gslice_array.h
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// The template and inlines for the -*- C++ -*- gslice_array class.
// Copyright (C) 1997-2013 Free Software Foundation, Inc.
//
// This file is part of the GNU ISO C++ Library. This library is free
// software; you can redistribute it and/or modify it under the
// terms of the GNU General Public License as published by the
// Free Software Foundation; either version 3, or (at your option)
// any later version.
// This library is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
// GNU General Public License for more details.
// Under Section 7 of GPL version 3, you are granted additional
// permissions described in the GCC Runtime Library Exception, version
// 3.1, as published by the Free Software Foundation.
// You should have received a copy of the GNU General Public License and
// a copy of the GCC Runtime Library Exception along with this program;
// see the files COPYING3 and COPYING.RUNTIME respectively. If not, see
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/** @file bits/gslice_array.h
* This is an internal header file, included by other library headers.
* Do not attempt to use it directly. @headername{valarray}
*/
// Written by Gabriel Dos Reis <Gabriel.Dos-Reis@DPTMaths.ENS-Cachan.Fr>
#ifndef _GSLICE_ARRAY_H
#define _GSLICE_ARRAY_H 1
#pragma GCC system_header
namespace std _GLIBCXX_VISIBILITY(default)
{
_GLIBCXX_BEGIN_NAMESPACE_VERSION
/**
* @addtogroup numeric_arrays
* @{
*/
/**
* @brief Reference to multi-dimensional subset of an array.
*
* A gslice_array is a reference to the actual elements of an array
* specified by a gslice. The way to get a gslice_array is to call
* operator[](gslice) on a valarray. The returned gslice_array then
* permits carrying operations out on the referenced subset of elements in
* the original valarray. For example, operator+=(valarray) will add
* values to the subset of elements in the underlying valarray this
* gslice_array refers to.
*
* @param Tp Element type.
*/
template<typename _Tp>
class gslice_array
{
public:
typedef _Tp value_type;
// _GLIBCXX_RESOLVE_LIB_DEFECTS
// 253. valarray helper functions are almost entirely useless
/// Copy constructor. Both slices refer to the same underlying array.
gslice_array(const gslice_array&);
/// Assignment operator. Assigns slice elements to corresponding
/// elements of @a a.
gslice_array& operator=(const gslice_array&);
/// Assign slice elements to corresponding elements of @a v.
void operator=(const valarray<_Tp>&) const;
/// Multiply slice elements by corresponding elements of @a v.
void operator*=(const valarray<_Tp>&) const;
/// Divide slice elements by corresponding elements of @a v.
void operator/=(const valarray<_Tp>&) const;
/// Modulo slice elements by corresponding elements of @a v.
void operator%=(const valarray<_Tp>&) const;
/// Add corresponding elements of @a v to slice elements.
void operator+=(const valarray<_Tp>&) const;
/// Subtract corresponding elements of @a v from slice elements.
void operator-=(const valarray<_Tp>&) const;
/// Logical xor slice elements with corresponding elements of @a v.
void operator^=(const valarray<_Tp>&) const;
/// Logical and slice elements with corresponding elements of @a v.
void operator&=(const valarray<_Tp>&) const;
/// Logical or slice elements with corresponding elements of @a v.
void operator|=(const valarray<_Tp>&) const;
/// Left shift slice elements by corresponding elements of @a v.
void operator<<=(const valarray<_Tp>&) const;
/// Right shift slice elements by corresponding elements of @a v.
void operator>>=(const valarray<_Tp>&) const;
/// Assign all slice elements to @a t.
void operator=(const _Tp&) const;
template<class _Dom>
void operator=(const _Expr<_Dom, _Tp>&) const;
template<class _Dom>
void operator*=(const _Expr<_Dom, _Tp>&) const;
template<class _Dom>
void operator/=(const _Expr<_Dom, _Tp>&) const;
template<class _Dom>
void operator%=(const _Expr<_Dom, _Tp>&) const;
template<class _Dom>
void operator+=(const _Expr<_Dom, _Tp>&) const;
template<class _Dom>
void operator-=(const _Expr<_Dom, _Tp>&) const;
template<class _Dom>
void operator^=(const _Expr<_Dom, _Tp>&) const;
template<class _Dom>
void operator&=(const _Expr<_Dom, _Tp>&) const;
template<class _Dom>
void operator|=(const _Expr<_Dom, _Tp>&) const;
template<class _Dom>
void operator<<=(const _Expr<_Dom, _Tp>&) const;
template<class _Dom>
void operator>>=(const _Expr<_Dom, _Tp>&) const;
private:
_Array<_Tp> _M_array;
const valarray<size_t>& _M_index;
friend class valarray<_Tp>;
gslice_array(_Array<_Tp>, const valarray<size_t>&);
// not implemented
gslice_array();
};
template<typename _Tp>
inline
gslice_array<_Tp>::gslice_array(_Array<_Tp> __a,
const valarray<size_t>& __i)
: _M_array(__a), _M_index(__i) {}
template<typename _Tp>
inline
gslice_array<_Tp>::gslice_array(const gslice_array<_Tp>& __a)
: _M_array(__a._M_array), _M_index(__a._M_index) {}
template<typename _Tp>
inline gslice_array<_Tp>&
gslice_array<_Tp>::operator=(const gslice_array<_Tp>& __a)
{
std::__valarray_copy(_Array<_Tp>(__a._M_array),
_Array<size_t>(__a._M_index), _M_index.size(),
_M_array, _Array<size_t>(_M_index));
return *this;
}
template<typename _Tp>
inline void
gslice_array<_Tp>::operator=(const _Tp& __t) const
{
std::__valarray_fill(_M_array, _Array<size_t>(_M_index),
_M_index.size(), __t);
}
template<typename _Tp>
inline void
gslice_array<_Tp>::operator=(const valarray<_Tp>& __v) const
{
std::__valarray_copy(_Array<_Tp>(__v), __v.size(),
_M_array, _Array<size_t>(_M_index));
}
template<typename _Tp>
template<class _Dom>
inline void
gslice_array<_Tp>::operator=(const _Expr<_Dom, _Tp>& __e) const
{
std::__valarray_copy (__e, _M_index.size(), _M_array,
_Array<size_t>(_M_index));
}
#undef _DEFINE_VALARRAY_OPERATOR
#define _DEFINE_VALARRAY_OPERATOR(_Op, _Name) \
template<typename _Tp> \
inline void \
gslice_array<_Tp>::operator _Op##=(const valarray<_Tp>& __v) const \
{ \
_Array_augmented_##_Name(_M_array, _Array<size_t>(_M_index), \
_Array<_Tp>(__v), __v.size()); \
} \
\
template<typename _Tp> \
template<class _Dom> \
inline void \
gslice_array<_Tp>::operator _Op##= (const _Expr<_Dom, _Tp>& __e) const\
{ \
_Array_augmented_##_Name(_M_array, _Array<size_t>(_M_index), __e,\
_M_index.size()); \
}
_DEFINE_VALARRAY_OPERATOR(*, __multiplies)
_DEFINE_VALARRAY_OPERATOR(/, __divides)
_DEFINE_VALARRAY_OPERATOR(%, __modulus)
_DEFINE_VALARRAY_OPERATOR(+, __plus)
_DEFINE_VALARRAY_OPERATOR(-, __minus)
_DEFINE_VALARRAY_OPERATOR(^, __bitwise_xor)
_DEFINE_VALARRAY_OPERATOR(&, __bitwise_and)
_DEFINE_VALARRAY_OPERATOR(|, __bitwise_or)
_DEFINE_VALARRAY_OPERATOR(<<, __shift_left)
_DEFINE_VALARRAY_OPERATOR(>>, __shift_right)
#undef _DEFINE_VALARRAY_OPERATOR
// @} group numeric_arrays
_GLIBCXX_END_NAMESPACE_VERSION
} // namespace
#endif /* _GSLICE_ARRAY_H */