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-rw-r--r--math/w_jn.c127
1 files changed, 46 insertions, 81 deletions
diff --git a/math/w_jn.c b/math/w_jn.c
index 41ec8b32d4..36fb448163 100644
--- a/math/w_jn.c
+++ b/math/w_jn.c
@@ -1,98 +1,63 @@
-/* @(#)w_jn.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.
- * ====================================================
- */
+/* Copyright (C) 2011 Free Software Foundation, Inc.
+ This file is part of the GNU C Library.
+ Contributed by Ulrich Drepper <drepper@gmail.com>, 2011.
-#if defined(LIBM_SCCS) && !defined(lint)
-static char rcsid[] = "$NetBSD: w_jn.c,v 1.6 1995/05/10 20:49:19 jtc Exp $";
-#endif
+ The GNU C Library is free software; you can redistribute it and/or
+ modify it under the terms of the GNU Lesser General Public
+ License as published by the Free Software Foundation; either
+ version 2.1 of the License, or (at your option) any later version.
+
+ The GNU C Library is distributed in the hope that it will be useful,
+ but WITHOUT ANY WARRANTY; without even the implied warranty of
+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ Lesser General Public License for more details.
-/*
- * 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.
- *
- */
+ You should have received a copy of the GNU Lesser General Public
+ License along with the GNU C Library; if not, write to the Free
+ Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
+ 02111-1307 USA. */
+#include <fenv.h>
#include <math.h>
#include <math_private.h>
-#ifdef __STDC__
- double jn(int n, double x) /* wrapper jn */
-#else
- double jn(n,x) /* wrapper jn */
- double x; int n;
-#endif
+
+/* wrapper jn */
+double
+jn (int n, double x)
{
-#ifdef _IEEE_LIBM
- return __ieee754_jn(n,x);
-#else
- double z;
- z = __ieee754_jn(n,x);
- if(_LIB_VERSION == _IEEE_ || __isnan(x) ) return z;
- if(fabs(x)>X_TLOSS) {
- return __kernel_standard((double)n,x,38); /* jn(|x|>X_TLOSS,n) */
- } else
- return z;
-#endif
+ if (__builtin_expect (fabs (x) > X_TLOSS, 0) && _LIB_VERSION != _IEEE_)
+ /* jn(n,|x|>X_TLOSS) */
+ return __kernel_standard (n, x, 38);
+
+ return __ieee754_jn (n, x);
}
#ifdef NO_LONG_DOUBLE
strong_alias (jn, jnl)
#endif
-#ifdef __STDC__
- double yn(int n, double x) /* wrapper yn */
-#else
- double yn(n,x) /* wrapper yn */
- double x; int n;
-#endif
+/* wrapper yn */
+double
+yn (int n, double x)
{
-#ifdef _IEEE_LIBM
- return __ieee754_yn(n,x);
-#else
- double z;
- z = __ieee754_yn(n,x);
- if(_LIB_VERSION == _IEEE_ || __isnan(x) ) return z;
- if(x <= 0.0){
- if(x==0.0)
- /* d= -one/(x-x); */
- return __kernel_standard((double)n,x,12);
- else
- /* d = zero/(x-x); */
- return __kernel_standard((double)n,x,13);
- }
- if(x>X_TLOSS) {
- return __kernel_standard((double)n,x,39); /* yn(x>X_TLOSS,n) */
- } else
- return z;
-#endif
+ if (__builtin_expect (x <= 0.0 || x > X_TLOSS, 0) && _LIB_VERSION != _IEEE_)
+ {
+ if (x < 0.0)
+ {
+ /* d = zero/(x-x) */
+ feraiseexcept (FE_INVALID);
+ return __kernel_standard (n, x, 13);
+ }
+ else if (x == 0.0)
+ /* d = -one/(x-x) */
+ return __kernel_standard (n, x, 12);
+ else
+ /* yn(n,x>X_TLOSS) */
+ return __kernel_standard (n, x, 39);
+ }
+
+ return __ieee754_yn (n, x);
}
#ifdef NO_LONG_DOUBLE
strong_alias (yn, ynl)