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/* @(#)s_ldexp.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
<<ldexp>>, <<ldexpf>>---load exponent
INDEX
ldexp
INDEX
ldexpf
ANSI_SYNOPSIS
#include <math.h>
double ldexp(double <[val]>, int <[exp]>);
float ldexpf(float <[val]>, int <[exp]>);
TRAD_SYNOPSIS
#include <math.h>
double ldexp(<[val]>, <[exp]>)
double <[val]>;
int <[exp]>;
float ldexpf(<[val]>, <[exp]>)
float <[val]>;
int <[exp]>;
DESCRIPTION
<<ldexp>> calculates the value
@ifnottex
<[val]> times 2 to the power <[exp]>.
@end ifnottex
@tex
$val\times 2^{exp}$.
@end tex
<<ldexpf>> is identical, save that it takes and returns <<float>>
rather than <<double>> values.
RETURNS
<<ldexp>> returns the calculated value.
Underflow and overflow both set <<errno>> to <<ERANGE>>.
On underflow, <<ldexp>> and <<ldexpf>> return 0.0.
On overflow, <<ldexp>> returns plus or minus <<HUGE_VAL>>.
PORTABILITY
<<ldexp>> is ANSI, <<ldexpf>> is an extension.
*/
#include "fdlibm.h"
#include <errno.h>
#ifndef _DOUBLE_IS_32BITS
#ifdef __STDC__
double ldexp(double value, int exp)
#else
double ldexp(value, exp)
double value; int exp;
#endif
{
if(!finite(value)||value==0.0) return value;
value = scalbn(value,exp);
if(!finite(value)||value==0.0) errno = ERANGE;
return value;
}
#endif /* _DOUBLE_IS_32BITS */
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