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/* @(#)w_gamma.c 5.1 93/09/24 */
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/*
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 * ====================================================
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 * Copyright (C) 1993 by Sun Microsystems, Inc. All rights reserved.
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 *
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 * Developed at SunPro, a Sun Microsystems, Inc. business.
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 * Permission to use, copy, modify, and distribute this
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 * software is freely granted, provided that this notice
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 * is preserved.
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 * ====================================================
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 */
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#ifndef lint
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static char rcsid[] = "$\Id: w_gamma.c,v 1.2 1995/05/30 05:51:04 rgrimes Exp $";
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#endif
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/* double gamma(double x)
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 * Return the logarithm of the Gamma function of x.
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 *
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 * Method: call gamma_r
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 */
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#include "math.h"
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#include "math_private.h"
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extern int signgam;
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#ifdef __STDC__
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        double gamma(double x)
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#else
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        double gamma(x)
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        double x;
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#endif
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{
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#ifdef _IEEE_LIBM
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        return __ieee754_gamma_r(x,&signgam);
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#else
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        double y;
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        y = __ieee754_gamma_r(x,&signgam);
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        if(_LIB_VERSION == _IEEE_) return y;
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        if(!finite(y)&&finite(x)) {
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            if(floor(x)==x&&x<=0.0)
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                return __kernel_standard(x,x,41); /* gamma pole */
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            else
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                return __kernel_standard(x,x,40); /* gamma overflow */
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        } else
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            return y;
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#endif
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}