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/* Copyright (C) 2002 by Red Hat, Incorporated. All rights reserved.
*
* Permission to use, copy, modify, and distribute this software
* is freely granted, provided that this notice is preserved.
*/
/*
FUNCTION
<<fdim>>, <<fdimf>>---positive difference
INDEX
fdim
INDEX
fdimf
SYNOPSIS
#include <math.h>
double fdim(double <[x]>, double <[y]>);
float fdimf(float <[x]>, float <[y]>);
DESCRIPTION
The <<fdim>> functions determine the positive difference between their
arguments, returning:
. <[x]> - <[y]> if <[x]> > <[y]>, or
@ifnottex
. +0 if <[x]> <= <[y]>, or
@end ifnottex
@tex
. +0 if <[x]> $\leq$ <[y]>, or
@end tex
. NAN if either argument is NAN.
A range error may occur.
RETURNS
The <<fdim>> functions return the positive difference value.
PORTABILITY
ANSI C, POSIX.
*/
#include "fdlibm.h"
#ifdef _NEED_FLOAT64
__float64
fdim64(__float64 x, __float64 y)
{
if (isnan(x) || isnan(y)) return(x+y);
__float64 z = x > y ? x - y : _F_64(0.0);
if (!isinf(x) && !isinf(y))
z = check_oflow(z);
return z;
}
_MATH_ALIAS_d_dd(fdim)
#endif /* _NEED_FLOAT64 */
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