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/* @(#)wr_gamma.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.
* ====================================================
*/
/*
* wrapper double gamma_r(double x, int *signgamp)
*/
#include "fdlibm.h"
#include <errno.h>
#ifndef _DOUBLE_IS_32BITS
#ifdef __STDC__
double gamma_r(double x, int *signgamp) /* wrapper lgamma_r */
#else
double gamma_r(x,signgamp) /* wrapper lgamma_r */
double x; int *signgamp;
#endif
{
#ifdef _IEEE_LIBM
return __ieee754_gamma_r(x,signgamp);
#else
double y;
struct exception exc;
y = __ieee754_gamma_r(x,signgamp);
if(_LIB_VERSION == _IEEE_) return y;
if(!finite(y)&&finite(x)) {
#ifndef HUGE_VAL
#define HUGE_VAL inf
double inf = 0.0;
SET_HIGH_WORD(inf,0x7ff00000); /* set inf to infinite */
#endif
exc.name = "gamma";
exc.err = 0;
exc.arg1 = exc.arg2 = (double)x;
if (_LIB_VERSION == _SVID_)
exc.retval = HUGE;
else
exc.retval = HUGE_VAL;
if(floor(x)==x&&x<=0.0) {
/* gamma(-integer) or gamma(0) */
exc.type = SING;
if (_LIB_VERSION == _POSIX_)
errno = EDOM;
else if (!matherr(&exc)) {
errno = EDOM;
}
} else {
/* gamma(finite) overflow */
exc.type = OVERFLOW;
if (_LIB_VERSION == _POSIX_)
errno = ERANGE;
else if (!matherr(&exc)) {
errno = ERANGE;
}
}
if (exc.err != 0)
errno = exc.err;
return exc.retval;
} else
return y;
#endif
}
#endif /* defined(_DOUBLE_IS_32BITS) */
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