%%
%% A DANTE-Edition example
%%
%% Example 16-03-5 on page 238.
%%
%% Copyright (C) 2011 Herbert Voss
%%
%% It may be distributed and/or modified under the conditions
%% of the LaTeX Project Public License, either version 1.3
%% of this license or (at your option) any later version.
%%
%% See
http://www.latex-project.org/lppl.txt for details.
%%
%%
%% ====
% Show page(s) 1
%%
\documentclass[]{article}
\pagestyle{empty}
\setlength\textwidth{129.70511pt}
\setlength\parindent{0pt}
\usepackage{pstricks,pst-node}\SpecialCoor
\makeatletter \def\nodeBetween(#1)(#2)#3{%
\pst@getcoor{#1}\pst@tempa\pst@getcoor{#2}\pst@tempb
\pnode(! \pst@tempa /YA exch \pst@number\psyunit div def
/XA exch \pst@number\psxunit div def
\pst@tempb /YB exch \pst@number\psyunit div def
/XB exch \pst@number\psxunit div def
XB XA add 2 div YB YA add 2 div){#3}}\makeatother
\begin{document}
\begin{pspicture}[showgrid](3,2)
\psline[linestyle=dashed]{o-o}(0.25,0.33)(2.333,2)
\nodeBetween(0.25,0.33)(2.333,2){centre}\pscircle*(centre){3pt}
\end{pspicture}
\end{document}
