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The C and C++ Include Header Files
cat -n /usr/include/c++/15/numbers
1 // <numbers> -*- C++ -*- 2 3 // Copyright (C) 2019-2025 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 46 namespace 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 56 namespace 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) && !defined(__CUDACC__) 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
