libstdc++: numeric Source File

libstdc++

ext/numeric
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1// Numeric extensions -*- C++ -*-
2
3// Copyright (C) 2002-2026 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/*
26 *
27 * Copyright (c) 1994
28 * Hewlett-Packard Company
29 *
30 * Permission to use, copy, modify, distribute and sell this software
31 * and its documentation for any purpose is hereby granted without fee,
32 * provided that the above copyright notice appear in all copies and
33 * that both that copyright notice and this permission notice appear
34 * in supporting documentation. Hewlett-Packard Company makes no
35 * representations about the suitability of this software for any
36 * purpose. It is provided "as is" without express or implied warranty.
37 *
38 *
39 * Copyright (c) 1996
40 * Silicon Graphics Computer Systems, Inc.
41 *
42 * Permission to use, copy, modify, distribute and sell this software
43 * and its documentation for any purpose is hereby granted without fee,
44 * provided that the above copyright notice appear in all copies and
45 * that both that copyright notice and this permission notice appear
46 * in supporting documentation. Silicon Graphics makes no
47 * representations about the suitability of this software for any
48 * purpose. It is provided "as is" without express or implied warranty.
49 */
50
51/** @file ext/numeric
52 * This file is a GNU extension to the Standard C++ Library (possibly
53 * containing extensions from the HP/SGI STL subset).
54 */
55
56#ifndef _EXT_NUMERIC
57#define _EXT_NUMERIC 1
58
59#ifdef _GLIBCXX_SYSHDR
60#pragma GCC system_header
61#endif
62
63#include <bits/requires_hosted.h> // GNU extensions are currently omitted
64
65#include <bits/concept_check.h>
66#include <numeric>
67
68#include <ext/functional> // For identity_element
69
70namespace __gnu_cxx _GLIBCXX_VISIBILITY(default)
71{
72_GLIBCXX_BEGIN_NAMESPACE_VERSION
73
74 // Returns __x ** __n, where __n >= 0. _Note that "multiplication"
75 // is required to be associative, but not necessarily commutative.
76 template<typename _Tp, typename _Integer, typename _MonoidOperation>
77 _Tp
78 __power(_Tp __x, _Integer __n, _MonoidOperation __monoid_op)
79 {
80 if (__n == 0)
81 return identity_element(__monoid_op);
82 else
83 {
84 while ((__n & 1) == 0)
85 {
86 __n >>= 1;
87 __x = __monoid_op(__x, __x);
88 }
89
90 _Tp __result = __x;
91 __n >>= 1;
92 while (__n != 0)
93 {
94 __x = __monoid_op(__x, __x);
95 if ((__n & 1) != 0)
96 __result = __monoid_op(__result, __x);
97 __n >>= 1;
98 }
99 return __result;
100 }
101 }
102
103 template<typename _Tp, typename _Integer>
104 inline _Tp
105 __power(_Tp __x, _Integer __n)
106 { return __power(__x, __n, std::multiplies<_Tp>()); }
107
108 /**
109 * This is an SGI extension.
110 * @ingroup SGIextensions
111 * @doctodo
112 */
113 // Alias for the internal name __power. Note that power is an extension,
114 // not part of the C++ standard.
115 template<typename _Tp, typename _Integer, typename _MonoidOperation>
116 inline _Tp
117 power(_Tp __x, _Integer __n, _MonoidOperation __monoid_op)
118 { return __power(__x, __n, __monoid_op); }
119
120 /**
121 * This is an SGI extension.
122 * @ingroup SGIextensions
123 * @doctodo
124 */
125 template<typename _Tp, typename _Integer>
126 inline _Tp
127 power(_Tp __x, _Integer __n)
128 { return __power(__x, __n); }
129
130#if __cplusplus >= 201103L
131 using std::iota;
132#else
133 /**
134 * This is an SGI extension.
135 * @ingroup SGIextensions
136 * @doctodo
137 */
138 // iota is not part of the standard until C++11. It is an extension.
139 template<typename _ForwardIter, typename _Tp>
140 void
141 iota(_ForwardIter __first, _ForwardIter __last, _Tp __value)
142 {
143 // concept requirements
144 __glibcxx_function_requires(_Mutable_ForwardIteratorConcept<_ForwardIter>)
145 __glibcxx_function_requires(_ConvertibleConcept<_Tp,
146 typename std::iterator_traits<_ForwardIter>::value_type>)
147
148 while (__first != __last)
149 *__first++ = __value++;
150 }
151#endif // C++11
152
153_GLIBCXX_END_NAMESPACE_VERSION
154} // namespace
155
156#endif
concept_check.h
requires_hosted.h
__gnu_cxx::power
_Tp power(_Tp __x, _Integer __n, _MonoidOperation __monoid_op)
Definition ext/numeric:117
std::iota
constexpr void iota(_ForwardIterator __first, _ForwardIterator __last, _Tp __value)
Create a range of sequentially increasing values.
Definition stl_numeric.h:87
__gnu_cxx
GNU extensions for public use.
__gnu_cxx::iota
constexpr void iota(_ForwardIterator __first, _ForwardIterator __last, _Tp __value)
Create a range of sequentially increasing values.
Definition stl_numeric.h:87
std::iterator_traits
Traits class for iterators.
Definition stl_iterator_base_types.h:185
functional
numeric