X-Git-Url: https://git.donarmstrong.com/?p=rsem.git;a=blobdiff_plain;f=boost%2Fmath%2Fspecial_functions%2Fdetail%2Fbessel_y1.hpp;fp=boost%2Fmath%2Fspecial_functions%2Fdetail%2Fbessel_y1.hpp;h=8396f8fe1184a8a0b649a5a2cee58e3cbb476960;hp=0000000000000000000000000000000000000000;hb=2d71eb92104693ca9baa5a2e1c23eeca776d8fd3;hpb=da57529b92adbb7ae74a89861cb39fb35ac7c62d diff --git a/boost/math/special_functions/detail/bessel_y1.hpp b/boost/math/special_functions/detail/bessel_y1.hpp new file mode 100644 index 0000000..8396f8f --- /dev/null +++ b/boost/math/special_functions/detail/bessel_y1.hpp @@ -0,0 +1,196 @@ +// Copyright (c) 2006 Xiaogang Zhang +// Use, modification and distribution are subject to the +// Boost Software License, Version 1.0. (See accompanying file +// LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt) + +#ifndef BOOST_MATH_BESSEL_Y1_HPP +#define BOOST_MATH_BESSEL_Y1_HPP + +#ifdef _MSC_VER +#pragma once +#endif + +#include +#include +#include +#include +#include +#include + +// Bessel function of the second kind of order one +// x <= 8, minimax rational approximations on root-bracketing intervals +// x > 8, Hankel asymptotic expansion in Hart, Computer Approximations, 1968 + +namespace boost { namespace math { namespace detail{ + +template +T bessel_y1(T x, const Policy&); + +template +struct bessel_y1_initializer +{ + struct init + { + init() + { + do_init(); + } + static void do_init() + { + bessel_y1(T(1), Policy()); + } + void force_instantiate()const{} + }; + static const init initializer; + static void force_instantiate() + { + initializer.force_instantiate(); + } +}; + +template +const typename bessel_y1_initializer::init bessel_y1_initializer::initializer; + +template +T bessel_y1(T x, const Policy& pol) +{ + bessel_y1_initializer::force_instantiate(); + + static const T P1[] = { + static_cast(BOOST_MATH_BIG_CONSTANT(T, 64, 4.0535726612579544093e+13)), + static_cast(BOOST_MATH_BIG_CONSTANT(T, 64, 5.4708611716525426053e+12)), + static_cast(BOOST_MATH_BIG_CONSTANT(T, 64, -3.7595974497819597599e+11)), + static_cast(BOOST_MATH_BIG_CONSTANT(T, 64, 7.2144548214502560419e+09)), + static_cast(BOOST_MATH_BIG_CONSTANT(T, 64, -5.9157479997408395984e+07)), + static_cast(BOOST_MATH_BIG_CONSTANT(T, 64, 2.2157953222280260820e+05)), + static_cast(BOOST_MATH_BIG_CONSTANT(T, 64, -3.1714424660046133456e+02)), + }; + static const T Q1[] = { + static_cast(BOOST_MATH_BIG_CONSTANT(T, 64, 3.0737873921079286084e+14)), + static_cast(BOOST_MATH_BIG_CONSTANT(T, 64, 4.1272286200406461981e+12)), + static_cast(BOOST_MATH_BIG_CONSTANT(T, 64, 2.7800352738690585613e+10)), + static_cast(BOOST_MATH_BIG_CONSTANT(T, 64, 1.2250435122182963220e+08)), + static_cast(BOOST_MATH_BIG_CONSTANT(T, 64, 3.8136470753052572164e+05)), + static_cast(BOOST_MATH_BIG_CONSTANT(T, 64, 8.2079908168393867438e+02)), + static_cast(BOOST_MATH_BIG_CONSTANT(T, 64, 1.0)), + }; + static const T P2[] = { + static_cast(BOOST_MATH_BIG_CONSTANT(T, 64, 1.1514276357909013326e+19)), + static_cast(BOOST_MATH_BIG_CONSTANT(T, 64, -5.6808094574724204577e+18)), + static_cast(BOOST_MATH_BIG_CONSTANT(T, 64, -2.3638408497043134724e+16)), + static_cast(BOOST_MATH_BIG_CONSTANT(T, 64, 4.0686275289804744814e+15)), + static_cast(BOOST_MATH_BIG_CONSTANT(T, 64, -5.9530713129741981618e+13)), + static_cast(BOOST_MATH_BIG_CONSTANT(T, 64, 3.7453673962438488783e+11)), + static_cast(BOOST_MATH_BIG_CONSTANT(T, 64, -1.1957961912070617006e+09)), + static_cast(BOOST_MATH_BIG_CONSTANT(T, 64, 1.9153806858264202986e+06)), + static_cast(BOOST_MATH_BIG_CONSTANT(T, 64, -1.2337180442012953128e+03)), + }; + static const T Q2[] = { + static_cast(BOOST_MATH_BIG_CONSTANT(T, 64, 5.3321844313316185697e+20)), + static_cast(BOOST_MATH_BIG_CONSTANT(T, 64, 5.6968198822857178911e+18)), + static_cast(BOOST_MATH_BIG_CONSTANT(T, 64, 3.0837179548112881950e+16)), + static_cast(BOOST_MATH_BIG_CONSTANT(T, 64, 1.1187010065856971027e+14)), + static_cast(BOOST_MATH_BIG_CONSTANT(T, 64, 3.0221766852960403645e+11)), + static_cast(BOOST_MATH_BIG_CONSTANT(T, 64, 6.3550318087088919566e+08)), + static_cast(BOOST_MATH_BIG_CONSTANT(T, 64, 1.0453748201934079734e+06)), + static_cast(BOOST_MATH_BIG_CONSTANT(T, 64, 1.2855164849321609336e+03)), + static_cast(BOOST_MATH_BIG_CONSTANT(T, 64, 1.0)), + }; + static const T PC[] = { + static_cast(BOOST_MATH_BIG_CONSTANT(T, 64, -4.4357578167941278571e+06)), + static_cast(BOOST_MATH_BIG_CONSTANT(T, 64, -9.9422465050776411957e+06)), + static_cast(BOOST_MATH_BIG_CONSTANT(T, 64, -6.6033732483649391093e+06)), + static_cast(BOOST_MATH_BIG_CONSTANT(T, 64, -1.5235293511811373833e+06)), + static_cast(BOOST_MATH_BIG_CONSTANT(T, 64, -1.0982405543459346727e+05)), + static_cast(BOOST_MATH_BIG_CONSTANT(T, 64, -1.6116166443246101165e+03)), + static_cast(BOOST_MATH_BIG_CONSTANT(T, 64, 0.0)), + }; + static const T QC[] = { + static_cast(BOOST_MATH_BIG_CONSTANT(T, 64, -4.4357578167941278568e+06)), + static_cast(BOOST_MATH_BIG_CONSTANT(T, 64, -9.9341243899345856590e+06)), + static_cast(BOOST_MATH_BIG_CONSTANT(T, 64, -6.5853394797230870728e+06)), + static_cast(BOOST_MATH_BIG_CONSTANT(T, 64, -1.5118095066341608816e+06)), + static_cast(BOOST_MATH_BIG_CONSTANT(T, 64, -1.0726385991103820119e+05)), + static_cast(BOOST_MATH_BIG_CONSTANT(T, 64, -1.4550094401904961825e+03)), + static_cast(BOOST_MATH_BIG_CONSTANT(T, 64, 1.0)), + }; + static const T PS[] = { + static_cast(BOOST_MATH_BIG_CONSTANT(T, 64, 3.3220913409857223519e+04)), + static_cast(BOOST_MATH_BIG_CONSTANT(T, 64, 8.5145160675335701966e+04)), + static_cast(BOOST_MATH_BIG_CONSTANT(T, 64, 6.6178836581270835179e+04)), + static_cast(BOOST_MATH_BIG_CONSTANT(T, 64, 1.8494262873223866797e+04)), + static_cast(BOOST_MATH_BIG_CONSTANT(T, 64, 1.7063754290207680021e+03)), + static_cast(BOOST_MATH_BIG_CONSTANT(T, 64, 3.5265133846636032186e+01)), + static_cast(BOOST_MATH_BIG_CONSTANT(T, 64, 0.0)), + }; + static const T QS[] = { + static_cast(BOOST_MATH_BIG_CONSTANT(T, 64, 7.0871281941028743574e+05)), + static_cast(BOOST_MATH_BIG_CONSTANT(T, 64, 1.8194580422439972989e+06)), + static_cast(BOOST_MATH_BIG_CONSTANT(T, 64, 1.4194606696037208929e+06)), + static_cast(BOOST_MATH_BIG_CONSTANT(T, 64, 4.0029443582266975117e+05)), + static_cast(BOOST_MATH_BIG_CONSTANT(T, 64, 3.7890229745772202641e+04)), + static_cast(BOOST_MATH_BIG_CONSTANT(T, 64, 8.6383677696049909675e+02)), + static_cast(BOOST_MATH_BIG_CONSTANT(T, 64, 1.0)), + }; + static const T x1 = static_cast(BOOST_MATH_BIG_CONSTANT(T, 64, 2.1971413260310170351e+00)), + x2 = static_cast(BOOST_MATH_BIG_CONSTANT(T, 64, 5.4296810407941351328e+00)), + x11 = static_cast(BOOST_MATH_BIG_CONSTANT(T, 64, 5.620e+02)), + x12 = static_cast(BOOST_MATH_BIG_CONSTANT(T, 64, 1.8288260310170351490e-03)), + x21 = static_cast(BOOST_MATH_BIG_CONSTANT(T, 64, 1.3900e+03)), + x22 = static_cast(BOOST_MATH_BIG_CONSTANT(T, 64, -6.4592058648672279948e-06)) + ; + T value, factor, r, rc, rs; + + BOOST_MATH_STD_USING + using namespace boost::math::tools; + using namespace boost::math::constants; + + if (x <= 0) + { + return policies::raise_domain_error("bost::math::bessel_y1<%1%>(%1%,%1%)", + "Got x == %1%, but x must be > 0, complex result not supported.", x, pol); + } + if (x <= 4) // x in (0, 4] + { + T y = x * x; + T z = 2 * log(x/x1) * bessel_j1(x) / pi(); + r = evaluate_rational(P1, Q1, y); + factor = (x + x1) * ((x - x11/256) - x12) / x; + value = z + factor * r; + } + else if (x <= 8) // x in (4, 8] + { + T y = x * x; + T z = 2 * log(x/x2) * bessel_j1(x) / pi(); + r = evaluate_rational(P2, Q2, y); + factor = (x + x2) * ((x - x21/256) - x22) / x; + value = z + factor * r; + } + else // x in (8, \infty) + { + T y = 8 / x; + T y2 = y * y; + rc = evaluate_rational(PC, QC, y2); + rs = evaluate_rational(PS, QS, y2); + factor = 1 / (sqrt(x) * root_pi()); + // + // This code is really just: + // + // T z = x - 0.75f * pi(); + // value = factor * (rc * sin(z) + y * rs * cos(z)); + // + // But using the sin/cos addition rules, plus constants for sin/cos of 3PI/4 + // which then cancel out with corresponding terms in "factor". + // + T sx = sin(x); + T cx = cos(x); + value = factor * (y * rs * (sx - cx) - rc * (sx + cx)); + } + + return value; +} + +}}} // namespaces + +#endif // BOOST_MATH_BESSEL_Y1_HPP +