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dft_tools/triqs/arrays/impl/assignment.hpp
Olivier Parcollet 1d929c1a91 arrays: add rebind const_view from view
- also add some static assert to forbid += and co on const_view
2013-10-22 21:29:27 +02:00

153 lines
8.3 KiB
C++

/*******************************************************************************
*
* TRIQS: a Toolbox for Research in Interacting Quantum Systems
*
* Copyright (C) 2011 by O. Parcollet
*
* TRIQS 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 of the License, or (at your option) any later
* version.
*
* TRIQS 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.
*
* You should have received a copy of the GNU General Public License along with
* TRIQS. If not, see <http://www.gnu.org/licenses/>.
*
******************************************************************************/
#ifndef TRIQS_ARRAYS_ASSIGN2_H_
#define TRIQS_ARRAYS_ASSIGN2_H_
#include "iterator_adapter.hpp"
#include "../indexmaps/cuboid/foreach.hpp"
#include "../storages/memcopy.hpp"
namespace triqs { namespace arrays {
namespace Tag {struct indexmap_storage_pair{}; }// defined here since needed below...
namespace assignment { template<typename LHS, typename RHS, char OP, typename Enable = void> struct impl; }
// puts the contents of RHS into LHS. LHS must be an indexmap_storage_pair
// it is specialized in various cases for optimisation.
template<typename LHS, typename RHS>
void triqs_arrays_assign_delegation (LHS & lhs, const RHS & rhs ) {
static_assert( !LHS::is_const, "Can not assign to a const view !");
assignment::impl<LHS, RHS, 'E'>(lhs, rhs).invoke();
}
template<typename LHS, typename RHS, char OP>
void triqs_arrays_compound_assign_delegation (LHS & lhs, const RHS & rhs, mpl::char_<OP> ) {
static_assert( !LHS::is_const, "Can not apply a compound operator to a const view !");
assignment::impl<LHS, RHS, OP>(lhs, rhs).invoke();
}
#define TRIQS_DEFINE_COMPOUND_OPERATORS(MYTYPE)\
template<typename RHS> MYTYPE & operator +=(RHS const & rhs) { triqs_arrays_compound_assign_delegation (*this,rhs, mpl::char_<'A'>()); return *this;}\
template<typename RHS> MYTYPE & operator -=(RHS const & rhs) { triqs_arrays_compound_assign_delegation (*this,rhs, mpl::char_<'S'>()); return *this;}\
template<typename RHS> MYTYPE & operator *=(RHS const & rhs) { triqs_arrays_compound_assign_delegation (*this,rhs, mpl::char_<'M'>()); return *this;}\
template<typename RHS> MYTYPE & operator /=(RHS const & rhs) { triqs_arrays_compound_assign_delegation (*this,rhs, mpl::char_<'D'>()); return *this;}
#define TRIQS_DELETE_COMPOUND_OPERATORS(MYTYPE)\
template<typename RHS> MYTYPE & operator +=(RHS const & rhs) = delete;\
template<typename RHS> MYTYPE & operator -=(RHS const & rhs) = delete;\
template<typename RHS> MYTYPE & operator *=(RHS const & rhs) = delete;\
template<typename RHS> MYTYPE & operator /=(RHS const & rhs) = delete;
// -------- IMPLEMENTATION ----------------------------
namespace assignment {
template<typename A,typename B, char OP> struct _ops_;
template<typename A,typename B> struct _ops_ <A,B,'E'> { static void invoke (A & a, B const & b) { a =b;} };
template<typename A,typename B> struct _ops_ <A,B,'A'> { static void invoke (A & a, B const & b) { a+=b;} };
template<typename A,typename B> struct _ops_ <A,B,'S'> { static void invoke (A & a, B const & b) { a-=b;} };
template<typename A,typename B> struct _ops_ <A,B,'M'> { static void invoke (A & a, B const & b) { a*=b;} };
template<typename A,typename B> struct _ops_ <A,B,'D'> { static void invoke (A & a, B const & b) { a/=b;} };
// RHS is considered to be an indexmap_storage_pair if it is one, ... except if it is the scalar type of hte LHS
// think about an Array< Array<T,2> > e.g.
template<class RHS,class LHS> struct is_isp :
std::integral_constant<bool, std::is_base_of<Tag::indexmap_storage_pair,RHS>::value && (!is_scalar_for<RHS,LHS>::value) > {};
#define TRIQS_REJECT_ASSIGN_TO_CONST \
static_assert( (!std::is_const<typename LHS::value_type>::value ), "Assignment : The value type of the LHS is const and can not be assigned to !");
#define TRIQS_REJECT_MATRIX_COMPOUND_MUL_DIV_NON_SCALAR\
static_assert( (!((OP=='M' || OP=='D') && MutableMatrix<LHS>::value && (!is_scalar_for<RHS,LHS>::value))),\
"*= and /= operator for non scalar RHS are deleted for a type modeling MutableMatrix (e.g. matrix, matrix_view) matrix, because this is ambiguous");
// ----------------- standard assignment for indexmap_storage_pair --------------------------------------------------
template<typename LHS, typename RHS, char OP>
struct impl<LHS,RHS, OP, ENABLE_IF(is_isp< RHS,LHS>) > {
TRIQS_REJECT_ASSIGN_TO_CONST;
TRIQS_REJECT_MATRIX_COMPOUND_MUL_DIV_NON_SCALAR;
typedef typename LHS::value_type value_type;
typedef typename LHS::indexmap_type indexmap_type;
LHS & lhs; const RHS & rhs;
typedef typename std::remove_cv<value_type>::type v_t;
impl(LHS & lhs_, const RHS & rhs_): lhs(lhs_), rhs(rhs_) {}
template<typename ... Args> void operator()(Args const & ... args) const {
_ops_<typename std::remove_cv<value_type>::type, typename RHS::value_type, OP>::invoke(lhs(args...), rhs(args...)) ;}
void invoke () {
#ifdef TRIQS_ARRAYS_DEBUG
if (!indexmaps::compatible_for_assignment(lhs.indexmap(), rhs.indexmap())) TRIQS_RUNTIME_ERROR<< "Size mismatch in operation "<<OP <<" : LHS "<< lhs << " \n RHS = "<< rhs;
#endif
if (( (OP=='E') && indexmaps::raw_copy_possible(lhs.indexmap(), rhs.indexmap()))) {
storages::memcopy(lhs.data_start(), rhs.data_start(), rhs.indexmap().domain().number_of_elements());
}
else { foreach(lhs,*this); }
}
};
// ----------------- assignment for expressions RHS --------------------------------------------------
template<typename LHS, typename RHS, char OP>
struct impl<LHS,RHS,OP, ENABLE_IFC( ImmutableCuboidArray<RHS>::value && (!is_scalar_for<RHS,LHS>::value) && (!is_isp<RHS,LHS>::value)) > {
TRIQS_REJECT_ASSIGN_TO_CONST;
TRIQS_REJECT_MATRIX_COMPOUND_MUL_DIV_NON_SCALAR;
typedef typename LHS::value_type value_type;
LHS & lhs; const RHS & rhs;
impl(LHS & lhs_, const RHS & rhs_): lhs(lhs_), rhs(rhs_) {} //, p(*(lhs_.data_start())) {}
template<typename ... Args> void operator()(Args const & ... args) const { _ops_<value_type, typename RHS::value_type, OP>::invoke(lhs(args...),rhs(args...));}
void invoke() { foreach(lhs,*this); }
};
// ----------------- assignment for scalar RHS, except some matrix case --------------------------------------------------
template<typename LHS, typename RHS, char OP>
struct impl<LHS,RHS,OP, ENABLE_IFC(is_scalar_for<RHS,LHS>::value && (!(MutableMatrix<LHS>::value && (OP=='A'||OP=='S'||OP=='E') ))) >{
TRIQS_REJECT_ASSIGN_TO_CONST;
typedef typename LHS::value_type value_type;
LHS & lhs; const RHS & rhs;
impl(LHS & lhs_, const RHS & rhs_): lhs(lhs_), rhs(rhs_){}//, p(*(lhs_.data_start())) {}
template<typename ... Args> void operator()(Args const & ...args) const {_ops_<value_type, RHS, OP>::invoke(lhs(args...), rhs);}
void invoke() { foreach(lhs,*this); }
};
// ----------------- assignment for scalar RHS for Matrices --------------------------------------------------
template <typename T, int R> bool kronecker(mini_vector<T,R> const & key) { return ( (R==2) && (key[0]==key[1]));}
template <typename T> bool kronecker(T const & x0, T const & x1) { return ( (x0==x1));}
// Specialisation for Matrix Classes : scalar is a unity matrix, and operation is E, A, S, but NOT M, D
template<typename LHS, typename RHS, char OP>
struct impl<LHS,RHS,OP, ENABLE_IFC(is_scalar_for<RHS,LHS>::value && (MutableMatrix<LHS>::value && (OP=='A'||OP=='S'||OP=='E')))> {
TRIQS_REJECT_ASSIGN_TO_CONST;
typedef typename LHS::value_type value_type;
LHS & lhs; const RHS & rhs;
impl(LHS & lhs_, const RHS & rhs_): lhs(lhs_), rhs(rhs_){} //, p(*(lhs_.data_start())) {}
template<typename ... Args>
void operator()(Args const & ... args) const {_ops_<value_type, RHS, OP>::invoke(lhs(args...), (kronecker(args...) ? rhs : RHS()));}
void invoke() { foreach(lhs,*this); }
};
#undef TRIQS_REJECT_MATRIX_COMPOUND_MUL_DIV_NON_SCALAR
#undef TRIQS_REJECT_ASSIGN_TO_CONST
}// assignment
}}//namespace triqs::arrays
#endif