1 // Math extensions -*- C++ -*-
3 // Copyright (C) 2013-2017 Free Software Foundation, Inc.
5 // This file is part of the GNU ISO C++ Library. This library is free
6 // software; you can redistribute it and/or modify it under the
7 // terms of the GNU General Public License as published by the
8 // Free Software Foundation; either version 3, or (at your option)
11 // This library is distributed in the hope that it will be useful,
12 // but WITHOUT ANY WARRANTY; without even the implied warranty of
13 // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14 // GNU General Public License for more details.
16 // Under Section 7 of GPL version 3, you are granted additional
17 // permissions described in the GCC Runtime Library Exception, version
18 // 3.1, as published by the Free Software Foundation.
20 // You should have received a copy of the GNU General Public License and
21 // a copy of the GCC Runtime Library Exception along with this program;
22 // see the files COPYING3 and COPYING.RUNTIME respectively. If not, see
23 // <http://www.gnu.org/licenses/>.
26 * This file is a GNU extension to the Standard C++ Library.
32 #pragma GCC system_header
34 #if __cplusplus < 201103L
35 # include <bits/c++0x_warning.h>
39 #include <type_traits>
41 namespace __gnu_cxx _GLIBCXX_VISIBILITY(default)
43 _GLIBCXX_BEGIN_NAMESPACE_VERSION
45 // A class for math constants.
46 template<typename _RealType>
47 struct __math_constants
49 static_assert(std::is_floating_point<_RealType>::value,
50 "template argument not a floating point type");
52 // Constant @f$ \pi @f$.
53 static constexpr _RealType __pi = 3.1415926535897932384626433832795029L;
54 // Constant @f$ \pi / 2 @f$.
55 static constexpr _RealType __pi_half = 1.5707963267948966192313216916397514L;
56 // Constant @f$ \pi / 3 @f$.
57 static constexpr _RealType __pi_third = 1.0471975511965977461542144610931676L;
58 // Constant @f$ \pi / 4 @f$.
59 static constexpr _RealType __pi_quarter = 0.7853981633974483096156608458198757L;
60 // Constant @f$ \sqrt(\pi / 2) @f$.
61 static constexpr _RealType __root_pi_div_2 = 1.2533141373155002512078826424055226L;
62 // Constant @f$ 1 / \pi @f$.
63 static constexpr _RealType __one_div_pi = 0.3183098861837906715377675267450287L;
64 // Constant @f$ 2 / \pi @f$.
65 static constexpr _RealType __two_div_pi = 0.6366197723675813430755350534900574L;
66 // Constant @f$ 2 / \sqrt(\pi) @f$.
67 static constexpr _RealType __two_div_root_pi = 1.1283791670955125738961589031215452L;
69 // Constant Euler's number @f$ e @f$.
70 static constexpr _RealType __e = 2.7182818284590452353602874713526625L;
71 // Constant @f$ 1 / e @f$.
72 static constexpr _RealType __one_div_e = 0.36787944117144232159552377016146087L;
73 // Constant @f$ \log_2(e) @f$.
74 static constexpr _RealType __log2_e = 1.4426950408889634073599246810018921L;
75 // Constant @f$ \log_10(e) @f$.
76 static constexpr _RealType __log10_e = 0.4342944819032518276511289189166051L;
77 // Constant @f$ \ln(2) @f$.
78 static constexpr _RealType __ln_2 = 0.6931471805599453094172321214581766L;
79 // Constant @f$ \ln(3) @f$.
80 static constexpr _RealType __ln_3 = 1.0986122886681096913952452369225257L;
81 // Constant @f$ \ln(10) @f$.
82 static constexpr _RealType __ln_10 = 2.3025850929940456840179914546843642L;
84 // Constant Euler-Mascheroni @f$ \gamma_E @f$.
85 static constexpr _RealType __gamma_e = 0.5772156649015328606065120900824024L;
86 // Constant Golden Ratio @f$ \phi @f$.
87 static constexpr _RealType __phi = 1.6180339887498948482045868343656381L;
89 // Constant @f$ \sqrt(2) @f$.
90 static constexpr _RealType __root_2 = 1.4142135623730950488016887242096981L;
91 // Constant @f$ \sqrt(3) @f$.
92 static constexpr _RealType __root_3 = 1.7320508075688772935274463415058724L;
93 // Constant @f$ \sqrt(5) @f$.
94 static constexpr _RealType __root_5 = 2.2360679774997896964091736687312762L;
95 // Constant @f$ \sqrt(7) @f$.
96 static constexpr _RealType __root_7 = 2.6457513110645905905016157536392604L;
97 // Constant @f$ 1 / \sqrt(2) @f$.
98 static constexpr _RealType __one_div_root_2 = 0.7071067811865475244008443621048490L;
101 // And the template definitions for the constants.
102 template<typename _RealType>
103 constexpr _RealType __math_constants<_RealType>::__pi;
104 template<typename _RealType>
105 constexpr _RealType __math_constants<_RealType>::__pi_half;
106 template<typename _RealType>
107 constexpr _RealType __math_constants<_RealType>::__pi_third;
108 template<typename _RealType>
109 constexpr _RealType __math_constants<_RealType>::__pi_quarter;
110 template<typename _RealType>
111 constexpr _RealType __math_constants<_RealType>::__root_pi_div_2;
112 template<typename _RealType>
113 constexpr _RealType __math_constants<_RealType>::__one_div_pi;
114 template<typename _RealType>
115 constexpr _RealType __math_constants<_RealType>::__two_div_pi;
116 template<typename _RealType>
117 constexpr _RealType __math_constants<_RealType>::__two_div_root_pi;
118 template<typename _RealType>
119 constexpr _RealType __math_constants<_RealType>::__e;
120 template<typename _RealType>
121 constexpr _RealType __math_constants<_RealType>::__one_div_e;
122 template<typename _RealType>
123 constexpr _RealType __math_constants<_RealType>::__log2_e;
124 template<typename _RealType>
125 constexpr _RealType __math_constants<_RealType>::__log10_e;
126 template<typename _RealType>
127 constexpr _RealType __math_constants<_RealType>::__ln_2;
128 template<typename _RealType>
129 constexpr _RealType __math_constants<_RealType>::__ln_3;
130 template<typename _RealType>
131 constexpr _RealType __math_constants<_RealType>::__ln_10;
132 template<typename _RealType>
133 constexpr _RealType __math_constants<_RealType>::__gamma_e;
134 template<typename _RealType>
135 constexpr _RealType __math_constants<_RealType>::__phi;
136 template<typename _RealType>
137 constexpr _RealType __math_constants<_RealType>::__root_2;
138 template<typename _RealType>
139 constexpr _RealType __math_constants<_RealType>::__root_3;
140 template<typename _RealType>
141 constexpr _RealType __math_constants<_RealType>::__root_5;
142 template<typename _RealType>
143 constexpr _RealType __math_constants<_RealType>::__root_7;
144 template<typename _RealType>
145 constexpr _RealType __math_constants<_RealType>::__one_div_root_2;
147 _GLIBCXX_END_NAMESPACE_VERSION
148 } // namespace __gnu_cxx