diff options
Diffstat (limited to 'math/w_tgamma_compat.c')
| -rw-r--r-- | math/w_tgamma_compat.c | 46 |
1 files changed, 46 insertions, 0 deletions
diff --git a/math/w_tgamma_compat.c b/math/w_tgamma_compat.c new file mode 100644 index 0000000000..99b60298ca --- /dev/null +++ b/math/w_tgamma_compat.c @@ -0,0 +1,46 @@ +/* @(#)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. + * ==================================================== + */ + +/* 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 <errno.h> +#include <math.h> +#include <math_private.h> + +double +__tgamma(double x) +{ + int local_signgam; + double y = __ieee754_gamma_r(x,&local_signgam); + + if(__glibc_unlikely (!isfinite (y) || y == 0) + && (isfinite (x) || (isinf (x) && x < 0.0)) + && _LIB_VERSION != _IEEE_) { + 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 if (y == 0) + __set_errno (ERANGE); /* tgamma underflow */ + else + return __kernel_standard(x,x,40); /* tgamma overflow */ + } + return local_signgam < 0 ? -y : y; +} +weak_alias (__tgamma, tgamma) +#ifdef NO_LONG_DOUBLE +strong_alias (__tgamma, __tgammal) +weak_alias (__tgamma, tgammal) +#endif |