          </var>
Default handler: &rbrace;
        </code>
         but also delete the file
        <file>
          <var>
            root
          </var>
          .aux
        </file>
         and rerun
Default handler: &latex;
        .
      </para>
    </section>
    <node name="_005cinput" spaces=" ">
      <nodename>
        \input
      </nodename>
      <nodeprev automatic="on">
        \include
        &
         \includeonly
      </nodeprev>
      <nodeup automatic="on">
        Splitting the input
      </nodeup>
    </node>
    <section spaces=" ">
      <sectiontitle>
        <code>
          \input
        </code>
      </sectiontitle>
      <findex index="fn" spaces=" ">
        <indexterm index="fn" number="1169" mergedindex="cp">
          \input
        </indexterm>
      </findex>
      <para>
        Synopsis:
      </para>
      <example endspaces=" ">
        <pre xml:space="preserve">
          \input
Default handler: &lbrace;
          <var>
            filename
          </var>
Default handler: &rbrace;
        </pre>
      </example>
      <paraDefault handler: &latex;
>
         processes the file as if its contents were inserted in the current file. For a more sophisticated inclusion mechanism see
        <ref label="_005cinclude-_0026-_005cincludeonly">
          <xrefnodename>
            \include
            &
             \includeonly
          </xrefnodename>
        </ref>
        .
      </para>
      <para>
        If
        <var>
          filename
        </var>
         does not end in
        <samp>
          .tex
        </samp>
         then
Default handler: &latex;
         first tries the filename with that extension; this is the usual case. If
        <var>
          filename
        </var>
         ends with
        <samp>
          .tex
        </samp>
         then
Default handler: &latex;
         looks for the filename as it is.
      </para>
      <para>
        For example, this
      </para>
      <example endspaces=" ">
        <pre xml:space="preserve">
          \input
Default handler: &lbrace;
          macros
Default handler: &rbrace;
        </pre>
      </example>
      <noindent/>
      <para>
        will cause
Default handler: &latex;
         to first look for
        <file>
          macros.tex
        </file>
        . If it finds that file then it processes its contents as thought they had been copy-pasted in. If there is no file of the name
        <file>
          macros.tex
        </file>
         then
Default handler: &latex;
         tries the name
        <file>
          macros
        </file>
        , without an extension. (This may vary by distribution.)
      </para>
      <para>
        To make your document portable across distributions and platforms you should avoid spaces in the file names. The tradition is to instead use dashes or underscores. Nevertheless, for the name
        <samp>
          amo amas amat
        </samp>
        , this works under
Default handler: &tex;
         Live on GNU/Linux:
      </para>
      <findex index="fn" spaces=" ">
        <indexterm index="fn" number="1170" mergedindex="cp">
          \space
        </indexterm>
      </findex>
      <example endspaces=" ">
        <pre xml:space="preserve">
          \input
Default handler: &lbrace;
          "
          amo\space amas\space amat
          "
Default handler: &rbrace;
        </pre>
      </example>
      <para>
        and this works under MiK
Default handler: &tex;
         on Windows:
      </para>
      <example endspaces=" ">
        <pre xml:space="preserve">
          \input
Default handler: &lbrace;
Default handler: &lbrace;
          "
          amo amas amat
          "
Default handler: &rbrace;
Default handler: &rbrace;
        </pre>
      </example>
    </section>
  </chapter>
  <node name="Front_002fback-matter" spaces=" ">
    <nodename>
      Front/back matter
    </nodename>
    <nodenext automatic="on">
      Letters
    </nodenext>
    <nodeprev automatic="on">
      Splitting the input
    </nodeprev>
    <nodeup automatic="on">
      Top
    </nodeup>
  </node>
  <chapter spaces=" ">
    <sectiontitle>
      Front/back matter
    </sectiontitle>
    <menu endspaces=" ">
      <menuentry>
        <menuleadingtext>
          *
        </menuleadingtext>
        <menunode>
          Table of contents etc.
        </menunode>
        <menuseparator>
          ::
        </menuseparator>
        <menudescription>
          <pre xml:space="preserve">
            Table of contents, list of figures, list of tables.
          </pre>
        </menudescription>
      </menuentry>
      <menuentry>
        <menuleadingtext>
          *
        </menuleadingtext>
        <menunode>
          Indexes
        </menunode>
        <menuseparator>
          ::
        </menuseparator>
        <menudescription>
          <pre xml:space="preserve">
            Generate an index.
          </pre>
        </menudescription>
      </menuentry>
      <menuentry>
        <menuleadingtext>
          *
        </menuleadingtext>
        <menunode>
          Glossaries
        </menunode>
        <menuseparator>
          ::
        </menuseparator>
        <menudescription>
          <pre xml:space="preserve">
            Generate a glossary.
          </pre>
        </menudescription>
      </menuentry>
    </menu>
Default handler: <!-- c no comma in the node name because Texinfo doesn't support that well. -->
    <node name="Table-of-contents-etc_002e" spaces=" ">
      <nodename>
        Table of contents etc.
      </nodename>
      <nodenext automatic="on">
        Indexes
      </nodenext>
      <nodeup automatic="on">
        Front/back matter
      </nodeup>
    </node>
    <section spaces=" ">
      <sectiontitle>
        Table of contents, list of figures, list of tables
      </sectiontitle>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="1147">
          table of contents, creating
        </indexterm>
      </cindex>
      <findex index="fn" spaces=" ">
        <indexterm index="fn" number="1171" mergedindex="cp">
          \tableofcontents
        </indexterm>
      </findex>
      <findex index="fn" spaces=" ">
        <indexterm index="fn" number="1172" mergedindex="cp">
          .toc
          <r>
            file
          </r>
        </indexterm>
      </findex>
      <findex index="fn" spaces=" ">
        <indexterm index="fn" number="1173" mergedindex="cp">
          \listoffigures
        </indexterm>
      </findex>
      <findex index="fn" spaces=" ">
        <indexterm index="fn" number="1174" mergedindex="cp">
          \listoftables
        </indexterm>
      </findex>
      <findex index="fn" spaces=" ">
        <indexterm index="fn" number="1175" mergedindex="cp">
          .lof
          <r>
            file
          </r>
        </indexterm>
      </findex>
      <findex index="fn" spaces=" ">
        <indexterm index="fn" number="1176" mergedindex="cp">
          .lot
          <r>
            file
          </r>
        </indexterm>
      </findex>
      <para>
        Synopsis, one of:
      </para>
      <example endspaces=" ">
        <pre xml:space="preserve">
          \tableofcontents \listoffigures \listoftables
        </pre>
      </example>
      <para>
        Produce a table of contents, or list of figures, or list of tables. Put the command in the input file where you want the table or list to go. You do not type the entries; for example, typically the table of contents entries are automatically generated from the sectioning commands
        <code>
          \chapter
        </code>
        , etc.
      </para>
      <para>
        This example illustrates the first command,
        <code>
          \tableofcontents
        </code>
        .
Default handler: &latex;
         will produce a table of contents on the book
Default handler: &textrsquo;
        s first page.
      </para>
      <example endspaces=" ">
        <pre xml:space="preserve">
          \documentclass
Default handler: &lbrace;
          book
Default handler: &rbrace;
           % \setcounter
Default handler: &lbrace;
          tocdepth
Default handler: &rbrace;
Default handler: &lbrace;
          1
Default handler: &rbrace;
           \begin
Default handler: &lbrace;
          document
Default handler: &rbrace;
           \tableofcontents\newpage ... \chapter
Default handler: &lbrace;
          ...
Default handler: &rbrace;
           ... \section
Default handler: &lbrace;
          ...
Default handler: &rbrace;
           ... \subsection
Default handler: &lbrace;
          ...
Default handler: &rbrace;
           ... \end
Default handler: &lbrace;
          document
Default handler: &rbrace;
        </pre>
      </example>
      <noindent/>
      <para>
        Uncommenting the second line would cause that table to contain chapter and section listings but not subsection listings, because the
        <code>
          \section
        </code>
         command has level
Default handler: &nbsp;
        1.
        <xref label="Sectioning">
          <xrefnodename>
            Sectioning
          </xrefnodename>
        </xref>
        , for level numbers of the sectioning units. For more on the
        <code>
          tocdepth
        </code>
        <pxref label="Sectioning_002ftocdepth">
          <xrefnodename>
            Sectioning/tocdepth
          </xrefnodename>
        </pxref>
        .
      </para>
      <para>
        Another example of the use of
        <code>
          \tableofcontents
        </code>
         is in
        <ref label="Larger-book-template">
          <xrefnodename>
            Larger book template
          </xrefnodename>
        </ref>
        .
      </para>
      <para>
        If you want a page break after the table of contents, write a
        <code>
          \newpage
        </code>
         command after the
        <code>
          \tableofcontents
        </code>
         command, as above.
      </para>
      <para>
        To make the table of contents,
Default handler: &latex;
         stores the information in an auxiliary file named
        <file>
          <var>
            root-file
          </var>
          .toc
        </file>
         (
        <pxref label="Splitting-the-input">
          <xrefnodename>
            Splitting the input
          </xrefnodename>
        </pxref>
        ). For example, this
Default handler: &latex;
         file
        <file>
          test.tex
        </file>
      </para>
      <example endspaces=" ">
        <pre xml:space="preserve">
          \documentclass
Default handler: &lbrace;
          article
Default handler: &rbrace;
           \begin
Default handler: &lbrace;
          document
Default handler: &rbrace;
           \tableofcontents\newpage \section
Default handler: &lbrace;
          First section
Default handler: &rbrace;
           \subsection
Default handler: &lbrace;
          First subsection
Default handler: &rbrace;
           ...
        </pre>
      </example>
      <noindent/>
      <para>
        writes these lines to
        <file>
          test.toc
        </file>
        .
      </para>
      <example endspaces=" ">
        <pre xml:space="preserve">
          \contentsline
Default handler: &lbrace;
          section
Default handler: &rbrace;
Default handler: &lbrace;
          \numberline
Default handler: &lbrace;
          1
Default handler: &rbrace;
          First section
Default handler: &rbrace;
Default handler: &lbrace;
          2
Default handler: &rbrace;
           \contentsline
Default handler: &lbrace;
          subsection
Default handler: &rbrace;
Default handler: &lbrace;
          \numberline
Default handler: &lbrace;
          1.1
Default handler: &rbrace;
          First subsection
Default handler: &rbrace;
Default handler: &lbrace;
          2
Default handler: &rbrace;
        </pre>
      </example>
      <findex index="fn" spaces=" ">
        <indexterm index="fn" number="1177" mergedindex="cp">
          \contentsline
        </indexterm>
      </findex>
      <noindent/>
      <para>
        Each line contains a single command,
        <code>
          \contentsline
        </code>
         (
        <pxref label="_005ccontentsline">
          <xrefnodename>
            \contentsline
          </xrefnodename>
        </pxref>
        ). The first argument, the
        <code>
          section
        </code>
         or
        <code>
          subsection
        </code>
        , is the sectioning unit. The second argument has two components. The hook
        <code>
          \numberline
        </code>
         determines how the sectioning number,
        <code>
          1
        </code>
         or
        <code>
          1.1
        </code>
        , appears in the table of contents (
        <pxref label="_005cnumberline">
          <xrefnodename>
            \numberline
          </xrefnodename>
        </pxref>
        ). The remainder of the second argument of
        <code>
          \contentsline
        </code>
        ,
        <samp>
          First section
        </samp>
         or
        <samp>
          First subsection
        </samp>
        , is the sectioning title text. Finally, the third argument,
        <samp>
          2
        </samp>
        , is the page number on which this sectioning unit starts.
      </para>
      <para>
        To typeset these lines, the document class provides
        <code>
          \l
Default handler: &arobase;
          <var>
            section-unit
          </var>
        </code>
         commands such as
        <code>
          \l
Default handler: &arobase;
          section
Default handler: &lbrace;
          <var>
            text
          </var>
Default handler: &rbrace;
Default handler: &lbrace;
          <var>
            pagenumber
          </var>
Default handler: &rbrace;
        </code>
         and
        <code>
          \l
Default handler: &arobase;
          subsection
Default handler: &lbrace;
          <var>
            text
          </var>
Default handler: &rbrace;
Default handler: &lbrace;
          <var>
            pagenumber
          </var>
Default handler: &rbrace;
        </code>
        . These commands often use the
        <code>
          \
Default handler: &arobase;
          dottedtocline
        </code>
         command (
        <pxref label="_005c_0040dottedtocline">
          <xrefnodename>
            \
Default handler: &arobase;
            dottedtocline
          </xrefnodename>
        </pxref>
        ).
      </para>
      <para>
        A consequence of
Default handler: &latex;
Default handler: &textrsquo;
        s strategy of using auxiliary files is that to get the correct information in the document you must run
Default handler: &latex;
         twice, once to store the information and the second time to retrieve it. In the ordinary course of writing a document authors run
Default handler: &latex;
         a number of times, but you may notice that the first time that you compile a new document, the table of contents page will be empty except for its
        <samp>
          Contents
        </samp>
         header. Just run
Default handler: &latex;
         again.
      </para>
      <para>
        The commands
        <code>
          \listoffigures
        </code>
         and
        <code>
          \listoftables
        </code>
         produce a list of figures and a list of tables. Their information is stored in files with extension
        <file>
          .lof
        </file>
         and
        <file>
          .lot
        </file>
        . They work the same way as
        <code>
          \tableofcontents
        </code>
         but the latter is more common, so we use it for most examples.
      </para>
      <para>
        You can manually add material to the table of contents, the list of figures, and the list of tables. For instance, add a line about a section to the table of contents with
        <code>
          \addcontentsline
Default handler: &lbrace;
          toc
Default handler: &rbrace;
Default handler: &lbrace;
          section
Default handler: &rbrace;
Default handler: &lbrace;
          <var>
            text
          </var>
Default handler: &rbrace;
        </code>
        . (
        <pxref label="_005caddcontentsline">
          <xrefnodename>
            \addcontentsline
          </xrefnodename>
        </pxref>
        ). Add arbitrary material, that is, non-line material, with
        <code>
          \addtocontents
        </code>
        , as with the command
        <code>
          \addtocontents
Default handler: &lbrace;
          lof
Default handler: &rbrace;
Default handler: &lbrace;
          \protect\vspace
Default handler: &lbrace;
          2ex
Default handler: &rbrace;
Default handler: &rbrace;
        </code>
        , which adds vertical space to the list of figures (
        <pxref label="_005caddtocontents">
          <xrefnodename>
            \addtocontents
          </xrefnodename>
        </pxref>
        ).
      </para>
      <para>
        Lines in the table of contents, the list of figures, and the list of tables, have four parts. First is an indent. Next is a box into which sectioning numbers are placed, and then the third box holds the title text, such as
        <samp>
          First section
        </samp>
        . Finally there is a box up against the right margin, inside of which
Default handler: &latex;
         puts the page number box. For the indent and the width of the number box,
        <pxref label="_005c_0040dottedtocline">
          <xrefnodename>
            \
Default handler: &arobase;
            dottedtocline
          </xrefnodename>
        </pxref>
        . The right margin box has width
        <code>
          \
Default handler: &arobase;
          tocrmarg
        </code>
         and the page number is flush right in that space, inside a box of width
        <code>
          \
Default handler: &arobase;
          pnumwidth
        </code>
        . By default
        <code>
          \
Default handler: &arobase;
          tocrmarg
        </code>
         is
        <code>
          2.55em
        </code>
         and
        <code>
          \
Default handler: &arobase;
          pnumwidth
        </code>
         is
        <code>
          1.55em
        </code>
        . Change these as with
        <code>
          \renewcommand
Default handler: &lbrace;
          \
Default handler: &arobase;
          tocrmarg
Default handler: &rbrace;
Default handler: &lbrace;
          3.5em
Default handler: &rbrace;
        </code>
        .
      </para>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="1148">
          <r>
            package
          </r>
          ,
          <code>
            tocloft
          </code>
        </indexterm>
      </cindex>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="1149">
          <code>
            tocloft
          </code>
          <r>
            package
          </r>
        </indexterm>
      </cindex>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="1150">
          <r>
            package
          </r>
          ,
          <code>
            tocbibbind
          </code>
        </indexterm>
      </cindex>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="1151">
          <code>
            tocbibbind
          </code>
          <r>
            package
          </r>
        </indexterm>
      </cindex>
      <para>
        CTAN has many packages for the table of contents and lists of figures and tables (
        <pxref label="CTAN">
          <xrefnodename>
            CTAN
          </xrefnodename>
        </pxref>
        ). The package
        <code>
          tocloft
        </code>
         is convenient for adjusting some aspects of the default such as spacing. And,
        <code>
          tocbibbind
        </code>
         will automatically add the bibliography, index, etc. to the table of contents.
      </para>
      <para>
        To change the header for the table of contents page, do something like these commands before you call
        <code>
          \tableofcontents
        </code>
        , etc.
      </para>
      <example endspaces=" ">
        <pre xml:space="preserve">
          \renewcommand
Default handler: &lbrace;
          \contentsname
Default handler: &rbrace;
Default handler: &lbrace;
          Table of Contents
Default handler: &rbrace;
           \renewcommand
Default handler: &lbrace;
          \listfigurename
Default handler: &rbrace;
Default handler: &lbrace;
          Plots
Default handler: &rbrace;
           \renewcommand
Default handler: &lbrace;
          \listtablename
Default handler: &rbrace;
Default handler: &lbrace;
          Specifications
Default handler: &rbrace;
        </pre>
      </example>
      <noindent/>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="1152">
          <r>
            package
          </r>
          ,
          <code>
            babel
          </code>
        </indexterm>
      </cindex>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="1153">
          <code>
            babel
          </code>
          <r>
            package
          </r>
        </indexterm>
      </cindex>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="1154">
          <r>
            package
          </r>
          ,
          <code>
            polyglossia
          </code>
        </indexterm>
      </cindex>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="1155">
          <code>
            polyglossia
          </code>
          <r>
            package
          </r>
        </indexterm>
      </cindex>
      <para>
        Internationalization packages such as
        <code>
          babel
        </code>
         or
        <code>
          polyglossia
        </code>
         will change these headers depending on the chosen base language.
      </para>
      <menu endspaces=" ">
        <menuentry>
          <menuleadingtext>
            *
          </menuleadingtext>
          <menunode>
            \
Default handler: &arobase;
            dottedtocline
          </menunode>
          <menuseparator>
            ::
          </menuseparator>
          <menudescription>
            <pre xml:space="preserve">
              Format entry line in table of contents, etc.
            </pre>
          </menudescription>
        </menuentry>
        <menuentry>
          <menuleadingtext>
            *
          </menuleadingtext>
          <menunode>
            \addcontentsline
          </menunode>
          <menuseparator>
            ::
          </menuseparator>
          <menudescription>
            <pre xml:space="preserve">
              Add an entry to table of contents, etc.
            </pre>
          </menudescription>
        </menuentry>
        <menuentry>
          <menuleadingtext>
            *
          </menuleadingtext>
          <menunode>
            \addtocontents
          </menunode>
          <menuseparator>
            ::
          </menuseparator>
          <menudescription>
            <pre xml:space="preserve">
              Add text directly to table of contents file, etc.
            </pre>
          </menudescription>
        </menuentry>
        <menuentry>
          <menuleadingtext>
            *
          </menuleadingtext>
          <menunode>
            \contentsline
          </menunode>
          <menuseparator>
            ::
          </menuseparator>
          <menudescription>
            <pre xml:space="preserve">
              Set line in table of contents, etc.
            </pre>
          </menudescription>
        </menuentry>
        <menuentry>
          <menuleadingtext>
            *
          </menuleadingtext>
          <menunode>
            \nofiles
          </menunode>
          <menuseparator>
            ::
          </menuseparator>
          <menudescription>
            <pre xml:space="preserve">
              Prevent writing to auxiliary files.
            </pre>
          </menudescription>
        </menuentry>
        <menuentry>
          <menuleadingtext>
            *
          </menuleadingtext>
          <menunode>
            \numberline
          </menunode>
          <menuseparator>
            ::
          </menuseparator>
          <menudescription>
            <pre xml:space="preserve">
              Put its number argument flush left in a box.
            </pre>
          </menudescription>
        </menuentry>
      </menu>
      <node name="_005c_0040dottedtocline" spaces=" ">
        <nodename>
          \
Default handler: &arobase;
          dottedtocline
        </nodename>
        <nodenext automatic="on">
          \addcontentsline
        </nodenext>
        <nodeup automatic="on">
          Table of contents etc.
        </nodeup>
      </node>
      <subsection spaces=" ">
        <sectiontitle>
          <code>
            \
Default handler: &arobase;
            dottedtocline
          </code>
        </sectiontitle>
        <findex index="fn" spaces=" ">
          <indexterm index="fn" number="1178" mergedindex="cp">
            \
Default handler: &arobase;
            dottedtocline
          </indexterm>
        </findex>
        <cindex index="cp" spaces=" ">
          <indexterm index="cp" number="1156">
            table of contents entry, create dotted line
          </indexterm>
        </cindex>
        <para>
          Synopsis:
        </para>
        <example endspaces=" ">
          <pre xml:space="preserve">
            \
Default handler: &arobase;
            dottedtocline
Default handler: &lbrace;
            <var>
              section-level-num
            </var>
Default handler: &rbrace;
Default handler: &lbrace;
            <var>
              indent
            </var>
Default handler: &rbrace;
Default handler: &lbrace;
            <var>
              numwidth
            </var>
Default handler: &rbrace;
Default handler: &lbrace;
            <var>
              text
            </var>
Default handler: &rbrace;
Default handler: &lbrace;
            <var>
              pagenumber
            </var>
Default handler: &rbrace;
          </pre>
        </example>
        <para>
          Used internally by
Default handler: &latex;
           to format an entry line in the table of contents, list of figures, or list of tables. Authors do not directly enter
          <code>
            \
Default handler: &arobase;
            dottedtocline
          </code>
           commands.
        </para>
        <para>
          This command is typically used by
          <code>
            \l
Default handler: &arobase;
            section
          </code>
          ,
          <code>
            \l
Default handler: &arobase;
            subsection
          </code>
          , etc., to format the content lines. For example, the
          <file>
            article.cls
          </file>
           file contains these definitions:
        </para>
        <example endspaces=" ">
          <pre xml:space="preserve">
            \newcommand*\l
Default handler: &arobase;
            section
Default handler: &lbrace;
            \
Default handler: &arobase;
            dottedtocline
Default handler: &lbrace;
            1
Default handler: &rbrace;
Default handler: &lbrace;
            1.5em
Default handler: &rbrace;
Default handler: &lbrace;
            2.3em
Default handler: &rbrace;
Default handler: &rbrace;
             \newcommand*\l
Default handler: &arobase;
            subsection
Default handler: &lbrace;
            \
Default handler: &arobase;
            dottedtocline
Default handler: &lbrace;
            2
Default handler: &rbrace;
Default handler: &lbrace;
            3.8em
Default handler: &rbrace;
Default handler: &lbrace;
            3.2em
Default handler: &rbrace;
Default handler: &rbrace;
             \newcommand*\l
Default handler: &arobase;
            subsubsection
Default handler: &lbrace;
            \
Default handler: &arobase;
            dottedtocline
Default handler: &lbrace;
            3
Default handler: &rbrace;
Default handler: &lbrace;
            7.0em
Default handler: &rbrace;
Default handler: &lbrace;
            4.1em
Default handler: &rbrace;
Default handler: &rbrace;
          </pre>
        </example>
        <noindent/>
        <para>
          In this example,
          <code>
            \
Default handler: &arobase;
            dottedcline
          </code>
           appears to have been given only three arguments. But tracing the internal code shows that it picks up the final
          <var>
            text
          </var>
           and
          <var>
            pagenumber
          </var>
           arguments in the synopsis from a call to
          <code>
            \contentsline
          </code>
           (
          <pxref label="_005ccontentsline">
            <xrefnodename>
              \contentsline
            </xrefnodename>
          </pxref>
          ).
        </para>
        <cindex index="cp" spaces=" ">
          <indexterm index="cp" number="1157">
            leaders, dots in table of contents
          </indexterm>
        </cindex>
        <para>
          Between the box for the title text of a section and the right margin box, these
          <code>
            \
Default handler: &arobase;
            dottedtocline
          </code>
           commands insert
          <dfn>
            leaders
          </dfn>
          , that is, evenly-spaced dots. The dot-to-dot space is given by the command
          <code>
            \
Default handler: &arobase;
            dotsep
          </code>
          . By default it is 4.5 (it is in math units, aka.
Default handler: &noeos;
          <code>
            mu
          </code>
          , which are
          <code>
            1/18
          </code>
Default handler: &nbsp;
          em. Change it using
          <code>
            \renewcommand
          </code>
          , as in
          <code>
            \renewcommand
Default handler: &lbrace;
            \
Default handler: &arobase;
            dotsep
Default handler: &rbrace;
Default handler: &lbrace;
            3.5
Default handler: &rbrace;
          </code>
          .
        </para>
        <para>
          In the standard
          <file>
            book
          </file>
           class,
Default handler: &latex;
           does not use dotted leaders for the Part and Chapter table entries, and in the standard
          <file>
            article
          </file>
           class it does not use dotted leaders for Section entries.
        </para>
      </subsection>
      <node name="_005caddcontentsline" spaces=" ">
        <nodename>
          \addcontentsline
        </nodename>
        <nodenext automatic="on">
          \addtocontents
        </nodenext>
        <nodeprev automatic="on">
          \
Default handler: &arobase;
          dottedtocline
        </nodeprev>
        <nodeup automatic="on">
          Table of contents etc.
        </nodeup>
      </node>
      <subsection spaces=" ">
        <sectiontitle>
          <code>
            \addcontentsline
          </code>
        </sectiontitle>
        <findex index="fn" spaces=" ">
          <indexterm index="fn" number="1179" mergedindex="cp">
            \addcontentsline
          </indexterm>
        </findex>
        <cindex index="cp" spaces=" ">
          <indexterm index="cp" number="1158">
            table of contents entry, manually adding
          </indexterm>
        </cindex>
        <para>
          Synopsis:
        </para>
        <example endspaces=" ">
          <pre xml:space="preserve">
            \addcontentsline
Default handler: &lbrace;
            <var>
              ext
            </var>
Default handler: &rbrace;
Default handler: &lbrace;
            <var>
              unit
            </var>
Default handler: &rbrace;
Default handler: &lbrace;
            <var>
              text
            </var>
Default handler: &rbrace;
          </pre>
        </example>
        <findex index="fn" spaces=" ">
          <indexterm index="fn" number="1180" mergedindex="cp">
            \contentsline
          </indexterm>
        </findex>
        <para>
          Add an entry to the auxiliary file with extension
          <var>
            ext
          </var>
          .
        </para>
        <para>
          The following will result in an
          <samp>
            Appendices
          </samp>
           line in the table of contents.
        </para>
        <example endspaces=" ">
          <pre xml:space="preserve">
            \addcontentsline
Default handler: &lbrace;
            toc
Default handler: &rbrace;
Default handler: &lbrace;
            section
Default handler: &rbrace;
Default handler: &lbrace;
            \protect\textbf
Default handler: &lbrace;
            Appendices
Default handler: &rbrace;
Default handler: &rbrace;
          </pre>
        </example>
        <noindent/>
        <para>
          It will appear at the same indentation level as the sections, will be in boldface, and will be assigned the page number associated with the point where the command appears in the input file.
        </para>
        <para>
          The
          <code>
            \addcontentsline
          </code>
           command writes information to the file
          <file>
            <var>
              root-name
            </var>
            .
            <var>
              ext
            </var>
          </file>
          , where
          <var>
            root-name
          </var>
           is the file name of the root file (
          <pxref label="Splitting-the-input">
            <xrefnodename>
              Splitting the input
            </xrefnodename>
          </pxref>
          ). It writes that information as the text of the command
          <code>
            \contentsline
Default handler: &lbrace;
            <var>
              unit
            </var>
Default handler: &rbrace;
Default handler: &lbrace;
            <var>
              text
            </var>
Default handler: &rbrace;
Default handler: &lbrace;
            <var>
              num
            </var>
Default handler: &rbrace;
          </code>
          , where
          <code>
            <var>
              num
            </var>
          </code>
           is the current value of counter
          <code>
            <var>
              unit
            </var>
          </code>
           (
          <pxref label="_005ccontentsline">
            <xrefnodename>
              \contentsline
            </xrefnodename>
          </pxref>
          ). The most common case is the table of contents and there
          <var>
            num
          </var>
           is the page number of the first page of
          <var>
            unit
          </var>
          .
        </para>
        <para>
          This command is invoked by the sectioning commands
          <code>
            \chapter
          </code>
          , etc. (
          <pxref label="Sectioning">
            <xrefnodename>
              Sectioning
            </xrefnodename>
          </pxref>
          ), and also by
          <code>
            \caption
          </code>
           inside a float environment (
          <pxref label="Floats">
            <xrefnodename>
              Floats
            </xrefnodename>
          </pxref>
          ). But it is also directly used by authors. For example, an author writing a book whose style is to have an unnumbered preface may use the starred
          <code>
            \chapter*
          </code>
          . But that command leaves out table of contents information, which can be entered manually, as here.
        </para>
        <example endspaces=" ">
          <pre xml:space="preserve">
            \chapter*
Default handler: &lbrace;
            Preface
Default handler: &rbrace;
             \addcontentsline
Default handler: &lbrace;
            toc
Default handler: &rbrace;
Default handler: &lbrace;
            chapter
Default handler: &rbrace;
Default handler: &lbrace;
            \protect\numberline
Default handler: &lbrace;
Default handler: &rbrace;
            Preface
Default handler: &rbrace;
          </pre>
        </example>
        <noindent/>
        <para>
          In the
          <file>
            <var>
              root-name
            </var>
            .toc
          </file>
           file
Default handler: &latex;
           will put the line
          <code>
            \contentsline
Default handler: &lbrace;
            chapter
Default handler: &rbrace;
Default handler: &lbrace;
            \numberline
Default handler: &lbrace;
Default handler: &rbrace;
            Preface
Default handler: &rbrace;
Default handler: &lbrace;
            3
Default handler: &rbrace;
          </code>
          ; note that the page number
          <samp>
            3
          </samp>
           is automatically generated by the system, not entered manually.
        </para>
        <para>
          All of the arguments for
          <code>
            \addcontentsline
          </code>
           are required.
        </para>
        <table commandarg="var" spaces=" " endspaces=" ">
          <tableentry>
            <tableterm>
              <item spaces=" ">
                <itemformat command="var">
                  ext
                </itemformat>
              </item>
            </tableterm>
            <tableitem>
              <para>
                Typically one of the strings
                <code>
                  toc
                </code>
                 for the table of contents,
                <code>
                  lof
                </code>
                 for the list of figures, or
                <code>
                  lot
                </code>
                 for the list of tables. The filename extension of the information file.
              </para>
            </tableitem>
          </tableentry>
          <tableentry>
            <tableterm>
              <item spaces=" ">
                <itemformat command="var">
                  unit
                </itemformat>
              </item>
            </tableterm>
            <tableitem>
              <para>
                A string that depends on the value of the
                <var>
                  ext
                </var>
                 argument, typically one of:
              </para>
              <table commandarg="code" spaces=" " endspaces=" ">
                <tableentry>
                  <tableterm>
                    <item spaces=" ">
                      <itemformat command="code">
                        toc
                      </itemformat>
                    </item>
                  </tableterm>
                  <tableitem>
                    <para>
                      For the table of contents, this is the name of a sectional unit:
                      <code>
                        part
                      </code>
                      ,
                      <code>
                        chapter
                      </code>
                      ,
                      <code>
                        section
                      </code>
                      ,
                      <code>
                        subsection
                      </code>
                      , etc.
                    </para>
                  </tableitem>
                </tableentry>
                <tableentry>
                  <tableterm>
                    <item spaces=" ">
                      <itemformat command="code">
                        lof
                      </itemformat>
                    </item>
                  </tableterm>
                  <tableitem>
                    <para>
                      For the list of figures:
                      <code>
                        figure
                      </code>
                      .
                    </para>
                  </tableitem>
                </tableentry>
                <tableentry>
                  <tableterm>
                    <item spaces=" ">
                      <itemformat command="code">
                        lot
                      </itemformat>
                    </item>
                  </tableterm>
                  <tableitem>
                    <para>
                      For the list of tables:
                      <code>
                        table
                      </code>
                      .
                    </para>
                  </tableitem>
                </tableentry>
              </table>
            </tableitem>
          </tableentry>
          <tableentry>
            <tableterm>
              <item spaces=" ">
                <itemformat command="var">
                  text
                </itemformat>
              </item>
            </tableterm>
            <tableitem>
              <para>
                The text of the entry. You must
                <code>
                  \protect
                </code>
                 any fragile commands (
                <pxref label="_005cprotect">
                  <xrefnodename>
                    \protect
                  </xrefnodename>
                </pxref>
                ) used in it.
              </para>
            </tableitem>
          </tableentry>
        </table>
        <para>
          The
          <code>
            \addcontentsline
          </code>
           command has an interaction with
          <code>
            \include
          </code>
           (
          <pxref label="_005cinclude-_0026-_005cincludeonly">
            <xrefnodename>
              \include
              &
               \includeonly
            </xrefnodename>
          </pxref>
          ). If you use them at the same level, as with
          <code>
            \addcontentsline
Default handler: &lbrace;
            ...
Default handler: &rbrace;
Default handler: &lbrace;
            ...
Default handler: &rbrace;
Default handler: &lbrace;
            ...
Default handler: &rbrace;
            \include
Default handler: &lbrace;
            ...
Default handler: &rbrace;
          </code>
           then lines in the table of contents can come out in the wrong order. The solution is to move
          <code>
            \addcontentsline
          </code>
           into the file being included.
        </para>
        <para>
          If you use a
          <var>
            unit
          </var>
           that
Default handler: &latex;
           does not recognize, as with the typo here
        </para>
        <example endspaces=" ">
          <pre xml:space="preserve">
            \addcontentsline
Default handler: &lbrace;
            toc
Default handler: &rbrace;
Default handler: &lbrace;
            setcion
Default handler: &rbrace;
Default handler: &lbrace;
            \protect\textbf
Default handler: &lbrace;
            Appendices
Default handler: &rbrace;
Default handler: &rbrace;
          </pre>
        </example>
        <noindent/>
        <para>
          then you don
Default handler: &textrsquo;
          t get an error but the formatting in the table of contents will not make sense.
        </para>
      </subsection>
      <node name="_005caddtocontents" spaces=" ">
        <nodename>
          \addtocontents
        </nodename>
        <nodenext automatic="on">
          \contentsline
        </nodenext>
        <nodeprev automatic="on">
          \addcontentsline
        </nodeprev>
        <nodeup automatic="on">
          Table of contents etc.
        </nodeup>
      </node>
      <subsection spaces=" ">
        <sectiontitle>
          <code>
            \addtocontents
          </code>
        </sectiontitle>
        <findex index="fn" spaces=" ">
          <indexterm index="fn" number="1181" mergedindex="cp">
            \addtocontents
Default handler: &lbrace;
            <var>
              ext
            </var>
Default handler: &rbrace;
Default handler: &lbrace;
            <var>
              text
            </var>
Default handler: &rbrace;
          </indexterm>
        </findex>
        <para>
          Synopsis:
        </para>
        <example endspaces=" ">
          <pre xml:space="preserve">
            \addtocontents
Default handler: &lbrace;
            <var>
              ext
            </var>
Default handler: &rbrace;
Default handler: &lbrace;
            <var>
              text
            </var>
Default handler: &rbrace;
          </pre>
        </example>
        <para>
          Add
          <var>
            text
          </var>
          , which may be text or formatting commands, directly to the auxiliary file with extension
          <var>
            ext
          </var>
          . This is most commonly used for the table of contents so that is the discussion here, but it also applies to the list of figures and list of tables.
        </para>
        <para>
          This will put some vertical space in the table of contents after the
          <samp>
            Contents
          </samp>
           header.
        </para>
        <example endspaces=" ">
          <pre xml:space="preserve">
            \tableofcontents\newpage \addtocontents
Default handler: &lbrace;
            toc
Default handler: &rbrace;
Default handler: &lbrace;
            \protect\vspace*
Default handler: &lbrace;
            3ex
Default handler: &rbrace;
Default handler: &rbrace;
          </pre>
        </example>
        <noindent/>
        <para>
          This puts the word
          <samp>
            Page
          </samp>
          , in boldface, above the column of page numbers and after the header.
        </para>
        <example endspaces=" ">
          <pre xml:space="preserve">
            \tableofcontents \addtocontents
Default handler: &lbrace;
            toc
Default handler: &rbrace;
Default handler: &lbrace;
            ~\hfill\textbf
Default handler: &lbrace;
            Page
Default handler: &rbrace;
            \par
Default handler: &rbrace;
             \chapter
Default handler: &lbrace;
            ...
Default handler: &rbrace;
          </pre>
        </example>
        <noindent/>
        <para>
          This adds a line announcing work by a new author.
        </para>
        <example endspaces=" ">
          <pre xml:space="preserve">
            \addtocontents
Default handler: &lbrace;
            toc
Default handler: &rbrace;
Default handler: &lbrace;
            % \protect\vspace
Default handler: &lbrace;
            2ex
Default handler: &rbrace;
             \textbf
Default handler: &lbrace;
            Chapters by N. Other Author
Default handler: &rbrace;
            \par
Default handler: &rbrace;
          </pre>
        </example>
        <para>
          The difference between
          <code>
            \addtocontents
          </code>
           and
          <code>
            \addcontentsline
          </code>
           is that the latter is strictly for lines, such as with a line giving the page number for the start of a new subset of the chapters. As the above examples show,
          <code>
            \addtocontents
          </code>
           is for material such as spacing.
        </para>
        <para>
          The
          <code>
            \addtocontents
          </code>
           command has two arguments. Both are required.
        </para>
        <table commandarg="var" spaces=" " endspaces=" ">
          <tableentry>
            <tableterm>
              <item spaces=" ">
                <itemformat command="var">
                  ext
                </itemformat>
              </item>
            </tableterm>
            <tableitem>
              <para>
                Typically one of:
                <file>
                  toc
                </file>
                 for the table of contents,
                <file>
                  lof
                </file>
                 for the list of figures, or
                <file>
                  lot
                </file>
                 for the list of tables. The extension of the file holding the information.
              </para>
            </tableitem>
          </tableentry>
          <tableentry>
            <tableterm>
              <item spaces=" ">
                <itemformat command="var">
                  text
                </itemformat>
              </item>
            </tableterm>
            <tableitem>
              <para>
                The text, and possibly commands, to be written.
              </para>
            </tableitem>
          </tableentry>
        </table>
        <para>
          The sectioning commands such as
          <code>
            \chapter
          </code>
           use the
          <code>
            \addcontentsline
          </code>
           command to store information. This command creates lines in the
          <file>
            .toc
          </file>
           auxiliary file containing the
          <code>
            \contentsline
          </code>
           command (
          <pxref label="_005caddcontentsline">
            <xrefnodename>
              \addcontentsline
            </xrefnodename>
          </pxref>
          ). In contrast, the command
          <code>
            \addtocontents
          </code>
           puts material directly in that file.
        </para>
        <para>
          The
          <code>
            \addtocontents
          </code>
           command has an interaction with
          <code>
            \include
          </code>
           (
          <pxref label="_005cinclude-_0026-_005cincludeonly">
            <xrefnodename>
              \include
              &
               \includeonly
            </xrefnodename>
          </pxref>
          ). If you use them at the same level, as with
          <code>
            \addtocontents
Default handler: &lbrace;
            ...
Default handler: &rbrace;
Default handler: &lbrace;
            ...
Default handler: &rbrace;
            \include
Default handler: &lbrace;
            ...
Default handler: &rbrace;
          </code>
           then lines in the table of contents can come out in the wrong order. The solution is to move
          <code>
            \addtocontents
          </code>
           into the file being included.
        </para>
      </subsection>
      <node name="_005ccontentsline" spaces=" ">
        <nodename>
          \contentsline
        </nodename>
        <nodenext automatic="on">
          \nofiles
        </nodenext>
        <nodeprev automatic="on">
          \addtocontents
        </nodeprev>
        <nodeup automatic="on">
          Table of contents etc.
        </nodeup>
      </node>
      <subsection spaces=" ">
        <sectiontitle>
          <code>
            \contentsline
          </code>
        </sectiontitle>
        <cindex index="cp" spaces=" ">
          <indexterm index="cp" number="1159">
            table of contents
          </indexterm>
        </cindex>
        <findex index="fn" spaces=" ">
          <indexterm index="fn" number="1182" mergedindex="cp">
            \contentsline
          </indexterm>
        </findex>
        <findex index="fn" spaces=" ">
          <indexterm index="fn" number="1183" mergedindex="cp">
            \tableofcontents
          </indexterm>
        </findex>
        <findex index="fn" spaces=" ">
          <indexterm index="fn" number="1184" mergedindex="cp">
            .toc
            <r>
              file
            </r>
          </indexterm>
        </findex>
        <findex index="fn" spaces=" ">
          <indexterm index="fn" number="1185" mergedindex="cp">
            \listoffigures
          </indexterm>
        </findex>
        <findex index="fn" spaces=" ">
          <indexterm index="fn" number="1186" mergedindex="cp">
            \listoftables
          </indexterm>
        </findex>
        <findex index="fn" spaces=" ">
          <indexterm index="fn" number="1187" mergedindex="cp">
            .lof
            <r>
              file
            </r>
          </indexterm>
        </findex>
        <findex index="fn" spaces=" ">
          <indexterm index="fn" number="1188" mergedindex="cp">
            .lot
            <r>
              file
            </r>
          </indexterm>
        </findex>
        <findex index="fn" spaces=" ">
          <indexterm index="fn" number="1189" mergedindex="cp">
            \l
Default handler: &arobase;
            chapter
          </indexterm>
        </findex>
        <findex index="fn" spaces=" ">
          <indexterm index="fn" number="1190" mergedindex="cp">
            \l
Default handler: &arobase;
            section
          </indexterm>
        </findex>
        <findex index="fn" spaces=" ">
          <indexterm index="fn" number="1191" mergedindex="cp">
            \l
Default handler: &arobase;
            subsection
          </indexterm>
        </findex>
        <para>
          Synopsis:
        </para>
        <example endspaces=" ">
          <pre xml:space="preserve">
            \contentsline
Default handler: &lbrace;
            <var>
              unit
            </var>
Default handler: &rbrace;
Default handler: &lbrace;
            <var>
              text
            </var>
Default handler: &rbrace;
Default handler: &lbrace;
            <var>
              pagenumber
            </var>
Default handler: &rbrace;
          </pre>
        </example>
        <para>
          Used internally by
Default handler: &latex;
           to typeset an entry of the table of contents, list of figures, or list of tables (
          <pxref label="Table-of-contents-etc_002e">
            <xrefnodename>
              Table of contents etc.
            </xrefnodename>
          </pxref>
          ). Authors do not directly enter
          <code>
            \contentsline
          </code>
           commands.
        </para>
        <para>
          Usually adding material to these lists is done automatically by the commands
          <code>
            \chapter
          </code>
          ,
          <code>
            \section
          </code>
          , etc. for the table of contents, or by the
          <code>
            \caption
          </code>
           command inside of a
          <code>
            \figure
          </code>
           or
          <code>
            \table
          </code>
           environment (
          <pxref label="figure">
            <xrefnodename>
              figure
            </xrefnodename>
          </pxref>
           and
          <pxref label="table">
            <xrefnodename>
              table
            </xrefnodename>
          </pxref>
          ). Thus, where the root file is
          <file>
            thesis.tex
          </file>
          , and contains the declaration
          <code>
            \tableofcontents
          </code>
          , the command
          <code>
            \chapter
Default handler: &lbrace;
            Chapter One
Default handler: &rbrace;
          </code>
           produces something like this in the file
          <file>
            thesis.toc
          </file>
          .
        </para>
        <example endspaces=" ">
          <pre xml:space="preserve">
            \contentsline
Default handler: &lbrace;
            chapter
Default handler: &rbrace;
Default handler: &lbrace;
            \numberline
Default handler: &lbrace;
            1
Default handler: &rbrace;
            Chapter One
Default handler: &rbrace;
Default handler: &lbrace;
            3
Default handler: &rbrace;
          </pre>
        </example>
        <para>
          If the file contains the declaration
          <code>
            \listoffigures
          </code>
           then a figure environment involving
          <code>
            \caption
Default handler: &lbrace;
            Test
Default handler: &rbrace;
          </code>
           will produce something like this in
          <file>
            thesis.lof
          </file>
          .
        </para>
        <example endspaces=" ">
          <pre xml:space="preserve">
            \contentsline
Default handler: &lbrace;
            figure
Default handler: &rbrace;
Default handler: &lbrace;
            \numberline
Default handler: &lbrace;
            1.1
Default handler: &rbrace;
Default handler: &lbrace;
            \ignorespaces Test
Default handler: &rbrace;
Default handler: &rbrace;
Default handler: &lbrace;
            6
Default handler: &rbrace;
          </pre>
        </example>
        <para>
          To manually add material, use
          <code>
            \addcontentsline
Default handler: &lbrace;
            <var>
              filetype
            </var>
Default handler: &rbrace;
Default handler: &lbrace;
            <var>
              unit
            </var>
Default handler: &rbrace;
Default handler: &lbrace;
            <var>
              text
            </var>
Default handler: &rbrace;
          </code>
          , where
          <var>
            filetype
          </var>
           is
          <code>
            toc
          </code>
          ,
          <code>
            lof
          </code>
          , or
          <code>
            lot
          </code>
           (
          <pxref label="_005caddcontentsline">
            <xrefnodename>
              \addcontentsline
            </xrefnodename>
          </pxref>
          ).
        </para>
        <cindex index="cp" spaces=" ">
          <indexterm index="cp" number="1160">
            <r>
              package
            </r>
            ,
            <code>
              tocloft
            </code>
          </indexterm>
        </cindex>
        <cindex index="cp" spaces=" ">
          <indexterm index="cp" number="1161">
            <code>
              tocloft
            </code>
            <r>
              package
            </r>
          </indexterm>
        </cindex>
        <para>
          For manipulating how the
          <code>
            \contentline
          </code>
           material is typeset, see the
          <code>
            tocloft
          </code>
           package.
        </para>
        <cindex index="cp" spaces=" ">
          <indexterm index="cp" number="1162">
            <r>
              package
            </r>
            ,
            <code>
              hyperref
            </code>
          </indexterm>
        </cindex>
        <cindex index="cp" spaces=" ">
          <indexterm index="cp" number="1163">
            <code>
              hyperref
            </code>
            <r>
              package
            </r>
          </indexterm>
        </cindex>
        <para>
          Note that the
          <code>
            hyperref
          </code>
           package changes the definition of
          <code>
            \contentsline
          </code>
           (and
          <code>
            \addcontentsline
          </code>
          ) to add more arguments, to make hyperlinks. This is the source of the error
          <code>
            Argument of \contentsline has an extra
Default handler: &rbrace;
          </code>
           when one adds/remove the use of package
          <code>
            hyperref
          </code>
           and a compilation was already run. Fix this error by deleting the
          <file>
            .toc
          </file>
           or
          <file>
            .lof
          </file>
           or
          <file>
            .lot
          </file>
           file, and running
Default handler: &latex;
           again.
        </para>
      </subsection>
      <node name="_005cnofiles" spaces=" ">
        <nodename>
          \nofiles
        </nodename>
        <nodenext automatic="on">
          \numberline
        </nodenext>
        <nodeprev automatic="on">
          \contentsline
        </nodeprev>
        <nodeup automatic="on">
          Table of contents etc.
        </nodeup>
      </node>
      <subsection spaces=" ">
        <sectiontitle>
          <code>
            \nofiles
          </code>
        </sectiontitle>
        <findex index="fn" spaces=" ">
          <indexterm index="fn" number="1192" mergedindex="cp">
            \nofiles
          </indexterm>
        </findex>
        <para>
          Synopsis:
        </para>
        <example endspaces=" ">
          <pre xml:space="preserve">
            \nofiles
          </pre>
        </example>
        <para>
          Prevent
Default handler: &latex;
           from writing any auxiliary files. The only output will be the
          <file>
            .log
          </file>
           and
          <file>
            .pdf
          </file>
           (or
          <file>
            .dvi
          </file>
          ) files. This command must go in the preamble.
        </para>
        <para>
          Because of the
          <code>
            \nofiles
          </code>
           command this example will not produce a
          <file>
            .toc
          </file>
           file.
        </para>
        <example endspaces=" ">
          <pre xml:space="preserve">
            \documentclass
Default handler: &lbrace;
            book
Default handler: &rbrace;
             \nofiles \begin
Default handler: &lbrace;
            document
Default handler: &rbrace;
             \tableofcontents\newpage \chapter
Default handler: &lbrace;
            ...
Default handler: &rbrace;
             ...
          </pre>
        </example>
        <noindent/>
        <paraDefault handler: &latex;
>
           will not erase any existing auxiliary files, so if you insert the
          <code>
            \nofiles
          </code>
           command after you have run the file and gotten a
          <file>
            .toc
          </file>
           then the table of contents page will continue to show the old information.
        </para>
      </subsection>
      <node name="_005cnumberline" spaces=" ">
        <nodename>
          \numberline
        </nodename>
        <nodeprev automatic="on">
          \nofiles
        </nodeprev>
        <nodeup automatic="on">
          Table of contents etc.
        </nodeup>
      </node>
      <subsection spaces=" ">
        <sectiontitle>
          <code>
            \numberline
          </code>
        </sectiontitle>
        <findex index="fn" spaces=" ">
          <indexterm index="fn" number="1193" mergedindex="cp">
            \numberline
          </indexterm>
        </findex>
        <para>
          Synopsis:
        </para>
        <example endspaces=" ">
          <pre xml:space="preserve">
            \numberline
Default handler: &lbrace;
            <var>
              number
            </var>
Default handler: &rbrace;
          </pre>
        </example>
        <para>
          Typeset its argument flush left in a box. This is used in a
          <code>
            \contentsline
          </code>
           command to typeset the section number (
          <pxref label="_005ccontentsline">
            <xrefnodename>
              \contentsline
            </xrefnodename>
          </pxref>
          ).
        </para>
        <para>
          For example, this line in a
          <file>
            .toc
          </file>
           file causes the
          <code>
            1.1
          </code>
           to be typeset flush left.
        </para>
        <example endspaces=" ">
          <pre xml:space="preserve">
            \contentsline
Default handler: &lbrace;
            subsection
Default handler: &rbrace;
Default handler: &lbrace;
            \numberline
Default handler: &lbrace;
            1.1
Default handler: &rbrace;
            Motivation
Default handler: &rbrace;
Default handler: &lbrace;
            2
Default handler: &rbrace;
          </pre>
        </example>
        <para>
          By default,
Default handler: &latex;
           typesets the section numbers in a box of length
          <code>
            \
Default handler: &arobase;
            tempdima
          </code>
          . That length is set by the commands
          <code>
            \l
Default handler: &arobase;
            section
          </code>
          ,
          <code>
            \l
Default handler: &arobase;
            subsection
          </code>
          , etc. Put section numbers inside a natural-width box with
          <code>
            \renewcommand
Default handler: &lbrace;
            \numberline
Default handler: &rbrace;
            [1]
Default handler: &lbrace;
            #1~
Default handler: &rbrace;
          </code>
           before
          <code>
            \tableofcontents
          </code>
          .
        </para>
        <para>
          This command is fragile so you may need to precede it with
          <code>
            \protect
          </code>
           (
          <pxref label="_005cprotect">
            <xrefnodename>
              \protect
            </xrefnodename>
          </pxref>
          ). An example is the use of
          <code>
            \protect
          </code>
           in this command,
        </para>
        <example endspaces=" ">
          <pre xml:space="preserve">
            <code>
              \addcontentsline
Default handler: &lbrace;
              toc
Default handler: &rbrace;
Default handler: &lbrace;
              section
Default handler: &rbrace;
Default handler: &lbrace;
              \protect\numberline
Default handler: &lbrace;
Default handler: &rbrace;
              Summary
Default handler: &rbrace;
            </code>
          </pre>
        </example>
        <noindent/>
        <para>
          to get the
          <code>
            \numberline
          </code>
           into the
          <code>
            \contentsline
          </code>
           command in the
          <file>
            .toc
          </file>
           file:
          <code>
            \contentsline
Default handler: &lbrace;
            section
Default handler: &rbrace;
Default handler: &lbrace;
            \numberline
Default handler: &lbrace;
Default handler: &rbrace;
            Summary
Default handler: &rbrace;
Default handler: &lbrace;
            6
Default handler: &rbrace;
          </code>
           (the page number
          <samp>
            6
          </samp>
           is automatically added by
Default handler: &latex;
          ;
          <pxref label="_005caddcontentsline">
            <xrefnodename>
              \addcontentsline
            </xrefnodename>
          </pxref>
          ).
        </para>
      </subsection>
    </section>
    <node name="Indexes" spaces=" ">
      <nodename>
        Indexes
      </nodename>
      <nodenext automatic="on">
        Glossaries
      </nodenext>
      <nodeprev automatic="on">
        Table of contents etc.
      </nodeprev>
      <nodeup automatic="on">
        Front/back matter
      </nodeup>
    </node>
    <section spaces=" ">
      <sectiontitle>
        Indexes
      </sectiontitle>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="1164">
          indexes
        </indexterm>
      </cindex>
      <findex index="fn" spaces=" ">
        <indexterm index="fn" number="1194" mergedindex="cp">
          \makeindex
        </indexterm>
      </findex>
      <findex index="fn" spaces=" ">
        <indexterm index="fn" number="1195" mergedindex="cp">
          \index
        </indexterm>
      </findex>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="1165">
          <file>
            .idx
          </file>
           file
        </indexterm>
      </cindex>
      <para>
        If you tell
Default handler: &latex;
         what terms you want to appear in an index then it can produce that index, alphabetized and with the page numbers automatically maintained. This illustrates the basics.
      </para>
      <example endspaces=" ">
        <pre xml:space="preserve">
          \documentclass
Default handler: &lbrace;
          article
Default handler: &rbrace;
           \usepackage
Default handler: &lbrace;
          makeidx
Default handler: &rbrace;
           % Provide indexing commands \makeindex % \usepackage
Default handler: &lbrace;
          showidx
Default handler: &rbrace;
           % Show marginal notes of index entries ... \begin
Default handler: &lbrace;
          document
Default handler: &rbrace;
           ... Wilson's Theorem\index
Default handler: &lbrace;
          Wilson's Theorem
Default handler: &rbrace;
           says that a number $n
          >
          1$ is prime if and only if the factorial of $n-1$ is congruent to $-1$ modulo~$n$.\index
Default handler: &lbrace;
          congruence!and Wilson's Theorem
Default handler: &rbrace;
           ... \printindex \end
Default handler: &lbrace;
          document
Default handler: &rbrace;
        </pre>
      </example>
      <noindent/>
      <para>
        As that shows, declare index entries with the
        <code>
          \index
        </code>
         command (
        <pxref label="_005cindex">
          <xrefnodename>
            \index
          </xrefnodename>
        </pxref>
        ). When you run
Default handler: &latex;
        , the
        <code>
          \index
        </code>
         writes its information, such as
        <samp>
          Wilson's Theorem
        </samp>
         and the page number, to an auxiliary file whose name ends in
        <file>
          .idx
        </file>
        . Next, to alphabetize and do other manipulations, run an external command, typically
        <command>
          makeindex
        </command>
         (
        <pxref label="makeindex">
          <xrefnodename>
            makeindex
          </xrefnodename>
        </pxref>
        ), which writes a file whose name ends in
        <file>
          .ind
        </file>
        . Finally,
        <code>
          \printindex
        </code>
         brings this manipulated information into the output (
        <pxref label="_005cprintindex">
          <xrefnodename>
            \printindex
          </xrefnodename>
        </pxref>
        ).
      </para>
      <para>
        Thus, if the above example is in the file
        <file>
          numth.tex
        </file>
         then running
        <samp>
          pdflatex numth
        </samp>
         will save index entry and page number information to
        <file>
          numth.idx
        </file>
        . Then running
        <samp>
          makeindex numth
        </samp>
         will alphabetize and save the results to
        <file>
          numth.ind
        </file>
        . Finally, again running
        <samp>
          pdflatex numth
        </samp>
         will show the desired index, at the place where the
        <code>
          \printindex
        </code>
         command is in the source file.
      </para>
      <para>
        There are many options for the output. An example is that the exclamation point in
        <code>
          \index
Default handler: &lbrace;
          congruence!and Wilson's Theorem
Default handler: &rbrace;
        </code>
         produces a main entry of
        <samp>
          congruence
        </samp>
         with a subentry of
        <samp>
          and Wilson's Theorem
        </samp>
        . For more,
        <pxref label="makeindex">
          <xrefnodename>
            makeindex
          </xrefnodename>
        </pxref>
        .
      </para>
      <para>
        The
        <code>
          \makeindex
        </code>
         and
        <code>
          \printindex
        </code>
         commands are independent. Leaving out the
        <code>
          \makeindex
        </code>
         will stop
Default handler: &latex;
         from saving the index entries to the auxiliary file. Leaving out the
        <code>
          \printindex
        </code>
         will cause
Default handler: &latex;
         to not show the index in the document output.
      </para>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="1166">
          <r>
            package
          </r>
          ,
          <code>
            showidx
          </code>
        </indexterm>
      </cindex>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="1167">
          <code>
            showidx
          </code>
          <r>
            package
          </r>
        </indexterm>
      </cindex>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="1168">
          <r>
            package
          </r>
          ,
          <code>
            multind
          </code>
        </indexterm>
      </cindex>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="1169">
          <code>
            multind
          </code>
          <r>
            package
          </r>
        </indexterm>
      </cindex>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="1170">
          index, multiple
        </indexterm>
      </cindex>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="1171">
          multiple indexes
        </indexterm>
      </cindex>
      <para>
        There are many packages in the area of indexing. The
        <code>
          showidx
        </code>
         package causes each index entries to be shown in the margin on the page where the
        <code>
          \index
        </code>
         appears. This can help in preparing the index. The
        <code>
          multind
        </code>
         package, among others, supports multiple indexes. See also the
Default handler: &tex;
         FAQ entry on this topic,
        <url>
          <urefurl>
            https://www.texfaq.org/FAQ-multind
          </urefurl>
        </url>
        , and the CTAN topic,
        <url>
          <urefurl>
            https://ctan.org/topic/index-multi
          </urefurl>
        </url>
        .
      </para>
      <menu endspaces=" ">
        <menuentry>
          <menuleadingtext>
            *
          </menuleadingtext>
          <menunode>
            Produce the index manually
          </menunode>
          <menuseparator>
            ::
          </menuseparator>
          <menudescription>
            <pre xml:space="preserve">
              Alphabetize entries yourself.
            </pre>
          </menudescription>
        </menuentry>
        <menuentry>
          <menuleadingtext>
            *
          </menuleadingtext>
          <menunode>
            \index
          </menunode>
          <menuseparator>
            ::
          </menuseparator>
          <menudescription>
            <pre xml:space="preserve">
              Declare an index entry.
            </pre>
          </menudescription>
        </menuentry>
        <menuentry>
          <menuleadingtext>
            *
          </menuleadingtext>
          <menunode>
            makeindex
          </menunode>
          <menuseparator>
            ::
          </menuseparator>
          <menudescription>
            <pre xml:space="preserve">
              Alphabetize index entries automatically.
            </pre>
          </menudescription>
        </menuentry>
        <menuentry>
          <menuleadingtext>
            *
          </menuleadingtext>
          <menunode>
            \printindex
          </menunode>
          <menuseparator>
            ::
          </menuseparator>
          <menudescription>
            <pre xml:space="preserve">
              Put the index here.
            </pre>
          </menudescription>
        </menuentry>
      </menu>
      <node name="Produce-the-index-manually" spaces=" ">
        <nodename>
          Produce the index manually
        </nodename>
        <nodenext automatic="on">
          \index
        </nodenext>
        <nodeup automatic="on">
          Indexes
        </nodeup>
      </node>
      <subsection spaces=" ">
        <sectiontitle>
          Produce the index manually
        </sectiontitle>
        <cindex index="cp" spaces=" ">
          <indexterm index="cp" number="1172">
            index, producing manually
          </indexterm>
        </cindex>
        <findex index="fn" spaces=" ">
          <indexterm index="fn" number="1196" mergedindex="cp">
            theindex
          </indexterm>
        </findex>
        <para>
          Documents that are small and static can have a manually produced index. This will make a separate page labeled
          <samp>
            Index
          </samp>
          , in twocolumn format.
        </para>
        <findex index="fn" spaces=" ">
          <indexterm index="fn" number="1197" mergedindex="cp">
            <r>
              environment
            </r>
            ,
            <code>
              theindex
            </code>
          </indexterm>
        </findex>
        <findex index="fn" spaces=" ">
          <indexterm index="fn" number="1198" mergedindex="cp">
            <code>
              theindex
            </code>
            <r>
              environment
            </r>
          </indexterm>
        </findex>
        <example endspaces=" ">
          <pre xml:space="preserve">
            \begin
Default handler: &lbrace;
            theindex
Default handler: &rbrace;
             \item acorn squash, 1 \subitem maple baked, 2 \indexspace \item bacon, 3 \subitem maple baked, 4 \end
Default handler: &lbrace;
            theindex
Default handler: &rbrace;
          </pre>
        </example>
        <para>
          Note that the author must enter the page numbers, which is tedious and which will result in wrong numbers if the document changes. This is why in most cases automated methods such as
          <command>
            makeindex
          </command>
           are best.
          <xref label="Indexes">
            <xrefnodename>
              Indexes
            </xrefnodename>
          </xref>
          .
        </para>
        <findex index="fn" spaces=" ">
          <indexterm index="fn" number="1199" mergedindex="cp">
            \item
          </indexterm>
        </findex>
        <findex index="fn" spaces=" ">
          <indexterm index="fn" number="1200" mergedindex="cp">
            \subitem
          </indexterm>
        </findex>
        <findex index="fn" spaces=" ">
          <indexterm index="fn" number="1201" mergedindex="cp">
            \subsubitem
          </indexterm>
        </findex>
        <findex index="fn" spaces=" ">
          <indexterm index="fn" number="1202" mergedindex="cp">
            \indexspace
          </indexterm>
        </findex>
        <para>
          However we cover the commands for completeness, and because the automated methods are based on these commands. There are three levels of entries. As the example shows, a main entry uses
          <code>
            \item
          </code>
          , subentries use
          <code>
            \subitem
          </code>
          , and the lowest level uses
          <code>
            \subsubitem
          </code>
          . Blank lines between entries have no effect. The example above includes
          <code>
            \indexspace
          </code>
           to produce vertical space in the output that some index styles use before the first entry starting with a new letter.
        </para>
      </subsection>
      <node name="_005cindex" spaces=" ">
        <nodename>
          \index
        </nodename>
        <nodenext automatic="on">
          makeindex
        </nodenext>
        <nodeprev automatic="on">
          Produce the index manually
        </nodeprev>
        <nodeup automatic="on">
          Indexes
        </nodeup>
      </node>
      <subsection spaces=" ">
        <sectiontitle>
          <code>
            \index
          </code>
        </sectiontitle>
        <cindex index="cp" spaces=" ">
          <indexterm index="cp" number="1173">
            index entry
          </indexterm>
        </cindex>
        <findex index="fn" spaces=" ">
          <indexterm index="fn" number="1203" mergedindex="cp">
            \index
          </indexterm>
        </findex>
        <para>
          Synopsis:
        </para>
        <example endspaces=" ">
          <pre xml:space="preserve">
            \index
Default handler: &lbrace;
            <var>
              index-entry-string
            </var>
Default handler: &rbrace;
          </pre>
        </example>
        <para>
          Declare an entry in the index. This command is fragile (
          <pxref label="_005cprotect">
            <xrefnodename>
              \protect
            </xrefnodename>
          </pxref>
          ).
        </para>
        <para>
          For example, as described in
          <ref label="Indexes">
            <xrefnodename>
              Indexes
            </xrefnodename>
          </ref>
          , one way to get an index from what
Default handler: &textrsquo;
          s below is to compile the document with
          <code>
            pdflatex test
          </code>
          , then process the index entries with
          <code>
            makeindex test
          </code>
          , and then compile again with
          <code>
            pdflatex test
          </code>
          .
        </para>
        <example endspaces=" ">
          <pre xml:space="preserve">
            % file test.tex ... W~Ackermann (1896--1962).\index
Default handler: &lbrace;
            Ackermann
Default handler: &rbrace;
             ... Ackermann function\index
Default handler: &lbrace;
            Ackermann!function
Default handler: &rbrace;
             ... rate of growth\index
Default handler: &lbrace;
            Ackermann!function!growth rate
Default handler: &rbrace;
          </pre>
        </example>
        <cindex index="cp" spaces=" ">
          <indexterm index="cp" number="1174">
            index entries, subentries
          </indexterm>
        </cindex>
        <noindent/>
        <para>
          All three index entries will get a page number, such as
          <samp>
            Ackermann, 22
          </samp>
          .
Default handler: &latex;
           will format the second as a subitem of the first, on the line below it and indented, and the third as a subitem of the second. Three levels deep is as far as you can nest subentries. (If you add
          <code>
            \index
Default handler: &lbrace;
            Ackermann!function!growth rate!comparison
Default handler: &rbrace;
          </code>
           then
          <command>
            makeindex
          </command>
           says
          <samp>
            Scanning input file test.idx....done (4 entries accepted, 1 rejected)
          </samp>
           and the fourth level is silently missing from the index.)
        </para>
        <para>
          If you enter a second
          <code>
            \index
          </code>
           with the same
          <var>
            index-entry-string
          </var>
           then you will get a single index entry with two page numbers (unless they happen to fall on the same page). Thus, adding
          <code>
            as for Ackermann.\index
Default handler: &lbrace;
            Ackermann
Default handler: &rbrace;
          </code>
           later in the same document as above will give an index entry like
          <samp>
            Ackermann, 22, 151
          </samp>
          . Also, you can enter the index entries in any order, so for instance
          <code>
            \index
Default handler: &lbrace;
            Ackermann!function
Default handler: &rbrace;
          </code>
           could come before
          <code>
            \index
Default handler: &lbrace;
            Ackermann
Default handler: &rbrace;
          </code>
          .
        </para>
        <cindex index="cp" spaces=" ">
          <indexterm index="cp" number="1175">
            index, page range
          </indexterm>
        </cindex>
        <para>
          Get a page range in the output, like
          <samp>
            Hilbert, 23--27
          </samp>
          , as here.
        </para>
        <example endspaces=" ">
          <pre xml:space="preserve">
            W~Ackermann (1896--1962).\index
Default handler: &lbrace;
            Ackermann
Default handler: &rbrace;
             ... D~Hilbert (1862--1943)\index
Default handler: &lbrace;
            Ackermann!Hilbert|(
Default handler: &rbrace;
             ... disapproved of his marriage.\index
Default handler: &lbrace;
            Ackermann!Hilbert|)
Default handler: &rbrace;
          </pre>
        </example>
        <noindent/>
        <para>
          If the beginning and ending of the page range are equal then the system just gives a single page number, not a range.
        </para>
        <para>
          If you index subentries but not a main entry, as with
          <code>
            \index
Default handler: &lbrace;
            Jones!program
Default handler: &rbrace;
          </code>
           and
          <code>
            \index
Default handler: &lbrace;
            Jones!results
Default handler: &rbrace;
          </code>
          , then the output is the item
          <samp>
            Jones
          </samp>
           with no comma or page number, followed by two subitems, like
          <samp>
            program, 50
          </samp>
           and
          <samp>
            results, 51
          </samp>
          .
        </para>
        <cindex index="cp" spaces=" ">
          <indexterm index="cp" number="1176">
            see and see also index entries
          </indexterm>
        </cindex>
        <cindex index="cp" spaces=" ">
          <indexterm index="cp" number="1177">
            index entries,
Default handler: &textlsquo;
            see
Default handler: &textrsquo;
             and
Default handler: &textlsquo;
            see also
Default handler: &textrsquo;
          </indexterm>
        </cindex>
        <findex index="fn" spaces=" ">
          <indexterm index="fn" number="1204" mergedindex="cp">
            \seename
          </indexterm>
        </findex>
        <findex index="fn" spaces=" ">
          <indexterm index="fn" number="1205" mergedindex="cp">
            \alsoname
          </indexterm>
        </findex>
        <cindex index="cp" spaces=" ">
          <indexterm index="cp" number="1178">
            <r>
              package
            </r>
            ,
            <code>
              babel
            </code>
          </indexterm>
        </cindex>
        <cindex index="cp" spaces=" ">
          <indexterm index="cp" number="1179">
            <code>
              babel
            </code>
            <r>
              package
            </r>
          </indexterm>
        </cindex>
        <cindex index="cp" spaces=" ">
          <indexterm index="cp" number="1180">
            <r>
              package
            </r>
            ,
            <code>
              polyglossia
            </code>
          </indexterm>
        </cindex>
        <cindex index="cp" spaces=" ">
          <indexterm index="cp" number="1181">
            <code>
              polyglossia
            </code>
            <r>
              package
            </r>
          </indexterm>
        </cindex>
        <para>
          Generate a index entry that says
          <samp>
            see
          </samp>
           by using a vertical bar character:
          <code>
            \index
Default handler: &lbrace;
            Ackermann!function|see
Default handler: &lbrace;
            P\'eter's function
Default handler: &rbrace;
Default handler: &rbrace;
          </code>
          . You can instead get
          <samp>
            see also
          </samp>
           with
          <code>
            seealso
          </code>
          . (The text
          <samp>
            see
          </samp>
           is defined by
          <code>
            \seename
          </code>
          , and
          <samp>
            see also
          </samp>
           by
          <code>
            \alsoname
          </code>
          . You can redefine these either by using an internationalization package such as
          <code>
            babel
          </code>
           or
          <code>
            polyglossia
          </code>
          , or directly as with
          <code>
            \renewcommand
Default handler: &lbrace;
            \alsoname
Default handler: &rbrace;
Default handler: &lbrace;
            Also see
Default handler: &rbrace;
          </code>
          .)
        </para>
        <para>
          The
          <samp>
            see
          </samp>
           feature is part of a more general functionality. After the vertical bar you can put the name of a one-input command, as in
          <code>
            \index
Default handler: &lbrace;
            group|textit
Default handler: &rbrace;
          </code>
           (note the missing backslash on the
          <code>
            \textit
          </code>
           command) and the system will apply that command to the page number, here giving something like
          <code>
            \textit
Default handler: &lbrace;
            7
Default handler: &rbrace;
          </code>
          . You can define your own one-input commands, such as
          <code>
            \newcommand
Default handler: &lbrace;
            \definedpage
Default handler: &rbrace;
            [1]
Default handler: &lbrace;
Default handler: &lbrace;
            \color
Default handler: &lbrace;
            blue
Default handler: &rbrace;
            #1
Default handler: &rbrace;
Default handler: &rbrace;
          </code>
           and then
          <code>
            \index
Default handler: &lbrace;
            Ackermann!function|definedpage
Default handler: &rbrace;
          </code>
           will give a blue page number (
          <pxref label="Color">
            <xrefnodename>
              Color
            </xrefnodename>
          </pxref>
          ). Another, less practical, example is this,
        </para>
Default handler: <!-- c credit Ian Thompson https://tex.stackexchange.com/a/272572/121234 -->
        <example endspaces=" ">
          <pre xml:space="preserve">
            \newcommand\indexownpage[1]
Default handler: &lbrace;
            #1, \thepage
Default handler: &rbrace;
             ... Epimenides.\index
Default handler: &lbrace;
            self-reference|indexownpage
Default handler: &rbrace;
          </pre>
        </example>
        <noindent/>
        <para>
          which creates an entry citing the page number of its own index listing.
        </para>
        <para>
          The two functions just described combine, as here
        </para>
        <example endspaces=" ">
          <pre xml:space="preserve">
            \index
Default handler: &lbrace;
            Ackermann!function|(definedpage
Default handler: &rbrace;
             ... \index
Default handler: &lbrace;
            Ackermann!function|)
Default handler: &rbrace;
          </pre>
        </example>
        <noindent/>
        <para>
          which outputs an index entry like
          <samp>
            function, 23--27
          </samp>
           where the page number range is in blue.
        </para>
        <para>
          Consider an index entry such as
          <samp>
            <u>
              03B1
            </u>
            -ring
          </samp>
          . Entering it as
          <code>
            $\alpha$-ring
          </code>
           will cause it to be alphabetized according to the dollar sign. You can instead enter it using an at-sign, as
          <code>
            \index
Default handler: &lbrace;
            alpha-ring
Default handler: &arobase;
            $\alpha$-ring
Default handler: &rbrace;
          </code>
          . If you specify an entry with an at-sign separating two strings,
          <code>
            <var>
              pos
            </var>
Default handler: &arobase;
            <var>
              text
            </var>
          </code>
          , then
          <var>
            pos
          </var>
           gives the alphabetical position of the entry while
          <var>
            text
          </var>
           produces the text of the entry. Another example is that
          <code>
            \index
Default handler: &lbrace;
            Saint Michael's College
Default handler: &arobase;
            SMC
Default handler: &rbrace;
          </code>
           produces an index entry
          <samp>
            SMC
          </samp>
           alphabetized into a different location than its spelling would naturally give it.
        </para>
        <para>
          To put a
          <code>
            !
          </code>
          , or
          <codeDefault handler: &arobase;
/>
          , or
          <code>
            |
          </code>
          , or
          <code>
            "
          </code>
           character in an index entry, escape it by preceding it with a double quote,
          <code>
            "
          </code>
          . (The double quote gets deleted before alphabetization.)
        </para>
        <cindex index="cp" spaces=" ">
          <indexterm index="cp" number="1182">
            <r>
              package
            </r>
            ,
            <code>
              index
            </code>
          </indexterm>
        </cindex>
        <cindex index="cp" spaces=" ">
          <indexterm index="cp" number="1183">
            <code>
              index
            </code>
            <r>
              package
            </r>
          </indexterm>
        </cindex>
        <para>
          A number of packages on CTAN have additional functionality beyond that provided by
          <code>
            makeidx
          </code>
          . One is
          <code>
            index
          </code>
          , which allows for multiple indices and contains a command
          <code>
            \index*
Default handler: &lbrace;
            <var>
              index-entry-string
            </var>
Default handler: &rbrace;
          </code>
           that prints the
          <var>
            index-entry-string
          </var>
           as well as indexing it.
        </para>
        <findex index="fn" spaces=" ">
          <indexterm index="fn" number="1206" mergedindex="cp">
            \indexentry
          </indexterm>
        </findex>
        <cindex index="cp" spaces=" ">
          <indexterm index="cp" number="1184">
            idx file
          </indexterm>
        </cindex>
        <para>
          The
          <code>
            \index
          </code>
           command writes the indexing information to the file
          <file>
            <var>
              root-name
            </var>
            .idx
          </file>
           file. Specifically, it writes text of the command
          <code>
            \indexentry
Default handler: &lbrace;
            <var>
              index-entry-string
            </var>
Default handler: &rbrace;
Default handler: &lbrace;
            <var>
              page-num
            </var>
Default handler: &rbrace;
          </code>
          , where
          <var>
            page-num
          </var>
           is the value of the
          <code>
            \thepage
          </code>
           counter. On occasion, when the
          <code>
            \printindex
          </code>
           command is confused, you have to delete this file to start with a fresh slate.
        </para>
        <para>
          If you omit the closing brace of an
          <code>
            \index
          </code>
           command then you get a message like this.
        </para>
        <example endspaces=" ">
          <pre xml:space="preserve">
            Runaway argument?
Default handler: &lbrace;
            Ackermann!function ! Paragraph ended before \
Default handler: &arobase;
            wrindex was complete.
          </pre>
        </example>
      </subsection>
      <node name="makeindex" spaces=" ">
        <nodename>
          makeindex
        </nodename>
        <nodenext automatic="on">
          \printindex
        </nodenext>
        <nodeprev automatic="on">
          \index
        </nodeprev>
        <nodeup automatic="on">
          Indexes
        </nodeup>
      </node>
      <subsection spaces=" ">
        <sectiontitle>
          <command>
            makeindex
          </command>
        </sectiontitle>
        <cindex index="cp" spaces=" ">
          <indexterm index="cp" number="1185">
            index, processing
          </indexterm>
        </cindex>
        <findex index="fn" spaces=" ">
          <indexterm index="fn" number="1207" mergedindex="cp">
            makeindex,
            <r>
              program
            </r>
          </indexterm>
        </findex>
        <cindex index="cp" spaces=" ">
          <indexterm index="cp" number="1186">
            <command>
              makeindex
            </command>
             program
          </indexterm>
        </cindex>
        <cindex index="cp" spaces=" ">
          <indexterm index="cp" number="1187">
            <file>
              .ind
            </file>
             file
          </indexterm>
        </cindex>
        <cindex index="cp" spaces=" ">
          <indexterm index="cp" number="1188">
            <file>
              .idx
            </file>
             file
          </indexterm>
        </cindex>
        <para>
          Synopsis, one of:
        </para>
        <example endspaces=" ">
          <pre xml:space="preserve">
            makeindex
            <var>
              filename
            </var>
             makeindex -s
            <var>
              style-file
            </var>
            <var>
              filename
            </var>
             makeindex
            <var>
              options
            </var>
            <var>
              filename0
            </var>
             ...
          </pre>
        </example>
        <para>
          Sort, and otherwise process, the index information in the auxiliary file
          <var>
            filename
          </var>
          . This is a command line program. It takes one or more raw index files,
          <file>
            <var>
              filename
            </var>
            .idx
          </file>
           files, and produces the actual index file, the
          <file>
            <var>
              filename
            </var>
            .ind
          </file>
           file that is input by
          <code>
            \printindex
          </code>
           (
          <pxref label="_005cprintindex">
            <xrefnodename>
              \printindex
            </xrefnodename>
          </pxref>
          ).
        </para>
        <cindex index="cp" spaces=" ">
          <indexterm index="cp" number="1189">
            <file>
              .isty
            </file>
             file
          </indexterm>
        </cindex>
        <findex index="fn" spaces=" ">
          <indexterm index="fn" number="1208" mergedindex="cp">
            index, style file
          </indexterm>
        </findex>
        <findex index="fn" spaces=" ">
          <indexterm index="fn" number="1209" mergedindex="cp">
            makeindex, style file
          </indexterm>
        </findex>
        <para>
          The first form of the command suffices for many uses. The second allows you to format the index by using an
          <dfn>
            index style file
          </dfn>
          , a
          <file>
            .isty
          </file>
           file. The third form is the most general; see the full documentation on CTAN.
        </para>
        <para>
          This is a simple
          <file>
            .isty
          </file>
           file.
        </para>
        <example endspaces=" ">
          <pre xml:space="preserve">
            % book.isty % $ makeindex -s book.isty -p odd book.idx % creates the index as book.ind, starting on an odd page. preamble
            "
            \\pagestyle
Default handler: &lbrace;
            empty
Default handler: &rbrace;
             \\small \\begin
Default handler: &lbrace;
            theindex
Default handler: &rbrace;
             \\thispagestyle
Default handler: &lbrace;
            empty
Default handler: &rbrace;
            "
             postamble
            "
            \n \\end
Default handler: &lbrace;
            theindex
Default handler: &rbrace;
            "
          </pre>
        </example>
        <para>
          The description here covers only some of the index formatting possibilities in
          <var>
            style-file
          </var>
          . For a full list see the documentation on CTAN.
        </para>
        <para>
          A style file consists of a list of pairs:
          <var>
            specifier
          </var>
           and
          <var>
            attribute
          </var>
          . These can appear in the file in any order. All of the
          <var>
            attribute
          </var>
          s are strings, except where noted. Strings are surrounded with double quotes,
          <code>
            "
          </code>
          , and the maximum length of a string is 144 characters. The
          <code>
            \n
          </code>
           is for a newline and
          <code>
            \t
          </code>
           is for a tab. Backslashes are escaped with another backslash,
          <code>
            \\
          </code>
          . If a line begins with a percent sign,
          <code>
            %
          </code>
          , then it is a comment.
        </para>
        <ftable commandarg="code" spaces=" " endspaces=" ">
          <beforefirstitem>
            <anchor name="makeindex-preamble">
              makeindex preamble
            </anchor>
          </beforefirstitem>
          <tableentry>
            <tableterm>
              <item spaces=" ">
                <itemformat command="code">
                  <indexterm index="fn" number="1210" mergedindex="cp">
                    preamble
                  </indexterm>
                  preamble
                </itemformat>
              </item>
            </tableterm>
            <tableitem>
              <para>
                Preamble of the output index file. Defines the context in which the index is formatted. Default:
                <code>
                  "
                  \\begin
Default handler: &lbrace;
                  theindex
Default handler: &rbrace;
                  \n
                  "
                </code>
                .
              </para>
              <anchor name="makeindex-postamble">
                makeindex postamble
              </anchor>
            </tableitem>
          </tableentry>
          <tableentry>
            <tableterm>
              <item spaces=" ">
                <itemformat command="code">
                  <indexterm index="fn" number="1211" mergedindex="cp">
                    postamble
                  </indexterm>
                  postamble
                </itemformat>
              </item>
            </tableterm>
            <tableitem>
              <para>
                Postamble of the output index file. Default:
                <code>
                  "
                  \n\n\\end
Default handler: &lbrace;
                  theindex
Default handler: &rbrace;
                  \n
                  "
                </code>
                .
              </para>
              <anchor name="makeindex-group-skip">
                makeindex group skip
              </anchor>
            </tableitem>
          </tableentry>
          <tableentry>
            <tableterm>
              <item spaces=" ">
                <itemformat command="code">
                  <indexterm index="fn" number="1212" mergedindex="cp">
                    group_skip
                  </indexterm>
                  group_skip
                </itemformat>
              </item>
            </tableterm>
            <tableitem>
              <findex index="fn" spaces=" ">
                <indexterm index="fn" number="1213" mergedindex="cp">
                  \indexspace
                </indexterm>
              </findex>
              <para>
                Traditionally index items are broken into groups, typically a group for entries starting with letter
                <samp>
                  a
                </samp>
                , etc. This specifier gives what is inserted when a new group begins. Default:
                <code>
                  "
                  \n\n \\indexspace\n
                  "
                </code>
                 (
                <code>
                  \indexspace
                </code>
                 is a command inserting a rubber length, by default
                <code>
                  10pt plus5pt minus3pt
                </code>
                ).
              </para>
              <anchor name="makeindex-letheadflag">
                makeindex letheadflag
              </anchor>
            </tableitem>
          </tableentry>
          <tableentry>
            <tableterm>
              <item spaces=" ">
                <itemformat command="code">
                  <indexterm index="fn" number="1214" mergedindex="cp">
                    lethead_flag
                  </indexterm>
                  lethead_flag
                </itemformat>
              </item>
            </tableterm>
            <tableitem>
              <para>
                An integer. It governs what is inserted for a new group or letter. If it is 0 (which is the default) then other than
                <code>
                  group_skip
                </code>
                 nothing will be inserted before the group. If it is positive then at a new letter the
                <code>
                  lethead_prefix
                </code>
                 and
                <code>
                  lethead_suffix
                </code>
                 will be inserted, with that letter in uppercase between them. If it is negative then what will be inserted is the letter in lowercase. The default is
Default handler: &nbsp;
                0.
              </para>
              <anchor name="makeindex-lethead-prefix">
                makeindex lethead prefix
              </anchor>
            </tableitem>
          </tableentry>
          <tableentry>
            <tableterm>
              <item spaces=" ">
                <itemformat command="code">
                  <indexterm index="fn" number="1215" mergedindex="cp">
                    lethead_prefix
                  </indexterm>
                  lethead_prefix
                </itemformat>
              </item>
            </tableterm>
            <tableitem>
              <para>
                If a new group begins with a different letter then this is the prefix inserted before the new letter header. Default:
                <code>
                  "
                  "
                </code>
              </para>
              <anchor name="makeindex-lethead-suffix">
                makeindex lethead suffix
              </anchor>
            </tableitem>
          </tableentry>
          <tableentry>
            <tableterm>
              <item spaces=" ">
                <itemformat command="code">
                  <indexterm index="fn" number="1216" mergedindex="cp">
                    lethead_suffix
                  </indexterm>
                  lethead_suffix
                </itemformat>
              </item>
            </tableterm>
            <tableitem>
              <para>
                If a group begins with a different letter then this is the suffix inserted after the new letter header. Default:
                <code>
                  "
                  "
                </code>
                .
              </para>
              <anchor name="makeindex-item-0">
                makeindex item 0
              </anchor>
            </tableitem>
          </tableentry>
          <tableentry>
            <tableterm>
              <item spaces=" ">
                <itemformat command="code">
                  <indexterm index="fn" number="1217" mergedindex="cp">
                    item_0
                  </indexterm>
                  item_0
                </itemformat>
              </item>
            </tableterm>
            <tableitem>
              <para>
                What is put between two level
Default handler: &nbsp;
                0 items. Default:
                <code>
                  "
                  \n \\item
                  "
                </code>
                .
              </para>
              <anchor name="makeindex-item-1">
                makeindex item 1
              </anchor>
            </tableitem>
          </tableentry>
          <tableentry>
            <tableterm>
              <item spaces=" ">
                <itemformat command="code">
                  <indexterm index="fn" number="1218" mergedindex="cp">
                    item_1
                  </indexterm>
                  item_1
                </itemformat>
              </item>
            </tableterm>
            <tableitem>
              <para>
                Put between two level
Default handler: &nbsp;
                1 items. Default:
                <code>
                  "
                  \n \\subitem
                  "
                </code>
                .
              </para>
              <anchor name="makeindex-item-2">
                makeindex item 2
              </anchor>
            </tableitem>
          </tableentry>
          <tableentry>
            <tableterm>
              <item spaces=" ">
                <itemformat command="code">
                  <indexterm index="fn" number="1219" mergedindex="cp">
                    item_2
                  </indexterm>
                  item_2
                </itemformat>
              </item>
            </tableterm>
            <tableitem>
              <para>
                put between two level
Default handler: &nbsp;
                2 items. Default:
                <code>
                  "
                  \n \\subsubitem
                  "
                </code>
                .
              </para>
              <anchor name="makeindex-item-01">
                makeindex item 01
              </anchor>
            </tableitem>
          </tableentry>
          <tableentry>
            <tableterm>
              <item spaces=" ">
                <itemformat command="code">
                  <indexterm index="fn" number="1220" mergedindex="cp">
                    item_01
                  </indexterm>
                  item_01
                </itemformat>
              </item>
            </tableterm>
            <tableitem>
              <para>
                What is put between a level
Default handler: &nbsp;
                0 item and a level
Default handler: &nbsp;
                1 item. Default:
                <code>
                  "
                  \n \\subitem
                  "
                </code>
                .
              </para>
              <anchor name="makeindex-item-x1">
                makeindex item x1
              </anchor>
            </tableitem>
          </tableentry>
          <tableentry>
            <tableterm>
              <item spaces=" ">
                <itemformat command="code">
                  <indexterm index="fn" number="1221" mergedindex="cp">
                    item_x1
                  </indexterm>
                  item_x1
                </itemformat>
              </item>
            </tableterm>
            <tableitem>
              <para>
                What is put between a level
Default handler: &nbsp;
                0 item and a level
Default handler: &nbsp;
                1 item in the case that the level
Default handler: &nbsp;
                0 item doesn
Default handler: &textrsquo;
                t have any page numbers (as in
                <code>
                  \index
Default handler: &lbrace;
                  aaa|see
Default handler: &lbrace;
                  bbb
Default handler: &rbrace;
Default handler: &rbrace;
                </code>
                ). Default:
                <code>
                  "
                  \n \\subitem
                  "
                </code>
                .
              </para>
              <anchor name="makeindex-item-12">
                makeindex item 12
              </anchor>
            </tableitem>
          </tableentry>
          <tableentry>
            <tableterm>
              <item spaces=" ">
                <itemformat command="code">
                  <indexterm index="fn" number="1222" mergedindex="cp">
                    item_12
                  </indexterm>
                  item_12
                </itemformat>
              </item>
            </tableterm>
            <tableitem>
              <para>
                What is put between a level
Default handler: &nbsp;
                1 item and a level
Default handler: &nbsp;
                2 item. Default:
                <code>
                  "
                  \n \\subsubitem
                  "
                </code>
                .
              </para>
              <anchor name="makeindex-item-x2">
                makeindex item x2
              </anchor>
            </tableitem>
          </tableentry>
          <tableentry>
            <tableterm>
              <item spaces=" ">
                <itemformat command="code">
                  <indexterm index="fn" number="1223" mergedindex="cp">
                    item_x2
                  </indexterm>
                  item_x2
                </itemformat>
              </item>
            </tableterm>
            <tableitem>
              <para>
                What is put between a level
Default handler: &nbsp;
                1 item and a level
Default handler: &nbsp;
                2 item, if the level
Default handler: &nbsp;
                1 item doesn
Default handler: &textrsquo;
                t have page numbers. Default:
                <code>
                  "
                  \n \\subsubitem
                  "
                </code>
                .
              </para>
              <anchor name="makeindex-delim-0">
                makeindex delim 0
              </anchor>
            </tableitem>
          </tableentry>
          <tableentry>
            <tableterm>
              <item spaces=" ">
                <itemformat command="code">
                  <indexterm index="fn" number="1224" mergedindex="cp">
                    delim_0
                  </indexterm>
                  delim_0
                </itemformat>
              </item>
            </tableterm>
            <tableitem>
              <para>
                Delimiter put between a level
Default handler: &nbsp;
                0 key and its first page number. Default: a comma followed by a blank,
                <code>
                  "
                  ,
                  "
                </code>
                .
              </para>
              <anchor name="makeindex-delim-1">
                makeindex delim 1
              </anchor>
            </tableitem>
          </tableentry>
          <tableentry>
            <tableterm>
              <item spaces=" ">
                <itemformat command="code">
                  <indexterm index="fn" number="1225" mergedindex="cp">
                    delim_1
                  </indexterm>
                  delim_1
                </itemformat>
              </item>
            </tableterm>
            <tableitem>
              <para>
                Delimiter put between a level
Default handler: &nbsp;
                1 key and its first page number. Default: a comma followed by a blank,
                <code>
                  "
                  ,
                  "
                </code>
                .
              </para>
              <anchor name="makeindex-delim-2">
                makeindex delim 2
              </anchor>
            </tableitem>
          </tableentry>
          <tableentry>
            <tableterm>
              <item spaces=" ">
                <itemformat command="code">
                  <indexterm index="fn" number="1226" mergedindex="cp">
                    delim_2
                  </indexterm>
                  delim_2
                </itemformat>
              </item>
            </tableterm>
            <tableitem>
              <para>
                Delimiter between a level
Default handler: &nbsp;
                2 key and its first page number. Default: a comma followed by a blank,
                <code>
                  "
                  ,
                  "
                </code>
                .
              </para>
              <anchor name="makeindex-delim-n">
                makeindex delim n
              </anchor>
            </tableitem>
          </tableentry>
          <tableentry>
            <tableterm>
              <item spaces=" ">
                <itemformat command="code">
                  <indexterm index="fn" number="1227" mergedindex="cp">
                    delim_n
                  </indexterm>
                  delim_n
                </itemformat>
              </item>
            </tableterm>
            <tableitem>
              <para>
                Delimiter between two page numbers for the same key (at any level). Default: a comma followed by a blank,
                <code>
                  "
                  ,
                  "
                </code>
                .
              </para>
              <anchor name="makeindex-delim-r">
                makeindex delim r
              </anchor>
            </tableitem>
          </tableentry>
          <tableentry>
            <tableterm>
              <item spaces=" ">
                <itemformat command="code">
                  <indexterm index="fn" number="1228" mergedindex="cp">
                    delim_r
                  </indexterm>
                  delim_r
                </itemformat>
              </item>
            </tableterm>
            <tableitem>
              <para>
                What is put between the starting and ending page numbers of a range. Default:
                <code>
                  "
                  --
                  "
                </code>
                .
              </para>
              <anchor name="makeindex-line-max">
                makeindex line max
              </anchor>
            </tableitem>
          </tableentry>
          <tableentry>
            <tableterm>
              <item spaces=" ">
                <itemformat command="code">
                  <indexterm index="fn" number="1229" mergedindex="cp">
                    line_max
                  </indexterm>
                  line_max
                </itemformat>
              </item>
            </tableterm>
            <tableitem>
              <para>
                An integer. Maximum length of an index entry
Default handler: &textrsquo;
                s line in the output, beyond which the line wraps. Default:
                <code>
                  72
                </code>
                .
              </para>
              <anchor name="makeindex-indent-space">
                makeindex indent space
              </anchor>
            </tableitem>
          </tableentry>
          <tableentry>
            <tableterm>
              <item spaces=" ">
                <itemformat command="code">
                  <indexterm index="fn" number="1230" mergedindex="cp">
                    indent_space
                  </indexterm>
                  indent_space
                </itemformat>
              </item>
            </tableterm>
            <tableitem>
              <para>
                What is inserted at the start of a wrapped line. Default:
                <code>
                  "
                  \t\t
                  "
                </code>
                .
              </para>
              <anchor name="makeindex-indent-length">
                makeindex indent length
              </anchor>
            </tableitem>
          </tableentry>
          <tableentry>
            <tableterm>
              <item spaces=" ">
                <itemformat command="code">
                  <indexterm index="fn" number="1231" mergedindex="cp">
                    indent_length
                  </indexterm>
                  indent_length
                </itemformat>
              </item>
            </tableterm>
            <tableitem>
              <para>
                A number. The length of the wrapped line indentation. The default
                <code>
                  indent_space
                </code>
                 is two tabs and each tab is eight spaces so the default here is
                <code>
                  16
                </code>
                .
              </para>
              <anchor name="makeindex-page-precedence">
                makeindex page precedence
              </anchor>
            </tableitem>
          </tableentry>
          <tableentry>
            <tableterm>
              <item spaces=" ">
                <itemformat command="code">
                  <indexterm index="fn" number="1232" mergedindex="cp">
                    page_precedence
                  </indexterm>
                  page_precedence
                </itemformat>
              </item>
            </tableterm>
            <tableitem>
              <para>
                A document may have pages numbered in different ways. For example, a book may have front matter pages numbered in lowercase roman while main matter pages are in arabic. This string specifies the order in which they will appear in the index. The
                <command>
                  makeindex
                </command>
                 command supports five different types of numerals: lowercase roman
                <code>
                  r
                </code>
                , and numeric or arabic
                <code>
                  n
                </code>
                , and lowercase alphabetic
                <code>
                  a
                </code>
                , and uppercase roman
                <code>
                  R
                </code>
                , and uppercase alphabetic
                <code>
                  A
                </code>
                . Default:
                <code>
                  "
                  rnaRA
                  "
                </code>
                .
              </para>
            </tableitem>
          </tableentry>
        </ftable>
        <findex index="fn" spaces=" ">
          <indexterm index="fn" number="1233" mergedindex="cp">
            xindy
            <r>
              program
            </r>
          </indexterm>
        </findex>
        <para>
          There are a number of other programs that do the job
          <command>
            makeindex
          </command>
           does. One is
          <command>
            xindy
          </command>
           (
          <uref>
            <urefurl>
              https://ctan.org/pkg/xindy
            </urefurl>
          </uref>
          ), which does internationalization and can process indexes for documents marked up using
Default handler: &latex;
           and a number of other languages. It is written in Lisp, highly configurable, both in markup terms and in terms of the collating order of the text, as described in its documentation.
        </para>
        <findex index="fn" spaces=" ">
          <indexterm index="fn" number="1234" mergedindex="cp">
            xindex
            <r>
              program
            </r>
          </indexterm>
        </findex>
        <para>
          A more recent indexing program supporting Unicode is
          <code>
            xindex
          </code>
          , written in Lua (
          <url>
            <urefurl>
              https://ctan.org/pkg/xindex
            </urefurl>
          </url>
          ).
        </para>
      </subsection>
      <node name="_005cprintindex" spaces=" ">
        <nodename>
          \printindex
        </nodename>
        <nodeprev automatic="on">
          makeindex
        </nodeprev>
        <nodeup automatic="on">
          Indexes
        </nodeup>
      </node>
      <subsection spaces=" ">
        <sectiontitle>
          <command>
            \printindex
          </command>
        </sectiontitle>
        <cindex index="cp" spaces=" ">
          <indexterm index="cp" number="1190">
            index, printing
          </indexterm>
        </cindex>
        <findex index="fn" spaces=" ">
          <indexterm index="fn" number="1235" mergedindex="cp">
            \printindex
          </indexterm>
        </findex>
        <para>
          Synopsis:
        </para>
        <example endspaces=" ">
          <pre xml:space="preserve">
            \printindex
          </pre>
        </example>
        <para>
          Place the index into the output.
        </para>
        <cindex index="cp" spaces=" ">
          <indexterm index="cp" number="1191">
            <r>
              package
            </r>
            ,
            <code>
              makeidx
            </code>
          </indexterm>
        </cindex>
        <cindex index="cp" spaces=" ">
          <indexterm index="cp" number="1192">
            <code>
              makeidx
            </code>
            <r>
              package
            </r>
          </indexterm>
        </cindex>
        <para>
          To get an index you must first include
          <code>
            \usepackage
Default handler: &lbrace;
            makeidx
Default handler: &rbrace;
            \makeindex
          </code>
           in the document preamble and compile the document, then run the system command
          <command>
            makeindex
          </command>
          , and then compile the document again.
          <xref label="Indexes">
            <xrefnodename>
              Indexes
            </xrefnodename>
          </xref>
          , for further discussion and an example of the use of
          <code>
            \printindex
          </code>
          .
        </para>
      </subsection>
    </section>
    <node name="Glossaries" spaces=" ">
      <nodename>
        Glossaries
      </nodename>
      <nodeprev automatic="on">
        Indexes
      </nodeprev>
      <nodeup automatic="on">
        Front/back matter
      </nodeup>
    </node>
    <section spaces=" ">
      <sectiontitle>
        Glossaries
      </sectiontitle>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="1193">
          glossary
        </indexterm>
      </cindex>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="1194">
          glossaries
        </indexterm>
      </cindex>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="1195">
          acronyms, list of
        </indexterm>
      </cindex>
      <findex index="fn" spaces=" ">
        <indexterm index="fn" number="1236" mergedindex="cp">
          \makeglossary
        </indexterm>
      </findex>
      <findex index="fn" spaces=" ">
        <indexterm index="fn" number="1237" mergedindex="cp">
          \printglossaries
        </indexterm>
      </findex>
      <para>
        Synopsis:
      </para>
      <example endspaces=" ">
        <pre xml:space="preserve">
          \usepackage
Default handler: &lbrace;
          glossaries
Default handler: &rbrace;
           \makeglossaries ... \newglossaryentry
Default handler: &lbrace;
          <var>
            label
          </var>
Default handler: &rbrace;
Default handler: &lbrace;
          <var>
            settings
          </var>
Default handler: &rbrace;
           ... \gls
Default handler: &lbrace;
          <var>
            label
          </var>
Default handler: &rbrace;
          . ... \printglossaries
        </pre>
      </example>
      <para>
        The
        <file>
          glossaries
        </file>
         package allows you to make glossaries, including multiple glossaries, as well as lists of acronyms.
      </para>
      <para>
        To get the output from this example, compile the document (for instance with
        <code>
          pdflatex filename
        </code>
        ), then run the command line command
        <code>
          makeglossaries filename
        </code>
        , and then compile the document again.
      </para>
      <example endspaces=" ">
        <pre xml:space="preserve">
          \documentclass
Default handler: &lbrace;
          ...
Default handler: &rbrace;
           \usepackage
Default handler: &lbrace;
          glossaries
Default handler: &rbrace;
           \makeglossaries \newglossaryentry
Default handler: &lbrace;
          tm
Default handler: &rbrace;
Default handler: &lbrace;
          % name=
Default handler: &lbrace;
          Turing machine
Default handler: &rbrace;
          , description=
Default handler: &lbrace;
          A model of a machine that computes. The model is simple but can compute anything any existing device can compute. It is the standard model used in Computer Science.
Default handler: &rbrace;
          ,
Default handler: &rbrace;
           \begin
Default handler: &lbrace;
          document
Default handler: &rbrace;
           Everything begins with the definition of a \gls
Default handler: &lbrace;
          tm
Default handler: &rbrace;
          . ... \printglossaries \end
Default handler: &lbrace;
          document
Default handler: &rbrace;
        </pre>
      </example>
      <noindent/>
      <para>
        That gives two things. In the main text it outputs
        <samp>
          ... definition of a Turing machine
        </samp>
        . In addition, in a separate sectional unit headed
        <samp>
          Glossary
        </samp>
         there appears a description list. In boldface it says
        <samp>
          Turing machine
        </samp>
         and the rest of the item says in normal type
        <samp>
          A model of a machine
Default handler: &dots;
           Computer Science
        </samp>
        .
      </para>
      <findex index="fn" spaces=" ">
        <indexterm index="fn" number="1238" mergedindex="cp">
          \makeglossary
        </indexterm>
      </findex>
      <findex index="fn" spaces=" ">
        <indexterm index="fn" number="1239" mergedindex="cp">
          \printglossaries
        </indexterm>
      </findex>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="1196">
          <file>
            .glo
          </file>
           file
        </indexterm>
      </cindex>
      <para>
        The command
        <code>
          \makeglossary
        </code>
         opens the file that will contain the entry information,
        <file>
          <var>
            root-file
          </var>
          .glo
        </file>
        . Put the
        <code>
          \printglossaries
        </code>
         command where you want the glossaries to appear in your document.
      </para>
      <para>
        The
        <file>
          glossaries
        </file>
         package is very powerful. For instance, besides the commands
        <code>
          \newglossaryentry
        </code>
         and
        <code>
          \gls
        </code>
        , there are similar commands for a list of acronyms. See the package documentations on CTAN.
      </para>
      <menu endspaces=" ">
        <menuentry>
          <menuleadingtext>
            *
          </menuleadingtext>
          <menunode>
            \newglossaryentry
          </menunode>
          <menuseparator>
            ::
          </menuseparator>
          <menudescription>
            <pre xml:space="preserve">
              Declare the content of a glossary entry.
            </pre>
          </menudescription>
        </menuentry>
        <menuentry>
          <menuleadingtext>
            *
          </menuleadingtext>
          <menunode>
            \gls
          </menunode>
          <menuseparator>
            ::
          </menuseparator>
          <menudescription>
            <pre xml:space="preserve">
              Give a page reference for a glossary entry.
            </pre>
          </menudescription>
        </menuentry>
      </menu>
      <node name="_005cnewglossaryentry" spaces=" ">
        <nodename>
          \newglossaryentry
        </nodename>
        <nodenext automatic="on">
          \gls
        </nodenext>
        <nodeup automatic="on">
          Glossaries
        </nodeup>
      </node>
      <subsection spaces=" ">
        <sectiontitle>
          <code>
            \newglossaryentry
          </code>
        </sectiontitle>
        <cindex index="cp" spaces=" ">
          <indexterm index="cp" number="1197">
            glossary, entries
          </indexterm>
        </cindex>
        <findex index="fn" spaces=" ">
          <indexterm index="fn" number="1240" mergedindex="cp">
            \newglossaryentry
          </indexterm>
        </findex>
        <para>
          Synopsis, one of:
        </para>
        <example endspaces=" ">
          <pre xml:space="preserve">
            \newglossaryentry
Default handler: &lbrace;
            <var>
              label
            </var>
Default handler: &rbrace;
Default handler: &lbrace;
             name=
Default handler: &lbrace;
            <var>
              name
            </var>
Default handler: &rbrace;
            , description=
Default handler: &lbrace;
            <var>
              description
            </var>
Default handler: &rbrace;
            ,
            <var>
              other options
            </var>
            , ...
Default handler: &rbrace;
          </pre>
        </example>
        <para>
          or
        </para>
        <example endspaces=" ">
          <pre xml:space="preserve">
            \longnewglossaryentry
Default handler: &lbrace;
            <var>
              label
            </var>
Default handler: &rbrace;
Default handler: &lbrace;
             name=
Default handler: &lbrace;
            <var>
              name
            </var>
Default handler: &rbrace;
            ,
            <var>
              other options
            </var>
             ...,
Default handler: &rbrace;
Default handler: &lbrace;
            <var>
              description
            </var>
Default handler: &rbrace;
          </pre>
        </example>
        <para>
          Declare a new entry for a glossary. The
          <var>
            label
          </var>
           must be unique for the document. The settings associated with the label are pairs:
          <code>
            <var>
              key
            </var>
            =
            <var>
              value
            </var>
          </code>
          .
        </para>
        <para>
          This puts the blackboard bold symbol for the real numbers
          <u>
            211D
          </u>
          , in the glossary.
        </para>
        <example endspaces=" ">
          <pre xml:space="preserve">
            \newglossaryentry
Default handler: &lbrace;
            R
Default handler: &rbrace;
Default handler: &lbrace;
             name=
Default handler: &lbrace;
            \ensuremath
Default handler: &lbrace;
            \mathbb
Default handler: &lbrace;
            R
Default handler: &rbrace;
Default handler: &rbrace;
Default handler: &rbrace;
            , description=
Default handler: &lbrace;
            the real numbers
Default handler: &rbrace;
            ,
Default handler: &rbrace;
          </pre>
        </example>
        <para>
          Use the second command form if the
          <var>
            description
          </var>
           spans more than one paragraph.
        </para>
        <para>
          For a full list of
          <var>
            key
          </var>
          s see the package documentation on CTAN but here are a few.
        </para>
        <ftable commandarg="code" spaces=" " endspaces=" ">
          <tableentry>
            <tableterm>
              <item spaces=" ">
                <itemformat command="code">
                  <indexterm index="fn" number="1241" mergedindex="cp">
                    name
                  </indexterm>
                  name
                </itemformat>
              </item>
            </tableterm>
            <tableitem>
              <para>
                (Required.) The word, phrase, or symbol that you are defining.
              </para>
            </tableitem>
          </tableentry>
          <tableentry>
            <tableterm>
              <item spaces=" ">
                <itemformat command="code">
                  <indexterm index="fn" number="1242" mergedindex="cp">
                    description
                  </indexterm>
                  description
                </itemformat>
              </item>
            </tableterm>
            <tableitem>
              <para>
                (Required.) The description that will appear in the glossary. If this has more than one paragraph then you must use the second command form given in the synopsis.
              </para>
            </tableitem>
          </tableentry>
          <tableentry>
            <tableterm>
              <item spaces=" ">
                <itemformat command="code">
                  <indexterm index="fn" number="1243" mergedindex="cp">
                    plural
                  </indexterm>
                  plural
                </itemformat>
              </item>
            </tableterm>
            <tableitem>
              <para>
                The plural form of
                <var>
                  name
                </var>
                . Refer to the plural form using
                <code>
                  \glspl
                </code>
                 or
                <code>
                  \Glspl
                </code>
                 (
                <pxref label="_005cgls">
                  <xrefnodename>
                    \gls
                  </xrefnodename>
                </pxref>
                ).
              </para>
            </tableitem>
          </tableentry>
          <tableentry>
            <tableterm>
              <item spaces=" ">
                <itemformat command="code">
                  <indexterm index="fn" number="1244" mergedindex="cp">
                    sort
                  </indexterm>
                  sort
                </itemformat>
              </item>
            </tableterm>
            <tableitem>
              <para>
                How to place this entry in the list of entries that the glossary holds.
              </para>
            </tableitem>
          </tableentry>
          <tableentry>
            <tableterm>
              <item spaces=" ">
                <itemformat command="code">
                  <indexterm index="fn" number="1245" mergedindex="cp">
                    symbol
                  </indexterm>
                  symbol
                </itemformat>
              </item>
            </tableterm>
            <tableitem>
              <para>
                A symbol, such as a mathematical symbol, besides the name.
              </para>
            </tableitem>
          </tableentry>
        </ftable>
      </subsection>
      <node name="_005cgls" spaces=" ">
        <nodename>
          \gls
        </nodename>
        <nodeprev automatic="on">
          \newglossaryentry
        </nodeprev>
        <nodeup automatic="on">
          Glossaries
        </nodeup>
      </node>
      <subsection spaces=" ">
        <sectiontitle>
          <code>
            \gls
          </code>
        </sectiontitle>
        <cindex index="cp" spaces=" ">
          <indexterm index="cp" number="1198">
            glossary, entry reference
          </indexterm>
        </cindex>
        <findex index="fn" spaces=" ">
          <indexterm index="fn" number="1246" mergedindex="cp">
            \gls
          </indexterm>
        </findex>
        <para>
          Synopsis, one of:
        </para>
        <example endspaces=" ">
          <pre xml:space="preserve">
            \gls
Default handler: &lbrace;
            <var>
              label
            </var>
Default handler: &rbrace;
             \glspl
Default handler: &lbrace;
            <var>
              label
            </var>
Default handler: &rbrace;
             \Gls
Default handler: &lbrace;
            <var>
              label
            </var>
Default handler: &rbrace;
             \Glspl
Default handler: &lbrace;
            <var>
              label
            </var>
Default handler: &rbrace;
          </pre>
        </example>
        <para>
          Refer to a glossary entry. The entries are declared with
          <code>
            \newglossaryentry
          </code>
           (
          <pxref label="_005cnewglossaryentry">
            <xrefnodename>
              \newglossaryentry
            </xrefnodename>
          </pxref>
          ).
        </para>
        <para>
          This
        </para>
        <example endspaces=" ">
          <pre xml:space="preserve">
            \newglossaryentry
Default handler: &lbrace;
            N
Default handler: &rbrace;
Default handler: &lbrace;
            % name=
Default handler: &lbrace;
            the natural numbers
Default handler: &rbrace;
            , description=
Default handler: &lbrace;
            The numbers $0$, $1$, $2$, $\ldots$\
Default handler: &arobase;
Default handler: &rbrace;
            , symbol=
Default handler: &lbrace;
            \ensuremath
Default handler: &lbrace;
            \mathbb
Default handler: &lbrace;
            N
Default handler: &rbrace;
Default handler: &rbrace;
Default handler: &rbrace;
            ,
Default handler: &rbrace;
             ... Consider \gls
Default handler: &lbrace;
            N
Default handler: &rbrace;
            .
          </pre>
        </example>
        <noindent/>
        <para>
          gives the output
          <samp>
            Consider the natural numbers
          </samp>
          .
        </para>
        <para>
          The second command form
          <code>
            \glspl
Default handler: &lbrace;
            <var>
              label
            </var>
Default handler: &rbrace;
          </code>
           produces the plural of
          <var>
            name
          </var>
           (by default it tries adding an
          <samp>
            s
          </samp>
          ). The third form capitalizes the first letter of
          <var>
            name
          </var>
          , as does the fourth form, which also takes the plural.
        </para>
      </subsection>
    </section>
  </chapter>
  <node name="Letters" spaces=" ">
    <nodename>
      Letters
    </nodename>
    <nodenext automatic="on">
      Input/output
    </nodenext>
    <nodeprev automatic="on">
      Front/back matter
    </nodeprev>
    <nodeup automatic="on">
      Top
    </nodeup>
  </node>
  <chapter spaces=" ">
    <sectiontitle>
      Letters
    </sectiontitle>
    <cindex index="cp" spaces=" ">
      <indexterm index="cp" number="1199">
        letters, writing
      </indexterm>
    </cindex>
    <cindex index="cp" spaces=" ">
      <indexterm index="cp" number="1200">
        writing letters
      </indexterm>
    </cindex>
    <para>
      Synopsis:
    </para>
    <example endspaces=" ">
      <pre xml:space="preserve">
        \documentclass
Default handler: &lbrace;
        letter
Default handler: &rbrace;
         \address
Default handler: &lbrace;
        <var>
          senders address
        </var>
Default handler: &rbrace;
         % return address \signature
Default handler: &lbrace;
        <var>
          sender name
        </var>
Default handler: &rbrace;
         \begin
Default handler: &lbrace;
        document
Default handler: &rbrace;
         \begin
Default handler: &lbrace;
        letter
Default handler: &rbrace;
Default handler: &lbrace;
        <var>
          recipient address
        </var>
Default handler: &rbrace;
         \opening
Default handler: &lbrace;
        <var>
          salutation
        </var>
Default handler: &rbrace;
        <var>
          letter body
        </var>
         \closing
Default handler: &lbrace;
        <var>
          closing text
        </var>
Default handler: &rbrace;
         \end
Default handler: &lbrace;
        letter
Default handler: &rbrace;
         ... \end
Default handler: &lbrace;
        document
Default handler: &rbrace;
      </pre>
    </example>
    <para>
      Produce one or more letters.
    </para>
    <para>
      Each letter is in a separate
      <code>
        letter
      </code>
       environment, whose argument
      <var>
        recipient address
      </var>
       often contains multiple lines separated with a double backslash,
Default handler: &nbsp;
      (
      <code>
        \\
      </code>
      ). For example, you might have:
    </para>
    <example endspaces=" ">
      <pre xml:space="preserve">
         \begin
Default handler: &lbrace;
        letter
Default handler: &rbrace;
Default handler: &lbrace;
        Ninon de l'Enclos \\ l'h\^otel Sagonne
Default handler: &rbrace;
         ... \end
Default handler: &lbrace;
        letter
Default handler: &rbrace;
      </pre>
    </example>
    <para>
      The start of the
      <code>
        letter
      </code>
       environment resets the page number to 1, and the footnote number to 1 also.
    </para>
    <para>
      The
      <var>
        sender address
      </var>
       and
      <var>
        sender name
      </var>
       are common to all of the letters, whether there is one or more, so these are best put in the preamble. As with the recipient address, often
      <var>
        sender address
      </var>
       contains multiple lines separated by a double backslash
Default handler: &nbsp;
      (
      <code>
        \\
      </code>
      ).
Default handler: &latex;
       will put the
      <var>
        sender name
      </var>
       under the closing, after a vertical space for the traditional hand-written signature.
    </para>
    <para>
      Each
      <code>
        letter
      </code>
       environment body begins with a required
      <code>
        \opening
      </code>
       command such as
      <code>
        \opening
Default handler: &lbrace;
        Dear Madam or Sir:
Default handler: &rbrace;
      </code>
      . The
      <var>
        letter body
      </var>
       text is ordinary
Default handler: &latex;
       so it can contain everything from enumerated lists to displayed math, except that commands such as
      <code>
        \chapter
      </code>
       that make no sense in a letter are turned off. Each
      <code>
        letter
      </code>
       environment body typically ends with a
      <code>
        \closing
      </code>
       command such as
      <code>
        \closing
Default handler: &lbrace;
        Yours,
Default handler: &rbrace;
      </code>
      .
    </para>
    <findex index="fn" spaces=" ">
      <indexterm index="fn" number="1247" mergedindex="cp">
        \\
        <r>
          (for letters)
        </r>
      </indexterm>
    </findex>
    <para>
      Additional material may come after the
      <code>
        \closing
      </code>
      . You can say who is receiving a copy of the letter with a command like
      <code>
        \cc
Default handler: &lbrace;
        the Boss \\ the Boss's Boss
Default handler: &rbrace;
      </code>
      . There
Default handler: &textrsquo;
      s a similar
      <code>
        \encl
      </code>
       command for a list of enclosures. And, you can add a postscript with
      <code>
        \ps
      </code>
      .
    </para>
    <paraDefault handler: &latex;
Default handler: &textrsquo;
>
      s default is to indent the sender name and the closing above it by a length of
      <code>
        \longindentation
      </code>
      . By default this is
      <code>
        0.5\textwidth
      </code>
      . To make them flush left, put
      <code>
        \setlength
Default handler: &lbrace;
        \longindentation
Default handler: &rbrace;
Default handler: &lbrace;
        0em
Default handler: &rbrace;
      </code>
       in your preamble.
    </para>
    <para>
      To set a fixed date use something like
      <code>
        \renewcommand
Default handler: &lbrace;
        \today
Default handler: &rbrace;
Default handler: &lbrace;
        1958-Oct-12
Default handler: &rbrace;
      </code>
      . If put in your preamble then it will apply to all the letters.
    </para>
    <para>
      This example shows only one
      <code>
        letter
      </code>
       environment. The three lines marked as optional are typically omitted.
    </para>
    <example endspaces=" ">
      <pre xml:space="preserve">
        \documentclass
Default handler: &lbrace;
        letter
Default handler: &rbrace;
         \address
Default handler: &lbrace;
        Sender's street \\ Sender's town
Default handler: &rbrace;
         \signature
Default handler: &lbrace;
        Sender's name \\ Sender's title
Default handler: &rbrace;
         % optional: \location
Default handler: &lbrace;
        Mailbox 13
Default handler: &rbrace;
         % optional: \telephone
Default handler: &lbrace;
        (102) 555-0101
Default handler: &rbrace;
         \begin
Default handler: &lbrace;
        document
Default handler: &rbrace;
         \begin
Default handler: &lbrace;
        letter
Default handler: &rbrace;
Default handler: &lbrace;
        Recipient's name \\ Recipient's address
Default handler: &rbrace;
         \opening
Default handler: &lbrace;
        Sir:
Default handler: &rbrace;
         % optional: \thispagestyle
Default handler: &lbrace;
        firstpage
Default handler: &rbrace;
         I am not interested in entering a business arrangement with you. \closing
Default handler: &lbrace;
        Your most humble, etc.,
Default handler: &rbrace;
         \end
Default handler: &lbrace;
        letter
Default handler: &rbrace;
         \end
Default handler: &lbrace;
        document
Default handler: &rbrace;
      </pre>
    </example>
    <para>
      These commands are used with the
      <code>
        letter
      </code>
       class.
    </para>
    <menu endspaces=" ">
      <menuentry>
        <menuleadingtext>
          *
        </menuleadingtext>
        <menunode>
          \address
        </menunode>
        <menuseparator>
          ::
        </menuseparator>
        <menudescription>
          <pre xml:space="preserve">
            Sender
Default handler: &textrsquo;
            s return address.
          </pre>
        </menudescription>
      </menuentry>
      <menuentry>
        <menuleadingtext>
          *
        </menuleadingtext>
        <menunode>
          \cc
        </menunode>
        <menuseparator>
          ::
        </menuseparator>
        <menudescription>
          <pre xml:space="preserve">
            Carbon copy list.
          </pre>
        </menudescription>
      </menuentry>
      <menuentry>
        <menuleadingtext>
          *
        </menuleadingtext>
        <menunode>
          \closing
        </menunode>
        <menuseparator>
          ::
        </menuseparator>
        <menudescription>
          <pre xml:space="preserve">
            Saying goodbye.
          </pre>
        </menudescription>
      </menuentry>
      <menuentry>
        <menuleadingtext>
          *
        </menuleadingtext>
        <menunode>
          \encl
        </menunode>
        <menuseparator>
          ::
        </menuseparator>
        <menudescription>
          <pre xml:space="preserve">
            List of enclosed material.
          </pre>
        </menudescription>
      </menuentry>
      <menuentry>
        <menuleadingtext>
          *
        </menuleadingtext>
        <menunode>
          \location
        </menunode>
        <menuseparator>
          ::
        </menuseparator>
        <menudescription>
          <pre xml:space="preserve">
            Sender
Default handler: &textrsquo;
            s organizational location.
          </pre>
        </menudescription>
      </menuentry>
      <menuentry>
        <menuleadingtext>
          *
        </menuleadingtext>
        <menunode>
          \makelabels
        </menunode>
        <menuseparator>
          ::
        </menuseparator>
        <menudescription>
          <pre xml:space="preserve">
            Make address labels.
          </pre>
        </menudescription>
      </menuentry>
      <menuentry>
        <menuleadingtext>
          *
        </menuleadingtext>
        <menunode>
          \name
        </menunode>
        <menuseparator>
          ::
        </menuseparator>
        <menudescription>
          <pre xml:space="preserve">
            Sender
Default handler: &textrsquo;
            s name, for the return address.
          </pre>
        </menudescription>
      </menuentry>
      <menuentry>
        <menuleadingtext>
          *
        </menuleadingtext>
        <menunode>
          \opening
        </menunode>
        <menuseparator>
          ::
        </menuseparator>
        <menudescription>
          <pre xml:space="preserve">
            Saying hello.
          </pre>
        </menudescription>
      </menuentry>
      <menuentry>
        <menuleadingtext>
          *
        </menuleadingtext>
        <menunode>
          \ps
        </menunode>
        <menuseparator>
          ::
        </menuseparator>
        <menudescription>
          <pre xml:space="preserve">
            Adding a postscript.
          </pre>
        </menudescription>
      </menuentry>
      <menuentry>
        <menuleadingtext>
          *
        </menuleadingtext>
        <menunode>
          \signature
        </menunode>
        <menuseparator>
          ::
        </menuseparator>
        <menudescription>
          <pre xml:space="preserve">
            Sender
Default handler: &textrsquo;
            s signature.
          </pre>
        </menudescription>
      </menuentry>
      <menuentry>
        <menuleadingtext>
          *
        </menuleadingtext>
        <menunode>
          \telephone
        </menunode>
        <menuseparator>
          ::
        </menuseparator>
        <menudescription>
          <pre xml:space="preserve">
            Sender
Default handler: &textrsquo;
            s phone number.
          </pre>
        </menudescription>
      </menuentry>
    </menu>
    <node name="_005caddress" spaces=" ">
      <nodename>
        \address
      </nodename>
      <nodenext automatic="on">
        \cc
      </nodenext>
      <nodeup automatic="on">
        Letters
      </nodeup>
    </node>
    <section spaces=" ">
      <sectiontitle>
        <code>
          \address
        </code>
      </sectiontitle>
      <findex index="fn" spaces=" ">
        <indexterm index="fn" number="1248" mergedindex="cp">
          \address
        </indexterm>
      </findex>
      <para>
        Synopsis:
      </para>
      <example endspaces=" ">
        <pre xml:space="preserve">
          \address
Default handler: &lbrace;
          <var>
            senders address
          </var>
Default handler: &rbrace;
        </pre>
      </example>
      <para>
        Specify the return address, as it appears on the letter and on the envelope. Separate multiple lines in
        <var>
          senders address
        </var>
         with a double backslash,
Default handler: &nbsp;
        <code>
          \\
        </code>
        .
      </para>
      <para>
        Because it can apply to multiple letters this declaration is often put in the preamble. However, it can go anywhere, including inside an individual
        <code>
          letter
        </code>
         environment.
      </para>
      <para>
        This command is optional: if you do not use it then the letter is formatted with some blank space on top, for copying onto pre-printed letterhead paper. If you do use the
        <code>
          \address
        </code>
         declaration then it is formatted as a personal letter.
      </para>
      <para>
        Here is an example.
      </para>
      <example endspaces=" ">
        <pre xml:space="preserve">
          \address
Default handler: &lbrace;
          Stephen Maturin \\ The Grapes of the Savoy
Default handler: &rbrace;
        </pre>
      </example>
    </section>
    <node name="_005ccc" spaces=" ">
      <nodename>
        \cc
      </nodename>
      <nodenext automatic="on">
        \closing
      </nodenext>
      <nodeprev automatic="on">
        \address
      </nodeprev>
      <nodeup automatic="on">
        Letters
      </nodeup>
    </node>
    <section spaces=" ">
      <sectiontitle>
        <code>
          \cc
        </code>
      </sectiontitle>
      <findex index="fn" spaces=" ">
        <indexterm index="fn" number="1249" mergedindex="cp">
          \cc
        </indexterm>
      </findex>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="1201">
          cc list, in letters
        </indexterm>
      </cindex>
      <para>
        Synopsis:
      </para>
      <example endspaces=" ">
        <pre xml:space="preserve">
          \cc
Default handler: &lbrace;
          <var>
            name0
          </var>
           \\ ...
Default handler: &rbrace;
        </pre>
      </example>
      <para>
        Produce a list of names to which copies of the letter were sent. This command is optional. If it appears then typically it comes after
        <code>
          \closing
        </code>
        . Put the names on different lines by separating them with a double backslash,
        <code>
          \\
        </code>
        , as in:
      </para>
      <example endspaces=" ">
        <pre xml:space="preserve">
          \cc
Default handler: &lbrace;
          President \\ Vice President
Default handler: &rbrace;
        </pre>
      </example>
    </section>
    <node name="_005cclosing" spaces=" ">
      <nodename>
        \closing
      </nodename>
      <nodenext automatic="on">
        \encl
      </nodenext>
      <nodeprev automatic="on">
        \cc
      </nodeprev>
      <nodeup automatic="on">
        Letters
      </nodeup>
    </node>
    <section spaces=" ">
      <sectiontitle>
        <code>
          \closing
        </code>
      </sectiontitle>
      <findex index="fn" spaces=" ">
        <indexterm index="fn" number="1250" mergedindex="cp">
          \closing
        </indexterm>
      </findex>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="1202">
          letters, ending
        </indexterm>
      </cindex>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="1203">
          closing letters
        </indexterm>
      </cindex>
      <para>
        Synopsis:
      </para>
      <example endspaces=" ">
        <pre xml:space="preserve">
          \closing
Default handler: &lbrace;
          <var>
            text
          </var>
Default handler: &rbrace;
        </pre>
      </example>
      <para>
        Produce the letter
Default handler: &textrsquo;
        s closing. This is optional, but usual. It appears at the end of a letter, above a handwritten signature. For example:
      </para>
      <example endspaces=" ">
        <pre xml:space="preserve">
          \closing
Default handler: &lbrace;
          Regards,
Default handler: &rbrace;
        </pre>
      </example>
    </section>
    <node name="_005cencl" spaces=" ">
      <nodename>
        \encl
      </nodename>
      <nodenext automatic="on">
        \location
      </nodenext>
      <nodeprev automatic="on">
        \closing
      </nodeprev>
      <nodeup automatic="on">
        Letters
      </nodeup>
    </node>
    <section spaces=" ">
      <sectiontitle>
        <code>
          \encl
        </code>
      </sectiontitle>
      <findex index="fn" spaces=" ">
        <indexterm index="fn" number="1251" mergedindex="cp">
          \encl
        </indexterm>
      </findex>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="1204">
          enclosure list
        </indexterm>
      </cindex>
      <para>
        Synopsis:
      </para>
      <example endspaces=" ">
        <pre xml:space="preserve">
          \encl
Default handler: &lbrace;
          <var>
            first enclosed object
          </var>
           \\ ...
Default handler: &rbrace;
        </pre>
      </example>
      <para>
        Produce a list of things included with the letter. This command is optional; when it is used, it typically is put after
        <code>
          \closing
        </code>
        . Separate multiple lines with a double backslash,
        <code>
          \\
        </code>
        .
      </para>
      <example endspaces=" ">
        <pre xml:space="preserve">
          \encl
Default handler: &lbrace;
          License \\ Passport
Default handler: &rbrace;
        </pre>
      </example>
    </section>
    <node name="_005clocation" spaces=" ">
      <nodename>
        \location
      </nodename>
      <nodenext automatic="on">
        \makelabels
      </nodenext>
      <nodeprev automatic="on">
        \encl
      </nodeprev>
      <nodeup automatic="on">
        Letters
      </nodeup>
    </node>
    <section spaces=" ">
      <sectiontitle>
        <code>
          \location
        </code>
      </sectiontitle>
      <findex index="fn" spaces=" ">
        <indexterm index="fn" number="1252" mergedindex="cp">
          \location
        </indexterm>
      </findex>
      <para>
        Synopsis:
      </para>
      <example endspaces=" ">
        <pre xml:space="preserve">
          \location
Default handler: &lbrace;
          <var>
            text
          </var>
Default handler: &rbrace;
        </pre>
      </example>
      <para>
        The
        <var>
          text
        </var>
         appears centered at the bottom of the page. It only appears if the page style is
        <code>
          firstpage
        </code>
        .
      </para>
    </section>
    <node name="_005cmakelabels" spaces=" ">
      <nodename>
        \makelabels
      </nodename>
      <nodenext automatic="on">
        \name
      </nodenext>
      <nodeprev automatic="on">
        \location
      </nodeprev>
      <nodeup automatic="on">
        Letters
      </nodeup>
    </node>
    <section spaces=" ">
      <sectiontitle>
        <code>
          \makelabels
        </code>
      </sectiontitle>
      <findex index="fn" spaces=" ">
        <indexterm index="fn" number="1253" mergedindex="cp">
          \makelabels
        </indexterm>
      </findex>
      <para>
        Synopsis:
      </para>
      <example endspaces=" ">
        <pre xml:space="preserve">
          \makelabels % in preamble
        </pre>
      </example>
      <para>
        Optional, for a document that contains
        <code>
          letter
        </code>
         environments. If you just put
        <code>
          \makelabels
        </code>
         in the preamble then at the end of the document you will get a sheet with labels for all the recipients, one for each letter environment, that you can copy to a sheet of peel-off address labels.
      </para>
      <para>
        Customize the labels by redefining the commands
        <code>
          \startlabels
        </code>
        ,
        <code>
          \mlabel
        </code>
        , and
        <code>
          \returnaddress
        </code>
         (and perhaps
        <code>
          \name
        </code>
        ) in the preamble. The command
        <code>
          \startlabels
        </code>
         sets the width, height, number of columns, etc., of the page onto which the labels are printed. The command
        <code>
          \mlabel
Default handler: &lbrace;
          <var>
            return address
          </var>
Default handler: &rbrace;
Default handler: &lbrace;
          <var>
            recipient address
          </var>
Default handler: &rbrace;
        </code>
         produces the two labels (or one, if you choose to ignore the
        <var>
          return address
        </var>
        ) for each letter environment. The first argument,
        <var>
          return address
        </var>
        , is the value returned by the macro
        <code>
          \returnaddress
        </code>
        . The second argument,
        <var>
          recipient address
        </var>
        , is the value passed in the argument to the
        <code>
          letter
        </code>
         environment. By default
        <code>
          \mlabel
        </code>
         ignores the first argument, the
        <var>
          return address
        </var>
        , causing the default behavior described in the prior paragraph.
      </para>
      <para>
        This illustrates customization. Its output includes a page with two columns having two labels each.
      </para>
      <example endspaces=" ">
        <pre xml:space="preserve">
          \documentclass
Default handler: &lbrace;
          letter
Default handler: &rbrace;
           \renewcommand*
Default handler: &lbrace;
          \returnaddress
Default handler: &rbrace;
Default handler: &lbrace;
          Fred McGuilicuddy \\ Oshkosh, Mineola 12305
Default handler: &rbrace;
           \newcommand*\originalMlabel
Default handler: &lbrace;
Default handler: &rbrace;
           \let\originalMlabel\mlabel \def\mlabel#1#2
Default handler: &lbrace;
          \originalMlabel
Default handler: &lbrace;
Default handler: &rbrace;
Default handler: &lbrace;
          #1
Default handler: &rbrace;
          \originalMlabel
Default handler: &lbrace;
Default handler: &rbrace;
Default handler: &lbrace;
          #2
Default handler: &rbrace;
Default handler: &rbrace;
           \makelabels ... \begin
Default handler: &lbrace;
          document
Default handler: &rbrace;
           \begin
Default handler: &lbrace;
          letter
Default handler: &rbrace;
Default handler: &lbrace;
          A Einstein \\ 112 Mercer Street \\ Princeton, New Jersey, USA 08540
Default handler: &rbrace;
           ... \end
Default handler: &lbrace;
          letter
Default handler: &rbrace;
           \begin
Default handler: &lbrace;
          letter
Default handler: &rbrace;
Default handler: &lbrace;
          K G\
          "
          odel \\ 145 Linden Lane \\ Princeton, New Jersey, USA 08540
Default handler: &rbrace;
           ... \end
Default handler: &lbrace;
          letter
Default handler: &rbrace;
           \end
Default handler: &lbrace;
          document
Default handler: &rbrace;
        </pre>
      </example>
      <noindent/>
      <para>
        The first column contains the return address twice. The second column contains the address for each recipient.
      </para>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="1205">
          <r>
            package
          </r>
          ,
          <code>
            envlab
          </code>
        </indexterm>
      </cindex>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="1206">
          <code>
            envlab
          </code>
          <r>
            package
          </r>
        </indexterm>
      </cindex>
      <para>
        The package
        <code>
          envlab
        </code>
         makes formatting the labels easier, with standard sizes already provided. The preamble lines
        <code>
          \usepackage[personalenvelope]
Default handler: &lbrace;
          envlab
Default handler: &rbrace;
        </code>
         and
        <code>
          \makelabels
        </code>
         are all that you need to print envelopes.
      </para>
    </section>
    <node name="_005cname" spaces=" ">
      <nodename>
        \name
      </nodename>
      <nodenext automatic="on">
        \opening
      </nodenext>
      <nodeprev automatic="on">
        \makelabels
      </nodeprev>
      <nodeup automatic="on">
        Letters
      </nodeup>
    </node>
    <section spaces=" ">
      <sectiontitle>
        <code>
          \name
        </code>
      </sectiontitle>
      <findex index="fn" spaces=" ">
        <indexterm index="fn" number="1254" mergedindex="cp">
          \name
        </indexterm>
      </findex>
      <para>
        Synopsis:
      </para>
      <example endspaces=" ">
        <pre xml:space="preserve">
          \name
Default handler: &lbrace;
          <var>
            name
          </var>
Default handler: &rbrace;
        </pre>
      </example>
      <para>
        Optional. Sender
Default handler: &textrsquo;
        s name, used for printing on the envelope together with the return address.
      </para>
    </section>
    <node name="_005copening" spaces=" ">
      <nodename>
        \opening
      </nodename>
      <nodenext automatic="on">
        \ps
      </nodenext>
      <nodeprev automatic="on">
        \name
      </nodeprev>
      <nodeup automatic="on">
        Letters
      </nodeup>
    </node>
    <section spaces=" ">
      <sectiontitle>
        <code>
          \opening
        </code>
      </sectiontitle>
      <findex index="fn" spaces=" ">
        <indexterm index="fn" number="1255" mergedindex="cp">
          \opening
        </indexterm>
      </findex>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="1207">
          letters, starting
        </indexterm>
      </cindex>
      <para>
        Synopsis:
      </para>
      <example endspaces=" ">
        <pre xml:space="preserve">
          \opening
Default handler: &lbrace;
          <var>
            salutation
          </var>
Default handler: &rbrace;
        </pre>
      </example>
      <para>
        Required. Follows the
        <code>
          \begin
Default handler: &lbrace;
          letter
Default handler: &rbrace;
Default handler: &lbrace;
          ...
Default handler: &rbrace;
        </code>
        . The argument
        <var>
          salutation
        </var>
         is mandatory. For instance:
      </para>
      <example endspaces=" ">
        <pre xml:space="preserve">
          \opening
Default handler: &lbrace;
          Dear John:
Default handler: &rbrace;
        </pre>
      </example>
    </section>
    <node name="_005cps" spaces=" ">
      <nodename>
        \ps
      </nodename>
      <nodenext automatic="on">
        \signature
      </nodenext>
      <nodeprev automatic="on">
        \opening
      </nodeprev>
      <nodeup automatic="on">
        Letters
      </nodeup>
    </node>
    <section spaces=" ">
      <sectiontitle>
        <code>
          \ps
        </code>
      </sectiontitle>
      <findex index="fn" spaces=" ">
        <indexterm index="fn" number="1256" mergedindex="cp">
          \ps
        </indexterm>
      </findex>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="1208">
          postscript, in letters
        </indexterm>
      </cindex>
      <para>
        Synopsis:
      </para>
      <example endspaces=" ">
        <pre xml:space="preserve">
          \ps
Default handler: &lbrace;
          <var>
            text
          </var>
Default handler: &rbrace;
        </pre>
      </example>
      <para>
        Add a postscript. This command is optional and usually is used after
        <code>
          \closing
        </code>
        .
      </para>
      <example endspaces=" ">
        <pre xml:space="preserve">
          \ps
Default handler: &lbrace;
          P.S. After you have read this letter, burn it. Or eat it.
Default handler: &rbrace;
        </pre>
      </example>
    </section>
    <node name="_005csignature" spaces=" ">
      <nodename>
        \signature
      </nodename>
      <nodenext automatic="on">
        \telephone
      </nodenext>
      <nodeprev automatic="on">
        \ps
      </nodeprev>
      <nodeup automatic="on">
        Letters
      </nodeup>
    </node>
    <section spaces=" ">
      <sectiontitle>
        <code>
          \signature
        </code>
      </sectiontitle>
      <para>
        Synopsis:
      </para>
      <example endspaces=" ">
        <pre xml:space="preserve">
          \signature
Default handler: &lbrace;
          <var>
            first line
          </var>
           \\ ...
Default handler: &rbrace;
        </pre>
      </example>
      <findex index="fn" spaces=" ">
        <indexterm index="fn" number="1257" mergedindex="cp">
          \signature
        </indexterm>
      </findex>
      <para>
        The sender
Default handler: &textrsquo;
        s name. This command is optional, although its inclusion is usual.
      </para>
      <para>
        The argument text appears at the end of the letter, after the closing.
Default handler: &latex;
         leaves some vertical space for a handwritten signature. Separate multiple lines with a double backslash,
Default handler: &nbsp;
        <code>
          \\
        </code>
        . For example:
      </para>
      <example endspaces=" ">
        <pre xml:space="preserve">
          \signature
Default handler: &lbrace;
          J Fred Muggs \\ White House
Default handler: &rbrace;
        </pre>
      </example>
      <paraDefault handler: &latex;
Default handler: &textrsquo;
>
        s default for the vertical space from the
        <code>
          \closing
        </code>
         text down to the
        <code>
          \signature
        </code>
         text is
        <code>
          6\medskipamount
        </code>
        , which is six times
        <code>
          \medskipamount
        </code>
         (where
        <code>
          \medskipamount
        </code>
         is equal to a
        <code>
          \parskip
        </code>
        , which in turn is defined by default here to 0.7
        <dmn>
          em
        </dmn>
        ).
      </para>
      <para>
        This command is usually in the preamble, to apply to all the letters in the document. To have it apply to one letter only, put it inside a
        <code>
          letter
        </code>
         environment and before the
        <code>
          \closing
        </code>
        .
      </para>
      <para>
        You can include a graphic in the signature as here.
      </para>
      <example endspaces=" ">
        <pre xml:space="preserve">
          \signature
Default handler: &lbrace;
          \vspace
Default handler: &lbrace;
          -6\medskipamount
Default handler: &rbrace;
          \includegraphics
Default handler: &lbrace;
          sig.png
Default handler: &rbrace;
          \\ My name
Default handler: &rbrace;
        </pre>
      </example>
      <noindent/>
      <para>
        For this you must put
        <code>
          \usepackage
Default handler: &lbrace;
          graphicx
Default handler: &rbrace;
        </code>
         in the preamble (
        <pxref label="Graphics">
          <xrefnodename>
            Graphics
          </xrefnodename>
        </pxref>
        ).
      </para>
    </section>
    <node name="_005ctelephone" spaces=" ">
      <nodename>
        \telephone
      </nodename>
      <nodeprev automatic="on">
        \signature
      </nodeprev>
      <nodeup automatic="on">
        Letters
      </nodeup>
    </node>
    <section spaces=" ">
      <sectiontitle>
        <code>
          \telephone
        </code>
      </sectiontitle>
      <findex index="fn" spaces=" ">
        <indexterm index="fn" number="1258" mergedindex="cp">
          \telephone
        </indexterm>
      </findex>
      <para>
        Synopsis:
      </para>
      <example endspaces=" ">
        <pre xml:space="preserve">
          \telephone
Default handler: &lbrace;
          <var>
            number
          </var>
Default handler: &rbrace;
        </pre>
      </example>
      <para>
        The sender
Default handler: &textrsquo;
        s telephone number. This is typically in the preamble, where it applies to all letters. This only appears if the
        <code>
          firstpage
        </code>
         pagestyle is selected. If so, it appears on the lower right of the page.
      </para>
    </section>
  </chapter>
  <node name="Input_002foutput" spaces=" ">
    <nodename>
      Input/output
    </nodename>
    <nodenext automatic="on">
      Command line interface
    </nodenext>
    <nodeprev automatic="on">
      Letters
    </nodeprev>
    <nodeup automatic="on">
      Top
    </nodeup>
  </node>
  <chapter spaces=" ">
    <sectiontitle>
      Input/output
    </sectiontitle>
    <cindex index="cp" spaces=" ">
      <indexterm index="cp" number="1209">
        input/output, to terminal
      </indexterm>
    </cindex>
    <cindex index="cp" spaces=" ">
      <indexterm index="cp" number="1210">
        terminal input/output
      </indexterm>
    </cindex>
    <cindex index="cp" spaces=" ">
      <indexterm index="cp" number="1211">
        input/output
      </indexterm>
    </cindex>
    <paraDefault handler: &latex;
>
       uses the ability to write to a file and later read it back in to build document components such as a table of contents or index. You can also read a file that other programs written, or write a file for others to read. You can communicate with users through the terminal. And, you can issue instructions for the operating system.
    </para>
    <menu endspaces=" ">
      <menuentry>
        <menuleadingtext>
          *
        </menuleadingtext>
        <menunode>
          \openin
          &
           \openout
        </menunode>
        <menuseparator>
          ::
        </menuseparator>
        <menudescription>
          <pre xml:space="preserve">
            Open a file.
          </pre>
        </menudescription>
      </menuentry>
      <menuentry>
        <menuleadingtext>
          *
        </menuleadingtext>
        <menunode>
          \read
        </menunode>
        <menuseparator>
          ::
        </menuseparator>
        <menudescription>
          <pre xml:space="preserve">
            Read text from a file.
          </pre>
        </menudescription>
      </menuentry>
      <menuentry>
        <menuleadingtext>
          *
        </menuleadingtext>
        <menunode>
          \typein
        </menunode>
        <menuseparator>
          ::
        </menuseparator>
        <menudescription>
          <pre xml:space="preserve">
            Read text from the terminal.
          </pre>
        </menudescription>
      </menuentry>
      <menuentry>
        <menuleadingtext>
          *
        </menuleadingtext>
        <menunode>
          \typeout
        </menunode>
        <menuseparator>
          ::
        </menuseparator>
        <menudescription>
          <pre xml:space="preserve">
            Write text to the terminal.
          </pre>
        </menudescription>
      </menuentry>
      <menuentry>
        <menuleadingtext>
          *
        </menuleadingtext>
        <menunode>
          \write
        </menunode>
        <menuseparator>
          ::
        </menuseparator>
        <menudescription>
          <pre xml:space="preserve">
            Write text to a file or terminal.
          </pre>
        </menudescription>
      </menuentry>
    </menu>
    <node name="_005copenin-_0026-_005copenout" spaces=" ">
      <nodename>
        \openin
        &
         \openout
      </nodename>
      <nodenext automatic="on">
        \read
      </nodenext>
      <nodeup automatic="on">
        Input/output
      </nodeup>
    </node>
    <section spaces=" ">
      <sectiontitle>
        <code>
          \openin
        </code>
        &
        <code>
          \openout
        </code>
      </sectiontitle>
      <anchor name="_005copenin">
        \openin
      </anchor>
      <anchor name="_005copenout">
        \openout
      </anchor>
      <anchor name="_005cclosein">
        \closein
      </anchor>
      <anchor name="_005ccloseout">
        \closeout
      </anchor>
      <findex index="fn" spaces=" ">
        <indexterm index="fn" number="1259" mergedindex="cp">
          \openin
        </indexterm>
      </findex>
      <findex index="fn" spaces=" ">
        <indexterm index="fn" number="1260" mergedindex="cp">
          \openout
        </indexterm>
      </findex>
      <findex index="fn" spaces=" ">
        <indexterm index="fn" number="1261" mergedindex="cp">
          \closein
        </indexterm>
      </findex>
      <findex index="fn" spaces=" ">
        <indexterm index="fn" number="1262" mergedindex="cp">
          \closeout
        </indexterm>
      </findex>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="1212">
          file, opening
        </indexterm>
      </cindex>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="1213">
          file, closing
        </indexterm>
      </cindex>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="1214">
          open a file
        </indexterm>
      </cindex>
      <para>
        Synopsis:
      </para>
      <example endspaces=" ">
        <pre xml:space="preserve">
          \openin
          <var>
            number
          </var>
          =
          <var>
            filename
          </var>
        </pre>
      </example>
      <para>
        or:
      </para>
      <example endspaces=" ">
        <pre xml:space="preserve">
          \openout
          <var>
            number
          </var>
          =
          <var>
            filename
          </var>
        </pre>
      </example>
      <para>
        Open a file for reading material, or for writing it. In most engines, the
        <var>
          number
        </var>
         must be between 0 and 15, as in
        <code>
          \openin3
        </code>
        ; in Lua
Default handler: &latex;
        ,
        <var>
          number
        </var>
         can be between 0 and 127.
      </para>
      <para>
        Here
Default handler: &tex;
         opens the file
        <file>
          presidents.tex
        </file>
         for reading.
      </para>
      <example endspaces=" ">
        <pre xml:space="preserve">
          \newread\presidentsfile \openin\presidentsfile=presidents \typeout
Default handler: &lbrace;
          presidentsfile is \the\presidentsfile
Default handler: &rbrace;
           \read\presidentsfile to\presidentline \typeout
Default handler: &lbrace;
          \presidentline
Default handler: &rbrace;
        </pre>
      </example>
      <noindent/>
      <para>
        The
        <code>
          \newread
        </code>
         command allocates input stream numbers from 0 to
Default handler: &nbsp;
        15 (there is also a
        <code>
          \newwrite
        </code>
        ). The
        <code>
          \presidentsfile
        </code>
         is more memorable but under the hood it is still a number; the first
        <code>
          \typeout
        </code>
         gives something like
        <samp>
          presidentsfile is 1
        </samp>
        . In addition,
        <code>
          \newread
        </code>
         keeps track of the allocation so that if you use too many then you get an error like
        <samp>
          ! No room for a new \read
        </samp>
        . The second
        <code>
          \typeout
        </code>
         gives the first line of the file, something like
        <samp>
          1 Washington, George
        </samp>
        .
      </para>
      <para>
        Ordinarily
Default handler: &tex;
         will not try to open the file until the next page shipout. To change this, use
        <code>
          \immediate\openin
          <var>
            number
          </var>
          =
          <var>
            filename
          </var>
        </code>
         or
        <code>
          \immediate\openout
          <var>
            number
          </var>
          =
          <var>
            filename
          </var>
        </code>
        .
      </para>
      <para>
        Close files with
        <code>
          \closein
          <var>
            number
          </var>
        </code>
         and
        <code>
          \closeout
          <var>
            number
          </var>
        </code>
        .
      </para>
      <para>
        How
Default handler: &latex;
         handles filenames varies among distributions, and even can vary among versions of a distribution. If the file does not have an extension then
Default handler: &tex;
         will add a
        <file>
          .tex
        </file>
        . This creates
        <file>
          presidents.tex
        </file>
        , writes one line to it, and closes it.
      </para>
      <example endspaces=" ">
        <pre xml:space="preserve">
          \newwrite\presidentsfile \openout\presidentsfile=presidents \write\presidentsfile
Default handler: &lbrace;
          1 Washington, George
Default handler: &rbrace;
           \closeout\presidentsfile
        </pre>
      </example>
      <noindent/>
      <para>
        But filenames with a period can cause trouble: if
Default handler: &tex;
         finds a
        <var>
          filename
        </var>
         of
        <file>
          presidents.dat
        </file>
         it could look first for
        <file>
          presidents.dat.tex
        </file>
         and later for
        <file>
          presidents.dat
        </file>
        , or it could do the opposite. Your distribution
Default handler: &textrsquo;
        s documentation should say more, and if you find something that works for you then you are good, but to ensure complete portability the best thing is to use file names containing only the twenty six ASCII letters (not case-sensitive) and the ten digits, along with underscore and dash, and in particular with no dot or space.
      </para>
      <para>
        For
        <code>
          \openin
        </code>
        , if
Default handler: &tex;
         cannot find the file then it does not give an error. It just considers that the stream is not open (test for this with
        <code>
          \ifeof
        </code>
        ; one recourse is the command
        <code>
          \InputIfFileExists
        </code>
        ,
        <pxref label="Class-and-package-commands">
          <xrefnodename>
            Class and package commands
          </xrefnodename>
        </pxref>
        ). If you try to use the same number twice,
Default handler: &latex;
         won
Default handler: &textrsquo;
        t give you an error. If you try to use a bad number then you get an error message like
        <samp>
          ! Bad number (16).
          <
          to be read again
          >
           = l.30 \openin16=test.jh
        </samp>
        .
      </para>
    </section>
    <node name="_005cread" spaces=" ">
      <nodename>
        \read
      </nodename>
      <nodenext automatic="on">
        \typein
      </nodenext>
      <nodeprev automatic="on">
        \openin
        &
         \openout
      </nodeprev>
      <nodeup automatic="on">
        Input/output
      </nodeup>
    </node>
    <section spaces=" ">
      <sectiontitle>
        <code>
          \read
        </code>
      </sectiontitle>
      <findex index="fn" spaces=" ">
        <indexterm index="fn" number="1263" mergedindex="cp">
          \read
        </indexterm>
      </findex>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="1215">
          file, reading
        </indexterm>
      </cindex>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="1216">
          read a file
        </indexterm>
      </cindex>
      <para>
        Synopsis:
      </para>
      <example endspaces=" ">
        <pre xml:space="preserve">
          \read
          <var>
            number
          </var>
           to
          <var>
            macro
          </var>
        </pre>
      </example>
      <para>
        Make the command
        <var>
          macro
        </var>
         contain the next line of input from text stream
        <var>
          number
        </var>
        , as in
        <code>
          \read5 to\data
        </code>
        .
      </para>
      <para>
        This opens the file
        <file>
          email.tex
        </file>
         for reading, puts the contents of the first line into the command
        <code>
          \email
        </code>
        , and then closes the file.
      </para>
      <example endspaces=" ">
        <pre xml:space="preserve">
          \newread\recipientfile \openin\recipientfile=email \read\recipientfile to\email \typeout
Default handler: &lbrace;
          Email address: \email
Default handler: &rbrace;
           \closein\recipientfile
        </pre>
      </example>
      <para>
        If
        <var>
          number
        </var>
         is outside the range from 0 to
Default handler: &nbsp;
        15 or if no file of that number is open, or if the file has ended, then
        <code>
          \read
        </code>
         will take input from the terminal (or exit if interaction is not allowed, e.g.,
        <code>
          \nonstopmode
        </code>
        ;
        <pxref label="interaction-modes">
          <xrefnodename>
            interaction modes
          </xrefnodename>
        </pxref>
        ). (However, the natural way in
Default handler: &latex;
         to take input from the terminal is
        <code>
          \typein
        </code>
         (
        <pxref label="_005ctypein">
          <xrefnodename>
            \typein
          </xrefnodename>
        </pxref>
        .)
      </para>
      <para>
        To read an entire file as additional
Default handler: &latex;
         source, use
        <code>
          \input
        </code>
         (
        <pxref label="_005cinput">
          <xrefnodename>
            \input
          </xrefnodename>
        </pxref>
        ) or
        <code>
          \include
        </code>
         (
        <pxref label="_005cinclude-_0026-_005cincludeonly">
          <xrefnodename>
            \include
            &
             \includeonly
          </xrefnodename>
        </pxref>
        ).
      </para>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="1217">
          <r>
            package
          </r>
          ,
          <code>
            datatool
          </code>
        </indexterm>
      </cindex>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="1218">
          <code>
            datatool
          </code>
          <r>
            package
          </r>
        </indexterm>
      </cindex>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="1219">
          mail merges
        </indexterm>
      </cindex>
      <para>
        A common reason to want to read from a data file is to do mail merges. CTAN has a number of packages for that; one is
        <code>
          datatool
        </code>
        .
      </para>
    </section>
    <node name="_005ctypein" spaces=" ">
      <nodename>
        \typein
      </nodename>
      <nodenext automatic="on">
        \typeout
      </nodenext>
      <nodeprev automatic="on">
        \read
      </nodeprev>
      <nodeup automatic="on">
        Input/output
      </nodeup>
    </node>
    <section spaces=" ">
      <sectiontitle>
        <code>
          \typein
        </code>
      </sectiontitle>
      <findex index="fn" spaces=" ">
        <indexterm index="fn" number="1264" mergedindex="cp">
          \typein
        </indexterm>
      </findex>
      <para>
        Synopsis, one of:
      </para>
      <example endspaces=" ">
        <pre xml:space="preserve">
          \typein
Default handler: &lbrace;
          <var>
            prompt-msg
          </var>
Default handler: &rbrace;
           \typein[
          <var>
            cmd
          </var>
          ]
Default handler: &lbrace;
          <var>
            prompt-msg
          </var>
Default handler: &rbrace;
        </pre>
      </example>
      <para>
        Print
        <var>
          prompt-msg
        </var>
         on the terminal and cause
Default handler: &latex;
         to stop and wait for you to type a line of input. This line of input ends when you hit the return key.
      </para>
      <para>
        For example, this
      </para>
      <example endspaces=" ">
        <pre xml:space="preserve">
          As long as I live I shall never forget \typein
Default handler: &lbrace;
          Enter student name:
Default handler: &rbrace;
        </pre>
      </example>
      <noindent/>
      <para>
        coupled with this command line interaction
      </para>
      <example endspaces=" ">
        <pre xml:space="preserve">
          Enter student name: \
Default handler: &arobase;
          typein=Aphra Behn
        </pre>
      </example>
      <noindent/>
      <para>
        gives the output
        <samp>
          ... never forget Aphra Behn
        </samp>
        .
      </para>
      <para>
        The first command version,
        <code>
          \typein
Default handler: &lbrace;
          <var>
            prompt-msg
          </var>
Default handler: &rbrace;
        </code>
        , causes the input you typed to be processed as if it had been included in the input file in place of the
        <code>
          \typein
        </code>
         command.
      </para>
      <para>
        In the second command version the optional argument
        <code>
          <var>
            cmd
          </var>
        </code>
         argument must be a command name, that is, it must begin with a backslash, \. This command name is then defined or redefined to be the input that you typed. For example, this
      </para>
      <example endspaces=" ">
        <pre xml:space="preserve">
          \typein[\student]
Default handler: &lbrace;
          Enter student name:
Default handler: &rbrace;
           \typeout
Default handler: &lbrace;
          Recommendation for \student .
Default handler: &rbrace;
        </pre>
      </example>
      <noindent/>
      <para>
        gives this output on the command line,
      </para>
      <example endspaces=" ">
        <pre xml:space="preserve">
          Enter student name: \student=John Dee Recommendation for John Dee.
        </pre>
      </example>
      <noindent/>
      <para>
        where the user has entered
        <samp>
          John Dee.
        </samp>
      </para>
    </section>
    <node name="_005ctypeout" spaces=" ">
      <nodename>
        \typeout
      </nodename>
      <nodenext automatic="on">
        \write
      </nodenext>
      <nodeprev automatic="on">
        \typein
      </nodeprev>
      <nodeup automatic="on">
        Input/output
      </nodeup>
    </node>
    <section spaces=" ">
      <sectiontitle>
        <code>
          \typeout
        </code>
      </sectiontitle>
      <findex index="fn" spaces=" ">
        <indexterm index="fn" number="1265" mergedindex="cp">
          \typeout
        </indexterm>
      </findex>
      <para>
        Synopsis:
      </para>
      <example endspaces=" ">
        <pre xml:space="preserve">
          \typeout
Default handler: &lbrace;
          <var>
            msg
          </var>
Default handler: &rbrace;
        </pre>
      </example>
      <para>
        Print
        <code>
          msg
        </code>
         on the terminal and in the
        <code>
          log
        </code>
         file.
      </para>
      <para>
        This
      </para>
      <example endspaces=" ">
        <pre xml:space="preserve">
          \newcommand
Default handler: &lbrace;
          \student
Default handler: &rbrace;
Default handler: &lbrace;
          John Dee
Default handler: &rbrace;
           \typeout
Default handler: &lbrace;
          Recommendation for \student .
Default handler: &rbrace;
        </pre>
      </example>
      <noindent/>
      <para>
        outputs
        <samp>
          Recommendation for John Dee
        </samp>
        . Like what happens here with
        <code>
          \student
        </code>
        , commands that are defined with
        <code>
          \newcommand
        </code>
         or
        <code>
          \renewcommand
        </code>
         (among others) are replaced by their definitions before being printed.
      </para>
      <findex index="fn" spaces=" ">
        <indexterm index="fn" number="1266" mergedindex="cp">
          \space
        </indexterm>
      </findex>
      <paraDefault handler: &latex;
Default handler: &textrsquo;
>
        s usual rules for treating multiple spaces as a single space and ignoring spaces after a command name apply to
        <code>
          msg
        </code>
        . Use the command
        <code>
          \space
        </code>
         to get a single space, independent of surrounding spaces. Use
        <code>
          ^^J
        </code>
         to get a newline. Get a percent character with
        <code>
          \csname
Default handler: &arobase;
          percentchar\endcsname
        </code>
        .
      </para>
      <para>
        This command can be useful for simple debugging, as here:
      </para>
      <example endspaces=" ">
        <pre xml:space="preserve">
          \newlength
Default handler: &lbrace;
          \jhlength
Default handler: &rbrace;
           \setlength
Default handler: &lbrace;
          \jhlength
Default handler: &rbrace;
Default handler: &lbrace;
          5pt
Default handler: &rbrace;
           \typeout
Default handler: &lbrace;
          The length is \the\jhlength.
Default handler: &rbrace;
        </pre>
      </example>
      <noindent/>
      <para>
        produces on the command line
        <samp>
          The length is 5.0pt
        </samp>
        .
      </para>
    </section>
    <node name="_005cwrite" spaces=" ">
      <nodename>
        \write
      </nodename>
      <nodeprev automatic="on">
        \typeout
      </nodeprev>
      <nodeup automatic="on">
        Input/output
      </nodeup>
    </node>
    <section spaces=" ">
      <sectiontitle>
        <code>
          \write
        </code>
      </sectiontitle>
      <findex index="fn" spaces=" ">
        <indexterm index="fn" number="1267" mergedindex="cp">
          \write
        </indexterm>
      </findex>
      <para>
        Synopsis:
      </para>
      <example endspaces=" ">
        <pre xml:space="preserve">
          \write
          <var>
            number
          </var>
Default handler: &lbrace;
          <var>
            string
          </var>
Default handler: &rbrace;
        </pre>
      </example>
      <para>
        Write
        <var>
          string
        </var>
         to the log file, to the terminal, or to a file opened by
        <code>
          \openout
        </code>
        . For instance,
        <code>
          \write6
        </code>
         writes to text stream number
Default handler: &nbsp;
        6.
      </para>
      <para>
        If the following appears in
        <file>
          <var>
            basefile
          </var>
          .tex
        </file>
         then it opens
        <file>
          <var>
            basefile
          </var>
          .jh
        </file>
        , writes
        <samp>
          Hello World!
        </samp>
         and a newline to it, and closes that file.
      </para>
      <example endspaces=" ">
        <pre xml:space="preserve">
          \newwrite\myfile \immediate\openout\myfile=\jobname.jh % \jobname is root file basename ... \immediate\write\myfile
Default handler: &lbrace;
          Hello world!
Default handler: &rbrace;
           ... \immediate\closeout\myfile
        </pre>
      </example>
      <findex index="fn" spaces=" ">
        <indexterm index="fn" number="1268" mergedindex="cp">
          \newwrite
        </indexterm>
      </findex>
      <noindent/>
      <para>
        The
        <code>
          \newwrite
        </code>
         allocates a stream number, giving it a symbolic name to make life easier, so that
        <code>
          stream \newwrite\myfile\the\myfile
        </code>
         produces something like
        <samp>
          stream 3
        </samp>
        . Then
        <code>
          \openout
        </code>
         associates the stream number with the given file name.
Default handler: &tex;
         ultimately executed
        <code>
          \write3
        </code>
         which puts the string in the file.
      </para>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="1220">
          log file, writing to
        </indexterm>
      </cindex>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="1221">
          terminal, writing to
        </indexterm>
      </cindex>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="1222">
          <math>
            -1
          </math>
          , write stream number
        </indexterm>
      </cindex>
      <para>
        Typically
        <var>
          number
        </var>
         is between 0 and
Default handler: &nbsp;
        15, because typically
Default handler: &latex;
         authors follow the prior example and the number is allocated by the system. If
        <var>
          number
        </var>
         is outside the range from 0 to 15 or if it is not associated with an open file then
Default handler: &latex;
         writes
        <var>
          string
        </var>
         to the log file. If
        <var>
          number
        </var>
         is positive then in addition
Default handler: &latex;
         writes
        <var>
          string
        </var>
         to the terminal.
      </para>
      <para>
        Thus,
        <code>
          test \write-1
Default handler: &lbrace;
          Hello World!
Default handler: &rbrace;
        </code>
         puts
        <samp>
          Hello World!
        </samp>
         followed by a newline in the log file. (This is what the
        <code>
          \wlog
        </code>
         command does;
        <pxref label="_005cwlog">
          <xrefnodename>
            \wlog
          </xrefnodename>
        </pxref>
        ). And
        <code>
          \write100
Default handler: &lbrace;
          Hello World!
Default handler: &rbrace;
        </code>
         puts the same in the log file but also puts
        <samp>
          Hello World!
        </samp>
         followed by a newline in the terminal output. (But 16, 17, and 18 are special as
        <var>
          number
        </var>
        ; see below.)
      </para>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="1223">
          Lua
Default handler: &tex;
          , 256 output streams in
        </indexterm>
      </cindex>
      <para>
        In Lua
Default handler: &tex;
        , instead of 16 output streams there are 256 (
        <pxref label="TeX-engines">
          <xrefnodenameDefault handler: &tex;
>
             engines
          </xrefnodename>
        </pxref>
        ).
      </para>
      <findex index="fn" spaces=" ">
        <indexterm index="fn" number="1269" mergedindex="cp">
          \
Default handler: &arobase;
          auxout
        </indexterm>
      </findex>
      <findex index="fn" spaces=" ">
        <indexterm index="fn" number="1270" mergedindex="cp">
          \
Default handler: &arobase;
          mainaux
        </indexterm>
      </findex>
      <para>
        Use
        <code>
          \write\
Default handler: &arobase;
          auxout
Default handler: &lbrace;
          <var>
            string
          </var>
Default handler: &rbrace;
        </code>
         to write to the current
        <file>
          .aux
        </file>
         file, which is associated with either the root file or with the current include file; and use
        <code>
          \write\
Default handler: &arobase;
          mainaux
Default handler: &lbrace;
          <var>
            string
          </var>
Default handler: &rbrace;
        </code>
         to write to the main
        <file>
          .aux
        </file>
        . These symbolic names are defined by
Default handler: &latex;
        .
      </para>
Default handler: <!-- c credit: David Carlisle https://tex.stackexchange.com/a/115933/121234 -->
      <para>
        By default
Default handler: &latex;
         does not write
        <var>
          string
        </var>
         to the file right away. This is because, for example, you may need
        <code>
          \write
        </code>
         to save the current page number, but when
Default handler: &tex;
         comes across a
        <code>
          \write
        </code>
         it typically does not know what the page number is, since it has not yet done the page breaking. So, you use
        <code>
          \write
        </code>
         in one of three contexts:
      </para>
      <example endspaces=" ">
        <pre xml:space="preserve">
          \immediate\write\
Default handler: &arobase;
          auxout
Default handler: &lbrace;
          <var>
            string
          </var>
Default handler: &rbrace;
           %1 \write\
Default handler: &arobase;
          auxout
Default handler: &lbrace;
          <var>
            string
          </var>
Default handler: &rbrace;
           %2 \protected
Default handler: &arobase;
          write\
Default handler: &arobase;
          auxout
Default handler: &lbrace;
Default handler: &rbrace;
Default handler: &lbrace;
          <var>
            string
          </var>
Default handler: &rbrace;
           %3
        </pre>
      </example>
      <enumerate first="1" endspaces=" ">
        <listitem>
          <cindex index="cp" spaces=" ">
            <indexterm index="cp" number="1224">
              immediate
              <code>
                \write
              </code>
            </indexterm>
          </cindex>
          <findex index="fn" spaces=" ">
            <indexterm index="fn" number="1271" mergedindex="cp">
              \immediate\write
            </indexterm>
          </findex>
          <para>
            With the first,
Default handler: &latex;
             writes
            <var>
              string
            </var>
             to the file immediately. Any macros in
            <var>
              string
            </var>
             are fully expanded (just as in
            <code>
              \edef
            </code>
            ) so to prevent expansion you must use
            <code>
              \noexpand
            </code>
            ,
            <code>
              toks
            </code>
            , etc., except that you should use
            <code>
              #
            </code>
             instead of
            <code>
              ##
            </code>
            ).
          </para>
        </listitem>
        <listitem>
          <cindex index="cp" spaces=" ">
            <indexterm index="cp" number="1225">
              delayed
              <code>
                \write
              </code>
            </indexterm>
          </cindex>
          <cindex index="cp" spaces=" ">
            <indexterm index="cp" number="1226">
              whatsit item
            </indexterm>
          </cindex>
          <findex index="fn" spaces=" ">
            <indexterm index="fn" number="1272" mergedindex="cp">
              \shipout
              <r>
                and expansion
              </r>
            </indexterm>
          </findex>
          <para>
            With the second,
            <var>
              string
            </var>
             is stored on the current list of things (as a
Default handler: &tex;
Default handler: &textldquo;
            whatsit
Default handler: &textrdquo;
             item) and kept until the page is shipped out and likewise the macros are unexpanded until
            <code>
              \shipout
            </code>
            . At
            <code>
              \shipout
            </code>
            ,
            <var>
              string
            </var>
             is fully expanded.
          </para>
        </listitem>
        <listitem>
          <findex index="fn" spaces=" ">
            <indexterm index="fn" number="1273" mergedindex="cp">
              \protected
Default handler: &arobase;
              write
            </indexterm>
          </findex>
          <para>
            The third,
            <code>
              \protected
Default handler: &arobase;
              write
            </code>
            , is like the second except that you can use
            <code>
              \protect
            </code>
             to avoid expansion. The extra first argument allows you to locally insert extra definitions to make more macros protected or to have some other special definition for the write.
          </para>
        </listitem>
      </enumerate>
      <para>
        As a simple example of expansion with
        <code>
          \write
        </code>
        ,
        <var>
          string
        </var>
         here contains a control sequence
        <code>
          \triplex
        </code>
         which we
Default handler: &textrsquo;
        ve defined to be the text
        <samp>
          XYZ
        </samp>
        :
      </para>
      <example endspaces=" ">
        <pre xml:space="preserve">
          \newwrite\jhfile \openout\jhfile=test.jh \newcommand
Default handler: &lbrace;
          \triplex
Default handler: &rbrace;
Default handler: &lbrace;
          XYZ
Default handler: &rbrace;
           \write\jhfile
Default handler: &lbrace;
          test \triplex test
Default handler: &rbrace;
        </pre>
      </example>
      <noindent/>
      <para>
        This results in the file
        <file>
          test.jh
        </file>
         containing the text
        <samp>
          test XYZtest
        </samp>
         followed by a newline.
      </para>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="1227">
          <code>
            \write
          </code>
           streams 16, 17, 18
        </indexterm>
      </cindex>
      <para>
        The cases where
        <var>
          number
        </var>
         is 16, 17, or 18 are special. Because of
        <code>
          \write
        </code>
Default handler: &textrsquo;
        s behavior when
        <var>
          number
        </var>
         is outside the range from 0 to 15 described above, in Plain
Default handler: &nbsp;
Default handler: &tex;
        <code>
          \write16
        </code>
         and
        <code>
          \write17
        </code>
         were sometimes used to write to the log file and the terminal; however, in
Default handler: &latex;
        , the natural way to do that is with
        <code>
          \typeout
        </code>
         (
        <pxref label="_005ctypeout">
          <xrefnodename>
            \typeout
          </xrefnodename>
        </pxref>
        ). The
        <code>
          \write18
        </code>
         command is even more special; modern
Default handler: &tex;
         systems use it for giving commands to the operating system (
        <pxref label="_005cwrite18">
          <xrefnodename>
            \write18
          </xrefnodename>
        </pxref>
        ).
      </para>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="1228">
          newline, in
          <code>
            \write
          </code>
        </indexterm>
      </cindex>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="1229">
          <code>
            ^^J
          </code>
          , in
          <code>
            \write
          </code>
        </indexterm>
      </cindex>
      <para>
        Ordinarily
        <code>
          \write
        </code>
         outputs a single line. You can include a newline with
        <code>
          ^^J
        </code>
        . Thus, this produces two lines in the log file:
      </para>
      <example endspaces=" ">
        <pre xml:space="preserve">
          \wlog
Default handler: &lbrace;
          Parallel lines have a lot in common.^^JBut they never meet.
Default handler: &rbrace;
        </pre>
      </example>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="1230">
          <r>
            package
          </r>
          ,
          <code>
            answers
          </code>
        </indexterm>
      </cindex>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="1231">
          <code>
            answers
          </code>
          <r>
            package
          </r>
        </indexterm>
      </cindex>
      <para>
        A common case where authors need to write their own file is for answers to exercises, or another situation where you want to write out verbatim, without expanding the macros. CTAN has a number of packages for this; one is
        <code>
          answers
        </code>
        .
      </para>
      <menu endspaces=" ">
        <menuentry>
          <menuleadingtext>
            *
          </menuleadingtext>
          <menunode>
            \write and security
          </menunode>
          <menuseparator>
            ::
          </menuseparator>
          <menudescription>
            <pre xml:space="preserve">
              Security.
            </pre>
          </menudescription>
        </menuentry>
        <menuentry>
          <menuleadingtext>
            *
          </menuleadingtext>
          <menunode>
            \message
          </menunode>
          <menuseparator>
            ::
          </menuseparator>
          <menudescription>
            <pre xml:space="preserve">
              Write text to the log file and terminal.
            </pre>
          </menudescription>
        </menuentry>
        <menuentry>
          <menuleadingtext>
            *
          </menuleadingtext>
          <menunode>
            \wlog
          </menunode>
          <menuseparator>
            ::
          </menuseparator>
          <menudescription>
            <pre xml:space="preserve">
              Write text to the log file.
            </pre>
          </menudescription>
        </menuentry>
        <menuentry>
          <menuleadingtext>
            *
          </menuleadingtext>
          <menunode>
            \write18
          </menunode>
          <menuseparator>
            ::
          </menuseparator>
          <menudescription>
            <pre xml:space="preserve">
              Run an operating system command.
            </pre>
          </menudescription>
        </menuentry>
      </menu>
      <node name="_005cwrite-and-security" spaces=" ">
        <nodename>
          \write and security
        </nodename>
        <nodenext automatic="on">
          \message
        </nodenext>
        <nodeup automatic="on">
          \write
        </nodeup>
      </node>
      <subsection spaces=" ">
        <sectiontitle>
          <code>
            \write
          </code>
           and security
        </sectiontitle>
        <cindex index="cp" spaces=" ">
          <indexterm index="cp" number="1232">
            security and
            <code>
              \write
            </code>
          </indexterm>
        </cindex>
        <cindex index="cp" spaces=" ">
          <indexterm index="cp" number="1233">
            <code>
              \write
            </code>
             and security
          </indexterm>
        </cindex>
        <para>
          The ability to write files raises security issues. If you compiled a downloaded
Default handler: &latex;
           file and it overwrote your password file then you would be justifiably troubled.
        </para>
        <para>
          Thus, by default
Default handler: &tex;
           systems only allow you to open files for writing that are in the current directory or output directory, if specified (
          <pxref label="output-directory">
            <xrefnodename>
              output directory
            </xrefnodename>
          </pxref>
          ), or in a subdirectory of those. So, this code
        </para>
        <example endspaces=" ">
          <pre xml:space="preserve">
            \newwrite\jhfile \openout\jhfile=../test.jh
          </pre>
        </example>
        <noindent/>
        <para>
          gives an error like:
        </para>
        <example endspaces=" ">
          <pre xml:space="preserve">
            Not writing to ../test.jh (openout_any = p). ! I can't write on file `../test.jh'
          </pre>
        </example>
        <cindex index="cp" spaces=" ">
          <indexterm index="cp" number="1234">
            parent directories, cannot write to
          </indexterm>
        </cindex>
        <para>
          You can get just such an error when using commands such as
          <code>
            \include
Default handler: &lbrace;
            ../filename
Default handler: &rbrace;
          </code>
           because
Default handler: &latex;
           will try to open
          <file>
            ../filename.aux
          </file>
          . The simplest solution is to put the included files in the same directory as the root file, or in subdirectories.
        </para>
      </subsection>
      <node name="_005cmessage" spaces=" ">
        <nodename>
          \message
        </nodename>
        <nodenext automatic="on">
          \wlog
        </nodenext>
        <nodeprev automatic="on">
          \write and security
        </nodeprev>
        <nodeup automatic="on">
          \write
        </nodeup>
      </node>
      <subsection spaces=" ">
        <sectiontitle>
          <code>
            \message
          </code>
        </sectiontitle>
        <findex index="fn" spaces=" ">
          <indexterm index="fn" number="1274" mergedindex="cp">
            \message
          </indexterm>
        </findex>
        <para>
          Synopsis:
        </para>
        <example endspaces=" ">
          <pre xml:space="preserve">
            \message
Default handler: &lbrace;
            <var>
              string
            </var>
Default handler: &rbrace;
          </pre>
        </example>
        <para>
          Write
          <var>
            string
          </var>
           to the log file and the terminal.
        </para>
        <para>
          Typically,
Default handler: &latex;
           authors use
          <code>
            \typeout
          </code>
           (
          <pxref label="_005ctypeout">
            <xrefnodename>
              \typeout
            </xrefnodename>
          </pxref>
          ). It allows you to use
          <code>
            \protect
          </code>
           on any fragile commands in
          <var>
            string
          </var>
           (
          <pxref label="_005cprotect">
            <xrefnodename>
              \protect
            </xrefnodename>
          </pxref>
          ). But
          <code>
            \typeout
          </code>
           always inserts a newline at the end of
          <var>
            string
          </var>
           while
          <code>
            \message
          </code>
           does not, so the latter can be useful.
        </para>
        <para>
          With this example document body.
        </para>
        <example endspaces=" ">
          <pre xml:space="preserve">
            before\message
Default handler: &lbrace;
            One Two
Default handler: &rbrace;
            \message
Default handler: &lbrace;
            Three
Default handler: &rbrace;
            \message
Default handler: &lbrace;
            Four^^JI
Default handler: &rbrace;
             \message
Default handler: &lbrace;
            declare a thumb war.
Default handler: &rbrace;
            After
          </pre>
        </example>
        <noindent/>
        <para>
          under some circumstances (see below)
Default handler: &latex;
           writes the following to both the terminal and the log file.
        </para>
        <example endspaces=" ">
          <pre xml:space="preserve">
            One Two Three Four I declare a thumb war.
          </pre>
        </example>
        <noindent/>
        <para>
          The
          <code>
            ^^J
          </code>
           produces a newline. Also, in the output document, between
          <samp>
            before
          </samp>
           and
          <samp>
            After
          </samp>
           will be a single space (from the end of line following
          <samp>
            I
Default handler: &rbrace;
          </samp>
          ).
        </para>
        <para>
          While
          <code>
            \message
          </code>
           allows you more control over formatting, a gotcha is that
Default handler: &latex;
           may mess up that formatting because it inserts line breaks depending on what it has already written. Contrast this document body, where the
          <samp>
            Two
          </samp>
           has moved, to the one given above.
        </para>
        <example endspaces=" ">
          <pre xml:space="preserve">
            before\message
Default handler: &lbrace;
            One
Default handler: &rbrace;
            \message
Default handler: &lbrace;
            Two Three
Default handler: &rbrace;
            \message
Default handler: &lbrace;
            Four^^JI
Default handler: &rbrace;
             \message
Default handler: &lbrace;
            declare a thumb war.
Default handler: &rbrace;
            After
          </pre>
        </example>
        <para>
          This can happen: when
Default handler: &latex;
           is outputting the messages to the terminal, now the message with
          <samp>
            One
          </samp>
           is shorter and it fits at the end of the output terminal line, and so
Default handler: &latex;
           breaks the line between it and the
          <samp>
            Two Three
          </samp>
          . That line break appears also in the log file. This line break insertion can depend on, for instance, the length of the full path names of included files. So producing finely-formatted lines in a way that is portable is hard, likely requiring starting your message at the beginning of a line.
        </para>
      </subsection>
      <node name="_005cwlog" spaces=" ">
        <nodename>
          \wlog
        </nodename>
        <nodenext automatic="on">
          \write18
        </nodenext>
        <nodeprev automatic="on">
          \message
        </nodeprev>
        <nodeup automatic="on">
          \write
        </nodeup>
      </node>
      <subsection spaces=" ">
        <sectiontitle>
          <code>
            \wlog
          </code>
        </sectiontitle>
        <findex index="fn" spaces=" ">
          <indexterm index="fn" number="1275" mergedindex="cp">
            \wlog
          </indexterm>
        </findex>
        <para>
          Synopsis:
        </para>
        <example endspaces=" ">
          <pre xml:space="preserve">
            \wlog
Default handler: &lbrace;
            <var>
              string
            </var>
Default handler: &rbrace;
          </pre>
        </example>
        <para>
          Write
          <var>
            string
          </var>
           to the log file.
        </para>
        <example endspaces=" ">
          <pre xml:space="preserve">
            \wlog
Default handler: &lbrace;
            Did you hear about the mathematician who hates negatives?
Default handler: &rbrace;
             \wlog
Default handler: &lbrace;
            He'll stop at nothing to avoid them.
Default handler: &rbrace;
          </pre>
        </example>
        <para>
          Ordinarily
          <var>
            string
          </var>
           appears in a single separate line. Use
          <code>
            ^^J
          </code>
           to insert a newline.
        </para>
        <example endspaces=" ">
          <pre xml:space="preserve">
            \wlog
Default handler: &lbrace;
            Helvetica and Times Roman walk into a bar.
Default handler: &rbrace;
             \wlog
Default handler: &lbrace;
            The barman says,^^JWe don't serve your type.
Default handler: &rbrace;
          </pre>
        </example>
      </subsection>
      <node name="_005cwrite18" spaces=" ">
        <nodename>
          \write18
        </nodename>
        <nodeprev automatic="on">
          \wlog
        </nodeprev>
        <nodeup automatic="on">
          \write
        </nodeup>
      </node>
      <subsection spaces=" ">
        <sectiontitle>
          <code>
            \write18
          </code>
        </sectiontitle>
        <findex index="fn" spaces=" ">
          <indexterm index="fn" number="1276" mergedindex="cp">
            \write18
          </indexterm>
        </findex>
        <cindex index="cp" spaces=" ">
          <indexterm index="cp" number="1235">
            external commands
          </indexterm>
        </cindex>
        <cindex index="cp" spaces=" ">
          <indexterm index="cp" number="1236">
            commands, run from
Default handler: &latex;
          </indexterm>
        </cindex>
        <cindex index="cp" spaces=" ">
          <indexterm index="cp" number="1237">
            system commands, run from
Default handler: &latex;
          </indexterm>
        </cindex>
        <cindex index="cp" spaces=" ">
          <indexterm index="cp" number="1238">
            shell access
          </indexterm>
        </cindex>
Default handler: <!-- c Derived from: Joseph Wright: https://tex.stackexchange.com/a/20446/121234 -->
        <para>
          Synopsis:
        </para>
        <example endspaces=" ">
          <pre xml:space="preserve">
            \write18
Default handler: &lbrace;
            <var>
              shell_command
            </var>
Default handler: &rbrace;
          </pre>
        </example>
        <para>
          Issue a command to the operating system shell. The operating system runs the command and
Default handler: &latex;
Default handler: &textrsquo;
          s execution is blocked until that finishes.
        </para>
        <cindex index="cp" spaces=" ">
          <indexterm index="cp" number="1239">
            <r>
              package
            </r>
            ,
            <code>
              Asymptote
            </code>
          </indexterm>
        </cindex>
        <cindex index="cp" spaces=" ">
          <indexterm index="cp" number="1240">
            <code>
              Asymptote
            </code>
            <r>
              package
            </r>
          </indexterm>
        </cindex>
        <para>
          This sequence (on Unix)
        </para>
        <example endspaces=" ">
          <pre xml:space="preserve">
            \usepackage
Default handler: &lbrace;
            graphicx
Default handler: &rbrace;
             % in preamble ... \newcommand
Default handler: &lbrace;
            \fignum
Default handler: &rbrace;
Default handler: &lbrace;
            1
Default handler: &rbrace;
             \immediate\write18
Default handler: &lbrace;
            cd pix
            &
            &
             asy figure\fignum
Default handler: &rbrace;
             \includegraphics
Default handler: &lbrace;
            pix/figure\fignum.pdf
Default handler: &rbrace;
          </pre>
        </example>
        <noindent/>
        <para>
          will run Asymptote (the
          <code>
            asy
          </code>
           program) on
          <file>
            pix/figure1.asy
          </file>
          , so that the document can later read in the resulting graphic (
          <pxref label="_005cincludegraphics">
            <xrefnodename>
              \includegraphics
            </xrefnodename>
          </pxref>
          ). Like any
          <code>
            \write
          </code>
          , here
Default handler: &latex;
           expands macros in
          <var>
            shell_command
          </var>
           so that
          <code>
            \fignum
          </code>
           is replaced by
          <samp>
            1
          </samp>
          .
        </para>
        <para>
          Another example is that you can automatically run Bib
Default handler: &tex;
           at the start of each
Default handler: &latex;
           run (
          <pxref label="Using-BibTeX">
            <xrefnodename>
              Using BibTeX
            </xrefnodename>
          </pxref>
          ) by including
          <code>
            \immediate\write18
Default handler: &lbrace;
            bibtex8 \jobname
Default handler: &rbrace;
          </code>
           as the first line of the file. Note that
          <code>
            \jobname
          </code>
           expands to the basename of the root file unless the
          <code>
            --jobname
          </code>
           option is passed on the command line, in which case this is the option argument.
        </para>
        <para>
          You sometimes need to do a multi-step process to get the information that you want. This will insert into the input a list of all PDF files in the current directory (but see
          <code>
            texosquery
          </code>
           below):
        </para>
        <example endspaces=" ">
          <pre xml:space="preserve">
            \immediate\write18
Default handler: &lbrace;
            ls *.pdf
            >
             tmp.dat
Default handler: &rbrace;
             \input
Default handler: &lbrace;
            tmp.dat
Default handler: &rbrace;
          </pre>
        </example>
        <para>
          The standard behavior of any
          <code>
            \write
          </code>
           is to wait until a page is being shipped out before expanding the macros or writing to the stream (
          <pxref label="_005cwrite">
            <xrefnodename>
              \write
            </xrefnodename>
          </pxref>
          ). But sometimes you want it done now. For this, use
          <code>
            \immediate\write18
Default handler: &lbrace;
            <var>
              shell_command
            </var>
Default handler: &rbrace;
          </code>
          .
        </para>
        <para>
          There are obvious security issues with allowing system commands inside a
Default handler: &latex;
           file. If you download a file off the net and it contains commands to delete all your files then you would be unhappy. The standard settings in modern distributions turn off full shell access. You can turn it on, if you are sure the shell commands are safe, by compiling with
          <code>
            latex --enable-write18
            <var>
              filename
            </var>
          </code>
           (
          <pxref label="Command-line-options">
            <xrefnodename>
              Command line options
            </xrefnodename>
          </pxref>
          ). (The
          <code>
            --shell-escape
          </code>
           option is a synonym, in
Default handler: &tex;
           Live.)
        </para>
        <cindex index="cp" spaces=" ">
          <indexterm index="cp" number="1241">
            restricted shell access
          </indexterm>
        </cindex>
        <para>
          In the place of full shell access, modern distributions by default use a restricted version that allows some commands to work, such as those that run Metafont to generate missing fonts, even if you do not use the
          <code>
            enable-write18
          </code>
           option. By default this list of allowed commands is short and features only commands that are under the control of the distribution maintainers (
          <pxref label="Command-line-options">
            <xrefnodename>
              Command line options
            </xrefnodename>
          </pxref>
          ).
        </para>
        <findex index="fn" spaces=" ">
          <indexterm index="fn" number="1277" mergedindex="cp">
            /bin/sh
            <r>
              , used by
              <code>
                \write18
              </code>
            </r>
          </indexterm>
        </findex>
        <findex index="fn" spaces=" ">
          <indexterm index="fn" number="1278" mergedindex="cp">
            sh
            <r>
              , used by
              <code>
                \write18
              </code>
            </r>
          </indexterm>
        </findex>
        <findex index="fn" spaces=" ">
          <indexterm index="fn" number="1279" mergedindex="cp">
            cmd.exe
            <r>
              , used by
              <code>
                \write18
              </code>
            </r>
          </indexterm>
        </findex>
        <findex index="fn" spaces=" ">
          <indexterm index="fn" number="1280" mergedindex="cp">
            SHELL
            <r>
              , environment variables
            </r>
          </indexterm>
        </findex>
        <para>
          The
          <var>
            shell_command
          </var>
           text is always passed to
          <file>
            /bin/sh
          </file>
           on Unix-like operating systems, and the DOS command interpreter
          <file>
            cmd.exe
          </file>
           on Windows. Any different shell set by the user, and the
          <code>
            SHELL
          </code>
           environment variable, is ignored.
        </para>
        <cindex index="cp" spaces=" ">
          <indexterm index="cp" number="1242">
            <r>
              package
            </r>
            ,
            <code>
              texosquery
            </code>
          </indexterm>
        </cindex>
        <cindex index="cp" spaces=" ">
          <indexterm index="cp" number="1243">
            <code>
              texosquery
            </code>
            <r>
              package
            </r>
          </indexterm>
        </cindex>
        <cindex index="cp" spaces=" ">
          <indexterm index="cp" number="1244">
            system information
          </indexterm>
        </cindex>
        <cindex index="cp" spaces=" ">
          <indexterm index="cp" number="1245">
            operating system information
          </indexterm>
        </cindex>
        <cindex index="cp" spaces=" ">
          <indexterm index="cp" number="1246">
            locale information, from system
          </indexterm>
        </cindex>
        <cindex index="cp" spaces=" ">
          <indexterm index="cp" number="1247">
            directory listings, from system
          </indexterm>
        </cindex>
        <para>
          If what you need is system information, such as the operating system name, locale information, or directory contents, take a look at the
          <code>
            texosquery
          </code>
           package, which provides a convenient and secure interface for this, unlike the above examples using the raw
          <code>
            \write18
          </code>
          :
          <url>
            <urefurl>
              https://ctan.org/pkg/texosquery
            </urefurl>
          </url>
          .
        </para>
        <cindex index="cp" spaces=" ">
          <indexterm index="cp" number="1248">
            <r>
              package
            </r>
            ,
            <code>
              shellesc
            </code>
          </indexterm>
        </cindex>
        <cindex index="cp" spaces=" ">
          <indexterm index="cp" number="1249">
            <code>
              shellesc
            </code>
            <r>
              package
            </r>
          </indexterm>
        </cindex>
        <findex index="fn" spaces=" ">
          <indexterm index="fn" number="1281" mergedindex="cp">
            \ShellEscape
          </indexterm>
        </findex>
        <findex index="fn" spaces=" ">
          <indexterm index="fn" number="1282" mergedindex="cp">
            \DelayedShellEscape
          </indexterm>
        </findex>
        <paraDefault handler: &latex;
>
           provides a package
          <code>
            shellesc
          </code>
           on top of the primitive
          <code>
            \write18
          </code>
           command. Its primary purpose is to provide a command
          <code>
            \ShellEscape
          </code>
           which works identically on all
Default handler: &tex;
           engines; Lua
Default handler: &tex;
           intentionally did not retain
          <code>
            \write18
          </code>
           as a way to invoke a shell command, so some engine-specific code is needed. The
          <code>
            shellesc
          </code>
           package also provides a command
          <code>
            \DelayedShellEscape
          </code>
          , executed at
          <code>
            \output
          </code>
           time, for the same reason.
        </para>
      </subsection>
    </section>
  </chapter>
  <node name="Command-line-interface" spaces=" ">
    <nodename>
      Command line interface
    </nodename>
    <nodenext automatic="on">
      Document templates
    </nodenext>
    <nodeprev automatic="on">
      Input/output
    </nodeprev>
    <nodeup automatic="on">
      Top
    </nodeup>
  </node>
  <chapter spaces=" ">
    <sectiontitle>
      Command line interface
    </sectiontitle>
    <anchor name="Command-line">
      Command line
    </anchor>
Default handler: <!-- c old name -->
    <cindex index="cp" spaces=" ">
      <indexterm index="cp" number="1250">
        command line interface
      </indexterm>
    </cindex>
    <cindex index="cp" spaces=" ">
      <indexterm index="cp" number="1251">
        interface, command line
      </indexterm>
    </cindex>
    <cindex index="cp" spaces=" ">
      <indexterm index="cp" number="1252">
        CLI
      </indexterm>
    </cindex>
    <para>
      Synopsis (from a terminal command line):
    </para>
    <example endspaces=" ">
      <pre xml:space="preserve">
        pdflatex
        <var>
          options
        </var>
        <var>
          argument
        </var>
      </pre>
    </example>
    <para>
      Run
Default handler: &latex;
       on
      <var>
        argument
      </var>
      . In place of
      <command>
        pdflatex
      </command>
       you can also use (for PDF output)
      <command>
        xelatex
      </command>
       or
      <code>
        lualatex
      </code>
      , or (for DVI output)
      <code>
        latex
      </code>
       or
      <code>
        dvilualatex
      </code>
      , among others (
      <pxref label="TeX-engines">
        <xrefnodenameDefault handler: &tex;
>
           engines
        </xrefnodename>
      </pxref>
      ).
    </para>
    <para>
      For example, this will run
Default handler: &latex;
       on the file
      <file>
        thesis.tex
      </file>
      , creating the output
      <file>
        thesis.pdf
      </file>
      .
    </para>
    <example endspaces=" ">
      <pre xml:space="preserve">
        pdflatex thesis
      </pre>
    </example>
    <noindent/>
    <findex index="fn" spaces=" ">
      <indexterm index="fn" number="1283" mergedindex="cp">
        .tex,
        <r>
          default extension
        </r>
      </indexterm>
    </findex>
    <para>
      Note that
      <file>
        .tex
      </file>
       is the default file name extension.
    </para>
    <para>
      pdf
Default handler: &tex;
       is an extension of the original
Default handler: &tex;
       program, as are Xe
Default handler: &tex;
       and Lua
Default handler: &tex;
       (
      <pxref label="TeX-engines">
        <xrefnodenameDefault handler: &tex;
>
           engines
        </xrefnodename>
      </pxref>
      ). The first two are completely backward compatible and the latter, almost so. Perhaps the most fundamental new feature for all three is that the original
Default handler: &tex;
       output its own DVI format, while the newer ones can output directly to PDF. This allows them to take advantage of the extra features in PDF such as hyperlinks, support for modern image formats such as JPG and PNG, and ubiquitous viewing programs. In short, if you run
      <command>
        pdflatex
      </command>
       or
      <command>
        xelatex
      </command>
       or
      <command>
        lualatex
      </command>
       then you will by default get PDF and have access to all its modern features. If you run
      <command>
        latex
      </command>
      , or
      <command>
        dvilualatex
      </command>
      , then you will get DVI. The description here assumes
      <command>
        pdflatex
      </command>
      .
    </para>
    <para>
      <xref label="Command-line-options">
        <xrefnodename>
          Command line options
        </xrefnodename>
      </xref>
      , for a selection of the most useful command line options. As to
      <var>
        argument
      </var>
      , the usual case is that it does not begin with a backslash, so the system takes it to be the name of a file and it compiles that file. If
      <var>
        argument
      </var>
       begins with a backslash then the system will interpret it as a line of
Default handler: &latex;
       input, which can be used for special effects (
      <pxref label="Command-line-input">
        <xrefnodename>
          Command line input
        </xrefnodename>
      </pxref>
      ).
    </para>
    <para>
      If you gave no arguments or options then
      <command>
        pdflatex
      </command>
       prompts for input from the terminal. You can escape from this by entering
      <kbd>
        CTRL-D
      </kbd>
      .
    </para>
    <para>
      If
Default handler: &latex;
       finds an error in your document then by default it stops and asks you about it.
      <xref label="Recovering-from-errors">
        <xrefnodename>
          Recovering from errors
        </xrefnodename>
      </xref>
      , for an outline of what to do.
    </para>
    <menu endspaces=" ">
      <menuentry>
        <menuleadingtext>
          *
        </menuleadingtext>
        <menunode>
          Command line options
        </menunode>
        <menuseparator>
          ::
        </menuseparator>
        <menudescription>
          <pre xml:space="preserve">
            Commonly used command line options.
          </pre>
        </menudescription>
      </menuentry>
      <menuentry>
        <menuleadingtext>
          *
        </menuleadingtext>
        <menunode>
          Command line input
        </menunode>
        <menuseparator>
          ::
        </menuseparator>
        <menudescription>
          <pre xml:space="preserve">
            Specify LaTeX code on the command line.
          </pre>
        </menudescription>
      </menuentry>
      <menuentry>
        <menuleadingtext>
          *
        </menuleadingtext>
        <menunode>
          Jobname
        </menunode>
        <menuseparator>
          ::
        </menuseparator>
        <menudescription>
          <pre xml:space="preserve">
            How
Default handler: &tex;
             sets the current job name.
          </pre>
        </menudescription>
      </menuentry>
      <menuentry>
        <menuleadingtext>
          *
        </menuleadingtext>
        <menunode>
          Recovering from errors
        </menunode>
        <menuseparator>
          ::
        </menuseparator>
        <menudescription>
          <pre xml:space="preserve">
            When something goes wrong.
          </pre>
        </menudescription>
      </menuentry>
    </menu>
    <node name="Command-line-options" spaces=" ">
      <nodename>
        Command line options
      </nodename>
      <nodenext automatic="on">
        Command line input
      </nodenext>
      <nodeup automatic="on">
        Command line interface
      </nodeup>
    </node>
    <section spaces=" ">
      <sectiontitle>
        Command line options
      </sectiontitle>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="1253">
          options, command line
        </indexterm>
      </cindex>
      <para>
        These are the command-line options relevant to ordinary document authoring. For a full list, try running
        <samp>
          latex --help
        </samp>
         from the command line.
      </para>
      <para>
        With many implementations you can specify command line options by prefixing them with
        <samp>
          -
        </samp>
         or
        <samp>
          --
        </samp>
        . This is the case for both
Default handler: &tex;
         Live (including Mac
Default handler: &tex;
        ) and MiK
Default handler: &tex;
        . We will use both conventions interchangeably. If an option takes a value, it can be specified either as a separate argument (
        <samp>
          --foo val
        </samp>
        ), or as one argument with an
        <samp>
          =
        </samp>
         sign (
        <samp>
          --foo=val
        </samp>
        ), but there can be no spaces around the
        <samp>
          =
        </samp>
        . We will generally use the
        <samp>
          =
        </samp>
         syntax.
      </para>
      <table commandarg="code" spaces=" " endspaces=" ">
        <tableentry>
          <tableterm>
            <findex index="fn" spaces=" ">
              <indexterm index="fn" number="1284" mergedindex="cp">
                --version
                <r>
                  command-line option
                </r>
              </indexterm>
            </findex>
            <item spaces=" ">
              <itemformat command="code">
                -version
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <para>
              Show the current version, like
              <samp>
                pdfTeX 3.14159265-2.6-1.40.16 (TeX Live 2015/Debian)
              </samp>
               along with a small amount of additional information, and exit.
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <findex index="fn" spaces=" ">
              <indexterm index="fn" number="1285" mergedindex="cp">
                --help
                <r>
                  command-line option
                </r>
              </indexterm>
            </findex>
            <item spaces=" ">
              <itemformat command="code">
                -help
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <para>
              Give a brief usage message that is useful as a prompt and exit.
            </para>
            <anchor name="interaction-modes">
              interaction modes
            </anchor>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <findex index="fn" spaces=" ">
              <indexterm index="fn" number="1286" mergedindex="cp">
                --interaction
                <r>
                  command-line option
                </r>
              </indexterm>
            </findex>
            <item spaces=" ">
              <itemformat command="code">
                -interaction=
                <var>
                  mode
                </var>
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <cindex index="cp" spaces=" ">
              <indexterm index="cp" number="1254">
                batchmode
              </indexterm>
            </cindex>
            <cindex index="cp" spaces=" ">
              <indexterm index="cp" number="1255">
                scrollmode
              </indexterm>
            </cindex>
            <cindex index="cp" spaces=" ">
              <indexterm index="cp" number="1256">
                errorstopmode
              </indexterm>
            </cindex>
            <cindex index="cp" spaces=" ">
              <indexterm index="cp" number="1257">
                nonstopmode
              </indexterm>
            </cindex>
            <paraDefault handler: &tex;
>
               compiles a document in one of four interaction modes:
              <code>
                batchmode
              </code>
              ,
              <code>
                nonstopmode
              </code>
              ,
              <code>
                scrollmode
              </code>
              ,
              <code>
                errorstopmode
              </code>
              . In
              <dfn>
                errorstopmode
              </dfn>
               (the default),
Default handler: &tex;
               stops at each error and asks for user intervention. In
              <dfn>
                batchmode
              </dfn>
               it prints nothing on the terminal, errors are scrolled as if the user hit
              <kbd>
                RETURN
              </kbd>
               at every error, and missing files cause the job to abort. In
              <dfn>
                nonstopmode
              </dfn>
              , diagnostic message appear on the terminal but as in batch mode there is no user interaction. In
              <dfn>
                scrollmode
              </dfn>
              ,
Default handler: &tex;
               stops for missing files or keyboard input, but nothing else.
            </para>
            <para>
              For instance, starting
Default handler: &latex;
               with this command line
            </para>
            <example endspaces=" ">
              <pre xml:space="preserve">
                pdflatex -interaction=batchmode
                <var>
                  filename
                </var>
              </pre>
            </example>
            <noindent/>
            <para>
              eliminates most terminal output.
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <cindex index="cp" spaces=" ">
              <indexterm index="cp" number="1258">
                jobname
              </indexterm>
            </cindex>
            <cindex index="cp" spaces=" ">
              <indexterm index="cp" number="1259">
                filename for current job
              </indexterm>
            </cindex>
            <findex index="fn" spaces=" ">
              <indexterm index="fn" number="1287" mergedindex="cp">
                --jobname
                <r>
                  command-line option
                </r>
              </indexterm>
            </findex>
            <item spaces=" ">
              <itemformat command="code">
                -jobname=
                <var>
                  string
                </var>
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <para>
              Set the value of
Default handler: &tex;
Default handler: &textrsquo;
              s
              <dfn>
                jobname
              </dfn>
               to the string. The log file and output file will then be named
              <file>
                <var>
                  string
                </var>
                .log
              </file>
               and
              <file>
                <var>
                  string
                </var>
                .pdf
              </file>
              .
              <pxref label="Jobname">
                <xrefnodename>
                  Jobname
                </xrefnodename>
              </pxref>
              .
            </para>
            <anchor name="output-directory">
              output directory
            </anchor>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <cindex index="cp" spaces=" ">
              <indexterm index="cp" number="1260">
                output directory for all external files
              </indexterm>
            </cindex>
            <findex index="fn" spaces=" ">
              <indexterm index="fn" number="1288" mergedindex="cp">
                --output-directory
                <r>
                  command-line option
                </r>
              </indexterm>
            </findex>
            <item spaces=" ">
              <itemformat command="code">
                -output-directory=
                <var>
                  directory
                </var>
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <para>
              Write files in the directory
              <var>
                directory
              </var>
              . It must already exist. This applies to all external files created by
Default handler: &tex;
               or
Default handler: &latex;
              , such as the
              <file>
                .log
              </file>
               file for the run, the
              <file>
                .aux
              </file>
              ,
              <file>
                .toc
              </file>
              , etc., files created by
Default handler: &latex;
              , as well as the main
              <file>
                .pdf
              </file>
               or
              <file>
                .dvi
              </file>
               output file itself.
            </para>
            <para>
              When specified, the output directory
              <var>
                directory
              </var>
               is also automatically checked first for any file that it is input, so that the external files can be read back in, if desired. The true current directory (in which
Default handler: &latex;
               was run) remains unchanged, and is also checked for input files.
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <cindex index="cp" spaces=" ">
              <indexterm index="cp" number="1261">
                shell escape
              </indexterm>
            </cindex>
            <cindex index="cp" spaces=" ">
              <indexterm index="cp" number="1262">
                <code>
                  \write18
                </code>
                , enabling
              </indexterm>
            </cindex>
            <findex index="fn" spaces=" ">
              <indexterm index="fn" number="1289" mergedindex="cp">
                --enable-write18
                <r>
                  command-line option
                </r>
              </indexterm>
            </findex>
            <findex index="fn" spaces=" ">
              <indexterm index="fn" number="1290" mergedindex="cp">
                --disable-write18
                <r>
                  command-line option
                </r>
              </indexterm>
            </findex>
            <findex index="fn" spaces=" ">
              <indexterm index="fn" number="1291" mergedindex="cp">
                --shell-escape
                <r>
                  command-line option
                </r>
              </indexterm>
            </findex>
            <findex index="fn" spaces=" ">
              <indexterm index="fn" number="1292" mergedindex="cp">
                --no-shell-escape
                <r>
                  command-line option
                </r>
              </indexterm>
            </findex>
            <item spaces=" ">
              <itemformat command="code">
                --enable-write18
              </itemformat>
            </item>
            <itemx spaces=" ">
              <itemformat command="code">
                --disable-write18
              </itemformat>
            </itemx>
            <itemx spaces=" ">
              <itemformat command="code">
                --shell-escape
              </itemformat>
            </itemx>
            <itemx spaces=" ">
              <itemformat command="code">
                --no-shell-escape
              </itemformat>
            </itemx>
          </tableterm>
          <tableitem>
            <para>
              Enable or disable
              <code>
                \write18
Default handler: &lbrace;
                <var>
                  shell_command
                </var>
Default handler: &rbrace;
              </code>
               (
              <pxref label="_005cwrite18">
                <xrefnodename>
                  \write18
                </xrefnodename>
              </pxref>
              ). The first two options are supported by both
Default handler: &tex;
               Live and MiK
Default handler: &tex;
              , while the second two are synonyms supported by
Default handler: &tex;
               Live.
            </para>
            <para>
              Enabling this functionality has major security implications, since it allows a
Default handler: &latex;
               file to run any command whatsoever. Thus, by default, unrestricted
              <code>
                \write18
              </code>
               is not allowed. (The default for
Default handler: &tex;
               Live, Mac
Default handler: &tex;
              , and MiK
Default handler: &tex;
               is to allow the execution of a limited number of
Default handler: &tex;
              -related programs, which they distribute.)
            </para>
            <para>
              For example, if you invoke
Default handler: &latex;
               with the option
              <code>
                no-shell-escape
              </code>
              , and in your document you call
              <code>
                \write18
Default handler: &lbrace;
                ls -l
Default handler: &rbrace;
              </code>
              , then you do not get an error but the log file says
              <samp>
                runsystem(ls -l)...disabled
              </samp>
              .
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <findex index="fn" spaces=" ">
              <indexterm index="fn" number="1293" mergedindex="cp">
                --halt-on-error
                <r>
                  command-line option
                </r>
              </indexterm>
            </findex>
            <item spaces=" ">
              <itemformat command="code">
                -halt-on-error
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <para>
              Stop processing at the first error.
            </para>
          </tableitem>
        </tableentry>
        <tableentry>
          <tableterm>
            <findex index="fn" spaces=" ">
              <indexterm index="fn" number="1294" mergedindex="cp">
                --file-line-error
                <r>
                  command-line option
                </r>
              </indexterm>
            </findex>
            <findex index="fn" spaces=" ">
              <indexterm index="fn" number="1295" mergedindex="cp">
                --no-file-line-error
                <r>
                  command-line option
                </r>
              </indexterm>
            </findex>
            <item spaces=" ">
              <itemformat command="code">
                -file-line-error
              </itemformat>
            </item>
          </tableterm>
        </tableentry>
        <tableentry>
          <tableterm>
            <item spaces=" ">
              <itemformat command="code">
                -no-file-line-error
              </itemformat>
            </item>
          </tableterm>
          <tableitem>
            <para>
              Enable or disable
              <code>
                <var>
                  filename
                </var>
                :
                <var>
                  lineno
                </var>
                :
                <var>
                  error
                </var>
              </code>
              -style error messages. These are only available with
Default handler: &tex;
               Live or Mac
Default handler: &tex;
              .
            </para>
          </tableitem>
        </tableentry>
      </table>
    </section>
    <node name="Command-line-input" spaces=" ">
      <nodename>
        Command line input
      </nodename>
      <nodenext automatic="on">
        Jobname
      </nodenext>
      <nodeprev automatic="on">
        Command line options
      </nodeprev>
      <nodeup automatic="on">
        Command line interface
      </nodeup>
    </node>
    <section spaces=" ">
      <sectiontitle>
        Command line input
      </sectiontitle>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="1263">
          input, on command line
        </indexterm>
      </cindex>
      <para>
        As part of the command line invocation
      </para>
      <example endspaces=" ">
        <pre xml:space="preserve">
          <var>
            latex-engine
          </var>
          <var>
            options
          </var>
          <var>
            argument
          </var>
        </pre>
      </example>
      <noindent/>
      <para>
        you can specify arbitrary
Default handler: &latex;
         input by starting
        <var>
          argument
        </var>
         with a backslash. (All the engines support this.) This allows you to do some special effects.
      </para>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="1264">
          <r>
            package
          </r>
          ,
          <code>
            hyperref
          </code>
        </indexterm>
      </cindex>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="1265">
          <code>
            hyperref
          </code>
          <r>
            package
          </r>
        </indexterm>
      </cindex>
      <para>
        For example, this file (which uses the
        <code>
          hyperref
        </code>
         package for hyperlinks) can produce two kinds of output, one to be read on physical paper and one to be read online.
      </para>
      <example endspaces=" ">
        <pre xml:space="preserve">
          \ifdefined\paperversion % in preamble \newcommand
Default handler: &lbrace;
          \urlcolor
Default handler: &rbrace;
Default handler: &lbrace;
          black
Default handler: &rbrace;
           \else \newcommand
Default handler: &lbrace;
          \urlcolor
Default handler: &rbrace;
Default handler: &lbrace;
          blue
Default handler: &rbrace;
           \fi \usepackage[colorlinks=true,urlcolor=\urlcolor]
Default handler: &lbrace;
          hyperref
Default handler: &rbrace;
           ... \href
Default handler: &lbrace;
          https://www.ctan.org
Default handler: &rbrace;
Default handler: &lbrace;
          CTAN
Default handler: &rbrace;
           % in body ...
        </pre>
      </example>
      <noindent/>
      <para>
        Compiling this document
        <file>
          book.tex
        </file>
         with the command line
        <code>
          pdflatex book
        </code>
         will give the
        <samp>
          CTAN
        </samp>
         link in blue. But compiling it with
      </para>
      <example endspaces=" ">
        <pre xml:space="preserve">
          pdflatex
          "
          \def\paperversion
Default handler: &lbrace;
Default handler: &rbrace;
          \input book.tex
          "
        </pre>
      </example>
      <noindent/>
      <para>
        has the link in black. We use double quotes to prevent interpretation of the symbols by the command line shell. (This usually works on both Unix and Windows systems, but there are many peculiarities to shell quoting, so read your system documentation if need be.)
      </para>
      <para>
        In a similar way, from the single file
        <file>
          main.tex
        </file>
         you can compile two different versions.
      </para>
Default handler: <!-- c credit Paul Gaborit: https://tex.stackexchange.com/a/220101/121234 -->
      <example endspaces=" ">
        <pre xml:space="preserve">
          pdflatex -jobname=students
          "
          \def\student
Default handler: &lbrace;
Default handler: &rbrace;
          \input
Default handler: &lbrace;
          main
Default handler: &rbrace;
          "
           pdflatex -jobname=teachers
          "
          \def\teachers
Default handler: &lbrace;
Default handler: &rbrace;
          \input
Default handler: &lbrace;
          main
Default handler: &rbrace;
          "
        </pre>
      </example>
      <noindent/>
      <para>
        The
        <code>
          jobname
        </code>
         option is there because otherwise both files would be called
        <file>
          main.pdf
        </file>
         and the second would overwrite the first (
        <pxref label="Jobname">
          <xrefnodename>
            Jobname
          </xrefnodename>
        </pxref>
        ).
      </para>
      <para>
        In this example we use the command line to select which parts of a document to include. For a book named
        <file>
          mybook.tex
        </file>
         and structured like this.
      </para>
      <example endspaces=" ">
        <pre xml:space="preserve">
          \documentclass
Default handler: &lbrace;
          book
Default handler: &rbrace;
           \begin
Default handler: &lbrace;
          document
Default handler: &rbrace;
           ... \include
Default handler: &lbrace;
          chap1
Default handler: &rbrace;
           \include
Default handler: &lbrace;
          chap2
Default handler: &rbrace;
           ... \end
Default handler: &lbrace;
          document
Default handler: &rbrace;
        </pre>
      </example>
      <noindent/>
      <para>
        the command line
      </para>
      <example endspaces=" ">
        <pre xml:space="preserve">
          pdflatex
          "
          \includeonly
Default handler: &lbrace;
          chap1
Default handler: &rbrace;
          \input
Default handler: &lbrace;
          mybook
Default handler: &rbrace;
          "
        </pre>
      </example>
      <noindent/>
      <para>
        will give output that has the first chapter but no other chapter.
        <xref label="Splitting-the-input">
          <xrefnodename>
            Splitting the input
          </xrefnodename>
        </xref>
        .
      </para>
    </section>
    <node name="Jobname" spaces=" ">
      <nodename>
        Jobname
      </nodename>
      <nodenext automatic="on">
        Recovering from errors
      </nodenext>
      <nodeprev automatic="on">
        Command line input
      </nodeprev>
      <nodeup automatic="on">
        Command line interface
      </nodeup>
    </node>
    <section spaces=" ">
      <sectiontitle>
        Jobname
      </sectiontitle>
      <findex index="fn" spaces=" ">
        <indexterm index="fn" number="1296" mergedindex="cp">
          <code>
            \jobname
          </code>
        </indexterm>
      </findex>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="1266">
          jobname
        </indexterm>
      </cindex>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="1267">
          document root name
        </indexterm>
      </cindex>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="1268">
          name of document root
        </indexterm>
      </cindex>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="1269">
          root file
        </indexterm>
      </cindex>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="1270">
          file, root
        </indexterm>
      </cindex>
      <para>
        Running
Default handler: &latex;
         creates a number of files, including the main PDF (or DVI) output but also including others. These files are named with the so-called
        <dfn>
          jobname
        </dfn>
        . The most common case is also the simplest, where for instance the command
        <code>
          pdflatex thesis
        </code>
         creates
        <code>
          thesis.pdf
        </code>
         and also
        <code>
          thesis.log
        </code>
         and
        <code>
          thesis.aux
        </code>
        . Here the job name is
        <code>
          thesis
        </code>
        .
      </para>
      <para>
        In general,
Default handler: &latex;
         is invoked as
        <code>
          <var>
            latex-engine
          </var>
          <var>
            options
          </var>
          <var>
            argument
          </var>
        </code>
        , where
        <var>
          latex-engine
        </var>
         is
        <command>
          pdflatex
        </command>
        ,
        <command>
          lualatex
        </command>
        , etc.
Default handler: &noeos;
         (
        <pxref label="TeX-engines">
          <xrefnodenameDefault handler: &tex;
>
             engines
          </xrefnodename>
        </pxref>
        ). If
        <var>
          argument
        </var>
         does not start with a backslash, as is the case above with
        <code>
          thesis
        </code>
        , then
Default handler: &tex;
         considers it to be the name of the file to input as the main document. This file is referred to as the
        <dfn>
          root file
        </dfn>
         (
        <pxref label="Splitting-the-input">
          <xrefnodename>
            Splitting the input
          </xrefnodename>
        </pxref>
        , and
        <ref label="_005cinput">
          <xrefnodename>
            \input
          </xrefnodename>
        </ref>
        ). The name of that root file, without the
        <file>
          .tex
        </file>
         extension if any, is the jobname. If
        <var>
          argument
        </var>
         does start with a backslash, or if
Default handler: &tex;
         is in interactive mode, then it waits for the first
        <code>
          \input
        </code>
         command, and the jobname is the argument to
        <code>
          \input
        </code>
        .
      </para>
      <para>
        There are two more possibilities for the jobname. It can be directly specified with the
        <code>
          -jobname
        </code>
         option, as in
        <code>
          pdflatex -jobname=myname
        </code>
         (
        <pxref label="Command-line-input">
          <xrefnodename>
            Command line input
          </xrefnodename>
        </pxref>
         for a practical example).
      </para>
      <findex index="fn" spaces=" ">
        <indexterm index="fn" number="1297" mergedindex="cp">
          texput
          <r>
            , jobname default
          </r>
        </indexterm>
      </findex>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="1271">
          fallback jobname
        </indexterm>
      </cindex>
      <para>
        The final possibility is
        <file>
          texput
        </file>
        , which is the final fallback default if no other name is available to
Default handler: &tex;
        . That is, if no
        <code>
          -jobname
        </code>
         option was specified, and the compilation stops before any input file is met, then the log file will be named
        <file>
          texput.log
        </file>
        .
      </para>
      <findex index="fn" spaces=" ">
        <indexterm index="fn" number="1298" mergedindex="cp">
          \documentclass
          <r>
            , and
            <code>
              texput
            </code>
             jobname
          </r>
        </indexterm>
      </findex>
      <findex index="fn" spaces=" ">
        <indexterm index="fn" number="1299" mergedindex="cp">
          \RequirePackage
          <r>
            , and
            <code>
              texput
            </code>
             jobname
          </r>
        </indexterm>
      </findex>
      <para>
        A special case of this is that in
Default handler: &latex;
         versions of (approximately) 2020 or later, the jobname is also
        <file>
          texput
        </file>
         if the first
        <code>
          \input
        </code>
         occurs as a result of being called by either
        <code>
          \documentclass
        </code>
         or
        <code>
          \RequirePackage
        </code>
        . So this will produce a file named
        <file>
          texput.pdf
        </file>
        :
      </para>
      <example endspaces=" ">
        <pre xml:space="preserve">
          pdflatex
          "
          \documentclass
Default handler: &lbrace;
          minimal
Default handler: &rbrace;
          \begin
Default handler: &lbrace;
          document
Default handler: &rbrace;
          Hello!\end
Default handler: &lbrace;
          document
Default handler: &rbrace;
          "
        </pre>
      </example>
      <para>
        However, this special case only applies to those two commands. Thus, with
      </para>
Default handler: <!-- c credit Herbert Voss: https://tex.stackexchange.com/a/17236/121234 -->
      <example endspaces=" ">
        <pre xml:space="preserve">
          pdflatex
          "
          \documentclass
Default handler: &lbrace;
          article
Default handler: &rbrace;
          \usepackage
Default handler: &lbrace;
          lipsum
Default handler: &rbrace;
          \input
Default handler: &lbrace;
          thesis
Default handler: &rbrace;
          "
        </pre>
      </example>
      <noindent/>
      <para>
        the output file is
        <file>
          lipsum.pdf
        </file>
        , as
        <code>
          \usepackage
        </code>
         calls
        <code>
          \input
        </code>
        .
      </para>
      <findex index="fn" spaces=" ">
        <indexterm index="fn" number="1300" mergedindex="cp">
          \jobname
        </indexterm>
      </findex>
      <para>
        Within the document, the macro
        <code>
          \jobname
        </code>
         expands to the jobname. (When you run
Default handler: &latex;
         on a file whose name contains spaces, the string returned by
        <code>
          \jobname
        </code>
         contains matching start and end quotes.) In the expansion of that macro, all characters are of catcode
Default handler: &nbsp;
        12 (other) except that spaces are category
Default handler: &nbsp;
        10, including letters that are normally catcode
Default handler: &nbsp;
        11.
      </para>
      <findex index="fn" spaces=" ">
        <indexterm index="fn" number="1301" mergedindex="cp">
          \IfBeginWith*
          <r>
             macro from
            <file>
              xstring
            </file>
          </r>
        </indexterm>
      </findex>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="1272">
          <r>
            package
          </r>
          ,
          <code>
            xstring
          </code>
        </indexterm>
      </cindex>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="1273">
          <code>
            xstring
          </code>
          <r>
            package
          </r>
        </indexterm>
      </cindex>
      <para>
        Because of this catcode situation, using the jobname in a conditional can become complicated. One solution is to use the macro
        <code>
          \IfBeginWith
        </code>
         from the
        <file>
          xstring
        </file>
         package in its star variant, which is insensitive to catcode. For example, in the following text the footnote
Default handler: &textldquo;
        Including Respublica Bananensis Francorum.
Default handler: &textrdquo;
Default handler: &noeos;
         is only present if the task name starts with
        <file>
          my-doc
        </file>
        .
      </para>
      <example endspaces=" ">
        <pre xml:space="preserve">
          If a democracy is just a regime where citizens vote then all banana republics \IfBeginWith*
Default handler: &lbrace;
          \jobname
Default handler: &rbrace;
Default handler: &lbrace;
          my-doc
Default handler: &rbrace;
          %
Default handler: &lbrace;
          \footnote
Default handler: &lbrace;
          Including Respublica Bananensis Francorum.
Default handler: &rbrace;
Default handler: &rbrace;
Default handler: &lbrace;
Default handler: &rbrace;
           are democracies.
        </pre>
      </example>
      <para>
        Manipulating the value of
        <code>
          \jobname
        </code>
         inside of a document does not change the name of the output file or the log file.
      </para>
    </section>
    <node name="Recovering-from-errors" spaces=" ">
      <nodename>
        Recovering from errors
      </nodename>
      <nodeprev automatic="on">
        Jobname
      </nodeprev>
      <nodeup automatic="on">
        Command line interface
      </nodeup>
    </node>
    <section spaces=" ">
      <sectiontitle>
        Recovering from errors
      </sectiontitle>
      <para>
        If
Default handler: &latex;
         finds an error in your document then it gives you an error message and prompts you with a question mark,
        <code>
          ?
        </code>
        . For instance, running
Default handler: &latex;
         on this file
      </para>
      <example endspaces=" ">
        <pre xml:space="preserve">
          \newcommand
Default handler: &lbrace;
          \NP
Default handler: &rbrace;
Default handler: &lbrace;
          \ensuremath
Default handler: &lbrace;
          \textbf
Default handler: &lbrace;
          NP
Default handler: &rbrace;
Default handler: &rbrace;
Default handler: &rbrace;
           The \PN
Default handler: &lbrace;
Default handler: &rbrace;
           problem is a million dollar one.
        </pre>
      </example>
      <noindent/>
      <para>
        causes it show this, and wait for input.
      </para>
      <example endspaces=" ">
        <pre xml:space="preserve">
          ! Undefined control sequence. l.5 The \PN
Default handler: &lbrace;
Default handler: &rbrace;
           problem is a million dollar one. ?
        </pre>
      </example>
      <noindent/>
      <para>
        The simplest thing is to enter
        <kbd>
          x
        </kbd>
         and
        <kbd>
          RETURN
        </kbd>
         and fix the typo. You could instead enter
        <kbd>
          ?
        </kbd>
         and
        <kbd>
          RETURN
        </kbd>
         to see other options.
      </para>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="1274">
          <samp>
            *
          </samp>
           prompt
        </indexterm>
      </cindex>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="1275">
          prompt,
          <samp>
            *
          </samp>
        </indexterm>
      </cindex>
      <findex index="fn" spaces=" ">
        <indexterm index="fn" number="1302" mergedindex="cp">
          \stop
        </indexterm>
      </findex>
      <para>
        There are two other error scenarios. The first is that you forgot to include the
        <code>
          \end
Default handler: &lbrace;
          document
Default handler: &rbrace;
        </code>
         or misspelled it. In this case
Default handler: &latex;
         gives you a
        <samp>
          *
        </samp>
         prompt. You can get back to the command line by typing
        <kbd>
          \stop
        </kbd>
         and
        <kbd>
          RETURN
        </kbd>
        ; this command does its best to exit
Default handler: &latex;
         immediately, whatever state it may be in.
      </para>
      <para>
        The last scenario is that you mistyped the filename. For instance, instead of
        <code>
          pdflatex test
        </code>
         you might type
        <code>
          pdflatex tste
        </code>
        .
      </para>
      <example endspaces=" ">
        <pre xml:space="preserve">
          ! I can't find file `tste'.
          <
          *
          >
           tste (Press Enter to retry, or Control-D to exit) Please type another input file name:
        </pre>
      </example>
      <noindent/>
      <para>
        The simplest thing is to enter
        <kbd>
          CTRL d
        </kbd>
         (holding the Control and d keys down at the same time), and then retype the correct command line.
      </para>
    </section>
  </chapter>
  <node name="Document-templates" spaces=" ">
    <nodename>
      Document templates
    </nodename>
    <nodenext automatic="on">
      Index
    </nodenext>
    <nodeprev automatic="on">
      Command line interface
    </nodeprev>
    <nodeup automatic="on">
      Top
    </nodeup>
  </node>
  <appendix spaces=" ">
    <sectiontitle>
      Document templates
    </sectiontitle>
    <cindex index="cp" spaces=" ">
      <indexterm index="cp" number="1276">
        document templates
      </indexterm>
    </cindex>
    <cindex index="cp" spaces=" ">
      <indexterm index="cp" number="1277">
        templates, document
      </indexterm>
    </cindex>
    <para>
      Although illustrative material, perhaps these document templates will be useful. Additional template resources are listed at
      <url>
        <urefurl>
          https://tug.org/interest.html#latextemplates
        </urefurl>
      </url>
      .
    </para>
    <menu endspaces=" ">
      <menuentry>
        <menuleadingtext>
          *
        </menuleadingtext>
        <menunode>
          beamer template
        </menunode>
        <menuseparator>
          ::
        </menuseparator>
        <menudescription>
          <pre xml:space="preserve"/>
        </menudescription>
      </menuentry>
      <menuentry>
        <menuleadingtext>
          *
        </menuleadingtext>
        <menunode>
          article template
        </menunode>
        <menuseparator>
          ::
        </menuseparator>
        <menudescription>
          <pre xml:space="preserve"/>
        </menudescription>
      </menuentry>
      <menuentry>
        <menuleadingtext>
          *
        </menuleadingtext>
        <menunode>
          book template
        </menunode>
        <menuseparator>
          ::
        </menuseparator>
        <menudescription>
          <pre xml:space="preserve"/>
        </menudescription>
      </menuentry>
      <menuentry>
        <menuleadingtext>
          *
        </menuleadingtext>
        <menunode>
          Larger book template
        </menunode>
        <menuseparator>
          ::
        </menuseparator>
        <menudescription>
          <pre xml:space="preserve"/>
        </menudescription>
      </menuentry>
    </menu>
    <node name="beamer-template" spaces=" ">
      <nodename>
        beamer template
      </nodename>
      <nodenext automatic="on">
        article template
      </nodenext>
      <nodeup automatic="on">
        Document templates
      </nodeup>
    </node>
    <section spaces=" ">
      <sectiontitle>
        <code>
          beamer
        </code>
         template
      </sectiontitle>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="1278">
          <code>
            beamer
          </code>
           template and class
        </indexterm>
      </cindex>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="1279">
          template,
          <code>
            beamer
          </code>
        </indexterm>
      </cindex>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="1280">
          <r>
            package
          </r>
          ,
          <code>
            beamer
          </code>
        </indexterm>
      </cindex>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="1281">
          <code>
            beamer
          </code>
          <r>
            package
          </r>
        </indexterm>
      </cindex>
      <para>
        The
        <code>
          beamer
        </code>
         class creates presentation slides. It has a vast array of features, but here is a basic template:
      </para>
      <verbatim xml:space="preserve" endspaces=" ">
         \documentclass{beamer} \title{Beamer Class template} \author{Alex Author} \date{July 31, 2020} \begin{document} \maketitle % without [fragile], any {verbatim} code gets mysterious errors. \begin{frame}[fragile] \frametitle{First Slide} \begin{verbatim} This is \verbatim! \end{verbatim} \end{frame} \end{document}
      </verbatim>
      <para>
        The Beamer package on CTAN:
        <url>
          <urefurl>
            https://ctan.org/pkg/beamer
          </urefurl>
        </url>
        .
      </para>
    </section>
    <node name="article-template" spaces=" ">
      <nodename>
        article template
      </nodename>
      <nodenext automatic="on">
        book template
      </nodenext>
      <nodeprev automatic="on">
        beamer template
      </nodeprev>
      <nodeup automatic="on">
        Document templates
      </nodeup>
    </node>
    <section spaces=" ">
      <sectiontitle>
        <code>
          article
        </code>
         template
      </sectiontitle>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="1282">
          template (simple),
          <code>
            article
          </code>
        </indexterm>
      </cindex>
      <para>
        A simple template for an article.
      </para>
      <verbatim xml:space="preserve" endspaces=" ">
         \documentclass{article} \title{Article Class Template} \author{Alex Author} \begin{document} \maketitle \section{First section} Some text. \subsection{First section, first subsection} Additional text. \section{Second section} Some more text. \end{document}
      </verbatim>
    </section>
    <node name="book-template" spaces=" ">
      <nodename>
        book template
      </nodename>
      <nodenext automatic="on">
        Larger book template
      </nodenext>
      <nodeprev automatic="on">
        article template
      </nodeprev>
      <nodeup automatic="on">
        Document templates
      </nodeup>
    </node>
    <section spaces=" ">
      <sectiontitle>
        <code>
          book
        </code>
         template
      </sectiontitle>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="1283">
          template,
          <code>
            book
          </code>
        </indexterm>
      </cindex>
      <para>
        This is a straightforward template for a book.
        <xref label="Larger-book-template">
          <xrefnodename>
            Larger book template
          </xrefnodename>
        </xref>
        , for a more elaborate one.
      </para>
      <verbatim xml:space="preserve" endspaces=" ">
         \documentclass{book} \title{Book Class Template} \author{Alex Author} \begin{document} \maketitle \chapter{First} Some text. \chapter{Second} Some other text. \section{A subtopic} The end. \end{document}
      </verbatim>
    </section>
    <node name="Larger-book-template" spaces=" ">
      <nodename>
        Larger book template
      </nodename>
      <nodeprev automatic="on">
        book template
      </nodeprev>
      <nodeup automatic="on">
        Document templates
      </nodeup>
    </node>
    <section spaces=" ">
      <sectiontitle>
        Larger
        <code>
          book
        </code>
         template
      </sectiontitle>
      <cindex index="cp" spaces=" ">
        <indexterm index="cp" number="1284">
          template,
          <code>
            book
          </code>
        </indexterm>
      </cindex>
      <para>
        This is a somewhat elaborate template for a book.
        <xref label="book-template">
          <xrefnodename>
            book template
          </xrefnodename>
        </xref>
        , for a simpler one.
      </para>
      <para>
        This template uses
        <code>
          \frontmatter
        </code>
        ,
        <code>
          \mainmatter
        </code>
        , and
        <code>
          \backmatter
        </code>
         to control the typography of the three main areas of a book (
        <pxref label="_005cfrontmatter-_0026-_005cmainmatter-_0026-_005cbackmatter">
          <xrefnodename>
            \frontmatter
            &
             \mainmatter
            &
             \backmatter
          </xrefnodename>
        </pxref>
        ). The book has a bibliography and an index.
      </para>
      <para>
        Also notable is that it uses
        <code>
          \include
        </code>
         and
        <code>
          \includeonly
        </code>
         (
        <pxref label="Splitting-the-input">
          <xrefnodename>
            Splitting the input
          </xrefnodename>
        </pxref>
        ). While you are working on a chapter you can comment out all the other chapter entries from the argument to
        <code>
          \includeonly
        </code>
        . That will speed up compilation without losing any information such as cross-references. (Material that does not need to come on a new page is brought in with
        <code>
          \input
        </code>
         instead of
        <code>
          \include
        </code>
        . You don
Default handler: &textrsquo;
        t get the cross-reference benefit with
        <code>
          \input
        </code>
        .)
      </para>
      <verbatim xml:space="preserve" endspaces=" ">
         \documentclass[titlepage]{book} \usepackage{makeidx}\makeindex \title{Book Class Template} \author{Alex Author} \includeonly{% % frontcover, preface, chap1, % appenA, } \begin{document} \frontmatter \include{frontcover} % maybe comment out while drafting: \maketitle \input{dedication} \input{copyright} \tableofcontents \include{preface} \mainmatter \include{chap1} ... \appendix \include{appenA} ... \backmatter \bibliographystyle{apalike} \addcontentsline{toc}{chapter}{Bibliography} \bibliography \addcontentsline{toc}{chapter}{Index} \printindex \include{backcover} \end{document}
      </verbatim>
    </section>
  </appendix>
  <node name="Index" spaces=" ">
    <nodename>
      Index
    </nodename>
    <nodeprev automatic="on">
      Document templates
    </nodeprev>
    <nodeup automatic="on">
      Top
    </nodeup>
  </node>
  <unnumbered spaces=" ">
    <sectiontitle>
      Index
    </sectiontitle>
Default handler: <!-- c Keep `Command Index' working for ltx-help.el. -->
    <anchor name="Command-Index">
      Command Index
    </anchor>
    <printindex spaces=" " value="cp" line="cp"/>
  </unnumbered>
  <bye/>
  <postambleafterend>
     \def\DeclareTextCommand{\foo}{T1} % then |\foo| is defined to be |\T1-cmd \foo \T1\foo|, % % where |\T1\foo| is \emph{one} control sequence, not two! \newcommand \def\ProvideTextCommand % same with \providecommand \@onlypreamble\DeclareTextCommand \@onlypreamble\DeclareTextSymbol \gdef\TextSymbolUnavailable#1{% \@onlypreamble\def\DeclareTextCommandDefault#1{% \def\ProvideTextCommandDefault#1{% \def\DeclareTextAccent#1#2#3{% \def\DeclareTextCompositeCommand#1#2#3#4{% \@onlypreamble\def\DeclareTextComposite#1#2#3#4{% \def\UseTextAccent#1#2#3{% \def\UseTextSymbol#1#2{% \@onlypreamble\DeclareTextSymbolDefault@item \@onlypreamble\DeclareTextAccentDefault@item \def\UndeclareTextCommand#1#2{% @c Local Variables: @c ispell-dictionary:
    "
    english
    "
     @c coding: latin-1-unix @c End:
  </postambleafterend>
</texinfo>