/* 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 nx, 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 #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 defined(__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 defined(__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 */