/* @(#)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. * ==================================================== */ #include <sys/cdefs.h> #if defined(LIBM_SCCS) && !defined(lint) __RCSID("$NetBSD: w_gamma.c,v 1.11 2002/05/26 22:02:00 wiz Exp $"); #endif /* double gamma(double x) * Return the logarithm of the Gamma function of x. * * Method: call gamma_r */ #include "math.h" #include "math_private.h" double gamma(double x) { #ifdef _IEEE_LIBM return __ieee754_lgamma_r(x,&signgam); #else double y; y = __ieee754_lgamma_r(x,&signgam); if(_LIB_VERSION == _IEEE_) return y; if(!finite(y)&&finite(x)) { if(floor(x)==x&&x<=0.0) return __kernel_standard(x,x,41); /* gamma pole */ else return __kernel_standard(x,x,40); /* gamma overflow */ } else return y; #endif } |