libstdc++
ext/numeric
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1 // Numeric extensions -*- C++ -*-
2 
3 // Copyright (C) 2002-2017 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
GNU extensions for public use.
void iota(_ForwardIterator __first, _ForwardIterator __last, _Tp __value)
Create a range of sequentially increasing values.
Definition: stl_numeric.h:82
One of the math functors.
Definition: stl_function.h:153
_Tp power(_Tp __x, _Integer __n, _MonoidOperation __monoid_op)
Definition: ext/numeric:113