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Diffstat (limited to 'math/w_tgamma.c')
| -rw-r--r-- | math/w_tgamma.c | 56 |
1 files changed, 56 insertions, 0 deletions
diff --git a/math/w_tgamma.c b/math/w_tgamma.c new file mode 100644 index 0000000000..3ce6e77b49 --- /dev/null +++ b/math/w_tgamma.c @@ -0,0 +1,56 @@ +/* @(#)w_gamma.c 5.1 93/09/24 */ +/* + * ==================================================== + * Copyright (C) 1993 by Sun Microsystems, Inc. All rights reserved. + * + * Developed at SunPro, a Sun Microsystems, Inc. business. + * Permission to use, copy, modify, and distribute this + * software is freely granted, provided that this notice + * is preserved. + * ==================================================== + */ + +#if defined(LIBM_SCCS) && !defined(lint) +static char rcsid[] = "$NetBSD: w_gamma.c,v 1.7 1995/11/20 22:06:43 jtc Exp $"; +#endif + +/* double gamma(double x) + * Return the logarithm of the Gamma function of x or the Gamma function of x, + * depending on the library mode. + */ + +#include <math.h> +#include "math_private.h" + +#ifdef __STDC__ + double __tgamma(double x) +#else + double __tgamma(x) + double x; +#endif +{ + double y; + int local_signgam; + y = __ieee754_gamma_r(x,&local_signgam); + if (local_signgam < 0) y = -y; +#ifdef _IEEE_LIBM + return y; +#else + if(_LIB_VERSION == _IEEE_) return y; + + if(!__finite(y)&&__finite(x)) { + if (x == 0.0) + return __kernel_standard(x,x,50); /* tgamma pole */ + else if(__floor(x)==x&&x<0.0) + return __kernel_standard(x,x,41); /* tgamma domain */ + else + return __kernel_standard(x,x,40); /* tgamma overflow */ + } + return y; +#endif +} +weak_alias (__tgamma, tgamma) +#ifdef NO_LONG_DOUBLE +strong_alias (__tgamma, __tgammal) +weak_alias (__tgamma, tgammal) +#endif |