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-rw-r--r--libm/w_lgamma.c49
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diff --git a/libm/w_lgamma.c b/libm/w_lgamma.c
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+/* @(#)w_lgamma.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_lgamma.c,v 1.6 1995/05/10 20:49:24 jtc Exp $";
+#endif
+
+/* double lgamma(double x)
+ * Return the logarithm of the Gamma function of x.
+ *
+ * Method: call __ieee754_lgamma_r
+ */
+
+#include "math.h"
+#include "math_private.h"
+
+extern int signgam;
+
+#ifdef __STDC__
+ double lgamma(double x)
+#else
+ double lgamma(x)
+ double x;
+#endif
+{
+#ifdef _IEEE_LIBM
+ return __ieee754_lgamma_r(x,&signgam);
+#else
+ double y;
+ y = __ieee754_lgamma_r(x,&signgam);
+ if(_LIB_VERSION == _IEEE_) return y;
+ if(!finite(y)&&finite(x)) {
+ if(floor(x)==x&&x<=0.0)
+ return __kernel_standard(x,x,15); /* lgamma pole */
+ else
+ return __kernel_standard(x,x,14); /* lgamma overflow */
+ } else
+ return y;
+#endif
+}