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/* @(#)w_exp2.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
<<exp2>>, <<exp2f>>---exponential, base 2
INDEX
exp2
INDEX
exp2f
SYNOPSIS
#include <math.h>
double exp2(double <[x]>);
float exp2f(float <[x]>);
DESCRIPTION
<<exp2>> and <<exp2f>> calculate 2 ^ <[x]>, that is,
@ifnottex
2 raised to the power <[x]>.
@end ifnottex
@tex
$2^x$
@end tex
You can use the (non-ANSI) function <<matherr>> to specify
error handling for these functions.
RETURNS
On success, <<exp2>> and <<exp2f>> return the calculated value.
If the result underflows, the returned value is <<0>>. If the
result overflows, the returned value is <<HUGE_VAL>>. In
either case, <<errno>> is set to <<ERANGE>>.
PORTABILITY
ANSI C, POSIX.
*/
/*
* wrapper exp2(x)
*/
#include "fdlibm.h"
#if __OBSOLETE_MATH
#include <errno.h>
#include <math.h>
#ifndef _DOUBLE_IS_32BITS
#ifdef __STDC__
double exp2(double x) /* wrapper exp2 */
#else
double exp2(x) /* wrapper exp2 */
double x;
#endif
{
return pow(2.0, x);
}
#endif /* defined(_DOUBLE_IS_32BITS) */
#endif /* __OBSOLETE_MATH */
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