mirror of
https://sourceware.org/git/glibc.git
synced 2024-11-14 01:00:07 +00:00
57 lines
1.4 KiB
C
57 lines
1.4 KiB
C
/* @(#)w_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.
|
|
* ====================================================
|
|
*/
|
|
|
|
#if defined(LIBM_SCCS) && !defined(lint)
|
|
static char rcsid[] = "$NetBSD: w_gamma.c,v 1.7 1995/11/20 22:06:43 jtc Exp $";
|
|
#endif
|
|
|
|
/* double gamma(double x)
|
|
* Return the logarithm of the Gamma function of x or the Gamma function of x,
|
|
* depending on the library mode.
|
|
*/
|
|
|
|
#include <math.h>
|
|
#include "math_private.h"
|
|
|
|
#ifdef __STDC__
|
|
double __tgamma(double x)
|
|
#else
|
|
double __tgamma(x)
|
|
double x;
|
|
#endif
|
|
{
|
|
double y;
|
|
int local_signgam;
|
|
y = __ieee754_gamma_r(x,&local_signgam);
|
|
if (local_signgam < 0) y = -y;
|
|
#ifdef _IEEE_LIBM
|
|
return y;
|
|
#else
|
|
if(_LIB_VERSION == _IEEE_) return y;
|
|
|
|
if(!__finite(y)&&__finite(x)) {
|
|
if (x == 0.0)
|
|
return __kernel_standard(x,x,50); /* tgamma pole */
|
|
else if(__floor(x)==x&&x<0.0)
|
|
return __kernel_standard(x,x,41); /* tgamma domain */
|
|
else
|
|
return __kernel_standard(x,x,40); /* tgamma overflow */
|
|
}
|
|
return y;
|
|
#endif
|
|
}
|
|
weak_alias (__tgamma, tgamma)
|
|
#ifdef NO_LONG_DOUBLE
|
|
strong_alias (__tgamma, __tgammal)
|
|
weak_alias (__tgamma, tgammal)
|
|
#endif
|