206 lines
6.6 KiB
C++
206 lines
6.6 KiB
C++
/* -*- C++ -*- ------------------------------------------------------------
|
|
|
|
Copyright (c) 2007 Jesse Anders and Demian Nave http://cmldev.net/
|
|
|
|
The Configurable Math Library (CML) is distributed under the terms of the
|
|
Boost Software License, v1.0 (see cml/LICENSE for details).
|
|
|
|
*-----------------------------------------------------------------------*/
|
|
/** @file
|
|
* @brief Multiply two matrices.
|
|
*
|
|
* @todo Does it make sense to put mat-mat multiplication as a node into the
|
|
* expression tree?
|
|
*
|
|
* @internal This does not need to return an expression type, since the
|
|
* temporary generation for the matrix result is handled automatically by the
|
|
* compiler. i.e. when used in an expression, the result is automatically
|
|
* included in the expression tree as a temporary by the compiler.
|
|
*/
|
|
|
|
#ifndef matrix_mul_h
|
|
#define matrix_mul_h
|
|
|
|
#include <cml/et/size_checking.h>
|
|
#include <cml/matrix/matrix_expr.h>
|
|
|
|
/* This is used below to create a more meaningful compile-time error when
|
|
* mul is not provided with matrix or MatrixExpr arguments:
|
|
*/
|
|
struct mul_expects_matrix_args_error;
|
|
|
|
/* This is used below to create a more meaningful compile-time error when
|
|
* fixed-size arguments to mul() have the wrong size:
|
|
*/
|
|
struct mul_expressions_have_wrong_size_error;
|
|
|
|
namespace cml {
|
|
namespace detail {
|
|
|
|
/** Verify the sizes of the argument matrices for matrix multiplication.
|
|
*
|
|
* @returns a matrix_size containing the size of the resulting matrix.
|
|
*/
|
|
template<typename LeftT, typename RightT> inline matrix_size
|
|
MatMulCheckedSize(const LeftT&, const RightT&, fixed_size_tag)
|
|
{
|
|
CML_STATIC_REQUIRE_M(
|
|
((size_t)LeftT::array_cols == (size_t)RightT::array_rows),
|
|
mul_expressions_have_wrong_size_error);
|
|
return matrix_size(LeftT::array_rows,RightT::array_cols);
|
|
}
|
|
|
|
/** Verify the sizes of the argument matrices for matrix multiplication.
|
|
*
|
|
* @returns a matrix_size containing the size of the resulting matrix.
|
|
*/
|
|
template<typename LeftT, typename RightT> inline matrix_size
|
|
MatMulCheckedSize(const LeftT& left, const RightT& right, dynamic_size_tag)
|
|
{
|
|
matrix_size left_N = left.size(), right_N = right.size();
|
|
et::GetCheckedSize<LeftT,RightT,dynamic_size_tag>()
|
|
.equal_or_fail(left_N.second, right_N.first); /* cols,rows */
|
|
return matrix_size(left_N.first, right_N.second); /* rows,cols */
|
|
}
|
|
|
|
|
|
/** Matrix multiplication.
|
|
*
|
|
* Computes C = A x B (O(N^3), non-blocked algorithm).
|
|
*/
|
|
template<class LeftT, class RightT>
|
|
inline typename et::MatrixPromote<
|
|
typename et::ExprTraits<LeftT>::result_type,
|
|
typename et::ExprTraits<RightT>::result_type
|
|
>::temporary_type
|
|
mul(const LeftT& left, const RightT& right)
|
|
{
|
|
/* Shorthand: */
|
|
typedef et::ExprTraits<LeftT> left_traits;
|
|
typedef et::ExprTraits<RightT> right_traits;
|
|
typedef typename left_traits::result_type left_result;
|
|
typedef typename right_traits::result_type right_result;
|
|
|
|
/* First, require matrix expressions: */
|
|
CML_STATIC_REQUIRE_M(
|
|
(et::MatrixExpressions<LeftT,RightT>::is_true),
|
|
mul_expects_matrix_args_error);
|
|
/* Note: parens are required here so that the preprocessor ignores the
|
|
* commas.
|
|
*/
|
|
|
|
/* Deduce size type to ensure that a run-time check is performed if
|
|
* necessary:
|
|
*/
|
|
typedef typename et::MatrixPromote<
|
|
typename left_traits::result_type,
|
|
typename right_traits::result_type
|
|
>::type result_type;
|
|
typedef typename result_type::size_tag size_tag;
|
|
|
|
/* Require that left has the same number of columns as right has rows.
|
|
* This automatically checks fixed-size matrices at compile time, and
|
|
* throws at run-time if the sizes don't match:
|
|
*/
|
|
matrix_size N = detail::MatMulCheckedSize(left, right, size_tag());
|
|
|
|
/* Create an array with the right size (resize() is a no-op for
|
|
* fixed-size matrices):
|
|
*/
|
|
result_type C;
|
|
cml::et::detail::Resize(C, N);
|
|
|
|
/* XXX Specialize this for fixed-size matrices: */
|
|
typedef typename result_type::value_type value_type;
|
|
for(size_t i = 0; i < left.rows(); ++i) { /* rows */
|
|
for(size_t j = 0; j < right.cols(); ++j) { /* cols */
|
|
value_type sum(left(i,0)*right(0,j));
|
|
for(size_t k = 1; k < right.rows(); ++k) {
|
|
sum += (left(i,k)*right(k,j));
|
|
}
|
|
C(i,j) = sum;
|
|
}
|
|
}
|
|
|
|
return C;
|
|
}
|
|
|
|
} // namespace detail
|
|
|
|
|
|
/** operator*() for two matrices. */
|
|
template<typename E1, class AT1, typename L1,
|
|
typename E2, class AT2, typename L2,
|
|
typename BO>
|
|
inline typename et::MatrixPromote<
|
|
matrix<E1,AT1,BO,L1>, matrix<E2,AT2,BO,L2>
|
|
>::temporary_type
|
|
operator*(const matrix<E1,AT1,BO,L1>& left,
|
|
const matrix<E2,AT2,BO,L2>& right)
|
|
{
|
|
return detail::mul(left,right);
|
|
}
|
|
|
|
/** operator*() for a matrix and a MatrixXpr. */
|
|
template<typename E, class AT, typename BO, typename L, typename XprT>
|
|
inline typename et::MatrixPromote<
|
|
matrix<E,AT,BO,L>, typename XprT::result_type
|
|
>::temporary_type
|
|
operator*(const matrix<E,AT,BO,L>& left,
|
|
const et::MatrixXpr<XprT>& right)
|
|
{
|
|
/* Generate a temporary, and compute the right-hand expression: */
|
|
typedef typename et::MatrixXpr<XprT>::temporary_type expr_tmp;
|
|
expr_tmp tmp;
|
|
cml::et::detail::Resize(tmp,right.rows(),right.cols());
|
|
tmp = right;
|
|
|
|
return detail::mul(left,tmp);
|
|
}
|
|
|
|
/** operator*() for a MatrixXpr and a matrix. */
|
|
template<typename XprT, typename E, class AT, typename BO, typename L>
|
|
inline typename et::MatrixPromote<
|
|
typename XprT::result_type , matrix<E,AT,BO,L>
|
|
>::temporary_type
|
|
operator*(const et::MatrixXpr<XprT>& left,
|
|
const matrix<E,AT,BO,L>& right)
|
|
{
|
|
/* Generate a temporary, and compute the left-hand expression: */
|
|
typedef typename et::MatrixXpr<XprT>::temporary_type expr_tmp;
|
|
expr_tmp tmp;
|
|
cml::et::detail::Resize(tmp,left.rows(),left.cols());
|
|
tmp = left;
|
|
|
|
return detail::mul(tmp,right);
|
|
}
|
|
|
|
/** operator*() for two MatrixXpr's. */
|
|
template<typename XprT1, typename XprT2>
|
|
inline typename et::MatrixPromote<
|
|
typename XprT1::result_type, typename XprT2::result_type
|
|
>::temporary_type
|
|
operator*(const et::MatrixXpr<XprT1>& left,
|
|
const et::MatrixXpr<XprT2>& right)
|
|
{
|
|
/* Generate temporaries and compute expressions: */
|
|
typedef typename et::MatrixXpr<XprT1>::temporary_type left_tmp;
|
|
left_tmp ltmp;
|
|
cml::et::detail::Resize(ltmp,left.rows(),left.cols());
|
|
ltmp = left;
|
|
|
|
typedef typename et::MatrixXpr<XprT2>::temporary_type right_tmp;
|
|
right_tmp rtmp;
|
|
cml::et::detail::Resize(rtmp,right.rows(),right.cols());
|
|
rtmp = right;
|
|
|
|
return detail::mul(ltmp,rtmp);
|
|
}
|
|
|
|
} // namespace cml
|
|
|
|
#endif
|
|
|
|
// -------------------------------------------------------------------------
|
|
// vim:ft=cpp
|