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Diffstat (limited to 'gcc-4.4.3/libstdc++-v3/include/tr1/legendre_function.tcc')
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1 files changed, 0 insertions, 305 deletions
diff --git a/gcc-4.4.3/libstdc++-v3/include/tr1/legendre_function.tcc b/gcc-4.4.3/libstdc++-v3/include/tr1/legendre_function.tcc deleted file mode 100644 index 8b59814da..000000000 --- a/gcc-4.4.3/libstdc++-v3/include/tr1/legendre_function.tcc +++ /dev/null @@ -1,305 +0,0 @@ -// Special functions -*- C++ -*- - -// Copyright (C) 2006, 2007, 2008, 2009 -// 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 3, 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. -// -// Under Section 7 of GPL version 3, you are granted additional -// permissions described in the GCC Runtime Library Exception, version -// 3.1, as published by the Free Software Foundation. - -// You should have received a copy of the GNU General Public License and -// a copy of the GCC Runtime Library Exception along with this program; -// see the files COPYING3 and COPYING.RUNTIME respectively. If not, see -// <http://www.gnu.org/licenses/>. - -/** @file tr1/legendre_function.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 8, pp. 331-341 -// (2) The Gnu Scientific Library, http://www.gnu.org/software/gsl -// (3) Numerical Recipes in C, by W. H. Press, S. A. Teukolsky, -// W. T. Vetterling, B. P. Flannery, Cambridge University Press (1992), -// 2nd ed, pp. 252-254 - -#ifndef _GLIBCXX_TR1_LEGENDRE_FUNCTION_TCC -#define _GLIBCXX_TR1_LEGENDRE_FUNCTION_TCC 1 - -#include "special_function_util.h" - -namespace std -{ -namespace tr1 -{ - - // [5.2] Special functions - - // Implementation-space details. - namespace __detail - { - - /** - * @brief Return the Legendre polynomial by recursion on order - * @f$ l @f$. - * - * The Legendre function of @f$ l @f$ and @f$ x @f$, - * @f$ P_l(x) @f$, is defined by: - * @f[ - * P_l(x) = \frac{1}{2^l l!}\frac{d^l}{dx^l}(x^2 - 1)^{l} - * @f] - * - * @param l The order of the Legendre polynomial. @f$l >= 0@f$. - * @param x The argument of the Legendre polynomial. @f$|x| <= 1@f$. - */ - template<typename _Tp> - _Tp - __poly_legendre_p(const unsigned int __l, const _Tp __x) - { - - if ((__x < _Tp(-1)) || (__x > _Tp(+1))) - std::__throw_domain_error(__N("Argument out of range" - " in __poly_legendre_p.")); - else if (__isnan(__x)) - return std::numeric_limits<_Tp>::quiet_NaN(); - else if (__x == +_Tp(1)) - return +_Tp(1); - else if (__x == -_Tp(1)) - return (__l % 2 == 1 ? -_Tp(1) : +_Tp(1)); - else - { - _Tp __p_lm2 = _Tp(1); - if (__l == 0) - return __p_lm2; - - _Tp __p_lm1 = __x; - if (__l == 1) - return __p_lm1; - - _Tp __p_l = 0; - for (unsigned int __ll = 2; __ll <= __l; ++__ll) - { - // This arrangement is supposed to be better for roundoff - // protection, Arfken, 2nd Ed, Eq 12.17a. - __p_l = _Tp(2) * __x * __p_lm1 - __p_lm2 - - (__x * __p_lm1 - __p_lm2) / _Tp(__ll); - __p_lm2 = __p_lm1; - __p_lm1 = __p_l; - } - - return __p_l; - } - } - - - /** - * @brief Return the associated Legendre function by recursion - * on @f$ l @f$. - * - * The associated Legendre function is derived from the Legendre function - * @f$ P_l(x) @f$ by the Rodrigues formula: - * @f[ - * P_l^m(x) = (1 - x^2)^{m/2}\frac{d^m}{dx^m}P_l(x) - * @f] - * - * @param l The order of the associated Legendre function. - * @f$ l >= 0 @f$. - * @param m The order of the associated Legendre function. - * @f$ m <= l @f$. - * @param x The argument of the associated Legendre function. - * @f$ |x| <= 1 @f$. - */ - template<typename _Tp> - _Tp - __assoc_legendre_p(const unsigned int __l, const unsigned int __m, - const _Tp __x) - { - - if (__x < _Tp(-1) || __x > _Tp(+1)) - std::__throw_domain_error(__N("Argument out of range" - " in __assoc_legendre_p.")); - else if (__m > __l) - std::__throw_domain_error(__N("Degree out of range" - " in __assoc_legendre_p.")); - else if (__isnan(__x)) - return std::numeric_limits<_Tp>::quiet_NaN(); - else if (__m == 0) - return __poly_legendre_p(__l, __x); - else - { - _Tp __p_mm = _Tp(1); - if (__m > 0) - { - // Two square roots seem more accurate more of the time - // than just one. - _Tp __root = std::sqrt(_Tp(1) - __x) * std::sqrt(_Tp(1) + __x); - _Tp __fact = _Tp(1); - for (unsigned int __i = 1; __i <= __m; ++__i) - { - __p_mm *= -__fact * __root; - __fact += _Tp(2); - } - } - if (__l == __m) - return __p_mm; - - _Tp __p_mp1m = _Tp(2 * __m + 1) * __x * __p_mm; - if (__l == __m + 1) - return __p_mp1m; - - _Tp __p_lm2m = __p_mm; - _Tp __P_lm1m = __p_mp1m; - _Tp __p_lm = _Tp(0); - for (unsigned int __j = __m + 2; __j <= __l; ++__j) - { - __p_lm = (_Tp(2 * __j - 1) * __x * __P_lm1m - - _Tp(__j + __m - 1) * __p_lm2m) / _Tp(__j - __m); - __p_lm2m = __P_lm1m; - __P_lm1m = __p_lm; - } - - return __p_lm; - } - } - - - /** - * @brief Return the spherical associated Legendre function. - * - * The spherical associated Legendre function of @f$ l @f$, @f$ m @f$, - * and @f$ \theta @f$ is defined as @f$ Y_l^m(\theta,0) @f$ where - * @f[ - * Y_l^m(\theta,\phi) = (-1)^m[\frac{(2l+1)}{4\pi} - * \frac{(l-m)!}{(l+m)!}] - * P_l^m(\cos\theta) \exp^{im\phi} - * @f] - * is the spherical harmonic function and @f$ P_l^m(x) @f$ is the - * associated Legendre function. - * - * This function differs from the associated Legendre function by - * argument (@f$x = \cos(\theta)@f$) and by a normalization factor - * but this factor is rather large for large @f$ l @f$ and @f$ m @f$ - * and so this function is stable for larger differences of @f$ l @f$ - * and @f$ m @f$. - * - * @param l The order of the spherical associated Legendre function. - * @f$ l >= 0 @f$. - * @param m The order of the spherical associated Legendre function. - * @f$ m <= l @f$. - * @param theta The radian angle argument of the spherical associated - * Legendre function. - */ - template <typename _Tp> - _Tp - __sph_legendre(const unsigned int __l, const unsigned int __m, - const _Tp __theta) - { - if (__isnan(__theta)) - return std::numeric_limits<_Tp>::quiet_NaN(); - - const _Tp __x = std::cos(__theta); - - if (__l < __m) - { - std::__throw_domain_error(__N("Bad argument " - "in __sph_legendre.")); - } - else if (__m == 0) - { - _Tp __P = __poly_legendre_p(__l, __x); - _Tp __fact = std::sqrt(_Tp(2 * __l + 1) - / (_Tp(4) * __numeric_constants<_Tp>::__pi())); - __P *= __fact; - return __P; - } - else if (__x == _Tp(1) || __x == -_Tp(1)) - { - // m > 0 here - return _Tp(0); - } - else - { - // m > 0 and |x| < 1 here - - // Starting value for recursion. - // Y_m^m(x) = sqrt( (2m+1)/(4pi m) gamma(m+1/2)/gamma(m) ) - // (-1)^m (1-x^2)^(m/2) / pi^(1/4) - const _Tp __sgn = ( __m % 2 == 1 ? -_Tp(1) : _Tp(1)); - const _Tp __y_mp1m_factor = __x * std::sqrt(_Tp(2 * __m + 3)); -#if _GLIBCXX_USE_C99_MATH_TR1 - const _Tp __lncirc = std::tr1::log1p(-__x * __x); -#else - const _Tp __lncirc = std::log(_Tp(1) - __x * __x); -#endif - // Gamma(m+1/2) / Gamma(m) -#if _GLIBCXX_USE_C99_MATH_TR1 - const _Tp __lnpoch = std::tr1::lgamma(_Tp(__m + _Tp(0.5L))) - - std::tr1::lgamma(_Tp(__m)); -#else - const _Tp __lnpoch = __log_gamma(_Tp(__m + _Tp(0.5L))) - - __log_gamma(_Tp(__m)); -#endif - const _Tp __lnpre_val = - -_Tp(0.25L) * __numeric_constants<_Tp>::__lnpi() - + _Tp(0.5L) * (__lnpoch + __m * __lncirc); - _Tp __sr = std::sqrt((_Tp(2) + _Tp(1) / __m) - / (_Tp(4) * __numeric_constants<_Tp>::__pi())); - _Tp __y_mm = __sgn * __sr * std::exp(__lnpre_val); - _Tp __y_mp1m = __y_mp1m_factor * __y_mm; - - if (__l == __m) - { - return __y_mm; - } - else if (__l == __m + 1) - { - return __y_mp1m; - } - else - { - _Tp __y_lm = _Tp(0); - - // Compute Y_l^m, l > m+1, upward recursion on l. - for ( int __ll = __m + 2; __ll <= __l; ++__ll) - { - const _Tp __rat1 = _Tp(__ll - __m) / _Tp(__ll + __m); - const _Tp __rat2 = _Tp(__ll - __m - 1) / _Tp(__ll + __m - 1); - const _Tp __fact1 = std::sqrt(__rat1 * _Tp(2 * __ll + 1) - * _Tp(2 * __ll - 1)); - const _Tp __fact2 = std::sqrt(__rat1 * __rat2 * _Tp(2 * __ll + 1) - / _Tp(2 * __ll - 3)); - __y_lm = (__x * __y_mp1m * __fact1 - - (__ll + __m - 1) * __y_mm * __fact2) / _Tp(__ll - __m); - __y_mm = __y_mp1m; - __y_mp1m = __y_lm; - } - - return __y_lm; - } - } - } - - } // namespace std::tr1::__detail -} -} - -#endif // _GLIBCXX_TR1_LEGENDRE_FUNCTION_TCC |