support/fdlibm/w_lgamma.c
author Jan Vrany <jan.vrany@fit.cvut.cz>
Wed, 23 Jan 2013 12:31:33 +0000
branchdevelopment
changeset 1988 0fcf5a5dcb66
parent 1818 2e5ed72e7dfd
child 2380 9195eccdcbd9
permissions -rw-r--r--
Cleanup in JavaRelease: javaHome/jreHome/jdkHome.


/* @(#)w_lgamma.c 1.3 95/01/18 */
/*
 * ====================================================
 * Copyright (C) 1993 by Sun Microsystems, Inc. All rights reserved.
 *
 * Developed at SunSoft, 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 "fdlibm.h"

extern int signgam;

#ifdef __STDC__
	double lgamma(double x)
#else
	double lgamma(x)
	double x;
#endif
{
#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,15); /* lgamma pole */
            else
                return __kernel_standard(x,x,14); /* lgamma overflow */
        } else
            return y;
#endif
}