1 // The template and inlines for the -*- C++ -*- indirect_array class.
3 // Copyright (C) 1997, 1998, 1999, 2000, 2001, 2002, 2004, 2005, 2009, 2010
4 // Free Software Foundation, Inc.
6 // This file is part of the GNU ISO C++ Library. This library is free
7 // software; you can redistribute it and/or modify it under the
8 // terms of the GNU General Public License as published by the
9 // Free Software Foundation; either version 3, or (at your option)
12 // This library is distributed in the hope that it will be useful,
13 // but WITHOUT ANY WARRANTY; without even the implied warranty of
14 // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
15 // GNU General Public License for more details.
17 // Under Section 7 of GPL version 3, you are granted additional
18 // permissions described in the GCC Runtime Library Exception, version
19 // 3.1, as published by the Free Software Foundation.
21 // You should have received a copy of the GNU General Public License and
22 // a copy of the GCC Runtime Library Exception along with this program;
23 // see the files COPYING3 and COPYING.RUNTIME respectively. If not, see
24 // <http://www.gnu.org/licenses/>.
26 /** @file bits/indirect_array.h
27 * This is an internal header file, included by other library headers.
28 * Do not attempt to use it directly. @headername{valarray}
31 // Written by Gabriel Dos Reis <Gabriel.Dos-Reis@DPTMaths.ENS-Cachan.Fr>
33 #ifndef _INDIRECT_ARRAY_H
34 #define _INDIRECT_ARRAY_H 1
36 #pragma GCC system_header
38 namespace std
_GLIBCXX_VISIBILITY(default)
40 _GLIBCXX_BEGIN_NAMESPACE_VERSION
43 * @addtogroup numeric_arrays
48 * @brief Reference to arbitrary subset of an array.
50 * An indirect_array is a reference to the actual elements of an array
51 * specified by an ordered array of indices. The way to get an
52 * indirect_array is to call operator[](valarray<size_t>) on a valarray.
53 * The returned indirect_array then permits carrying operations out on the
54 * referenced subset of elements in the original valarray.
56 * For example, if an indirect_array is obtained using the array (4,2,0) as
57 * an argument, and then assigned to an array containing (1,2,3), then the
58 * underlying array will have array[0]==3, array[2]==2, and array[4]==1.
60 * @param Tp Element type.
66 typedef _Tp value_type
;
68 // _GLIBCXX_RESOLVE_LIB_DEFECTS
69 // 253. valarray helper functions are almost entirely useless
71 /// Copy constructor. Both slices refer to the same underlying array.
72 indirect_array(const indirect_array
&);
74 /// Assignment operator. Assigns elements to corresponding elements
76 indirect_array
& operator=(const indirect_array
&);
78 /// Assign slice elements to corresponding elements of @a v.
79 void operator=(const valarray
<_Tp
>&) const;
80 /// Multiply slice elements by corresponding elements of @a v.
81 void operator*=(const valarray
<_Tp
>&) const;
82 /// Divide slice elements by corresponding elements of @a v.
83 void operator/=(const valarray
<_Tp
>&) const;
84 /// Modulo slice elements by corresponding elements of @a v.
85 void operator%=(const valarray
<_Tp
>&) const;
86 /// Add corresponding elements of @a v to slice elements.
87 void operator+=(const valarray
<_Tp
>&) const;
88 /// Subtract corresponding elements of @a v from slice elements.
89 void operator-=(const valarray
<_Tp
>&) const;
90 /// Logical xor slice elements with corresponding elements of @a v.
91 void operator^=(const valarray
<_Tp
>&) const;
92 /// Logical and slice elements with corresponding elements of @a v.
93 void operator&=(const valarray
<_Tp
>&) const;
94 /// Logical or slice elements with corresponding elements of @a v.
95 void operator|=(const valarray
<_Tp
>&) const;
96 /// Left shift slice elements by corresponding elements of @a v.
97 void operator<<=(const valarray
<_Tp
>&) const;
98 /// Right shift slice elements by corresponding elements of @a v.
99 void operator>>=(const valarray
<_Tp
>&) const;
100 /// Assign all slice elements to @a t.
101 void operator= (const _Tp
&) const;
102 // ~indirect_array();
105 void operator=(const _Expr
<_Dom
, _Tp
>&) const;
107 void operator*=(const _Expr
<_Dom
, _Tp
>&) const;
109 void operator/=(const _Expr
<_Dom
, _Tp
>&) const;
111 void operator%=(const _Expr
<_Dom
, _Tp
>&) const;
113 void operator+=(const _Expr
<_Dom
, _Tp
>&) const;
115 void operator-=(const _Expr
<_Dom
, _Tp
>&) const;
117 void operator^=(const _Expr
<_Dom
, _Tp
>&) const;
119 void operator&=(const _Expr
<_Dom
, _Tp
>&) const;
121 void operator|=(const _Expr
<_Dom
, _Tp
>&) const;
123 void operator<<=(const _Expr
<_Dom
, _Tp
>&) const;
125 void operator>>=(const _Expr
<_Dom
, _Tp
>&) const;
128 /// Copy constructor. Both slices refer to the same underlying array.
129 indirect_array(_Array
<_Tp
>, size_t, _Array
<size_t>);
131 friend class valarray
<_Tp
>;
132 friend class gslice_array
<_Tp
>;
135 const _Array
<size_t> _M_index
;
136 const _Array
<_Tp
> _M_array
;
142 template<typename _Tp
>
144 indirect_array
<_Tp
>::indirect_array(const indirect_array
<_Tp
>& __a
)
145 : _M_sz(__a
._M_sz
), _M_index(__a
._M_index
), _M_array(__a
._M_array
) {}
147 template<typename _Tp
>
149 indirect_array
<_Tp
>::indirect_array(_Array
<_Tp
> __a
, size_t __s
,
151 : _M_sz(__s
), _M_index(__i
), _M_array(__a
) {}
153 template<typename _Tp
>
154 inline indirect_array
<_Tp
>&
155 indirect_array
<_Tp
>::operator=(const indirect_array
<_Tp
>& __a
)
157 std::__valarray_copy(__a
._M_array
, _M_sz
, __a
._M_index
, _M_array
,
162 template<typename _Tp
>
164 indirect_array
<_Tp
>::operator=(const _Tp
& __t
) const
165 { std::__valarray_fill(_M_array
, _M_index
, _M_sz
, __t
); }
167 template<typename _Tp
>
169 indirect_array
<_Tp
>::operator=(const valarray
<_Tp
>& __v
) const
170 { std::__valarray_copy(_Array
<_Tp
>(__v
), _M_sz
, _M_array
, _M_index
); }
172 template<typename _Tp
>
175 indirect_array
<_Tp
>::operator=(const _Expr
<_Dom
, _Tp
>& __e
) const
176 { std::__valarray_copy(__e
, _M_sz
, _M_array
, _M_index
); }
178 #undef _DEFINE_VALARRAY_OPERATOR
179 #define _DEFINE_VALARRAY_OPERATOR(_Op, _Name) \
180 template<typename _Tp> \
182 indirect_array<_Tp>::operator _Op##=(const valarray<_Tp>& __v) const\
184 _Array_augmented_##_Name(_M_array, _M_index, _Array<_Tp>(__v), _M_sz); \
187 template<typename _Tp> \
188 template<class _Dom> \
190 indirect_array<_Tp>::operator _Op##=(const _Expr<_Dom,_Tp>& __e) const\
192 _Array_augmented_##_Name(_M_array, _M_index, __e, _M_sz); \
195 _DEFINE_VALARRAY_OPERATOR(*, __multiplies
)
196 _DEFINE_VALARRAY_OPERATOR(/, __divides
)
197 _DEFINE_VALARRAY_OPERATOR(%, __modulus
)
198 _DEFINE_VALARRAY_OPERATOR(+, __plus
)
199 _DEFINE_VALARRAY_OPERATOR(-, __minus
)
200 _DEFINE_VALARRAY_OPERATOR(^, __bitwise_xor
)
201 _DEFINE_VALARRAY_OPERATOR(&, __bitwise_and
)
202 _DEFINE_VALARRAY_OPERATOR(|, __bitwise_or
)
203 _DEFINE_VALARRAY_OPERATOR(<<, __shift_left
)
204 _DEFINE_VALARRAY_OPERATOR(>>, __shift_right
)
206 #undef _DEFINE_VALARRAY_OPERATOR
208 // @} group numeric_arrays
210 _GLIBCXX_END_NAMESPACE_VERSION
213 #endif /* _INDIRECT_ARRAY_H */