libstdc++
ext/cmath
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1 // Math extensions -*- C++ -*-
2 
3 // Copyright (C) 2013-2019 Free Software Foundation, Inc.
4 //
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)
9 // any later version.
10 
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.
15 
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.
19 
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/>.
24 
25 /** @file ext/cmath
26  * This file is a GNU extension to the Standard C++ Library.
27  */
28 
29 #ifndef _EXT_CMATH
30 #define _EXT_CMATH 1
31 
32 #pragma GCC system_header
33 
34 #if __cplusplus < 201103L
35 # include <bits/c++0x_warning.h>
36 #else
37 
38 #include <cmath>
39 #include <type_traits>
40 
41 namespace __gnu_cxx _GLIBCXX_VISIBILITY(default)
42 {
43 _GLIBCXX_BEGIN_NAMESPACE_VERSION
44 
45  // A class for math constants.
46  template<typename _RealType>
47  struct __math_constants
48  {
49  static_assert(std::is_floating_point<_RealType>::value,
50  "template argument not a floating point type");
51 
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$.
67  static constexpr _RealType __two_div_root_pi = 1.1283791670955125738961589031215452L;
68 
69  // Constant Euler's number @f$ 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$.
82  static constexpr _RealType __ln_10 = 2.3025850929940456840179914546843642L;
83 
84  // Constant Euler-Mascheroni @f$ \gamma_E @f$.
85  static constexpr _RealType __gamma_e = 0.5772156649015328606065120900824024L;
86  // Constant Golden Ratio @f$ \phi @f$.
87  static constexpr _RealType __phi = 1.6180339887498948482045868343656381L;
88 
89  // Constant @f$ \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;
99  };
100 
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;
146 
147 _GLIBCXX_END_NAMESPACE_VERSION
148 } // namespace __gnu_cxx
149 
150 #endif // C++11
151 
152 #endif // _EXT_CMATH