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/* @(#)s_copysign.c 5.1 93/09/24 */
/*
* ====================================================
* Copyright (C) 1993 by Sun Microsystems, Inc. All rights reserved.
*
* Developed at SunPro, a Sun Microsystems, Inc. business.
* Permission to use, copy, modify, and distribute this
* software is freely granted, provided that this notice
* is preserved.
* ====================================================
*/
/*
FUNCTION
<<copysign>>, <<copysignf>>---sign of <[y]>, magnitude of <[x]>
INDEX
copysign
INDEX
copysignf
ANSI_SYNOPSIS
#include <math.h>
double copysign (double <[x]>, double <[y]>);
float copysignf (float <[x]>, float <[y]>);
TRAD_SYNOPSIS
#include <math.h>
double copysign (<[x]>, <[y]>)
double <[x]>;
double <[y]>;
float copysignf (<[x]>, <[y]>)
float <[x]>;
float <[y]>;
DESCRIPTION
<<copysign>> constructs a number with the magnitude (absolute value)
of its first argument, <[x]>, and the sign of its second argument,
<[y]>.
<<copysignf>> does the same thing; the two functions differ only in
the type of their arguments and result.
RETURNS
<<copysign>> returns a <<double>> with the magnitude of
<[x]> and the sign of <[y]>.
<<copysignf>> returns a <<float>> with the magnitude of
<[x]> and the sign of <[y]>.
PORTABILITY
<<copysign>> is not required by either ANSI C or the System V Interface
Definition (Issue 2).
*/
/*
* copysign(double x, double y)
* copysign(x,y) returns a value with the magnitude of x and
* with the sign bit of y.
*/
#include "fdlibm.h"
#ifndef _DOUBLE_IS_32BITS
#ifdef __STDC__
double copysign(double x, double y)
#else
double copysign(x,y)
double x,y;
#endif
{
__uint32_t hx,hy;
GET_HIGH_WORD(hx,x);
GET_HIGH_WORD(hy,y);
SET_HIGH_WORD(x,(hx&0x7fffffff)|(hy&0x80000000));
return x;
}
#endif /* _DOUBLE_IS_32BITS */
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