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authorSergey Cherkashin <4erkashin@list.ru>2017-10-03 15:26:34 +0300
committerWaldemar Brodkorb <wbx@uclibc-ng.org>2017-11-03 20:23:10 +0100
commitea38f4d89c9698895b1cf53a5946429dc1d8bbaa (patch)
treee05828ca1fedf55f104b837bc9c44215c2978e99 /libm/w_jnl.c
parent68de9946e914d8c30dcc6667a059ea59e5b74cac (diff)
math: add exception handling functionality
According to standards SVID and SYSV. Modified lgamma calling in case when 'signgam' variable should not be used. Signed-off-by: Waldemar Brodkorb <wbx@uclibc-ng.org>
Diffstat (limited to 'libm/w_jnl.c')
-rw-r--r--libm/w_jnl.c95
1 files changed, 95 insertions, 0 deletions
diff --git a/libm/w_jnl.c b/libm/w_jnl.c
new file mode 100644
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+/* w_jnl.c -- long double version of w_jn.c.
+ * Conversion to long double by Ulrich Drepper,
+ * Cygnus Support, drepper@cygnus.com.
+ */
+
+/*
+ * ====================================================
+ * 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: $";
+#endif
+
+/*
+ * wrapper jn(int n, double x), yn(int n, double x)
+ * floating point Bessel's function of the 1st and 2nd kind
+ * of order n
+ *
+ * Special cases:
+ * y0(0)=y1(0)=yn(n,0) = -inf with division by zero signal;
+ * y0(-ve)=y1(-ve)=yn(n,-ve) are NaN with invalid signal.
+ * Note 2. About jn(n,x), yn(n,x)
+ * For n=0, j0(x) is called,
+ * for n=1, j1(x) is called,
+ * for n<x, forward recursion us used starting
+ * from values of j0(x) and j1(x).
+ * for n>x, a continued fraction approximation to
+ * j(n,x)/j(n-1,x) is evaluated and then backward
+ * recursion is used starting from a supposed value
+ * for j(n,x). The resulting value of j(0,x) is
+ * compared with the actual value to correct the
+ * supposed value of j(n,x).
+ *
+ * yn(n,x) is similar in all respects, except
+ * that forward recursion is used for all
+ * values of n>1.
+ *
+ */
+
+#include <math.h>
+#include "math_private.h"
+
+#if !defined __NO_LONG_DOUBLE_MATH
+# ifndef __DO_XSI_MATH__
+long double
+jnl(int n, long double x) /* wrapper jnl */
+{
+# if __UCLIBC_HAS_FENV__
+ long double z;
+ z = (long double) __ieee754_jn(n, (double) x);
+ if (_LIB_VERSION == _IEEE_
+ || _LIB_VERSION == _POSIX_
+ || isnan(x))
+ return z;
+ if(fabsl(x)>X_TLOSS) {
+ return __kernel_standard_l((double)n,x,238); /* jn(|x|>X_TLOSS,n) */
+ } else
+ return z;
+# else
+ return (long double) __ieee754_jn(n, (double) x);
+# endif /* __UCLIBC_HAS_FENV__ */
+}
+
+long double
+ynl(int n, long double x) /* wrapper ynl */
+{
+# if __UCLIBC_HAS_FENV__
+ long double z;
+ z = (long double) __ieee754_yn(n,(double) x);
+ if(_LIB_VERSION == _IEEE_ || isnan(x) ) return z;
+ if(x <= 0.0){
+ if(x==0.0)
+ /* d= -one/(x-x); */
+ return __kernel_standard_l((double)n,x,212);
+ else
+ /* d = zero/(x-x); */
+ return __kernel_standard_l((double)n,x,213);
+ }
+ if(x>X_TLOSS && _LIB_VERSION != _POSIX_) {
+ return __kernel_standard_l((double)n,x,239); /* yn(x>X_TLOSS,n) */
+ } else
+ return z;
+# else
+ return (long double) __ieee754_yn(n,(double) x);
+# endif /* __UCLIBC_HAS_FENV__ */
+}
+# endif /* __DO_XSI_MATH__ */
+#endif /* __NO_LONG_DOUBLE_MATH */