48 lines
1004 B
C
48 lines
1004 B
C
/* @(#)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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/* double gamma(double x)
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* Return the logarithm of the Gamma function of x or the Gamma function of x,
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* depending on the library mode.
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*/
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#include "fdlibm.h"
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#include <errno.h>
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#ifndef _DOUBLE_IS_32BITS
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#ifdef __STDC__
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double tgamma(double x)
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#else
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double tgamma(x)
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double x;
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#endif
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{
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double y;
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y = __ieee754_tgamma(x);
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#ifdef _IEEE_LIBM
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return y;
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#else
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if(_LIB_VERSION == _IEEE_) return y;
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if(!finite(y)) {
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if(x < 0.0 && floor(x)==x)
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errno = EDOM;
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else if (finite(x))
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errno = ERANGE;
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}
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return y;
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#endif
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}
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#endif /* defined(_DOUBLE_IS_32BITS) */
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