diff options
Diffstat (limited to 'libm/w_tgamma.c')
| -rw-r--r-- | libm/w_tgamma.c | 47 |
1 files changed, 47 insertions, 0 deletions
diff --git a/libm/w_tgamma.c b/libm/w_tgamma.c new file mode 100644 index 000000000..62b3c6275 --- /dev/null +++ b/libm/w_tgamma.c @@ -0,0 +1,47 @@ +/* @(#)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 "math.h" +#include "math_private.h" + +libm_hidden_proto(tgamma) +#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(floor(x)==x&&x<=0.0) + return __kernel_standard(x,x,41); /* tgamma pole */ + else + return __kernel_standard(x,x,40); /* tgamma overflow */ + } + return y; +#endif +} +libm_hidden_def(tgamma) |