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authorBernhard Reutner-Fischer <rep.dot.nop@gmail.com>2008-09-25 19:07:18 +0000
committerBernhard Reutner-Fischer <rep.dot.nop@gmail.com>2008-09-25 19:07:18 +0000
commitc7a58c2edadb8fce84ab2f8b129a87eb19bdc485 (patch)
treeb0ce15fb6eb16bbfe34612a21ffc16709d397b33 /libm/w_tgamma.c
parentc8d8b6d30a29b353637cd1c7379402bff2481b79 (diff)
- add some more math functions (patch from gentoo/solar)
Diffstat (limited to 'libm/w_tgamma.c')
-rw-r--r--libm/w_tgamma.c47
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)