\" $NetBSD: copysign.3,v 1.4 2017/09/28 15:03:18 maya Exp $
\"
\" Copyright (c) 2011 Jukka Ruohonen <
[email protected]>
\" All rights reserved.
\"
\" Redistribution and use in source and binary forms, with or without
\" modification, are permitted provided that the following conditions
\" are met:
\" 1. Redistributions of source code must retain the above copyright
\" notice, this list of conditions and the following disclaimer.
\" 2. Redistributions in binary form must reproduce the above copyright
\" notice, this list of conditions and the following disclaimer in the
\" documentation and/or other materials provided with the distribution.
\"
\" THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
\" ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
\" TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
\" PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
\" BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
\" CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
\" SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
\" INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
\" CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
\" ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
\" POSSIBILITY OF SUCH DAMAGE.
\"
Dd September 28, 2017
Dt COPYSIGN 3
Os
Sh NAME
Nm copysign ,
Nm copysignf ,
Nm copysignl
Nd functions to manipulate signs
Sh LIBRARY
Lb libm
Sh SYNOPSIS
In math.h
Ft double
Fn copysign "double x" "double y"
Ft float
Fn copysignf "float x" "float y"
Ft long double
Fn copysignl "long double x" "long double y"
In tgmath.h
Ft real-floating
Fn copysign "real-floating x" "real-floating y"
Sh DESCRIPTION
The
Fn copysign ,
Fn copysignf ,
and
Fn copysignl
functions return a value whose absolute value matches
Fa x ,
but whose sign bit is taken from
Fa y .
Sh RETURN VALUES
Upon successful completion,
all three functions return a value with the magnitude of
Fa x
and the sign of
Fa y .
If
Fa x
is
\*(Na ,
the functions return a
\*(Na
with the sign of
Fa y .
Sh SEE ALSO
Xr math 3 ,
Xr signbit 3
Sh STANDARDS
The described functions conform to
St -isoC-99 .
\"
\" XXX: Verify this.
\"
\" The functions are also recommended by
\" .St -ieee754
\"
\" .Sh HISTORY
\"
\" XXX: Fill this.
\"
\" These functions first appeared in ???.
\"
Sh CAVEATS
Note that on implementations that represent a signed zero
but do not treat negative zero consistently in arithmetic operations,
these functions may regard the sign of zero as positive.
