61 lines
1.6 KiB
C
61 lines
1.6 KiB
C
/* @(#)w_lgamma.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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#if defined(LIBM_SCCS) && !defined(lint)
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static char rcsid[] = "$NetBSD: w_lgamma.c,v 1.6 1995/05/10 20:49:24 jtc Exp $";
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#endif
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/* double lgamma(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 __ieee754_lgamma_r
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*/
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#include "math.h"
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#include "math_private.h"
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#ifdef __STDC__
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double __lgamma(double x)
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#else
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double __lgamma(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_lgamma_r(x,&signgam);
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#else
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double y;
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int local_signgam;
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y = __ieee754_lgamma_r(x,&local_signgam);
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if (_LIB_VERSION != _ISOC_)
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/* ISO C99 does not define the global variable. */
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signgam = local_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,15); /* lgamma pole */
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else
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return __kernel_standard(x,x,14); /* lgamma overflow */
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} else
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return y;
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#endif
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}
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weak_alias (__lgamma, lgamma)
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strong_alias (__lgamma, __gamma)
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weak_alias (__gamma, gamma)
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#ifdef NO_LONG_DOUBLE
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strong_alias (__lgamma, __lgammal)
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weak_alias (__lgamma, lgammal)
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strong_alias (__gamma, __gammal)
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weak_alias (__gamma, gammal)
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#endif
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