libstdc++

ext/numeric
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1 // Numeric extensions -*- C++ -*-
2
3 // Copyright (C) 2002-2013 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 #pragma GCC system_header
60
61 #include <bits/concept_check.h>
62 #include <numeric>
63
64 #include <ext/functional> // For identity_element
65
66 namespace __gnu_cxx _GLIBCXX_VISIBILITY(default)
67 {
68 _GLIBCXX_BEGIN_NAMESPACE_VERSION
69
70 // Returns __x ** __n, where __n >= 0. _Note that "multiplication"
71 // is required to be associative, but not necessarily commutative.
72 template<typename _Tp, typename _Integer, typename _MonoidOperation>
73 _Tp
74 __power(_Tp __x, _Integer __n, _MonoidOperation __monoid_op)
75 {
76 if (__n == 0)
77 return identity_element(__monoid_op);
78 else
79 {
80 while ((__n & 1) == 0)
81 {
82 __n >>= 1;
83 __x = __monoid_op(__x, __x);
84 }
85
86 _Tp __result = __x;
87 __n >>= 1;
88 while (__n != 0)
89 {
90 __x = __monoid_op(__x, __x);
91 if ((__n & 1) != 0)
92 __result = __monoid_op(__result, __x);
93 __n >>= 1;
94 }
95 return __result;
96 }
97 }
98
99 template<typename _Tp, typename _Integer>
100 inline _Tp
101 __power(_Tp __x, _Integer __n)
102 { return __power(__x, __n, std::multiplies<_Tp>()); }
103
104 /**
105 * This is an SGI extension.
106 * @ingroup SGIextensions
107 * @doctodo
108 */
109 // Alias for the internal name __power. Note that power is an extension,
110 // not part of the C++ standard.
111 template<typename _Tp, typename _Integer, typename _MonoidOperation>
112 inline _Tp
113 power(_Tp __x, _Integer __n, _MonoidOperation __monoid_op)
114 { return __power(__x, __n, __monoid_op); }
115
116 /**
117 * This is an SGI extension.
118 * @ingroup SGIextensions
119 * @doctodo
120 */
121 template<typename _Tp, typename _Integer>
122 inline _Tp
123 power(_Tp __x, _Integer __n)
124 { return __power(__x, __n); }
125
126 #if __cplusplus >= 201103L
127 using std::iota;
128 #else
129 /**
130 * This is an SGI extension.
131 * @ingroup SGIextensions
132 * @doctodo
133 */
134 // iota is not part of the C++ standard. It is an extension.
135 template<typename _ForwardIter, typename _Tp>
136 void
137 iota(_ForwardIter __first, _ForwardIter __last, _Tp __value)
138 {
139 // concept requirements
140 __glibcxx_function_requires(_Mutable_ForwardIteratorConcept<_ForwardIter>)
141 __glibcxx_function_requires(_ConvertibleConcept<_Tp,
142 typename std::iterator_traits<_ForwardIter>::value_type>)
143
144 while (__first != __last)
145 *__first++ = __value++;
146 }
147 #endif // C++11
148
149 _GLIBCXX_END_NAMESPACE_VERSION
150 } // namespace
151
152 #endif