newlib-cygwin/newlib/libm/math/wf_gamma.c

61 lines
1.3 KiB
C

/* wf_gamma.c -- float version of w_gamma.c.
* Conversion to float by Ian Lance Taylor, Cygnus Support, ian@cygnus.com.
*/
/*
* ====================================================
* 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.
* ====================================================
*
*/
#include "fdlibm.h"
#include <reent.h>
#include <errno.h>
#ifdef __STDC__
float gammaf(float x)
#else
float gammaf(x)
float x;
#endif
{
#ifdef _IEEE_LIBM
return __ieee754_gammaf_r(x,&(_REENT_SIGNGAM(_REENT)));
#else
float y;
y = __ieee754_gammaf_r(x,&(_REENT_SIGNGAM(_REENT)));
if(_LIB_VERSION == _IEEE_) return y;
if(!finitef(y)&&finitef(x)) {
if(floorf(x)==x&&x<=0.0f) {
/* gammaf(-integer) or gammaf(0) */
errno = EDOM;
} else {
/* gammaf(finite) overflow */
errno = ERANGE;
}
return HUGE_VALF;
} else
return y;
#endif
}
#ifdef _DOUBLE_IS_32BITS
#ifdef __STDC__
double gamma(double x)
#else
double gamma(x)
double x;
#endif
{
return (double) gammaf((float) x);
}
#endif /* defined(_DOUBLE_IS_32BITS) */