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      1 /* @(#)w_lgamma.c 5.1 93/09/24 */
      2 /*
      3  * ====================================================
      4  * Copyright (C) 1993 by Sun Microsystems, Inc. All rights reserved.
      5  *
      6  * Developed at SunPro, a Sun Microsystems, Inc. business.
      7  * Permission to use, copy, modify, and distribute this
      8  * software is freely granted, provided that this notice
      9  * is preserved.
     10  * ====================================================
     11  */
     12 
     13 #include <sys/cdefs.h>
     14 #if defined(LIBM_SCCS) && !defined(lint)
     15 __RCSID("$NetBSD: w_lgamma.c,v 1.10 2002/05/26 22:02:02 wiz Exp $");
     16 #endif
     17 
     18 /* double lgamma(double x)
     19  * Return the logarithm of the Gamma function of x.
     20  *
     21  * Method: call __ieee754_lgamma_r
     22  */
     23 
     24 #include "math.h"
     25 #include "math_private.h"
     26 
     27 double
     28 lgamma(double x)
     29 {
     30 #ifdef _IEEE_LIBM
     31 	return __ieee754_lgamma_r(x,&signgam);
     32 #else
     33         double y;
     34         y = __ieee754_lgamma_r(x,&signgam);
     35         if(_LIB_VERSION == _IEEE_) return y;
     36         if(!finite(y)&&finite(x)) {
     37             if(floor(x)==x&&x<=0.0)
     38                 return __kernel_standard(x,x,15); /* lgamma pole */
     39             else
     40                 return __kernel_standard(x,x,14); /* lgamma overflow */
     41         } else
     42             return y;
     43 #endif
     44 }
     45