1/* w_jnl.c -- long double version of w_jn.c.
2 * Conversion to long double by Ulrich Drepper,
3 * Cygnus Support, drepper@cygnus.com.
4 */
5
6/*
7 * ====================================================
8 * Copyright (C) 1993 by Sun Microsystems, Inc. All rights reserved.
9 *
10 * Developed at SunPro, a Sun Microsystems, Inc. business.
11 * Permission to use, copy, modify, and distribute this
12 * software is freely granted, provided that this notice
13 * is preserved.
14 * ====================================================
15 */
16
17#if defined(LIBM_SCCS) && !defined(lint)
18static char rcsid[] = "$NetBSD: $";
19#endif
20
21/*
22 * wrapper jn(int n, double x), yn(int n, double x)
23 * floating point Bessel's function of the 1st and 2nd kind
24 * of order n
25 *
26 * Special cases:
27 * y0(0)=y1(0)=yn(n,0) = -inf with division by zero signal;
28 * y0(-ve)=y1(-ve)=yn(n,-ve) are NaN with invalid signal.
29 * Note 2. About jn(n,x), yn(n,x)
30 * For n=0, j0(x) is called,
31 * for n=1, j1(x) is called,
32 * for n<x, forward recursion us used starting
33 * from values of j0(x) and j1(x).
34 * for n>x, a continued fraction approximation to
35 * j(n,x)/j(n-1,x) is evaluated and then backward
36 * recursion is used starting from a supposed value
37 * for j(n,x). The resulting value of j(0,x) is
38 * compared with the actual value to correct the
39 * supposed value of j(n,x).
40 *
41 * yn(n,x) is similar in all respects, except
42 * that forward recursion is used for all
43 * values of n>1.
44 *
45 */
46
47#include <math.h>
48#include <math_private.h>
49
50long double __jnl(int n, long double x) /* wrapper jnl */
51{
52#ifdef _IEEE_LIBM
53 return __ieee754_jnl(n,x);
54#else
55 long double z;
56 z = __ieee754_jnl(n,x);
57 if (_LIB_VERSION == _IEEE_
58 || _LIB_VERSION == _POSIX_
59 || isnan(x))
60 return z;
61 if(fabsl(x)>X_TLOSS) {
62 return __kernel_standard_l((double)n,x,238); /* jn(|x|>X_TLOSS,n) */
63 } else
64 return z;
65#endif
66}
67weak_alias (__jnl, jnl)
68
69long double __ynl(int n, long double x) /* wrapper ynl */
70{
71#ifdef _IEEE_LIBM
72 return __ieee754_ynl(n,x);
73#else
74 long double z;
75 z = __ieee754_ynl(n,x);
76 if(_LIB_VERSION == _IEEE_ || isnan(x) ) return z;
77 if(x <= 0.0){
78 if(x==0.0)
79 /* d= -one/(x-x); */
80 return __kernel_standard_l((double)n,x,212);
81 else
82 /* d = zero/(x-x); */
83 return __kernel_standard_l((double)n,x,213);
84 }
85 if(x>X_TLOSS && _LIB_VERSION != _POSIX_) {
86 return __kernel_standard_l((double)n,x,239); /* yn(x>X_TLOSS,n) */
87 } else
88 return z;
89#endif
90}
91weak_alias (__ynl, ynl)
92