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1// (C) Copyright Matt Borland 2021 - 2022.2// Use, modification and distribution are subject to the3// Boost Software License, Version 1.0. (See accompanying file4// LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)5 6#ifndef BOOST_MATH_CCMATH_REMAINDER_HPP7#define BOOST_MATH_CCMATH_REMAINDER_HPP8 9#include <boost/math/ccmath/detail/config.hpp>10 11#ifdef BOOST_MATH_NO_CCMATH12#error "The header <boost/math/remainder.hpp> can only be used in C++17 and later."13#endif14 15#include <cstdint>16#include <boost/math/tools/promotion.hpp>17#include <boost/math/ccmath/abs.hpp>18#include <boost/math/ccmath/isinf.hpp>19#include <boost/math/ccmath/isnan.hpp>20#include <boost/math/ccmath/isfinite.hpp>21#include <boost/math/ccmath/modf.hpp>22 23namespace boost::math::ccmath {24 25namespace detail {26 27template <typename T>28constexpr T remainder_impl(const T x, const T y)29{30 T n = 0;31 32 if (T fractional_part = boost::math::ccmath::modf((x / y), &n); fractional_part > static_cast<T>(1.0/2))33 {34 ++n;35 }36 else if (fractional_part < static_cast<T>(-1.0/2))37 {38 --n;39 }40 41 return x - n*y;42}43 44} // Namespace detail45 46template <typename Real, std::enable_if_t<!std::is_integral_v<Real>, bool> = true>47constexpr Real remainder(Real x, Real y)48{49 if (BOOST_MATH_IS_CONSTANT_EVALUATED(x))50 {51 if (boost::math::ccmath::isinf(x) && !boost::math::ccmath::isnan(y))52 {53 return std::numeric_limits<Real>::quiet_NaN();54 }55 else if (boost::math::ccmath::abs(y) == static_cast<Real>(0) && !boost::math::ccmath::isnan(x))56 {57 return std::numeric_limits<Real>::quiet_NaN();58 }59 else if (boost::math::ccmath::isnan(x))60 {61 return x;62 }63 else if (boost::math::ccmath::isnan(y))64 {65 return y;66 }67 68 return boost::math::ccmath::detail::remainder_impl(x, y);69 }70 else71 {72 using std::remainder;73 return remainder(x, y);74 }75}76 77template <typename T1, typename T2>78constexpr auto remainder(T1 x, T2 y)79{80 if (BOOST_MATH_IS_CONSTANT_EVALUATED(x))81 {82 using promoted_type = boost::math::tools::promote_args_t<T1, T2>;83 return boost::math::ccmath::remainder(promoted_type(x), promoted_type(y));84 }85 else86 {87 using std::remainder;88 return remainder(x, y);89 }90}91 92constexpr float remainderf(float x, float y)93{94 return boost::math::ccmath::remainder(x, y);95}96 97#ifndef BOOST_MATH_NO_LONG_DOUBLE_MATH_FUNCTIONS98constexpr long double remainderl(long double x, long double y)99{100 return boost::math::ccmath::remainder(x, y);101}102#endif103 104} // Namespaces105 106#endif // BOOST_MATH_CCMATH_REMAINDER_HPP107