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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 */