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/* @(#)z_fabs.c 1.0 98/08/13 */
/*
FUNCTION
<<fabs>>, <<fabsf>>---absolute value (magnitude)
INDEX
fabs
INDEX
fabsf
ANSI_SYNOPSIS
#include <math.h>
double fabs(double <[x]>);
float fabsf(float <[x]>);
TRAD_SYNOPSIS
#include <math.h>
double fabs(<[x]>)
double <[x]>;
float fabsf(<[x]>)
float <[x]>;
DESCRIPTION
<<fabs>> and <<fabsf>> calculate
@tex
$|x|$,
@end tex
the absolute value (magnitude) of the argument <[x]>, by direct
manipulation of the bit representation of <[x]>.
RETURNS
The calculated value is returned.
PORTABILITY
<<fabs>> is ANSI.
<<fabsf>> is an extension.
*/
/******************************************************************
* Floating-Point Absolute Value
*
* Input:
* x - floating-point number
*
* Output:
* absolute value of x
*
* Description:
* fabs computes the absolute value of a floating point number.
*
*****************************************************************/
#include "fdlibm.h"
#include "zmath.h"
#ifndef _DOUBLE_IS_32BITS
double
_DEFUN (fabs, (double),
double x)
{
switch (numtest (x))
{
case NAN:
errno = EDOM;
return (x);
case INF:
errno = ERANGE;
return (x);
case 0:
return (0.0);
default:
return (x < 0.0 ? -x : x);
}
}
#endif /* _DOUBLE_IS_32BITS */
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