mirror of
https://sourceware.org/git/glibc.git
synced 2024-11-22 21:10:07 +00:00
50 lines
1.3 KiB
C
50 lines
1.3 KiB
C
/* @(#)w_lgamma.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.
|
|
* ====================================================
|
|
*/
|
|
|
|
/* double lgamma(double x)
|
|
* Return the logarithm of the Gamma function of x.
|
|
*
|
|
* Method: call __ieee754_lgamma_r
|
|
*/
|
|
|
|
#include <math.h>
|
|
#include <math_private.h>
|
|
|
|
double
|
|
__lgamma(double x)
|
|
{
|
|
int local_signgam = 0;
|
|
double y = __ieee754_lgamma_r(x,
|
|
_LIB_VERSION != _ISOC_
|
|
/* ISO C99 does not define the
|
|
global variable. */
|
|
? &signgam
|
|
: &local_signgam);
|
|
if(__builtin_expect(!isfinite(y), 0)
|
|
&& isfinite(x) && _LIB_VERSION != _IEEE_)
|
|
return __kernel_standard(x, x,
|
|
__floor(x)==x&&x<=0.0
|
|
? 15 /* lgamma pole */
|
|
: 14); /* lgamma overflow */
|
|
|
|
return y;
|
|
}
|
|
weak_alias (__lgamma, lgamma)
|
|
strong_alias (__lgamma, __gamma)
|
|
weak_alias (__gamma, gamma)
|
|
#ifdef NO_LONG_DOUBLE
|
|
strong_alias (__lgamma, __lgammal)
|
|
weak_alias (__lgamma, lgammal)
|
|
strong_alias (__gamma, __gammal)
|
|
weak_alias (__gamma, gammal)
|
|
#endif
|