libstdc++: numbers Source File

libstdc++

numbers
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1// <numbers> -*- C++ -*-
2
3// Copyright (C) 2019-2026 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#ifdef _GLIBCXX_SYSHDR
33#pragma GCC system_header
34#endif
35
36#define __glibcxx_want_math_constants
37#include <bits/version.h>
38
39#ifdef __cpp_lib_math_constants // C++ >= 20
40
41#include <type_traits>
42
43#pragma GCC diagnostic push
44#pragma GCC diagnostic ignored "-Wpedantic" // Q extension
45
46namespace std _GLIBCXX_VISIBILITY(default)
47{
48_GLIBCXX_BEGIN_NAMESPACE_VERSION
49
50/** @defgroup math_constants Mathematical constants
51 * @ingroup numerics
52 * @{
53 */
54
55/// Namespace for mathematical constants
56namespace numbers
57{
58
59 /// @cond undocumented
60 template<typename _Tp>
61 using _Enable_if_floating = enable_if_t<is_floating_point_v<_Tp>, _Tp>;
62 /// @endcond
63
64 /// e
65 template<typename _Tp>
66 inline constexpr _Tp e_v
67 = _Enable_if_floating<_Tp>(2.718281828459045235360287471352662498L);
68
69 /// log_2 e
70 template<typename _Tp>
71 inline constexpr _Tp log2e_v
72 = _Enable_if_floating<_Tp>(1.442695040888963407359924681001892137L);
73
74 /// log_10 e
75 template<typename _Tp>
76 inline constexpr _Tp log10e_v
77 = _Enable_if_floating<_Tp>(0.434294481903251827651128918916605082L);
78
79 /// pi
80 template<typename _Tp>
81 inline constexpr _Tp pi_v
82 = _Enable_if_floating<_Tp>(3.141592653589793238462643383279502884L);
83
84 /// 1/pi
85 template<typename _Tp>
86 inline constexpr _Tp inv_pi_v
87 = _Enable_if_floating<_Tp>(0.318309886183790671537767526745028724L);
88
89 /// 1/sqrt(pi)
90 template<typename _Tp>
91 inline constexpr _Tp inv_sqrtpi_v
92 = _Enable_if_floating<_Tp>(0.564189583547756286948079451560772586L);
93
94 /// log_e 2
95 template<typename _Tp>
96 inline constexpr _Tp ln2_v
97 = _Enable_if_floating<_Tp>(0.693147180559945309417232121458176568L);
98
99 /// log_e 10
100 template<typename _Tp>
101 inline constexpr _Tp ln10_v
102 = _Enable_if_floating<_Tp>(2.302585092994045684017991454684364208L);
103
104 /// sqrt(2)
105 template<typename _Tp>
106 inline constexpr _Tp sqrt2_v
107 = _Enable_if_floating<_Tp>(1.414213562373095048801688724209698079L);
108
109 /// sqrt(3)
110 template<typename _Tp>
111 inline constexpr _Tp sqrt3_v
112 = _Enable_if_floating<_Tp>(1.732050807568877293527446341505872367L);
113
114 /// 1/sqrt(3)
115 template<typename _Tp>
116 inline constexpr _Tp inv_sqrt3_v
117 = _Enable_if_floating<_Tp>(0.577350269189625764509148780501957456L);
118
119 /// The Euler-Mascheroni constant
120 template<typename _Tp>
121 inline constexpr _Tp egamma_v
122 = _Enable_if_floating<_Tp>(0.577215664901532860606512090082402431L);
123
124 /// The golden ratio, (1+sqrt(5))/2
125 template<typename _Tp>
126 inline constexpr _Tp phi_v
127 = _Enable_if_floating<_Tp>(1.618033988749894848204586834365638118L);
128
129 inline constexpr double e = e_v<double>;
130 inline constexpr double log2e = log2e_v<double>;
131 inline constexpr double log10e = log10e_v<double>;
132 inline constexpr double pi = pi_v<double>;
133 inline constexpr double inv_pi = inv_pi_v<double>;
134 inline constexpr double inv_sqrtpi = inv_sqrtpi_v<double>;
135 inline constexpr double ln2 = ln2_v<double>;
136 inline constexpr double ln10 = ln10_v<double>;
137 inline constexpr double sqrt2 = sqrt2_v<double>;
138 inline constexpr double sqrt3 = sqrt3_v<double>;
139 inline constexpr double inv_sqrt3 = inv_sqrt3_v<double>;
140 inline constexpr double egamma = egamma_v<double>;
141 inline constexpr double phi = phi_v<double>;
142
143#define __glibcxx_numbers(TYPE, SUFFIX) \
144 /* e */ \
145 template<> \
146 inline constexpr TYPE e_v<TYPE> \
147 = 2.718281828459045235360287471352662498##SUFFIX; \
148 \
149 /* log_2 e */ \
150 template<> \
151 inline constexpr TYPE log2e_v<TYPE> \
152 = 1.442695040888963407359924681001892137##SUFFIX; \
153 \
154 /* log_10 e */ \
155 template<> \
156 inline constexpr TYPE log10e_v<TYPE> \
157 = 0.434294481903251827651128918916605082##SUFFIX; \
158 \
159 /* pi */ \
160 template<> \
161 inline constexpr TYPE pi_v<TYPE> \
162 = 3.141592653589793238462643383279502884##SUFFIX; \
163 \
164 /* 1/pi */ \
165 template<> \
166 inline constexpr TYPE inv_pi_v<TYPE> \
167 = 0.318309886183790671537767526745028724##SUFFIX; \
168 \
169 /* 1/sqrt(pi) */ \
170 template<> \
171 inline constexpr TYPE inv_sqrtpi_v<TYPE> \
172 = 0.564189583547756286948079451560772586##SUFFIX; \
173 \
174 /* log_e 2 */ \
175 template<> \
176 inline constexpr TYPE ln2_v<TYPE> \
177 = 0.693147180559945309417232121458176568##SUFFIX; \
178 \
179 /* log_e 10 */ \
180 template<> \
181 inline constexpr TYPE ln10_v<TYPE> \
182 = 2.302585092994045684017991454684364208##SUFFIX; \
183 \
184 /* sqrt(2) */ \
185 template<> \
186 inline constexpr TYPE sqrt2_v<TYPE> \
187 = 1.414213562373095048801688724209698079##SUFFIX; \
188 \
189 /* sqrt(3) */ \
190 template<> \
191 inline constexpr TYPE sqrt3_v<TYPE> \
192 = 1.732050807568877293527446341505872367##SUFFIX; \
193 \
194 /* 1/sqrt(3) */ \
195 template<> \
196 inline constexpr TYPE inv_sqrt3_v<TYPE> \
197 = 0.577350269189625764509148780501957456##SUFFIX; \
198 \
199 /* The Euler-Mascheroni constant */ \
200 template<> \
201 inline constexpr TYPE egamma_v<TYPE> \
202 = 0.577215664901532860606512090082402431##SUFFIX; \
203 \
204 /* The golden ratio, (1+sqrt(5))/2 */ \
205 template<> \
206 inline constexpr TYPE phi_v<TYPE> \
207 = 1.618033988749894848204586834365638118##SUFFIX
208
209#ifdef __STDCPP_FLOAT16_T__
210__glibcxx_numbers (_Float16, F16);
211#endif
212
213#ifdef __STDCPP_FLOAT32_T__
214__glibcxx_numbers (_Float32, F32);
215#endif
216
217#ifdef __STDCPP_FLOAT64_T__
218__glibcxx_numbers (_Float64, F64);
219#endif
220
221#ifdef __STDCPP_FLOAT128_T__
222__glibcxx_numbers (_Float128, F128);
223#endif
224
225#ifdef __STDCPP_BFLOAT128_T__
226__glibcxx_numbers (__gnu_cxx::__bfloat16_t, BF16);
227#endif
228
229#if !defined(__STRICT_ANSI__) && defined(_GLIBCXX_USE_FLOAT128)
230__glibcxx_numbers (__float128, Q);
231#endif // USE_FLOAT128
232
233#undef __glibcxx_numbers
234
235} // namespace numbers
236/// @}
237_GLIBCXX_END_NAMESPACE_VERSION
238} // namespace std
239
240#pragma GCC diagnostic pop
241
242#endif // __cpp_lib_math_constants
243#endif // _GLIBCXX_NUMBERS
type_traits
version.h
std
ISO C++ entities toplevel namespace is std.