| // Copyright John Maddock 2007. | |
| // 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_EXPINT_HPP | |
| #define BOOST_MATH_EXPINT_HPP | |
| #ifdef _MSC_VER | |
| #pragma once | |
| #endif | |
| #include <boost/math/tools/precision.hpp> | |
| #include <boost/math/tools/promotion.hpp> | |
| #include <boost/math/tools/fraction.hpp> | |
| #include <boost/math/tools/series.hpp> | |
| #include <boost/math/policies/error_handling.hpp> | |
| #include <boost/math/special_functions/digamma.hpp> | |
| #include <boost/math/special_functions/log1p.hpp> | |
| #include <boost/math/special_functions/pow.hpp> | |
| namespace boost{ namespace math{ | |
| template <class T, class Policy> | |
| inline typename tools::promote_args<T>::type | |
| expint(unsigned n, T z, const Policy& /*pol*/); | |
| namespace detail{ | |
| template <class T> | |
| inline T expint_1_rational(const T& z, const mpl::int_<0>&) | |
| { | |
| // this function is never actually called | |
| BOOST_ASSERT(0); | |
| return z; | |
| } | |
| template <class T> | |
| T expint_1_rational(const T& z, const mpl::int_<53>&) | |
| { | |
| BOOST_MATH_STD_USING | |
| T result; | |
| if(z <= 1) | |
| { | |
| // Maximum Deviation Found: 2.006e-18 | |
| // Expected Error Term: 2.006e-18 | |
| // Max error found at double precision: 2.760e-17 | |
| static const T Y = 0.66373538970947265625F; | |
| static const T P[6] = { | |
| 0.0865197248079397976498L, | |
| 0.0320913665303559189999L, | |
| -0.245088216639761496153L, | |
| -0.0368031736257943745142L, | |
| -0.00399167106081113256961L, | |
| -0.000111507792921197858394L | |
| }; | |
| static const T Q[6] = { | |
| 1L, | |
| 0.37091387659397013215L, | |
| 0.056770677104207528384L, | |
| 0.00427347600017103698101L, | |
| 0.000131049900798434683324L, | |
| -0.528611029520217142048e-6L | |
| }; | |
| result = tools::evaluate_polynomial(P, z) | |
| / tools::evaluate_polynomial(Q, z); | |
| result += z - log(z) - Y; | |
| } | |
| else if(z < -boost::math::tools::log_min_value<T>()) | |
| { | |
| // Maximum Deviation Found (interpolated): 1.444e-17 | |
| // Max error found at double precision: 3.119e-17 | |
| static const T P[11] = { | |
| -0.121013190657725568138e-18L, | |
| -0.999999999999998811143L, | |
| -43.3058660811817946037L, | |
| -724.581482791462469795L, | |
| -6046.8250112711035463L, | |
| -27182.6254466733970467L, | |
| -66598.2652345418633509L, | |
| -86273.1567711649528784L, | |
| -54844.4587226402067411L, | |
| -14751.4895786128450662L, | |
| -1185.45720315201027667L | |
| }; | |
| static const T Q[12] = { | |
| 1L, | |
| 45.3058660811801465927L, | |
| 809.193214954550328455L, | |
| 7417.37624454689546708L, | |
| 38129.5594484818471461L, | |
| 113057.05869159631492L, | |
| 192104.047790227984431L, | |
| 180329.498380501819718L, | |
| 86722.3403467334749201L, | |
| 18455.4124737722049515L, | |
| 1229.20784182403048905L, | |
| -0.776491285282330997549L | |
| }; | |
| T recip = 1 / z; | |
| result = 1 + tools::evaluate_polynomial(P, recip) | |
| / tools::evaluate_polynomial(Q, recip); | |
| result *= exp(-z) * recip; | |
| } | |
| else | |
| { | |
| result = 0; | |
| } | |
| return result; | |
| } | |
| template <class T> | |
| T expint_1_rational(const T& z, const mpl::int_<64>&) | |
| { | |
| BOOST_MATH_STD_USING | |
| T result; | |
| if(z <= 1) | |
| { | |
| // Maximum Deviation Found: 3.807e-20 | |
| // Expected Error Term: 3.807e-20 | |
| // Max error found at long double precision: 6.249e-20 | |
| static const T Y = 0.66373538970947265625F; | |
| static const T P[6] = { | |
| 0.0865197248079397956816L, | |
| 0.0275114007037026844633L, | |
| -0.246594388074877139824L, | |
| -0.0237624819878732642231L, | |
| -0.00259113319641673986276L, | |
| 0.30853660894346057053e-4L | |
| }; | |
| static const T Q[7] = { | |
| 1L, | |
| 0.317978365797784100273L, | |
| 0.0393622602554758722511L, | |
| 0.00204062029115966323229L, | |
| 0.732512107100088047854e-5L, | |
| -0.202872781770207871975e-5L, | |
| 0.52779248094603709945e-7L | |
| }; | |
| result = tools::evaluate_polynomial(P, z) | |
| / tools::evaluate_polynomial(Q, z); | |
| result += z - log(z) - Y; | |
| } | |
| else if(z < -boost::math::tools::log_min_value<T>()) | |
| { | |
| // Maximum Deviation Found (interpolated): 2.220e-20 | |
| // Max error found at long double precision: 1.346e-19 | |
| static const T P[14] = { | |
| -0.534401189080684443046e-23L, | |
| -0.999999999999999999905L, | |
| -62.1517806091379402505L, | |
| -1568.45688271895145277L, | |
| -21015.3431990874009619L, | |
| -164333.011755931661949L, | |
| -777917.270775426696103L, | |
| -2244188.56195255112937L, | |
| -3888702.98145335643429L, | |
| -3909822.65621952648353L, | |
| -2149033.9538897398457L, | |
| -584705.537139793925189L, | |
| -65815.2605361889477244L, | |
| -2038.82870680427258038L | |
| }; | |
| static const T Q[14] = { | |
| 1L, | |
| 64.1517806091379399478L, | |
| 1690.76044393722763785L, | |
| 24035.9534033068949426L, | |
| 203679.998633572361706L, | |
| 1074661.58459976978285L, | |
| 3586552.65020899358773L, | |
| 7552186.84989547621411L, | |
| 9853333.79353054111434L, | |
| 7689642.74550683631258L, | |
| 3385553.35146759180739L, | |
| 763218.072732396428725L, | |
| 73930.2995984054930821L, | |
| 2063.86994219629165937L | |
| }; | |
| T recip = 1 / z; | |
| result = 1 + tools::evaluate_polynomial(P, recip) | |
| / tools::evaluate_polynomial(Q, recip); | |
| result *= exp(-z) * recip; | |
| } | |
| else | |
| { | |
| result = 0; | |
| } | |
| return result; | |
| } | |
| template <class T> | |
| T expint_1_rational(const T& z, const mpl::int_<113>&) | |
| { | |
| BOOST_MATH_STD_USING | |
| T result; | |
| if(z <= 1) | |
| { | |
| // Maximum Deviation Found: 2.477e-35 | |
| // Expected Error Term: 2.477e-35 | |
| // Max error found at long double precision: 6.810e-35 | |
| static const T Y = 0.66373538970947265625F; | |
| static const T P[10] = { | |
| 0.0865197248079397956434879099175975937L, | |
| 0.0369066175910795772830865304506087759L, | |
| -0.24272036838415474665971599314725545L, | |
| -0.0502166331248948515282379137550178307L, | |
| -0.00768384138547489410285101483730424919L, | |
| -0.000612574337702109683505224915484717162L, | |
| -0.380207107950635046971492617061708534e-4L, | |
| -0.136528159460768830763009294683628406e-5L, | |
| -0.346839106212658259681029388908658618e-7L, | |
| -0.340500302777838063940402160594523429e-9L | |
| }; | |
| static const T Q[10] = { | |
| 1L, | |
| 0.426568827778942588160423015589537302L, | |
| 0.0841384046470893490592450881447510148L, | |
| 0.0100557215850668029618957359471132995L, | |
| 0.000799334870474627021737357294799839363L, | |
| 0.434452090903862735242423068552687688e-4L, | |
| 0.15829674748799079874182885081231252e-5L, | |
| 0.354406206738023762100882270033082198e-7L, | |
| 0.369373328141051577845488477377890236e-9L, | |
| -0.274149801370933606409282434677600112e-12L | |
| }; | |
| result = tools::evaluate_polynomial(P, z) | |
| / tools::evaluate_polynomial(Q, z); | |
| result += z - log(z) - Y; | |
| } | |
| else if(z <= 4) | |
| { | |
| // Max error in interpolated form: 5.614e-35 | |
| // Max error found at long double precision: 7.979e-35 | |
| static const T Y = 0.70190334320068359375F; | |
| static const T P[17] = { | |
| 0.298096656795020369955077350585959794L, | |
| 12.9314045995266142913135497455971247L, | |
| 226.144334921582637462526628217345501L, | |
| 2070.83670924261732722117682067381405L, | |
| 10715.1115684330959908244769731347186L, | |
| 30728.7876355542048019664777316053311L, | |
| 38520.6078609349855436936232610875297L, | |
| -27606.0780981527583168728339620565165L, | |
| -169026.485055785605958655247592604835L, | |
| -254361.919204983608659069868035092282L, | |
| -195765.706874132267953259272028679935L, | |
| -83352.6826013533205474990119962408675L, | |
| -19251.6828496869586415162597993050194L, | |
| -2226.64251774578542836725386936102339L, | |
| -109.009437301400845902228611986479816L, | |
| -1.51492042209561411434644938098833499L | |
| }; | |
| static const T Q[16] = { | |
| 1L, | |
| 46.734521442032505570517810766704587L, | |
| 908.694714348462269000247450058595655L, | |
| 9701.76053033673927362784882748513195L, | |
| 63254.2815292641314236625196594947774L, | |
| 265115.641285880437335106541757711092L, | |
| 732707.841188071900498536533086567735L, | |
| 1348514.02492635723327306628712057794L, | |
| 1649986.81455283047769673308781585991L, | |
| 1326000.828522976970116271208812099L, | |
| 683643.09490612171772350481773951341L, | |
| 217640.505137263607952365685653352229L, | |
| 40288.3467237411710881822569476155485L, | |
| 3932.89353979531632559232883283175754L, | |
| 169.845369689596739824177412096477219L, | |
| 2.17607292280092201170768401876895354L | |
| }; | |
| T recip = 1 / z; | |
| result = Y + tools::evaluate_polynomial(P, recip) | |
| / tools::evaluate_polynomial(Q, recip); | |
| result *= exp(-z) * recip; | |
| } | |
| else if(z < -boost::math::tools::log_min_value<T>()) | |
| { | |
| // Max error in interpolated form: 4.413e-35 | |
| // Max error found at long double precision: 8.928e-35 | |
| static const T P[19] = { | |
| -0.559148411832951463689610809550083986e-40L, | |
| -0.999999999999999999999999999999999997L, | |
| -166.542326331163836642960118190147367L, | |
| -12204.639128796330005065904675153652L, | |
| -520807.069767086071806275022036146855L, | |
| -14435981.5242137970691490903863125326L, | |
| -274574945.737064301247496460758654196L, | |
| -3691611582.99810039356254671781473079L, | |
| -35622515944.8255047299363690814678763L, | |
| -248040014774.502043161750715548451142L, | |
| -1243190389769.53458416330946622607913L, | |
| -4441730126135.54739052731990368425339L, | |
| -11117043181899.7388524310281751971366L, | |
| -18976497615396.9717776601813519498961L, | |
| -21237496819711.1011661104761906067131L, | |
| -14695899122092.5161620333466757812848L, | |
| -5737221535080.30569711574295785864903L, | |
| -1077042281708.42654526404581272546244L, | |
| -68028222642.1941480871395695677675137L | |
| }; | |
| static const T Q[20] = { | |
| 1L, | |
| 168.542326331163836642960118190147311L, | |
| 12535.7237814586576783518249115343619L, | |
| 544891.263372016404143120911148640627L, | |
| 15454474.7241010258634446523045237762L, | |
| 302495899.896629522673410325891717381L, | |
| 4215565948.38886507646911672693270307L, | |
| 42552409471.7951815668506556705733344L, | |
| 313592377066.753173979584098301610186L, | |
| 1688763640223.4541980740597514904542L, | |
| 6610992294901.59589748057620192145704L, | |
| 18601637235659.6059890851321772682606L, | |
| 36944278231087.2571020964163402941583L, | |
| 50425858518481.7497071917028793820058L, | |
| 45508060902865.0899967797848815980644L, | |
| 25649955002765.3817331501988304758142L, | |
| 8259575619094.6518520988612711292331L, | |
| 1299981487496.12607474362723586264515L, | |
| 70242279152.8241187845178443118302693L, | |
| -37633302.9409263839042721539363416685L | |
| }; | |
| T recip = 1 / z; | |
| result = 1 + tools::evaluate_polynomial(P, recip) | |
| / tools::evaluate_polynomial(Q, recip); | |
| result *= exp(-z) * recip; | |
| } | |
| else | |
| { | |
| result = 0; | |
| } | |
| return result; | |
| } | |
| template <class T> | |
| struct expint_fraction | |
| { | |
| typedef std::pair<T,T> result_type; | |
| expint_fraction(unsigned n_, T z_) : b(n_ + z_), i(-1), n(n_){} | |
| std::pair<T,T> operator()() | |
| { | |
| std::pair<T,T> result = std::make_pair(-static_cast<T>((i+1) * (n+i)), b); | |
| b += 2; | |
| ++i; | |
| return result; | |
| } | |
| private: | |
| T b; | |
| int i; | |
| unsigned n; | |
| }; | |
| template <class T, class Policy> | |
| inline T expint_as_fraction(unsigned n, T z, const Policy& pol) | |
| { | |
| BOOST_MATH_STD_USING | |
| BOOST_MATH_INSTRUMENT_VARIABLE(z) | |
| boost::uintmax_t max_iter = policies::get_max_series_iterations<Policy>(); | |
| expint_fraction<T> f(n, z); | |
| T result = tools::continued_fraction_b( | |
| f, | |
| boost::math::policies::get_epsilon<T, Policy>(), | |
| max_iter); | |
| policies::check_series_iterations("boost::math::expint_continued_fraction<%1%>(unsigned,%1%)", max_iter, pol); | |
| BOOST_MATH_INSTRUMENT_VARIABLE(result) | |
| BOOST_MATH_INSTRUMENT_VARIABLE(max_iter) | |
| result = exp(-z) / result; | |
| BOOST_MATH_INSTRUMENT_VARIABLE(result) | |
| return result; | |
| } | |
| template <class T> | |
| struct expint_series | |
| { | |
| typedef T result_type; | |
| expint_series(unsigned k_, T z_, T x_k_, T denom_, T fact_) | |
| : k(k_), z(z_), x_k(x_k_), denom(denom_), fact(fact_){} | |
| T operator()() | |
| { | |
| x_k *= -z; | |
| denom += 1; | |
| fact *= ++k; | |
| return x_k / (denom * fact); | |
| } | |
| private: | |
| unsigned k; | |
| T z; | |
| T x_k; | |
| T denom; | |
| T fact; | |
| }; | |
| template <class T, class Policy> | |
| inline T expint_as_series(unsigned n, T z, const Policy& pol) | |
| { | |
| BOOST_MATH_STD_USING | |
| boost::uintmax_t max_iter = policies::get_max_series_iterations<Policy>(); | |
| BOOST_MATH_INSTRUMENT_VARIABLE(z) | |
| T result = 0; | |
| T x_k = -1; | |
| T denom = T(1) - n; | |
| T fact = 1; | |
| unsigned k = 0; | |
| for(; k < n - 1;) | |
| { | |
| result += x_k / (denom * fact); | |
| denom += 1; | |
| x_k *= -z; | |
| fact *= ++k; | |
| } | |
| BOOST_MATH_INSTRUMENT_VARIABLE(result) | |
| result += pow(-z, static_cast<T>(n - 1)) | |
| * (boost::math::digamma(static_cast<T>(n)) - log(z)) / fact; | |
| BOOST_MATH_INSTRUMENT_VARIABLE(result) | |
| expint_series<T> s(k, z, x_k, denom, fact); | |
| result = tools::sum_series(s, policies::get_epsilon<T, Policy>(), max_iter, result); | |
| policies::check_series_iterations("boost::math::expint_series<%1%>(unsigned,%1%)", max_iter, pol); | |
| BOOST_MATH_INSTRUMENT_VARIABLE(result) | |
| BOOST_MATH_INSTRUMENT_VARIABLE(max_iter) | |
| return result; | |
| } | |
| template <class T, class Policy, class Tag> | |
| T expint_imp(unsigned n, T z, const Policy& pol, const Tag& tag) | |
| { | |
| BOOST_MATH_STD_USING | |
| static const char* function = "boost::math::expint<%1%>(unsigned, %1%)"; | |
| if(z < 0) | |
| return policies::raise_domain_error<T>(function, "Function requires z >= 0 but got %1%.", z, pol); | |
| if(z == 0) | |
| return n == 1 ? policies::raise_overflow_error<T>(function, 0, pol) : T(1 / (static_cast<T>(n - 1))); | |
| T result; | |
| bool f; | |
| if(n < 3) | |
| { | |
| f = z < 0.5; | |
| } | |
| else | |
| { | |
| f = z < (static_cast<T>(n - 2) / static_cast<T>(n - 1)); | |
| } | |
| #ifdef BOOST_MSVC | |
| # pragma warning(push) | |
| # pragma warning(disable:4127) // conditional expression is constant | |
| #endif | |
| if(n == 0) | |
| result = exp(-z) / z; | |
| else if((n == 1) && (Tag::value)) | |
| { | |
| result = expint_1_rational(z, tag); | |
| } | |
| else if(f) | |
| result = expint_as_series(n, z, pol); | |
| else | |
| result = expint_as_fraction(n, z, pol); | |
| #ifdef BOOST_MSVC | |
| # pragma warning(pop) | |
| #endif | |
| return result; | |
| } | |
| template <class T> | |
| struct expint_i_series | |
| { | |
| typedef T result_type; | |
| expint_i_series(T z_) : k(0), z_k(1), z(z_){} | |
| T operator()() | |
| { | |
| z_k *= z / ++k; | |
| return z_k / k; | |
| } | |
| private: | |
| unsigned k; | |
| T z_k; | |
| T z; | |
| }; | |
| template <class T, class Policy> | |
| T expint_i_as_series(T z, const Policy& pol) | |
| { | |
| BOOST_MATH_STD_USING | |
| T result = log(z); // (log(z) - log(1 / z)) / 2; | |
| result += constants::euler<T>(); | |
| expint_i_series<T> s(z); | |
| boost::uintmax_t max_iter = policies::get_max_series_iterations<Policy>(); | |
| result = tools::sum_series(s, policies::get_epsilon<T, Policy>(), max_iter, result); | |
| policies::check_series_iterations("boost::math::expint_i_series<%1%>(%1%)", max_iter, pol); | |
| return result; | |
| } | |
| template <class T, class Policy, class Tag> | |
| T expint_i_imp(T z, const Policy& pol, const Tag& tag) | |
| { | |
| static const char* function = "boost::math::expint<%1%>(%1%)"; | |
| if(z < 0) | |
| return -expint_imp(1, T(-z), pol, tag); | |
| if(z == 0) | |
| return -policies::raise_overflow_error<T>(function, 0, pol); | |
| return expint_i_as_series(z, pol); | |
| } | |
| template <class T, class Policy> | |
| T expint_i_imp(T z, const Policy& pol, const mpl::int_<53>& tag) | |
| { | |
| BOOST_MATH_STD_USING | |
| static const char* function = "boost::math::expint<%1%>(%1%)"; | |
| if(z < 0) | |
| return -expint_imp(1, -z, pol, tag); | |
| if(z == 0) | |
| return -policies::raise_overflow_error<T>(function, 0, pol); | |
| T result; | |
| if(z <= 6) | |
| { | |
| // Maximum Deviation Found: 2.852e-18 | |
| // Expected Error Term: 2.852e-18 | |
| // Max Error found at double precision = Poly: 2.636335e-16 Cheb: 4.187027e-16 | |
| static const T P[10] = { | |
| 2.98677224343598593013L, | |
| 0.356343618769377415068L, | |
| 0.780836076283730801839L, | |
| 0.114670926327032002811L, | |
| 0.0499434773576515260534L, | |
| 0.00726224593341228159561L, | |
| 0.00115478237227804306827L, | |
| 0.000116419523609765200999L, | |
| 0.798296365679269702435e-5L, | |
| 0.2777056254402008721e-6L | |
| }; | |
| static const T Q[8] = { | |
| 1L, | |
| -1.17090412365413911947L, | |
| 0.62215109846016746276L, | |
| -0.195114782069495403315L, | |
| 0.0391523431392967238166L, | |
| -0.00504800158663705747345L, | |
| 0.000389034007436065401822L, | |
| -0.138972589601781706598e-4L | |
| }; | |
| static const T r1 = static_cast<T>(1677624236387711.0L / 4503599627370496.0L); | |
| static const T r2 = 0.131401834143860282009280387409357165515556574352422001206362e-16L; | |
| static const T r = static_cast<T>(0.372507410781366634461991866580119133535689497771654051555657435242200120636201854384926049951548942392L); | |
| T t = (z / 3) - 1; | |
| result = tools::evaluate_polynomial(P, t) | |
| / tools::evaluate_polynomial(Q, t); | |
| t = (z - r1) - r2; | |
| result *= t; | |
| if(fabs(t) < 0.1) | |
| { | |
| result += boost::math::log1p(t / r); | |
| } | |
| else | |
| { | |
| result += log(z / r); | |
| } | |
| } | |
| else if (z <= 10) | |
| { | |
| // Maximum Deviation Found: 6.546e-17 | |
| // Expected Error Term: 6.546e-17 | |
| // Max Error found at double precision = Poly: 6.890169e-17 Cheb: 6.772128e-17 | |
| static const T Y = 1.158985137939453125F; | |
| static const T P[8] = { | |
| 0.00139324086199402804173L, | |
| -0.0349921221823888744966L, | |
| -0.0264095520754134848538L, | |
| -0.00761224003005476438412L, | |
| -0.00247496209592143627977L, | |
| -0.000374885917942100256775L, | |
| -0.554086272024881826253e-4L, | |
| -0.396487648924804510056e-5L | |
| }; | |
| static const T Q[8] = { | |
| 1L, | |
| 0.744625566823272107711L, | |
| 0.329061095011767059236L, | |
| 0.100128624977313872323L, | |
| 0.0223851099128506347278L, | |
| 0.00365334190742316650106L, | |
| 0.000402453408512476836472L, | |
| 0.263649630720255691787e-4L | |
| }; | |
| T t = z / 2 - 4; | |
| result = Y + tools::evaluate_polynomial(P, t) | |
| / tools::evaluate_polynomial(Q, t); | |
| result *= exp(z) / z; | |
| result += z; | |
| } | |
| else if(z <= 20) | |
| { | |
| // Maximum Deviation Found: 1.843e-17 | |
| // Expected Error Term: -1.842e-17 | |
| // Max Error found at double precision = Poly: 4.375868e-17 Cheb: 5.860967e-17 | |
| static const T Y = 1.0869731903076171875F; | |
| static const T P[9] = { | |
| -0.00893891094356945667451L, | |
| -0.0484607730127134045806L, | |
| -0.0652810444222236895772L, | |
| -0.0478447572647309671455L, | |
| -0.0226059218923777094596L, | |
| -0.00720603636917482065907L, | |
| -0.00155941947035972031334L, | |
| -0.000209750022660200888349L, | |
| -0.138652200349182596186e-4L | |
| }; | |
| static const T Q[9] = { | |
| 1L, | |
| 1.97017214039061194971L, | |
| 1.86232465043073157508L, | |
| 1.09601437090337519977L, | |
| 0.438873285773088870812L, | |
| 0.122537731979686102756L, | |
| 0.0233458478275769288159L, | |
| 0.00278170769163303669021L, | |
| 0.000159150281166108755531L | |
| }; | |
| T t = z / 5 - 3; | |
| result = Y + tools::evaluate_polynomial(P, t) | |
| / tools::evaluate_polynomial(Q, t); | |
| result *= exp(z) / z; | |
| result += z; | |
| } | |
| else if(z <= 40) | |
| { | |
| // Maximum Deviation Found: 5.102e-18 | |
| // Expected Error Term: 5.101e-18 | |
| // Max Error found at double precision = Poly: 1.441088e-16 Cheb: 1.864792e-16 | |
| static const T Y = 1.03937530517578125F; | |
| static const T P[9] = { | |
| -0.00356165148914447597995L, | |
| -0.0229930320357982333406L, | |
| -0.0449814350482277917716L, | |
| -0.0453759383048193402336L, | |
| -0.0272050837209380717069L, | |
| -0.00994403059883350813295L, | |
| -0.00207592267812291726961L, | |
| -0.000192178045857733706044L, | |
| -0.113161784705911400295e-9L | |
| }; | |
| static const T Q[9] = { | |
| 1L, | |
| 2.84354408840148561131L, | |
| 3.6599610090072393012L, | |
| 2.75088464344293083595L, | |
| 1.2985244073998398643L, | |
| 0.383213198510794507409L, | |
| 0.0651165455496281337831L, | |
| 0.00488071077519227853585L | |
| }; | |
| T t = z / 10 - 3; | |
| result = Y + tools::evaluate_polynomial(P, t) | |
| / tools::evaluate_polynomial(Q, t); | |
| result *= exp(z) / z; | |
| result += z; | |
| } | |
| else | |
| { | |
| // Max Error found at double precision = 3.381886e-17 | |
| static const T exp40 = static_cast<T>(2.35385266837019985407899910749034804508871617254555467236651e17L); | |
| static const T Y= 1.013065338134765625F; | |
| static const T P[6] = { | |
| -0.0130653381347656243849L, | |
| 0.19029710559486576682L, | |
| 94.7365094537197236011L, | |
| -2516.35323679844256203L, | |
| 18932.0850014925993025L, | |
| -38703.1431362056714134L | |
| }; | |
| static const T Q[7] = { | |
| 1L, | |
| 61.9733592849439884145L, | |
| -2354.56211323420194283L, | |
| 22329.1459489893079041L, | |
| -70126.245140396567133L, | |
| 54738.2833147775537106L, | |
| 8297.16296356518409347L | |
| }; | |
| T t = 1 / z; | |
| result = Y + tools::evaluate_polynomial(P, t) | |
| / tools::evaluate_polynomial(Q, t); | |
| if(z < 41) | |
| result *= exp(z) / z; | |
| else | |
| { | |
| // Avoid premature overflow if we can: | |
| t = z - 40; | |
| if(t > tools::log_max_value<T>()) | |
| { | |
| result = policies::raise_overflow_error<T>(function, 0, pol); | |
| } | |
| else | |
| { | |
| result *= exp(z - 40) / z; | |
| if(result > tools::max_value<T>() / exp40) | |
| { | |
| result = policies::raise_overflow_error<T>(function, 0, pol); | |
| } | |
| else | |
| { | |
| result *= exp40; | |
| } | |
| } | |
| } | |
| result += z; | |
| } | |
| return result; | |
| } | |
| template <class T, class Policy> | |
| T expint_i_imp(T z, const Policy& pol, const mpl::int_<64>& tag) | |
| { | |
| BOOST_MATH_STD_USING | |
| static const char* function = "boost::math::expint<%1%>(%1%)"; | |
| if(z < 0) | |
| return -expint_imp(1, -z, pol, tag); | |
| if(z == 0) | |
| return -policies::raise_overflow_error<T>(function, 0, pol); | |
| T result; | |
| if(z <= 6) | |
| { | |
| // Maximum Deviation Found: 3.883e-21 | |
| // Expected Error Term: 3.883e-21 | |
| // Max Error found at long double precision = Poly: 3.344801e-19 Cheb: 4.989937e-19 | |
| static const T P[11] = { | |
| 2.98677224343598593764L, | |
| 0.25891613550886736592L, | |
| 0.789323584998672832285L, | |
| 0.092432587824602399339L, | |
| 0.0514236978728625906656L, | |
| 0.00658477469745132977921L, | |
| 0.00124914538197086254233L, | |
| 0.000131429679565472408551L, | |
| 0.11293331317982763165e-4L, | |
| 0.629499283139417444244e-6L, | |
| 0.177833045143692498221e-7L | |
| }; | |
| static const T Q[9] = { | |
| 1L, | |
| -1.20352377969742325748L, | |
| 0.66707904942606479811L, | |
| -0.223014531629140771914L, | |
| 0.0493340022262908008636L, | |
| -0.00741934273050807310677L, | |
| 0.00074353567782087939294L, | |
| -0.455861727069603367656e-4L, | |
| 0.131515429329812837701e-5L | |
| }; | |
| static const T r1 = static_cast<T>(1677624236387711.0L / 4503599627370496.0L); | |
| static const T r2 = 0.131401834143860282009280387409357165515556574352422001206362e-16L; | |
| static const T r = static_cast<T>(0.372507410781366634461991866580119133535689497771654051555657435242200120636201854384926049951548942392L); | |
| T t = (z / 3) - 1; | |
| result = tools::evaluate_polynomial(P, t) | |
| / tools::evaluate_polynomial(Q, t); | |
| t = (z - r1) - r2; | |
| result *= t; | |
| if(fabs(t) < 0.1) | |
| { | |
| result += boost::math::log1p(t / r); | |
| } | |
| else | |
| { | |
| result += log(z / r); | |
| } | |
| } | |
| else if (z <= 10) | |
| { | |
| // Maximum Deviation Found: 2.622e-21 | |
| // Expected Error Term: -2.622e-21 | |
| // Max Error found at long double precision = Poly: 1.208328e-20 Cheb: 1.073723e-20 | |
| static const T Y = 1.158985137939453125F; | |
| static const T P[9] = { | |
| 0.00139324086199409049399L, | |
| -0.0345238388952337563247L, | |
| -0.0382065278072592940767L, | |
| -0.0156117003070560727392L, | |
| -0.00383276012430495387102L, | |
| -0.000697070540945496497992L, | |
| -0.877310384591205930343e-4L, | |
| -0.623067256376494930067e-5L, | |
| -0.377246883283337141444e-6L | |
| }; | |
| static const T Q[10] = { | |
| 1L, | |
| 1.08073635708902053767L, | |
| 0.553681133533942532909L, | |
| 0.176763647137553797451L, | |
| 0.0387891748253869928121L, | |
| 0.0060603004848394727017L, | |
| 0.000670519492939992806051L, | |
| 0.4947357050100855646e-4L, | |
| 0.204339282037446434827e-5L, | |
| 0.146951181174930425744e-7L | |
| }; | |
| T t = z / 2 - 4; | |
| result = Y + tools::evaluate_polynomial(P, t) | |
| / tools::evaluate_polynomial(Q, t); | |
| result *= exp(z) / z; | |
| result += z; | |
| } | |
| else if(z <= 20) | |
| { | |
| // Maximum Deviation Found: 3.220e-20 | |
| // Expected Error Term: 3.220e-20 | |
| // Max Error found at long double precision = Poly: 7.696841e-20 Cheb: 6.205163e-20 | |
| static const T Y = 1.0869731903076171875F; | |
| static const T P[10] = { | |
| -0.00893891094356946995368L, | |
| -0.0487562980088748775943L, | |
| -0.0670568657950041926085L, | |
| -0.0509577352851442932713L, | |
| -0.02551800927409034206L, | |
| -0.00892913759760086687083L, | |
| -0.00224469630207344379888L, | |
| -0.000392477245911296982776L, | |
| -0.44424044184395578775e-4L, | |
| -0.252788029251437017959e-5L | |
| }; | |
| static const T Q[10] = { | |
| 1L, | |
| 2.00323265503572414261L, | |
| 1.94688958187256383178L, | |
| 1.19733638134417472296L, | |
| 0.513137726038353385661L, | |
| 0.159135395578007264547L, | |
| 0.0358233587351620919881L, | |
| 0.0056716655597009417875L, | |
| 0.000577048986213535829925L, | |
| 0.290976943033493216793e-4L | |
| }; | |
| T t = z / 5 - 3; | |
| result = Y + tools::evaluate_polynomial(P, t) | |
| / tools::evaluate_polynomial(Q, t); | |
| result *= exp(z) / z; | |
| result += z; | |
| } | |
| else if(z <= 40) | |
| { | |
| // Maximum Deviation Found: 2.940e-21 | |
| // Expected Error Term: -2.938e-21 | |
| // Max Error found at long double precision = Poly: 3.419893e-19 Cheb: 3.359874e-19 | |
| static const T Y = 1.03937530517578125F; | |
| static const T P[12] = { | |
| -0.00356165148914447278177L, | |
| -0.0240235006148610849678L, | |
| -0.0516699967278057976119L, | |
| -0.0586603078706856245674L, | |
| -0.0409960120868776180825L, | |
| -0.0185485073689590665153L, | |
| -0.00537842101034123222417L, | |
| -0.000920988084778273760609L, | |
| -0.716742618812210980263e-4L, | |
| -0.504623302166487346677e-9L, | |
| 0.712662196671896837736e-10L, | |
| -0.533769629702262072175e-11L | |
| }; | |
| static const T Q[9] = { | |
| 1L, | |
| 3.13286733695729715455L, | |
| 4.49281223045653491929L, | |
| 3.84900294427622911374L, | |
| 2.15205199043580378211L, | |
| 0.802912186540269232424L, | |
| 0.194793170017818925388L, | |
| 0.0280128013584653182994L, | |
| 0.00182034930799902922549L | |
| }; | |
| T t = z / 10 - 3; | |
| result = Y + tools::evaluate_polynomial(P, t) | |
| / tools::evaluate_polynomial(Q, t); | |
| BOOST_MATH_INSTRUMENT_VARIABLE(result) | |
| result *= exp(z) / z; | |
| BOOST_MATH_INSTRUMENT_VARIABLE(result) | |
| result += z; | |
| BOOST_MATH_INSTRUMENT_VARIABLE(result) | |
| } | |
| else | |
| { | |
| // Maximum Deviation Found: 3.536e-20 | |
| // Max Error found at long double precision = Poly: 1.310671e-19 Cheb: 8.630943e-11 | |
| static const T exp40 = static_cast<T>(2.35385266837019985407899910749034804508871617254555467236651e17L); | |
| static const T Y= 1.013065338134765625F; | |
| static const T P[9] = { | |
| -0.0130653381347656250004L, | |
| 0.644487780349757303739L, | |
| 143.995670348227433964L, | |
| -13918.9322758014173709L, | |
| 476260.975133624194484L, | |
| -7437102.15135982802122L, | |
| 53732298.8764767916542L, | |
| -160695051.957997452509L, | |
| 137839271.592778020028L | |
| }; | |
| static const T Q[9] = { | |
| 1L, | |
| 27.2103343964943718802L, | |
| -8785.48528692879413676L, | |
| 397530.290000322626766L, | |
| -7356441.34957799368252L, | |
| 63050914.5343400957524L, | |
| -246143779.638307701369L, | |
| 384647824.678554961174L, | |
| -166288297.874583961493L | |
| }; | |
| T t = 1 / z; | |
| result = Y + tools::evaluate_polynomial(P, t) | |
| / tools::evaluate_polynomial(Q, t); | |
| if(z < 41) | |
| result *= exp(z) / z; | |
| else | |
| { | |
| // Avoid premature overflow if we can: | |
| t = z - 40; | |
| if(t > tools::log_max_value<T>()) | |
| { | |
| result = policies::raise_overflow_error<T>(function, 0, pol); | |
| } | |
| else | |
| { | |
| result *= exp(z - 40) / z; | |
| if(result > tools::max_value<T>() / exp40) | |
| { | |
| result = policies::raise_overflow_error<T>(function, 0, pol); | |
| } | |
| else | |
| { | |
| result *= exp40; | |
| } | |
| } | |
| } | |
| result += z; | |
| } | |
| return result; | |
| } | |
| template <class T, class Policy> | |
| T expint_i_imp(T z, const Policy& pol, const mpl::int_<113>& tag) | |
| { | |
| BOOST_MATH_STD_USING | |
| static const char* function = "boost::math::expint<%1%>(%1%)"; | |
| if(z < 0) | |
| return -expint_imp(1, -z, pol, tag); | |
| if(z == 0) | |
| return -policies::raise_overflow_error<T>(function, 0, pol); | |
| T result; | |
| if(z <= 6) | |
| { | |
| // Maximum Deviation Found: 1.230e-36 | |
| // Expected Error Term: -1.230e-36 | |
| // Max Error found at long double precision = Poly: 4.355299e-34 Cheb: 7.512581e-34 | |
| static const T P[15] = { | |
| 2.98677224343598593765287235997328555L, | |
| -0.333256034674702967028780537349334037L, | |
| 0.851831522798101228384971644036708463L, | |
| -0.0657854833494646206186773614110374948L, | |
| 0.0630065662557284456000060708977935073L, | |
| -0.00311759191425309373327784154659649232L, | |
| 0.00176213568201493949664478471656026771L, | |
| -0.491548660404172089488535218163952295e-4L, | |
| 0.207764227621061706075562107748176592e-4L, | |
| -0.225445398156913584846374273379402765e-6L, | |
| 0.996939977231410319761273881672601592e-7L, | |
| 0.212546902052178643330520878928100847e-9L, | |
| 0.154646053060262871360159325115980023e-9L, | |
| 0.143971277122049197323415503594302307e-11L, | |
| 0.306243138978114692252817805327426657e-13L | |
| }; | |
| static const T Q[15] = { | |
| 1L, | |
| -1.40178870313943798705491944989231793L, | |
| 0.943810968269701047641218856758605284L, | |
| -0.405026631534345064600850391026113165L, | |
| 0.123924153524614086482627660399122762L, | |
| -0.0286364505373369439591132549624317707L, | |
| 0.00516148845910606985396596845494015963L, | |
| -0.000738330799456364820380739850924783649L, | |
| 0.843737760991856114061953265870882637e-4L, | |
| -0.767957673431982543213661388914587589e-5L, | |
| 0.549136847313854595809952100614840031e-6L, | |
| -0.299801381513743676764008325949325404e-7L, | |
| 0.118419479055346106118129130945423483e-8L, | |
| -0.30372295663095470359211949045344607e-10L, | |
| 0.382742953753485333207877784720070523e-12L | |
| }; | |
| static const T r1 = static_cast<T>(1677624236387711.0L / 4503599627370496.0L); | |
| static const T r2 = static_cast<T>(266514582277687.0L / 4503599627370496.0L / 4503599627370496.0L); | |
| static const T r3 = static_cast<T>(0.283806480836357377069325311780969887585024578164571984232357e-31L); | |
| static const T r = static_cast<T>(0.372507410781366634461991866580119133535689497771654051555657435242200120636201854384926049951548942392L); | |
| T t = (z / 3) - 1; | |
| result = tools::evaluate_polynomial(P, t) | |
| / tools::evaluate_polynomial(Q, t); | |
| t = ((z - r1) - r2) - r3; | |
| result *= t; | |
| if(fabs(t) < 0.1) | |
| { | |
| result += boost::math::log1p(t / r); | |
| } | |
| else | |
| { | |
| result += log(z / r); | |
| } | |
| } | |
| else if (z <= 10) | |
| { | |
| // Maximum Deviation Found: 7.779e-36 | |
| // Expected Error Term: -7.779e-36 | |
| // Max Error found at long double precision = Poly: 2.576723e-35 Cheb: 1.236001e-34 | |
| static const T Y = 1.158985137939453125F; | |
| static const T P[15] = { | |
| 0.00139324086199409049282472239613554817L, | |
| -0.0338173111691991289178779840307998955L, | |
| -0.0555972290794371306259684845277620556L, | |
| -0.0378677976003456171563136909186202177L, | |
| -0.0152221583517528358782902783914356667L, | |
| -0.00428283334203873035104248217403126905L, | |
| -0.000922782631491644846511553601323435286L, | |
| -0.000155513428088853161562660696055496696L, | |
| -0.205756580255359882813545261519317096e-4L, | |
| -0.220327406578552089820753181821115181e-5L, | |
| -0.189483157545587592043421445645377439e-6L, | |
| -0.122426571518570587750898968123803867e-7L, | |
| -0.635187358949437991465353268374523944e-9L, | |
| -0.203015132965870311935118337194860863e-10L, | |
| -0.384276705503357655108096065452950822e-12L | |
| }; | |
| static const T Q[15] = { | |
| 1L, | |
| 1.58784732785354597996617046880946257L, | |
| 1.18550755302279446339364262338114098L, | |
| 0.55598993549661368604527040349702836L, | |
| 0.184290888380564236919107835030984453L, | |
| 0.0459658051803613282360464632326866113L, | |
| 0.0089505064268613225167835599456014705L, | |
| 0.00139042673882987693424772855926289077L, | |
| 0.000174210708041584097450805790176479012L, | |
| 0.176324034009707558089086875136647376e-4L, | |
| 0.142935845999505649273084545313710581e-5L, | |
| 0.907502324487057260675816233312747784e-7L, | |
| 0.431044337808893270797934621235918418e-8L, | |
| 0.139007266881450521776529705677086902e-9L, | |
| 0.234715286125516430792452741830364672e-11L | |
| }; | |
| T t = z / 2 - 4; | |
| result = Y + tools::evaluate_polynomial(P, t) | |
| / tools::evaluate_polynomial(Q, t); | |
| result *= exp(z) / z; | |
| result += z; | |
| } | |
| else if(z <= 18) | |
| { | |
| // Maximum Deviation Found: 1.082e-34 | |
| // Expected Error Term: 1.080e-34 | |
| // Max Error found at long double precision = Poly: 1.958294e-34 Cheb: 2.472261e-34 | |
| static const T Y = 1.091579437255859375F; | |
| static const T P[17] = { | |
| -0.00685089599550151282724924894258520532L, | |
| -0.0443313550253580053324487059748497467L, | |
| -0.071538561252424027443296958795814874L, | |
| -0.0622923153354102682285444067843300583L, | |
| -0.0361631270264607478205393775461208794L, | |
| -0.0153192826839624850298106509601033261L, | |
| -0.00496967904961260031539602977748408242L, | |
| -0.00126989079663425780800919171538920589L, | |
| -0.000258933143097125199914724875206326698L, | |
| -0.422110326689204794443002330541441956e-4L, | |
| -0.546004547590412661451073996127115221e-5L, | |
| -0.546775260262202177131068692199272241e-6L, | |
| -0.404157632825805803833379568956559215e-7L, | |
| -0.200612596196561323832327013027419284e-8L, | |
| -0.502538501472133913417609379765434153e-10L, | |
| -0.326283053716799774936661568391296584e-13L, | |
| 0.869226483473172853557775877908693647e-15L | |
| }; | |
| static const T Q[15] = { | |
| 1L, | |
| 2.23227220874479061894038229141871087L, | |
| 2.40221000361027971895657505660959863L, | |
| 1.65476320985936174728238416007084214L, | |
| 0.816828602963895720369875535001248227L, | |
| 0.306337922909446903672123418670921066L, | |
| 0.0902400121654409267774593230720600752L, | |
| 0.0212708882169429206498765100993228086L, | |
| 0.00404442626252467471957713495828165491L, | |
| 0.0006195601618842253612635241404054589L, | |
| 0.755930932686543009521454653994321843e-4L, | |
| 0.716004532773778954193609582677482803e-5L, | |
| 0.500881663076471627699290821742924233e-6L, | |
| 0.233593219218823384508105943657387644e-7L, | |
| 0.554900353169148897444104962034267682e-9L | |
| }; | |
| T t = z / 4 - 3.5; | |
| result = Y + tools::evaluate_polynomial(P, t) | |
| / tools::evaluate_polynomial(Q, t); | |
| result *= exp(z) / z; | |
| result += z; | |
| } | |
| else if(z <= 26) | |
| { | |
| // Maximum Deviation Found: 3.163e-35 | |
| // Expected Error Term: 3.163e-35 | |
| // Max Error found at long double precision = Poly: 4.158110e-35 Cheb: 5.385532e-35 | |
| static const T Y = 1.051731109619140625F; | |
| static const T P[14] = { | |
| -0.00144552494420652573815404828020593565L, | |
| -0.0126747451594545338365684731262912741L, | |
| -0.01757394877502366717526779263438073L, | |
| -0.0126838952395506921945756139424722588L, | |
| -0.0060045057928894974954756789352443522L, | |
| -0.00205349237147226126653803455793107903L, | |
| -0.000532606040579654887676082220195624207L, | |
| -0.000107344687098019891474772069139014662L, | |
| -0.169536802705805811859089949943435152e-4L, | |
| -0.20863311729206543881826553010120078e-5L, | |
| -0.195670358542116256713560296776654385e-6L, | |
| -0.133291168587253145439184028259772437e-7L, | |
| -0.595500337089495614285777067722823397e-9L, | |
| -0.133141358866324100955927979606981328e-10L | |
| }; | |
| static const T Q[14] = { | |
| 1L, | |
| 1.72490783907582654629537013560044682L, | |
| 1.44524329516800613088375685659759765L, | |
| 0.778241785539308257585068744978050181L, | |
| 0.300520486589206605184097270225725584L, | |
| 0.0879346899691339661394537806057953957L, | |
| 0.0200802415843802892793583043470125006L, | |
| 0.00362842049172586254520256100538273214L, | |
| 0.000519731362862955132062751246769469957L, | |
| 0.584092147914050999895178697392282665e-4L, | |
| 0.501851497707855358002773398333542337e-5L, | |
| 0.313085677467921096644895738538865537e-6L, | |
| 0.127552010539733113371132321521204458e-7L, | |
| 0.25737310826983451144405899970774587e-9L | |
| }; | |
| T t = z / 4 - 5.5; | |
| result = Y + tools::evaluate_polynomial(P, t) | |
| / tools::evaluate_polynomial(Q, t); | |
| BOOST_MATH_INSTRUMENT_VARIABLE(result) | |
| result *= exp(z) / z; | |
| BOOST_MATH_INSTRUMENT_VARIABLE(result) | |
| result += z; | |
| BOOST_MATH_INSTRUMENT_VARIABLE(result) | |
| } | |
| else if(z <= 42) | |
| { | |
| // Maximum Deviation Found: 7.972e-36 | |
| // Expected Error Term: 7.962e-36 | |
| // Max Error found at long double precision = Poly: 1.711721e-34 Cheb: 3.100018e-34 | |
| static const T Y = 1.032726287841796875F; | |
| static const T P[15] = { | |
| -0.00141056919297307534690895009969373233L, | |
| -0.0123384175302540291339020257071411437L, | |
| -0.0298127270706864057791526083667396115L, | |
| -0.0390686759471630584626293670260768098L, | |
| -0.0338226792912607409822059922949035589L, | |
| -0.0211659736179834946452561197559654582L, | |
| -0.0100428887460879377373158821400070313L, | |
| -0.00370717396015165148484022792801682932L, | |
| -0.0010768667551001624764329000496561659L, | |
| -0.000246127328761027039347584096573123531L, | |
| -0.437318110527818613580613051861991198e-4L, | |
| -0.587532682329299591501065482317771497e-5L, | |
| -0.565697065670893984610852937110819467e-6L, | |
| -0.350233957364028523971768887437839573e-7L, | |
| -0.105428907085424234504608142258423505e-8L | |
| }; | |
| static const T Q[16] = { | |
| 1L, | |
| 3.17261315255467581204685605414005525L, | |
| 4.85267952971640525245338392887217426L, | |
| 4.74341914912439861451492872946725151L, | |
| 3.31108463283559911602405970817931801L, | |
| 1.74657006336994649386607925179848899L, | |
| 0.718255607416072737965933040353653244L, | |
| 0.234037553177354542791975767960643864L, | |
| 0.0607470145906491602476833515412605389L, | |
| 0.0125048143774226921434854172947548724L, | |
| 0.00201034366420433762935768458656609163L, | |
| 0.000244823338417452367656368849303165721L, | |
| 0.213511655166983177960471085462540807e-4L, | |
| 0.119323998465870686327170541547982932e-5L, | |
| 0.322153582559488797803027773591727565e-7L, | |
| -0.161635525318683508633792845159942312e-16L | |
| }; | |
| T t = z / 8 - 4.25; | |
| result = Y + tools::evaluate_polynomial(P, t) | |
| / tools::evaluate_polynomial(Q, t); | |
| BOOST_MATH_INSTRUMENT_VARIABLE(result) | |
| result *= exp(z) / z; | |
| BOOST_MATH_INSTRUMENT_VARIABLE(result) | |
| result += z; | |
| BOOST_MATH_INSTRUMENT_VARIABLE(result) | |
| } | |
| else if(z <= 56) | |
| { | |
| // Maximum Deviation Found: 4.469e-36 | |
| // Expected Error Term: 4.468e-36 | |
| // Max Error found at long double precision = Poly: 1.288958e-35 Cheb: 2.304586e-35 | |
| static const T Y = 1.0216197967529296875F; | |
| static const T P[12] = { | |
| -0.000322999116096627043476023926572650045L, | |
| -0.00385606067447365187909164609294113346L, | |
| -0.00686514524727568176735949971985244415L, | |
| -0.00606260649593050194602676772589601799L, | |
| -0.00334382362017147544335054575436194357L, | |
| -0.00126108534260253075708625583630318043L, | |
| -0.000337881489347846058951220431209276776L, | |
| -0.648480902304640018785370650254018022e-4L, | |
| -0.87652644082970492211455290209092766e-5L, | |
| -0.794712243338068631557849449519994144e-6L, | |
| -0.434084023639508143975983454830954835e-7L, | |
| -0.107839681938752337160494412638656696e-8L | |
| }; | |
| static const T Q[12] = { | |
| 1L, | |
| 2.09913805456661084097134805151524958L, | |
| 2.07041755535439919593503171320431849L, | |
| 1.26406517226052371320416108604874734L, | |
| 0.529689923703770353961553223973435569L, | |
| 0.159578150879536711042269658656115746L, | |
| 0.0351720877642000691155202082629857131L, | |
| 0.00565313621289648752407123620997063122L, | |
| 0.000646920278540515480093843570291218295L, | |
| 0.499904084850091676776993523323213591e-4L, | |
| 0.233740058688179614344680531486267142e-5L, | |
| 0.498800627828842754845418576305379469e-7L | |
| }; | |
| T t = z / 7 - 7; | |
| result = Y + tools::evaluate_polynomial(P, t) | |
| / tools::evaluate_polynomial(Q, t); | |
| BOOST_MATH_INSTRUMENT_VARIABLE(result) | |
| result *= exp(z) / z; | |
| BOOST_MATH_INSTRUMENT_VARIABLE(result) | |
| result += z; | |
| BOOST_MATH_INSTRUMENT_VARIABLE(result) | |
| } | |
| else if(z <= 84) | |
| { | |
| // Maximum Deviation Found: 5.588e-35 | |
| // Expected Error Term: -5.566e-35 | |
| // Max Error found at long double precision = Poly: 9.976345e-35 Cheb: 8.358865e-35 | |
| static const T Y = 1.015148162841796875F; | |
| static const T P[11] = { | |
| -0.000435714784725086961464589957142615216L, | |
| -0.00432114324353830636009453048419094314L, | |
| -0.0100740363285526177522819204820582424L, | |
| -0.0116744115827059174392383504427640362L, | |
| -0.00816145387784261141360062395898644652L, | |
| -0.00371380272673500791322744465394211508L, | |
| -0.00112958263488611536502153195005736563L, | |
| -0.000228316462389404645183269923754256664L, | |
| -0.29462181955852860250359064291292577e-4L, | |
| -0.21972450610957417963227028788460299e-5L, | |
| -0.720558173805289167524715527536874694e-7L | |
| }; | |
| static const T Q[11] = { | |
| 1L, | |
| 2.95918362458402597039366979529287095L, | |
| 3.96472247520659077944638411856748924L, | |
| 3.15563251550528513747923714884142131L, | |
| 1.64674612007093983894215359287448334L, | |
| 0.58695020129846594405856226787156424L, | |
| 0.144358385319329396231755457772362793L, | |
| 0.024146911506411684815134916238348063L, | |
| 0.0026257132337460784266874572001650153L, | |
| 0.000167479843750859222348869769094711093L, | |
| 0.475673638665358075556452220192497036e-5L | |
| }; | |
| T t = z / 14 - 5; | |
| result = Y + tools::evaluate_polynomial(P, t) | |
| / tools::evaluate_polynomial(Q, t); | |
| BOOST_MATH_INSTRUMENT_VARIABLE(result) | |
| result *= exp(z) / z; | |
| BOOST_MATH_INSTRUMENT_VARIABLE(result) | |
| result += z; | |
| BOOST_MATH_INSTRUMENT_VARIABLE(result) | |
| } | |
| else if(z <= 210) | |
| { | |
| // Maximum Deviation Found: 4.448e-36 | |
| // Expected Error Term: 4.445e-36 | |
| // Max Error found at long double precision = Poly: 2.058532e-35 Cheb: 2.165465e-27 | |
| static const T Y= 1.00849151611328125F; | |
| static const T P[9] = { | |
| -0.0084915161132812500000001440233607358L, | |
| 1.84479378737716028341394223076147872L, | |
| -130.431146923726715674081563022115568L, | |
| 4336.26945491571504885214176203512015L, | |
| -76279.0031974974730095170437591004177L, | |
| 729577.956271997673695191455111727774L, | |
| -3661928.69330208734947103004900349266L, | |
| 8570600.041606912735872059184527855L, | |
| -6758379.93672362080947905580906028645L | |
| }; | |
| static const T Q[10] = { | |
| 1L, | |
| -99.4868026047611434569541483506091713L, | |
| 3879.67753690517114249705089803055473L, | |
| -76495.82413252517165830203774900806L, | |
| 820773.726408311894342553758526282667L, | |
| -4803087.64956923577571031564909646579L, | |
| 14521246.227703545012713173740895477L, | |
| -19762752.0196769712258527849159393044L, | |
| 8354144.67882768405803322344185185517L, | |
| 355076.853106511136734454134915432571L | |
| }; | |
| T t = 1 / z; | |
| result = Y + tools::evaluate_polynomial(P, t) | |
| / tools::evaluate_polynomial(Q, t); | |
| result *= exp(z) / z; | |
| result += z; | |
| } | |
| else // z > 210 | |
| { | |
| // Maximum Deviation Found: 3.963e-37 | |
| // Expected Error Term: 3.963e-37 | |
| // Max Error found at long double precision = Poly: 1.248049e-36 Cheb: 2.843486e-29 | |
| static const T exp40 = static_cast<T>(2.35385266837019985407899910749034804508871617254555467236651e17L); | |
| static const T Y= 1.00252532958984375F; | |
| static const T P[8] = { | |
| -0.00252532958984375000000000000000000085L, | |
| 1.16591386866059087390621952073890359L, | |
| -67.8483431314018462417456828499277579L, | |
| 1567.68688154683822956359536287575892L, | |
| -17335.4683325819116482498725687644986L, | |
| 93632.6567462673524739954389166550069L, | |
| -225025.189335919133214440347510936787L, | |
| 175864.614717440010942804684741336853L | |
| }; | |
| static const T Q[9] = { | |
| 1L, | |
| -65.6998869881600212224652719706425129L, | |
| 1642.73850032324014781607859416890077L, | |
| -19937.2610222467322481947237312818575L, | |
| 124136.267326632742667972126625064538L, | |
| -384614.251466704550678760562965502293L, | |
| 523355.035910385688578278384032026998L, | |
| -217809.552260834025885677791936351294L, | |
| -8555.81719551123640677261226549550872L | |
| }; | |
| T t = 1 / z; | |
| result = Y + tools::evaluate_polynomial(P, t) | |
| / tools::evaluate_polynomial(Q, t); | |
| if(z < 41) | |
| result *= exp(z) / z; | |
| else | |
| { | |
| // Avoid premature overflow if we can: | |
| t = z - 40; | |
| if(t > tools::log_max_value<T>()) | |
| { | |
| result = policies::raise_overflow_error<T>(function, 0, pol); | |
| } | |
| else | |
| { | |
| result *= exp(z - 40) / z; | |
| if(result > tools::max_value<T>() / exp40) | |
| { | |
| result = policies::raise_overflow_error<T>(function, 0, pol); | |
| } | |
| else | |
| { | |
| result *= exp40; | |
| } | |
| } | |
| } | |
| result += z; | |
| } | |
| return result; | |
| } | |
| template <class T, class Policy> | |
| inline typename tools::promote_args<T>::type | |
| expint_forwarder(T z, const Policy& /*pol*/, mpl::true_ const&) | |
| { | |
| typedef typename tools::promote_args<T>::type result_type; | |
| typedef typename policies::evaluation<result_type, Policy>::type value_type; | |
| typedef typename policies::precision<result_type, Policy>::type precision_type; | |
| typedef typename policies::normalise< | |
| Policy, | |
| policies::promote_float<false>, | |
| policies::promote_double<false>, | |
| policies::discrete_quantile<>, | |
| policies::assert_undefined<> >::type forwarding_policy; | |
| typedef typename mpl::if_< | |
| mpl::less_equal<precision_type, mpl::int_<0> >, | |
| mpl::int_<0>, | |
| typename mpl::if_< | |
| mpl::less_equal<precision_type, mpl::int_<53> >, | |
| mpl::int_<53>, // double | |
| typename mpl::if_< | |
| mpl::less_equal<precision_type, mpl::int_<64> >, | |
| mpl::int_<64>, // 80-bit long double | |
| typename mpl::if_< | |
| mpl::less_equal<precision_type, mpl::int_<113> >, | |
| mpl::int_<113>, // 128-bit long double | |
| mpl::int_<0> // too many bits, use generic version. | |
| >::type | |
| >::type | |
| >::type | |
| >::type tag_type; | |
| return policies::checked_narrowing_cast<result_type, forwarding_policy>(detail::expint_i_imp( | |
| static_cast<value_type>(z), | |
| forwarding_policy(), | |
| tag_type()), "boost::math::expint<%1%>(%1%)"); | |
| } | |
| template <class T> | |
| inline typename tools::promote_args<T>::type | |
| expint_forwarder(unsigned n, T z, const mpl::false_&) | |
| { | |
| return boost::math::expint(n, z, policies::policy<>()); | |
| } | |
| } // namespace detail | |
| template <class T, class Policy> | |
| inline typename tools::promote_args<T>::type | |
| expint(unsigned n, T z, const Policy& /*pol*/) | |
| { | |
| typedef typename tools::promote_args<T>::type result_type; | |
| typedef typename policies::evaluation<result_type, Policy>::type value_type; | |
| typedef typename policies::precision<result_type, Policy>::type precision_type; | |
| typedef typename policies::normalise< | |
| Policy, | |
| policies::promote_float<false>, | |
| policies::promote_double<false>, | |
| policies::discrete_quantile<>, | |
| policies::assert_undefined<> >::type forwarding_policy; | |
| typedef typename mpl::if_< | |
| mpl::less_equal<precision_type, mpl::int_<0> >, | |
| mpl::int_<0>, | |
| typename mpl::if_< | |
| mpl::less_equal<precision_type, mpl::int_<53> >, | |
| mpl::int_<53>, // double | |
| typename mpl::if_< | |
| mpl::less_equal<precision_type, mpl::int_<64> >, | |
| mpl::int_<64>, // 80-bit long double | |
| typename mpl::if_< | |
| mpl::less_equal<precision_type, mpl::int_<113> >, | |
| mpl::int_<113>, // 128-bit long double | |
| mpl::int_<0> // too many bits, use generic version. | |
| >::type | |
| >::type | |
| >::type | |
| >::type tag_type; | |
| return policies::checked_narrowing_cast<result_type, forwarding_policy>(detail::expint_imp( | |
| n, | |
| static_cast<value_type>(z), | |
| forwarding_policy(), | |
| tag_type()), "boost::math::expint<%1%>(unsigned, %1%)"); | |
| } | |
| template <class T, class U> | |
| inline typename detail::expint_result<T, U>::type | |
| expint(T const z, U const u) | |
| { | |
| typedef typename policies::is_policy<U>::type tag_type; | |
| return detail::expint_forwarder(z, u, tag_type()); | |
| } | |
| template <class T> | |
| inline typename tools::promote_args<T>::type | |
| expint(T z) | |
| { | |
| return expint(z, policies::policy<>()); | |
| } | |
| }} // namespaces | |
| #endif // BOOST_MATH_EXPINT_HPP | |