eigen/Eigen/src/SparseCore/SparseProduct.h

98 lines
3.7 KiB
C++

// This file is part of Eigen, a lightweight C++ template library
// for linear algebra.
//
// Copyright (C) 2008-2014 Gael Guennebaud <gael.guennebaud@inria.fr>
//
// This Source Code Form is subject to the terms of the Mozilla
// Public License v. 2.0. If a copy of the MPL was not distributed
// with this file, You can obtain one at http://mozilla.org/MPL/2.0/.
#ifndef EIGEN_SPARSEPRODUCT_H
#define EIGEN_SPARSEPRODUCT_H
namespace Eigen {
/** \returns an expression of the product of two sparse matrices.
* By default a conservative product preserving the symbolic non zeros is performed.
* The automatic pruning of the small values can be achieved by calling the pruned() function
* in which case a totally different product algorithm is employed:
* \code
* C = (A*B).pruned(); // supress numerical zeros (exact)
* C = (A*B).pruned(ref);
* C = (A*B).pruned(ref,epsilon);
* \endcode
* where \c ref is a meaningful non zero reference value.
* */
template<typename Derived>
template<typename OtherDerived>
inline const Product<Derived,OtherDerived>
SparseMatrixBase<Derived>::operator*(const SparseMatrixBase<OtherDerived> &other) const
{
return Product<Derived,OtherDerived>(derived(), other.derived());
}
namespace internal {
// sparse * sparse
template<typename Lhs, typename Rhs, int ProductType>
struct generic_product_impl<Lhs, Rhs, SparseShape, SparseShape, ProductType>
{
template<typename Dest>
static void evalTo(Dest& dst, const Lhs& lhs, const Rhs& rhs)
{
typedef typename nested_eval<Lhs,Dynamic>::type LhsNested;
typedef typename nested_eval<Rhs,Dynamic>::type RhsNested;
LhsNested lhsNested(lhs);
RhsNested rhsNested(rhs);
internal::conservative_sparse_sparse_product_selector<typename remove_all<LhsNested>::type,
typename remove_all<RhsNested>::type, Dest>::run(lhsNested,rhsNested,dst);
}
};
// sparse * sparse-triangular
template<typename Lhs, typename Rhs, int ProductType>
struct generic_product_impl<Lhs, Rhs, SparseShape, SparseTriangularShape, ProductType>
: public generic_product_impl<Lhs, Rhs, SparseShape, SparseShape, ProductType>
{};
// sparse-triangular * sparse
template<typename Lhs, typename Rhs, int ProductType>
struct generic_product_impl<Lhs, Rhs, SparseTriangularShape, SparseShape, ProductType>
: public generic_product_impl<Lhs, Rhs, SparseShape, SparseShape, ProductType>
{};
template<typename Lhs, typename Rhs, int Options>
struct evaluator<SparseView<Product<Lhs, Rhs, Options> > >
: public evaluator<typename Product<Lhs, Rhs, DefaultProduct>::PlainObject>
{
typedef SparseView<Product<Lhs, Rhs, Options> > XprType;
typedef typename XprType::PlainObject PlainObject;
typedef evaluator<PlainObject> Base;
typedef evaluator nestedType;
explicit evaluator(const XprType& xpr)
: m_result(xpr.rows(), xpr.cols())
{
using std::abs;
::new (static_cast<Base*>(this)) Base(m_result);
typedef typename nested_eval<Lhs,Dynamic>::type LhsNested;
typedef typename nested_eval<Rhs,Dynamic>::type RhsNested;
LhsNested lhsNested(xpr.nestedExpression().lhs());
RhsNested rhsNested(xpr.nestedExpression().rhs());
internal::sparse_sparse_product_with_pruning_selector<typename remove_all<LhsNested>::type,
typename remove_all<RhsNested>::type, PlainObject>::run(lhsNested,rhsNested,m_result,
abs(xpr.reference())*xpr.epsilon());
}
protected:
PlainObject m_result;
};
} // end namespace internal
} // end namespace Eigen
#endif // EIGEN_SPARSEPRODUCT_H