286 lines
9.2 KiB
C++
286 lines
9.2 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 a matrix and a vector.
|
|
*
|
|
* @todo Implement smarter temporary generation.
|
|
*
|
|
* @todo Does it make sense to put mat-vec 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 matvec_mul_h
|
|
#define matvec_mul_h
|
|
|
|
#include <cml/core/cml_meta.h>
|
|
#include <cml/vector/vector_expr.h>
|
|
#include <cml/matrix/matrix_expr.h>
|
|
#include <cml/matvec/matvec_promotions.h>
|
|
|
|
/* This is used below to create a more meaningful compile-time error when
|
|
* mat-vec mul is not provided with the right arguments:
|
|
*/
|
|
struct mvmul_expects_one_matrix_and_one_vector_arg_error;
|
|
struct mvmul_expects_one_vector_and_one_matrix_arg_error;
|
|
|
|
namespace cml {
|
|
namespace detail {
|
|
|
|
/* For choosing the proper multiplication order: */
|
|
typedef true_type mul_Ax;
|
|
typedef false_type mul_xA;
|
|
|
|
/** Compute y = A*x. */
|
|
template<typename LeftT, typename RightT> inline
|
|
typename et::MatVecPromote<
|
|
typename et::ExprTraits<LeftT>::result_type,
|
|
typename et::ExprTraits<RightT>::result_type
|
|
>::temporary_type
|
|
mul(const LeftT& A, const RightT& x, mul_Ax)
|
|
{
|
|
/* Shorthand: */
|
|
typedef et::ExprTraits<LeftT> left_traits;
|
|
typedef et::ExprTraits<RightT> right_traits;
|
|
typedef typename left_traits::result_tag left_result;
|
|
typedef typename right_traits::result_tag right_result;
|
|
|
|
/* mul()[A*x] requires a matrix and a vector expression: */
|
|
CML_STATIC_REQUIRE_M(
|
|
(same_type<left_result, et::matrix_result_tag>::is_true
|
|
&& same_type<right_result, et::vector_result_tag>::is_true),
|
|
mvmul_expects_one_matrix_and_one_vector_arg_error);
|
|
/* Note: parens are required here so that the preprocessor ignores the
|
|
* commas.
|
|
*/
|
|
|
|
/* Get result type: */
|
|
typedef typename et::MatVecPromote<
|
|
typename left_traits::result_type,
|
|
typename right_traits::result_type
|
|
>::temporary_type result_type;
|
|
|
|
/* Record size type: */
|
|
typedef typename result_type::size_tag size_tag;
|
|
|
|
/* Check the size: */
|
|
size_t N = et::CheckedSize(A, x, size_tag());
|
|
|
|
/* Initialize the new vector: */
|
|
result_type y; cml::et::detail::Resize(y, N);
|
|
|
|
/* Compute y = A*x: */
|
|
typedef typename result_type::value_type sum_type;
|
|
for(size_t i = 0; i < N; ++i) {
|
|
/* XXX This should be unrolled. */
|
|
sum_type sum(A(i,0)*x[0]);
|
|
for(size_t k = 1; k < x.size(); ++k) {
|
|
sum += (A(i,k)*x[k]);
|
|
}
|
|
y[i] = sum;
|
|
}
|
|
|
|
return y;
|
|
}
|
|
|
|
/** Compute y = x*A. */
|
|
template<typename LeftT, typename RightT> inline
|
|
typename et::MatVecPromote<
|
|
typename et::ExprTraits<LeftT>::result_type,
|
|
typename et::ExprTraits<RightT>::result_type
|
|
>::temporary_type
|
|
mul(const LeftT& x, const RightT& A, mul_xA)
|
|
{
|
|
/* Shorthand: */
|
|
typedef et::ExprTraits<LeftT> left_traits;
|
|
typedef et::ExprTraits<RightT> right_traits;
|
|
typedef typename left_traits::result_tag left_result;
|
|
typedef typename right_traits::result_tag right_result;
|
|
|
|
/* mul()[x*A] requires a vector and a matrix expression: */
|
|
CML_STATIC_REQUIRE_M(
|
|
(same_type<left_result, et::vector_result_tag>::is_true
|
|
&& same_type<right_result, et::matrix_result_tag>::is_true),
|
|
mvmul_expects_one_vector_and_one_matrix_arg_error);
|
|
/* Note: parens are required here so that the preprocessor ignores the
|
|
* commas.
|
|
*/
|
|
|
|
/* Get result type: */
|
|
typedef typename et::MatVecPromote<
|
|
typename left_traits::result_type,
|
|
typename right_traits::result_type
|
|
>::temporary_type result_type;
|
|
|
|
/* Record size type: */
|
|
typedef typename result_type::size_tag size_tag;
|
|
|
|
/* Check the size: */
|
|
size_t N = et::CheckedSize(x, A, size_tag());
|
|
|
|
/* Initialize the new vector: */
|
|
result_type y; cml::et::detail::Resize(y, N);
|
|
|
|
/* Compute y = x*A: */
|
|
typedef typename result_type::value_type sum_type;
|
|
for(size_t i = 0; i < N; ++i) {
|
|
/* XXX This should be unrolled. */
|
|
sum_type sum(x[0]*A(0,i));
|
|
for(size_t k = 1; k < x.size(); ++k) {
|
|
sum += (x[k]*A(k,i));
|
|
}
|
|
y[i] = sum;
|
|
}
|
|
|
|
return y;
|
|
}
|
|
|
|
} // namespace detail
|
|
|
|
|
|
/** operator*() for a matrix and a vector. */
|
|
template<typename E1, class AT1, typename BO, class L,
|
|
typename E2, class AT2>
|
|
inline typename et::MatVecPromote<
|
|
matrix<E1,AT1,BO,L>, vector<E2,AT2>
|
|
>::temporary_type
|
|
operator*(const matrix<E1,AT1,BO,L>& left,
|
|
const vector<E2,AT2>& right)
|
|
{
|
|
return detail::mul(left,right,detail::mul_Ax());
|
|
}
|
|
|
|
/** operator*() for a matrix and a VectorXpr. */
|
|
template<typename E, class AT, class L, typename BO, typename XprT>
|
|
inline typename et::MatVecPromote<
|
|
matrix<E,AT,BO,L>, typename XprT::result_type
|
|
>::temporary_type
|
|
operator*(const matrix<E,AT,BO,L>& left,
|
|
const et::VectorXpr<XprT>& right)
|
|
{
|
|
/* Generate a temporary, and compute the right-hand expression: */
|
|
typename et::VectorXpr<XprT>::temporary_type right_tmp;
|
|
cml::et::detail::Resize(right_tmp,right.size());
|
|
right_tmp = right;
|
|
|
|
return detail::mul(left,right_tmp,detail::mul_Ax());
|
|
}
|
|
|
|
/** operator*() for a MatrixXpr and a vector. */
|
|
template<typename XprT, typename E, class AT>
|
|
inline typename et::MatVecPromote<
|
|
typename XprT::result_type, vector<E,AT>
|
|
>::temporary_type
|
|
operator*(const et::MatrixXpr<XprT>& left,
|
|
const vector<E,AT>& right)
|
|
{
|
|
/* Generate a temporary, and compute the left-hand expression: */
|
|
typename et::MatrixXpr<XprT>::temporary_type left_tmp;
|
|
cml::et::detail::Resize(left_tmp,left.rows(),left.cols());
|
|
left_tmp = left;
|
|
|
|
return detail::mul(left_tmp,right,detail::mul_Ax());
|
|
}
|
|
|
|
/** operator*() for a MatrixXpr and a VectorXpr. */
|
|
template<typename XprT1, typename XprT2>
|
|
inline typename et::MatVecPromote<
|
|
typename XprT1::result_type, typename XprT2::result_type
|
|
>::temporary_type
|
|
operator*(const et::MatrixXpr<XprT1>& left,
|
|
const et::VectorXpr<XprT2>& right)
|
|
{
|
|
/* Generate a temporary, and compute the left-hand expression: */
|
|
typename et::MatrixXpr<XprT1>::temporary_type left_tmp;
|
|
cml::et::detail::Resize(left_tmp,left.rows(),left.cols());
|
|
left_tmp = left;
|
|
|
|
/* Generate a temporary, and compute the right-hand expression: */
|
|
typename et::VectorXpr<XprT2>::temporary_type right_tmp;
|
|
cml::et::detail::Resize(right_tmp,right.size());
|
|
right_tmp = right;
|
|
|
|
return detail::mul(left_tmp,right_tmp,detail::mul_Ax());
|
|
}
|
|
|
|
/** operator*() for a vector and a matrix. */
|
|
template<typename E1, class AT1, typename E2, class AT2, typename BO, class L>
|
|
inline typename et::MatVecPromote<
|
|
vector<E1,AT1>, matrix<E2,AT2,BO,L>
|
|
>::temporary_type
|
|
operator*(const vector<E1,AT1>& left,
|
|
const matrix<E2,AT2,BO,L>& right)
|
|
{
|
|
return detail::mul(left,right,detail::mul_xA());
|
|
}
|
|
|
|
/** operator*() for a vector and a MatrixXpr. */
|
|
template<typename XprT, typename E, class AT>
|
|
inline typename et::MatVecPromote<
|
|
typename XprT::result_type, vector<E,AT>
|
|
>::temporary_type
|
|
operator*(const vector<E,AT>& left,
|
|
const et::MatrixXpr<XprT>& right)
|
|
{
|
|
/* Generate a temporary, and compute the right-hand expression: */
|
|
typename et::MatrixXpr<XprT>::temporary_type right_tmp;
|
|
cml::et::detail::Resize(right_tmp,right.rows(),right.cols());
|
|
right_tmp = right;
|
|
|
|
return detail::mul(left,right_tmp,detail::mul_xA());
|
|
}
|
|
|
|
/** operator*() for a VectorXpr and a matrix. */
|
|
template<typename XprT, typename E, class AT, typename BO, class L>
|
|
inline typename et::MatVecPromote<
|
|
typename XprT::result_type, matrix<E,AT,BO,L>
|
|
>::temporary_type
|
|
operator*(const et::VectorXpr<XprT>& left,
|
|
const matrix<E,AT,BO,L>& right)
|
|
{
|
|
/* Generate a temporary, and compute the left-hand expression: */
|
|
typename et::VectorXpr<XprT>::temporary_type left_tmp;
|
|
cml::et::detail::Resize(left_tmp,left.size());
|
|
left_tmp = left;
|
|
|
|
return detail::mul(left_tmp,right,detail::mul_xA());
|
|
}
|
|
|
|
/** operator*() for a VectorXpr and a MatrixXpr. */
|
|
template<typename XprT1, typename XprT2>
|
|
inline typename et::MatVecPromote<
|
|
typename XprT1::result_type, typename XprT2::result_type
|
|
>::temporary_type
|
|
operator*(const et::VectorXpr<XprT1>& left,
|
|
const et::MatrixXpr<XprT2>& right)
|
|
{
|
|
/* Generate a temporary, and compute the left-hand expression: */
|
|
typename et::VectorXpr<XprT1>::temporary_type left_tmp;
|
|
cml::et::detail::Resize(left_tmp,left.size());
|
|
left_tmp = left;
|
|
|
|
/* Generate a temporary, and compute the right-hand expression: */
|
|
typename et::MatrixXpr<XprT2>::temporary_type right_tmp;
|
|
cml::et::detail::Resize(right_tmp,right.rows(),right.cols());
|
|
right_tmp = right;
|
|
|
|
return detail::mul(left_tmp,right_tmp,detail::mul_xA());
|
|
}
|
|
|
|
} // namespace cml
|
|
|
|
#endif
|
|
|
|
// -------------------------------------------------------------------------
|
|
// vim:ft=cpp
|