diff options
author | bkoz <bkoz@138bc75d-0d04-0410-961f-82ee72b054a4> | 2007-03-16 10:35:16 +0000 |
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committer | bkoz <bkoz@138bc75d-0d04-0410-961f-82ee72b054a4> | 2007-03-16 10:35:16 +0000 |
commit | b34f60accb416680ed11789c89296e3c68ed68f1 (patch) | |
tree | decac71c7af454edb119868a1763aff3b7c70e56 /libstdc++-v3/include/tr1/poly_laguerre.tcc | |
parent | 15ec875c733b473953eae3637f13665dffb0589b (diff) | |
download | ppe42-gcc-b34f60accb416680ed11789c89296e3c68ed68f1.tar.gz ppe42-gcc-b34f60accb416680ed11789c89296e3c68ed68f1.zip |
2007-03-16 Benjamin Kosnik <bkoz@redhat.com>
* testsuite/lib/dg-options.exp (dg-require-c-std): New.
* testsuite/lib/libstdc++.exp (check_v3_target_c_std): New. Check to
see if _GLIBCXX_USE_C99_MATH is active.
* testsuite/tr1/5_numerical_facilities/special_functions/
08_cyl_bessel_i/check_nan.cc: Use dg-require-c-std.
* testsuite/tr1/5_numerical_facilities/special_functions/
17_hyperg/check_nan.cc: Same.
* testsuite/tr1/5_numerical_facilities/special_functions/
13_ellint_2/check_nan.cc: Same.
* testsuite/tr1/5_numerical_facilities/special_functions/
20_riemann_zeta/check_nan.cc: Same.
* testsuite/tr1/5_numerical_facilities/special_functions/
01_assoc_laguerre/check_nan.cc: Same.
* testsuite/tr1/5_numerical_facilities/special_functions/
02_assoc_legendre/check_nan.cc: Same.
* testsuite/tr1/5_numerical_facilities/special_functions/
22_sph_legendre/check_nan.cc: Same.
* testsuite/tr1/5_numerical_facilities/special_functions/
10_cyl_bessel_k/check_nan.cc: Same.
* testsuite/tr1/5_numerical_facilities/special_functions/
09_cyl_bessel_j/check_nan.cc: Same.
* testsuite/tr1/5_numerical_facilities/special_functions/
21_sph_bessel/check_nan.cc: Same.
* testsuite/tr1/5_numerical_facilities/special_functions/
07_conf_hyperg/check_nan.cc: Same.
* testsuite/tr1/5_numerical_facilities/special_functions/
16_hermite/check_nan.cc: Same.
* testsuite/tr1/5_numerical_facilities/special_functions/
12_ellint_1/check_nan.cc: Same.
* testsuite/tr1/5_numerical_facilities/special_functions/
05_comp_ellint_2/check_nan.cc: Same.
* testsuite/tr1/5_numerical_facilities/special_functions/
18_laguerre/check_nan.cc: Same.
* testsuite/tr1/5_numerical_facilities/special_functions/
14_ellint_3/check_nan.cc: Same.
* testsuite/tr1/5_numerical_facilities/special_functions/
04_comp_ellint_1/check_nan.cc: Same.
* testsuite/tr1/5_numerical_facilities/special_functions/
06_comp_ellint_3/check_nan.cc: Same.
* testsuite/tr1/5_numerical_facilities/special_functions/
19_legendre/check_nan.cc: Same.
* testsuite/tr1/5_numerical_facilities/special_functions/
03_beta/check_nan.cc: Same.
* testsuite/tr1/5_numerical_facilities/special_functions/
11_cyl_neumann/check_nan.cc: Same.
* testsuite/tr1/5_numerical_facilities/special_functions/
15_expint/check_nan.cc: Same.
* testsuite/tr1/5_numerical_facilities/special_functions/
23_sph_neumann/check_nan.cc: Same.
* include/tr1/poly_laguerre.tcc (__poly_laguerre): Don't check if
unsigned int can be a NaN.
2007-03-16 Edward M. Smith-Rowland <3dw4rd@verizon.net>
* docs/html/ext/tr1.html : Marked tr1 math special functions done.
* docs/html/faq/index.html : Ditto.
* include/Makefile.in : Added new special function header files.
* include/Makefile.am : Ditto.
* include/tr1/common.h : Added type promotion routines for three
and four args.
* include/tr1/special_function_util.h: New.
* include/tr1/bessel_function.tcc: New.
* include/tr1/beta_function.tcc: New.
* include/tr1/ell_integral.tcc: New.
* include/tr1/exp_integral.tcc: New.
* include/tr1/gamma.tcc: New.
* include/tr1/hypergeometric.tcc: New.
* include/tr1/legendre_function.tcc: New.
* include/tr1/modified_bessel_func.tcc: New.
* include/tr1/poly_hermite.tcc: New.
* include/tr1/poly_laguerre.tcc: New.
* include/tr1/riemann_zeta.tcc: New.
* include/tr1/cmath : Included tr1 math special functions.
* include/tr1/math.h : Ditto.
* testsuite/tr1/5_numerical_facilities/special_functions/
testcase.h: New.
* testsuite/tr1/5_numerical_facilities/special_functions/
01_assoc_laguerre/compile.cc: New.
* testsuite/tr1/5_numerical_facilities/special_functions/
01_assoc_laguerre/check_nan.cc: New.
* testsuite/tr1/5_numerical_facilities/special_functions/
01_assoc_laguerre/check_value.cc: New.
* testsuite/tr1/5_numerical_facilities/special_functions/
01_assoc_laguerre/compile_2.cc: New.
* testsuite/tr1/5_numerical_facilities/special_functions/
02_assoc_legendre/compile.cc: New.
* testsuite/tr1/5_numerical_facilities/special_functions/
02_assoc_legendre/check_nan.cc: New.
* testsuite/tr1/5_numerical_facilities/special_functions/
02_assoc_legendre/check_value.cc: New.
* testsuite/tr1/5_numerical_facilities/special_functions/
02_assoc_legendre/compile_2.cc: New.
* testsuite/tr1/5_numerical_facilities/special_functions/03_beta/
compile.cc: New.
* testsuite/tr1/5_numerical_facilities/special_functions/03_beta/
check_nan.cc: New.
* testsuite/tr1/5_numerical_facilities/special_functions/03_beta/
check_value.cc: New.
* testsuite/tr1/5_numerical_facilities/special_functions/03_beta/
compile_2.cc: New.
* testsuite/tr1/5_numerical_facilities/special_functions/
04_comp_ellint_1/compile.cc: New.
* testsuite/tr1/5_numerical_facilities/special_functions/
04_comp_ellint_1/check_nan.cc: New.
* testsuite/tr1/5_numerical_facilities/special_functions/
04_comp_ellint_1/check_value.cc: New.
* testsuite/tr1/5_numerical_facilities/special_functions/
04_comp_ellint_1/compile_2.cc: New.
* testsuite/tr1/5_numerical_facilities/special_functions/
05_comp_ellint_2/compile.cc: New.
* testsuite/tr1/5_numerical_facilities/special_functions/
05_comp_ellint_2/check_nan.cc: New.
* testsuite/tr1/5_numerical_facilities/special_functions/
05_comp_ellint_2/check_value.cc: New.
* testsuite/tr1/5_numerical_facilities/special_functions/
05_comp_ellint_2/compile_2.cc: New.
* testsuite/tr1/5_numerical_facilities/special_functions/
06_comp_ellint_3/compile.cc: New.
* testsuite/tr1/5_numerical_facilities/special_functions/
06_comp_ellint_3/check_nan.cc: New.
* testsuite/tr1/5_numerical_facilities/special_functions/
06_comp_ellint_3/check_value.cc: New.
* testsuite/tr1/5_numerical_facilities/special_functions/
06_comp_ellint_3/compile_2.cc: New.
* testsuite/tr1/5_numerical_facilities/special_functions/
07_conf_hyperg/compile.cc: New.
* testsuite/tr1/5_numerical_facilities/special_functions/
07_conf_hyperg/check_nan.cc: New.
* testsuite/tr1/5_numerical_facilities/special_functions/
07_conf_hyperg/check_value.cc: New.
* testsuite/tr1/5_numerical_facilities/special_functions/
07_conf_hyperg/compile_2.cc: New.
* testsuite/tr1/5_numerical_facilities/special_functions/
08_cyl_bessel_i/compile.cc: New.
* testsuite/tr1/5_numerical_facilities/special_functions/
08_cyl_bessel_i/check_nan.cc: New.
* testsuite/tr1/5_numerical_facilities/special_functions/
08_cyl_bessel_i/check_value.cc: New.
* testsuite/tr1/5_numerical_facilities/special_functions/
08_cyl_bessel_i/compile_2.cc: New.
* testsuite/tr1/5_numerical_facilities/special_functions/
09_cyl_bessel_j/compile.cc: New.
* testsuite/tr1/5_numerical_facilities/special_functions/
09_cyl_bessel_j/check_nan.cc: New.
* testsuite/tr1/5_numerical_facilities/special_functions/
09_cyl_bessel_j/check_value.cc: New.
* testsuite/tr1/5_numerical_facilities/special_functions/
09_cyl_bessel_j/compile_2.cc: New.
* testsuite/tr1/5_numerical_facilities/special_functions/
10_cyl_bessel_k/compile.cc: New.
* testsuite/tr1/5_numerical_facilities/special_functions/
10_cyl_bessel_k/check_nan.cc: New.
* testsuite/tr1/5_numerical_facilities/special_functions/
10_cyl_bessel_k/check_value.cc: New.
* testsuite/tr1/5_numerical_facilities/special_functions/
10_cyl_bessel_k/compile_2.cc: New.
* testsuite/tr1/5_numerical_facilities/special_functions/
11_cyl_neumann/compile.cc: New.
* testsuite/tr1/5_numerical_facilities/special_functions/
11_cyl_neumann/check_nan.cc: New.
* testsuite/tr1/5_numerical_facilities/special_functions/
11_cyl_neumann/check_value.cc: New.
* testsuite/tr1/5_numerical_facilities/special_functions/
11_cyl_neumann/compile_2.cc: New.
* testsuite/tr1/5_numerical_facilities/special_functions/12_ellint_1/
compile.cc: New.
* testsuite/tr1/5_numerical_facilities/special_functions/12_ellint_1/
check_nan.cc: New.
* testsuite/tr1/5_numerical_facilities/special_functions/12_ellint_1/
check_value.cc: New.
* testsuite/tr1/5_numerical_facilities/special_functions/12_ellint_1/
compile_2.cc: New.
* testsuite/tr1/5_numerical_facilities/special_functions/13_ellint_2/
compile.cc: New.
* testsuite/tr1/5_numerical_facilities/special_functions/13_ellint_2/
check_nan.cc: New.
* testsuite/tr1/5_numerical_facilities/special_functions/13_ellint_2/
check_value.cc: New.
* testsuite/tr1/5_numerical_facilities/special_functions/13_ellint_2/
compile_2.cc: New.
* testsuite/tr1/5_numerical_facilities/special_functions/14_ellint_3/
compile.cc: New.
* testsuite/tr1/5_numerical_facilities/special_functions/14_ellint_3/
check_nan.cc: New.
* testsuite/tr1/5_numerical_facilities/special_functions/14_ellint_3/
check_value.cc: New.
* testsuite/tr1/5_numerical_facilities/special_functions/14_ellint_3/
compile_2.cc: New.
* testsuite/tr1/5_numerical_facilities/special_functions/15_expint/
check_value_neg.cc: New.
* testsuite/tr1/5_numerical_facilities/special_functions/15_expint/
compile.cc: New.
* testsuite/tr1/5_numerical_facilities/special_functions/15_expint/
check_nan.cc: New.
* testsuite/tr1/5_numerical_facilities/special_functions/15_expint/
compile_2.cc: New.
* testsuite/tr1/5_numerical_facilities/special_functions/15_expint/
check_value_pos.cc: New.
* testsuite/tr1/5_numerical_facilities/special_functions/16_hermite/
compile.cc: New.
* testsuite/tr1/5_numerical_facilities/special_functions/16_hermite/
check_nan.cc: New.
* testsuite/tr1/5_numerical_facilities/special_functions/16_hermite/
compile_2.cc: New.
* testsuite/tr1/5_numerical_facilities/special_functions/17_hyperg/
compile.cc: New.
* testsuite/tr1/5_numerical_facilities/special_functions/17_hyperg/
check_nan.cc: New.
* testsuite/tr1/5_numerical_facilities/special_functions/17_hyperg/
check_value.cc: New.
* testsuite/tr1/5_numerical_facilities/special_functions/17_hyperg/
compile_2.cc: New.
* testsuite/tr1/5_numerical_facilities/special_functions/18_laguerre/
compile.cc: New.
* testsuite/tr1/5_numerical_facilities/special_functions/18_laguerre/
check_nan.cc: New.
* testsuite/tr1/5_numerical_facilities/special_functions/18_laguerre/
check_value.cc: New.
* testsuite/tr1/5_numerical_facilities/special_functions/18_laguerre/
compile_2.cc: New.
* testsuite/tr1/5_numerical_facilities/special_functions/19_legendre/
compile.cc: New.
* testsuite/tr1/5_numerical_facilities/special_functions/19_legendre/
check_nan.cc: New.
* testsuite/tr1/5_numerical_facilities/special_functions/19_legendre/
check_value.cc: New.
* testsuite/tr1/5_numerical_facilities/special_functions/19_legendre/
compile_2.cc: New.
* testsuite/tr1/5_numerical_facilities/special_functions/
20_riemann_zeta/check_value_neg.cc: New.
* testsuite/tr1/5_numerical_facilities/special_functions/
20_riemann_zeta/compile.cc: New.
* testsuite/tr1/5_numerical_facilities/special_functions/
20_riemann_zeta/check_nan.cc: New.
* testsuite/tr1/5_numerical_facilities/special_functions/
20_riemann_zeta/compile_2.cc: New.
* testsuite/tr1/5_numerical_facilities/special_functions/
20_riemann_zeta/check_value_pos.cc: New.
* testsuite/tr1/5_numerical_facilities/special_functions/
21_sph_bessel/compile.cc: New.
* testsuite/tr1/5_numerical_facilities/special_functions/
21_sph_bessel/check_nan.cc: New.
* testsuite/tr1/5_numerical_facilities/special_functions/
21_sph_bessel/check_value.cc: New.
* testsuite/tr1/5_numerical_facilities/special_functions/
21_sph_bessel/compile_2.cc: New.
* testsuite/tr1/5_numerical_facilities/special_functions/
22_sph_legendre/compile.cc: New.
* testsuite/tr1/5_numerical_facilities/special_functions/
22_sph_legendre/check_nan.cc: New.
* testsuite/tr1/5_numerical_facilities/special_functions/
22_sph_legendre/check_value.cc: New.
* testsuite/tr1/5_numerical_facilities/special_functions/
22_sph_legendre/compile_2.cc: New.
* testsuite/tr1/5_numerical_facilities/special_functions/
23_sph_neumann/compile.cc: New.
* testsuite/tr1/5_numerical_facilities/special_functions/
23_sph_neumann/check_nan.cc: New.
* testsuite/tr1/5_numerical_facilities/special_functions/
23_sph_neumann/check_value.cc: New.
* testsuite/tr1/5_numerical_facilities/special_functions/
23_sph_neumann/ compile_2.cc: New.
git-svn-id: svn+ssh://gcc.gnu.org/svn/gcc/trunk@122986 138bc75d-0d04-0410-961f-82ee72b054a4
Diffstat (limited to 'libstdc++-v3/include/tr1/poly_laguerre.tcc')
-rw-r--r-- | libstdc++-v3/include/tr1/poly_laguerre.tcc | 342 |
1 files changed, 342 insertions, 0 deletions
diff --git a/libstdc++-v3/include/tr1/poly_laguerre.tcc b/libstdc++-v3/include/tr1/poly_laguerre.tcc new file mode 100644 index 00000000000..5200cab79c0 --- /dev/null +++ b/libstdc++-v3/include/tr1/poly_laguerre.tcc @@ -0,0 +1,342 @@ +// Special functions -*- C++ -*- + +// Copyright (C) 2006-2007 +// Free Software Foundation, Inc. +// +// This file is part of the GNU ISO C++ Library. This library is free +// software; you can redistribute it and/or modify it under the +// terms of the GNU General Public License as published by the +// Free Software Foundation; either version 2, or (at your option) +// any later version. +// +// This 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 General Public License for more details. +// +// You should have received a copy of the GNU General Public License along +// with this library; see the file COPYING. If not, write to the Free +// Software Foundation, 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, +// USA. +// +// As a special exception, you may use this file as part of a free software +// library without restriction. Specifically, if other files instantiate +// templates or use macros or inline functions from this file, or you compile +// this file and link it with other files to produce an executable, this +// file does not by itself cause the resulting executable to be covered by +// the GNU General Public License. This exception does not however +// invalidate any other reasons why the executable file might be covered by +// the GNU General Public License. + +/** @file tr1/poly_laguerre.tcc + * This is an internal header file, included by other library headers. + * You should not attempt to use it directly. + */ + +// +// ISO C++ 14882 TR1: 5.2 Special functions +// + +// Written by Edward Smith-Rowland based on: +// (1) Handbook of Mathematical Functions, +// Ed. Milton Abramowitz and Irene A. Stegun, +// Dover Publications, +// Section 13, pp. 509-510, Section 22 pp. 773-802 +// (2) The Gnu Scientific Library, http://www.gnu.org/software/gsl + +#ifndef _TR1_POLY_LAGUERRE_TCC +#define _TR1_POLY_LAGUERRE_TCC 1 + +namespace std +{ +_GLIBCXX_BEGIN_NAMESPACE(_GLIBCXX_TR1) + + // [5.2] Special functions + + /** + * @ingroup tr1_math_spec_func + * @{ + */ + + // + // Implementation-space details. + // + namespace __detail + { + + + /** + * @brief This routine returns the associated Laguerre polynomial + * of order @f$ n @f$, degree @f$ \alpha @f$ for large n. + * Abramowitz & Stegun, 13.5.21 + * + * @param __n The order of the Laguerre function. + * @param __alpha The degree of the Laguerre function. + * @param __x The argument of the Laguerre function. + * @return The value of the Laguerre function of order n, + * degree @f$ \alpha @f$, and argument x. + * + * This is from the GNU Scientific Library. + */ + template<typename _Tpa, typename _Tp> + _Tp + __poly_laguerre_large_n(const unsigned __n, const _Tpa __alpha, + const _Tp __x) + { + const _Tp __a = -_Tp(__n); + const _Tp __b = _Tp(__alpha) + _Tp(1); + const _Tp __eta = _Tp(2) * __b - _Tp(4) * __a; + const _Tp __cos2th = __x / __eta; + const _Tp __sin2th = _Tp(1) - __cos2th; + const _Tp __th = std::acos(std::sqrt(__cos2th)); + const _Tp __pre_h = __numeric_constants<_Tp>::__pi_2() + * __numeric_constants<_Tp>::__pi_2() + * __eta * __eta * __cos2th * __sin2th; + +#if _GLIBCXX_USE_C99_MATH_TR1 + const _Tp __lg_b = std::_GLIBCXX_TR1::lgamma(_Tp(__n) + __b); + const _Tp __lnfact = std::_GLIBCXX_TR1::lgamma(_Tp(__n + 1)); +#else + const _Tp __lg_b = __log_gamma(_Tp(__n) + __b); + const _Tp __lnfact = __log_gamma(_Tp(__n + 1)); +#endif + + _Tp __pre_term1 = _Tp(0.5L) * (_Tp(1) - __b) + * std::log(_Tp(0.25L) * __x * __eta); + _Tp __pre_term2 = _Tp(0.25L) * std::log(__pre_h); + _Tp __lnpre = __lg_b - __lnfact + _Tp(0.5L) * __x + + __pre_term1 - __pre_term2; + _Tp __ser_term1 = std::sin(__a * __numeric_constants<_Tp>::__pi()); + _Tp __ser_term2 = std::sin(_Tp(0.25L) * __eta + * (_Tp(2) * __th + - std::sin(_Tp(2) * __th)) + + __numeric_constants<_Tp>::__pi_4()); + _Tp __ser = __ser_term1 + __ser_term2; + + return std::exp(__lnpre) * __ser; + } + + + /** + * @brief Evaluate the polynomial based on the confluent hypergeometric + * function in a safe way, with no restriction on the arguments. + * + * The associated Laguerre function is defined by + * @f[ + * L_n^\alpha(x) = \frac{(\alpha + 1)_n}{n!} + * _1F_1(-n; \alpha + 1; x) + * @f] + * where @f$ (\alpha)_n @f$ is the Pochhammer symbol and + * @f$ _1F_1(a; c; x) @f$ is the confluent hypergeometric function. + * + * This function assumes x != 0. + * + * This is from the GNU Scientific Library. + */ + template<typename _Tpa, typename _Tp> + _Tp + __poly_laguerre_hyperg(const unsigned int __n, const _Tpa __alpha, const _Tp __x) + { + const _Tp __b = _Tp(__alpha) + _Tp(1); + const _Tp __mx = -__x; + const _Tp __tc_sgn = (__x < _Tp(0) ? _Tp(1) + : ((__n % 2 == 1) ? -_Tp(1) : _Tp(1))); + // Get |x|^n/n! + _Tp __tc = _Tp(1); + const _Tp __ax = std::abs(__x); + for (unsigned int __k = 1; __k <= __n; ++__k) + __tc *= (__ax / __k); + + _Tp __term = __tc * __tc_sgn; + _Tp __sum = __term; + for (int __k = int(__n) - 1; __k >= 0; --__k) + { + __term *= ((__b + _Tp(__k)) / _Tp(int(__n) - __k)) + * _Tp(__k + 1) / __mx; + __sum += __term; + } + + return __sum; + } + + + /** + * @brief This routine returns the associated Laguerre polynomial + * of order @f$ n @f$, degree @f$ \alpha @f$: @f$ L_n^\alpha(x) @f$ + * by recursion. + * + * The associated Laguerre function is defined by + * @f[ + * L_n^\alpha(x) = \frac{(\alpha + 1)_n}{n!} + * _1F_1(-n; \alpha + 1; x) + * @f] + * where @f$ (\alpha)_n @f$ is the Pochhammer symbol and + * @f$ _1F_1(a; c; x) @f$ is the confluent hypergeometric function. + * + * The associated Laguerre polynomial is defined for integral + * @f$ \alpha = m @f$ by: + * @f[ + * L_n^m(x) = (-1)^m \frac{d^m}{dx^m} L_{n + m}(x) + * @f] + * where the Laguerre polynomial is defined by: + * @f[ + * L_n(x) = \frac{e^x}{n!} \frac{d^n}{dx^n} (x^ne^{-x}) + * @f] + * + * @param __n The order of the Laguerre function. + * @param __alpha The degree of the Laguerre function. + * @param __x The argument of the Laguerre function. + * @return The value of the Laguerre function of order n, + * degree @f$ \alpha @f$, and argument x. + */ + template<typename _Tpa, typename _Tp> + _Tp + __poly_laguerre_recursion(const unsigned int __n, + const _Tpa __alpha, const _Tp __x) + { + // Compute l_0. + _Tp __l_0 = _Tp(1); + if (__n == 0) + return __l_0; + + // Compute l_1^alpha. + _Tp __l_1 = -__x + _Tp(1) + _Tp(__alpha); + if (__n == 1) + return __l_1; + + // Compute l_n^alpha by recursion on n. + _Tp __l_n2 = __l_0; + _Tp __l_n1 = __l_1; + _Tp __l_n = _Tp(0); + for (unsigned int __nn = 2; __nn <= __n; ++__nn) + { + __l_n = (_Tp(2 * __nn - 1) + _Tp(__alpha) - __x) + * __l_n1 / _Tp(__nn) + - (_Tp(__nn - 1) + _Tp(__alpha)) * __l_n2 / _Tp(__nn); + __l_n2 = __l_n1; + __l_n1 = __l_n; + } + + return __l_n; + } + + + /** + * @brief This routine returns the associated Laguerre polynomial + * of order n, degree @f$ \alpha @f$: @f$ L_n^alpha(x) @f$. + * + * The associated Laguerre function is defined by + * @f[ + * L_n^\alpha(x) = \frac{(\alpha + 1)_n}{n!} + * _1F_1(-n; \alpha + 1; x) + * @f] + * where @f$ (\alpha)_n @f$ is the Pochhammer symbol and + * @f$ _1F_1(a; c; x) @f$ is the confluent hypergeometric function. + * + * The associated Laguerre polynomial is defined for integral + * @f$ \alpha = m @f$ by: + * @f[ + * L_n^m(x) = (-1)^m \frac{d^m}{dx^m} L_{n + m}(x) + * @f] + * where the Laguerre polynomial is defined by: + * @f[ + * L_n(x) = \frac{e^x}{n!} \frac{d^n}{dx^n} (x^ne^{-x}) + * @f] + * + * @param __n The order of the Laguerre function. + * @param __alpha The degree of the Laguerre function. + * @param __x The argument of the Laguerre function. + * @return The value of the Laguerre function of order n, + * degree @f$ \alpha @f$, and argument x. + */ + template<typename _Tpa, typename _Tp> + inline _Tp + __poly_laguerre(const unsigned int __n, const _Tpa __alpha, + const _Tp __x) + { + if (__x < _Tp(0)) + std::__throw_domain_error(__N("Negative argument " + "in __poly_laguerre.")); + // Return NaN on NaN input. + else if (__isnan(__x)) + return std::numeric_limits<_Tp>::quiet_NaN(); + else if (__n == 0) + return _Tp(1); + else if (__n == 1) + return _Tp(1) + _Tp(__alpha) - __x; + else if (__x == _Tp(0)) + { + _Tp __prod = _Tp(__alpha) + _Tp(1); + for (unsigned int __k = 2; __k <= __n; ++__k) + __prod *= (_Tp(__alpha) + _Tp(__k)) / _Tp(__k); + return __prod; + } + else if (__n > 10000000 && _Tp(__alpha) > -_Tp(1) + && __x < _Tp(2) * (_Tp(__alpha) + _Tp(1)) + _Tp(4 * __n)) + return __poly_laguerre_large_n(__n, __alpha, __x); + else if (_Tp(__alpha) >= _Tp(0) + || (__x > _Tp(0) && _Tp(__alpha) < -_Tp(__n + 1))) + return __poly_laguerre_recursion(__n, __alpha, __x); + else + return __poly_laguerre_hyperg(__n, __alpha, __x); + } + + + /** + * @brief This routine returns the associated Laguerre polynomial + * of order n, degree m: @f$ L_n^m @f$. + * + * The associated Laguerre polynomial is defined for integral + * @f$ \alpha = m @f$ by: + * @f[ + * L_n^m(x) = (-1)^m \frac{d^m}{dx^m} L_{n + m}(x) + * @f] + * where the Laguerre polynomial is defined by: + * @f[ + * L_n(x) = \frac{e^x}{n!} \frac{d^n}{dx^n} (x^ne^{-x}) + * @f] + * + * @param __n The order of the Laguerre polynomial. + * @param __m The degree of the Laguerre polynomial. + * @param __x The argument of the Laguerre polynomial. + * @return The value of the associated Laguerre polynomial of order n, + * degree m, and argument x. + */ + template<typename _Tp> + inline _Tp + __assoc_laguerre(const unsigned int __n, const unsigned int __m, + const _Tp __x) + { + return __poly_laguerre<unsigned int, _Tp>(__n, __m, __x); + } + + + /** + * @brief This routine returns the associated Laguerre polynomial + * of order n: @f$ L_n(x) @f$. + * + * The Laguerre polynomial is defined by: + * @f[ + * L_n(x) = \frac{e^x}{n!} \frac{d^n}{dx^n} (x^ne^{-x}) + * @f] + * + * @param __n The order of the Laguerre polynomial. + * @param __x The argument of the Laguerre polynomial. + * @return The value of the Laguerre polynomial of order n + * and argument x. + */ + template<typename _Tp> + inline _Tp + __laguerre(const unsigned int __n, const _Tp __x) + { + return __poly_laguerre<unsigned int, _Tp>(__n, 0, __x); + } + + } // namespace std::tr1::__detail + + /* @} */ // group tr1_math_spec_func + +_GLIBCXX_END_NAMESPACE +} + +#endif // _TR1_POLY_LAGUERRE_TCC |