1// <numbers> -*- C++ -*-
2
3// Copyright (C) 2019-2020 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 include/numbers
26 *  This is a Standard C++ Library header.
27 */
28
29#ifndef _GLIBCXX_NUMBERS
30#define _GLIBCXX_NUMBERS 1
31
32#pragma GCC system_header
33
34#if __cplusplus > 201703L
35
36#include <type_traits>
37
38namespace std _GLIBCXX_VISIBILITY(default)
39{
40_GLIBCXX_BEGIN_NAMESPACE_VERSION
41
42/** @defgroup math_constants Mathematical constants
43 *  @ingroup numerics
44 *  @{
45 */
46
47/// Namespace for mathematical constants
48namespace numbers
49{
50#define __cpp_lib_math_constants 201907L
51
52  /// @cond undoc
53  template<typename _Tp>
54    using _Enable_if_floating = enable_if_t<is_floating_point_v<_Tp>, _Tp>;
55  /// @endcond
56
57  /// e
58  template<typename _Tp>
59    inline constexpr _Tp e_v
60      = _Enable_if_floating<_Tp>(2.718281828459045235360287471352662498L);
61
62  /// log_2 e
63  template<typename _Tp>
64    inline constexpr _Tp log2e_v
65      = _Enable_if_floating<_Tp>(1.442695040888963407359924681001892137L);
66
67  /// log_10 e
68  template<typename _Tp>
69    inline constexpr _Tp log10e_v
70      = _Enable_if_floating<_Tp>(0.434294481903251827651128918916605082L);
71
72  /// pi
73  template<typename _Tp>
74    inline constexpr _Tp pi_v
75      = _Enable_if_floating<_Tp>(3.141592653589793238462643383279502884L);
76
77  /// 1/pi
78  template<typename _Tp>
79    inline constexpr _Tp inv_pi_v
80      = _Enable_if_floating<_Tp>(0.318309886183790671537767526745028724L);
81
82  /// 1/sqrt(pi)
83  template<typename _Tp>
84    inline constexpr _Tp inv_sqrtpi_v
85      = _Enable_if_floating<_Tp>(0.564189583547756286948079451560772586L);
86
87  /// log_e 2
88  template<typename _Tp>
89    inline constexpr _Tp ln2_v
90      = _Enable_if_floating<_Tp>(0.693147180559945309417232121458176568L);
91
92  /// log_e 10
93  template<typename _Tp>
94    inline constexpr _Tp ln10_v
95      = _Enable_if_floating<_Tp>(2.302585092994045684017991454684364208L);
96
97  /// sqrt(2)
98  template<typename _Tp>
99    inline constexpr _Tp sqrt2_v
100      = _Enable_if_floating<_Tp>(1.414213562373095048801688724209698079L);
101
102  /// sqrt(3)
103  template<typename _Tp>
104    inline constexpr _Tp sqrt3_v
105      = _Enable_if_floating<_Tp>(1.732050807568877293527446341505872367L);
106
107  /// 1/sqrt(3)
108  template<typename _Tp>
109    inline constexpr _Tp inv_sqrt3_v
110      = _Enable_if_floating<_Tp>(0.577350269189625764509148780501957456L);
111
112  /// The Euler-Mascheroni constant
113  template<typename _Tp>
114    inline constexpr _Tp egamma_v
115      = _Enable_if_floating<_Tp>(0.577215664901532860606512090082402431L);
116
117  /// The golden ratio, (1+sqrt(5))/2
118  template<typename _Tp>
119    inline constexpr _Tp phi_v
120      = _Enable_if_floating<_Tp>(1.618033988749894848204586834365638118L);
121
122  inline constexpr double e = e_v<double>;
123  inline constexpr double log2e = log2e_v<double>;
124  inline constexpr double log10e = log10e_v<double>;
125  inline constexpr double pi = pi_v<double>;
126  inline constexpr double inv_pi = inv_pi_v<double>;
127  inline constexpr double inv_sqrtpi = inv_sqrtpi_v<double>;
128  inline constexpr double ln2 = ln2_v<double>;
129  inline constexpr double ln10 = ln10_v<double>;
130  inline constexpr double sqrt2 = sqrt2_v<double>;
131  inline constexpr double sqrt3 = sqrt3_v<double>;
132  inline constexpr double inv_sqrt3 = inv_sqrt3_v<double>;
133  inline constexpr double egamma = egamma_v<double>;
134  inline constexpr double phi = phi_v<double>;
135
136#if !defined(__STRICT_ANSI__) && defined(_GLIBCXX_USE_FLOAT128)
137  template<>
138    inline constexpr __float128 e_v<__float128>
139      = 2.718281828459045235360287471352662498Q;
140
141  /// log_2 e
142  template<>
143    inline constexpr __float128 log2e_v<__float128>
144      = 1.442695040888963407359924681001892137Q;
145
146  /// log_10 e
147  template<>
148    inline constexpr __float128 log10e_v<__float128>
149      = 0.434294481903251827651128918916605082Q;
150
151  /// pi
152  template<>
153    inline constexpr __float128 pi_v<__float128>
154      = 3.141592653589793238462643383279502884Q;
155
156  /// 1/pi
157  template<>
158    inline constexpr __float128 inv_pi_v<__float128>
159      = 0.318309886183790671537767526745028724Q;
160
161  /// 1/sqrt(pi)
162  template<>
163    inline constexpr __float128 inv_sqrtpi_v<__float128>
164      = 0.564189583547756286948079451560772586Q;
165
166  /// log_e 2
167  template<>
168    inline constexpr __float128 ln2_v<__float128>
169      = 0.693147180559945309417232121458176568Q;
170
171  /// log_e 10
172  template<>
173    inline constexpr __float128 ln10_v<__float128>
174      = 2.302585092994045684017991454684364208Q;
175
176  /// sqrt(2)
177  template<>
178    inline constexpr __float128 sqrt2_v<__float128>
179      = 1.414213562373095048801688724209698079Q;
180
181  /// sqrt(3)
182  template<>
183    inline constexpr __float128 sqrt3_v<__float128>
184      = 1.732050807568877293527446341505872367Q;
185
186  /// 1/sqrt(3)
187  template<>
188    inline constexpr __float128 inv_sqrt3_v<__float128>
189      = 0.577350269189625764509148780501957456Q;
190
191  /// The Euler-Mascheroni constant
192  template<>
193    inline constexpr __float128 egamma_v<__float128>
194      = 0.577215664901532860606512090082402431Q;
195
196  /// The golden ratio, (1+sqrt(5))/2
197  template<>
198    inline constexpr __float128 phi_v<__float128>
199      = 1.618033988749894848204586834365638118Q;
200#endif // USE_FLOAT128
201
202} // namespace numbers
203/// @}
204_GLIBCXX_END_NAMESPACE_VERSION
205} // namespace std
206
207#endif // C++20
208#endif // _GLIBCXX_NUMBERS
209