diff options
author | Gael Guennebaud <g.gael@free.fr> | 2014-02-19 11:33:29 +0100 |
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committer | Gael Guennebaud <g.gael@free.fr> | 2014-02-19 11:33:29 +0100 |
commit | ccc41128fb936563651a3c5b25bfc80f303710bf (patch) | |
tree | 95f9c13ef7bfa277c30364bb898b64e27f0f510b /Eigen/src/Core/Solve.h | |
parent | b3a07eecc5ad19f418f15d70d1517f8b7e07dc1b (diff) |
Add a Solve expression for uniform treatment of solve() methods.
Diffstat (limited to 'Eigen/src/Core/Solve.h')
-rw-r--r-- | Eigen/src/Core/Solve.h | 145 |
1 files changed, 145 insertions, 0 deletions
diff --git a/Eigen/src/Core/Solve.h b/Eigen/src/Core/Solve.h new file mode 100644 index 000000000..2da2aff56 --- /dev/null +++ b/Eigen/src/Core/Solve.h @@ -0,0 +1,145 @@ +// This file is part of Eigen, a lightweight C++ template library +// for linear algebra. +// +// Copyright (C) 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_INVERSE_H +#define EIGEN_INVERSE_H + +namespace Eigen { + +template<typename Decomposition, typename RhsType, typename StorageKind> class SolveImpl; + +/** \class Solve + * \ingroup Core_Module + * + * \brief Pseudo expression representing a solving operation + * + * \tparam Decomposition the type of the matrix or decomposion object + * \tparam Rhstype the type of the right-hand side + * + * This class represents an expression of A.solve(B) + * and most of the time this is the only way it is used. + * + */ +namespace internal { + +// this solve_traits class permits to determine the evaluation type with respect to storage kind (Dense vs Sparse) +template<typename Decomposition, typename RhsType,typename StorageKind> struct solve_traits; + +template<typename Decomposition, typename RhsType> +struct solve_traits<Decomposition,RhsType,Dense> +{ + typedef typename Decomposition::MatrixType MatrixType; + typedef Matrix<typename RhsType::Scalar, + MatrixType::ColsAtCompileTime, + RhsType::ColsAtCompileTime, + RhsType::PlainObject::Options, + MatrixType::MaxColsAtCompileTime, + RhsType::MaxColsAtCompileTime> PlainObject; +}; + +template<typename Decomposition, typename RhsType> +struct traits<Solve<Decomposition, RhsType> > + : traits<typename solve_traits<Decomposition,RhsType,typename internal::traits<RhsType>::StorageKind>::PlainObject> +{ + typedef typename solve_traits<Decomposition,RhsType,typename internal::traits<RhsType>::StorageKind>::PlainObject PlainObject; + typedef traits<PlainObject> BaseTraits; + enum { + Flags = BaseTraits::Flags & RowMajorBit, + CoeffReadCost = Dynamic + }; +}; + +} + + +template<typename Decomposition, typename RhsType> +class Solve : public SolveImpl<Decomposition,RhsType,typename internal::traits<RhsType>::StorageKind> +{ +public: + typedef typename RhsType::Index Index; + typedef typename internal::traits<Solve>::PlainObject PlainObject; + + Solve(const Decomposition &dec, const RhsType &rhs) + : m_dec(dec), m_rhs(rhs) + {} + + EIGEN_DEVICE_FUNC Index rows() const { return m_dec.rows(); } + EIGEN_DEVICE_FUNC Index cols() const { return m_rhs.cols(); } + + EIGEN_DEVICE_FUNC const Decomposition& dec() const { return m_dec; } + EIGEN_DEVICE_FUNC const RhsType& rhs() const { return m_rhs; } + +protected: + const Decomposition &m_dec; + const RhsType &m_rhs; +}; + + +// Specilaization of the Solve expression for dense results +template<typename Decomposition, typename RhsType> +class SolveImpl<Decomposition,RhsType,Dense> + : public MatrixBase<Solve<Decomposition,RhsType> > +{ + typedef Solve<Decomposition,RhsType> Derived; + +public: + + typedef MatrixBase<Solve<Decomposition,RhsType> > Base; + EIGEN_DENSE_PUBLIC_INTERFACE(Derived) + +private: + + Scalar coeff(Index row, Index col) const; + Scalar coeff(Index i) const; +}; + + +namespace internal { + +// Evaluator of Solve -> eval into a temporary +template<typename Decomposition, typename RhsType> +struct evaluator<Solve<Decomposition,RhsType> > + : public evaluator<typename Solve<Decomposition,RhsType>::PlainObject>::type +{ + typedef Solve<Decomposition,RhsType> SolveType; + typedef typename SolveType::PlainObject PlainObject; + typedef typename evaluator<PlainObject>::type Base; + + typedef evaluator type; + typedef evaluator nestedType; + + evaluator(const SolveType& solve) + : m_result(solve.rows(), solve.cols()) + { + ::new (static_cast<Base*>(this)) Base(m_result); + solve.dec()._solve_impl(solve.rhs(), m_result); + } + +protected: + PlainObject m_result; +}; + +// Specialization for "dst = dec.solve(rhs)" +// NOTE we need to specialize it for Dense2Dense to avoid ambiguous specialization error and a Sparse2Sparse specialization must exist somewhere +template<typename DstXprType, typename DecType, typename RhsType, typename Scalar> +struct Assignment<DstXprType, Solve<DecType,RhsType>, internal::assign_op<Scalar>, Dense2Dense, Scalar> +{ + typedef Solve<DecType,RhsType> SrcXprType; + static void run(DstXprType &dst, const SrcXprType &src, const internal::assign_op<Scalar> &) + { + // FIXME shall we resize dst here? + src.dec()._solve_impl(src.rhs(), dst); + } +}; + +} // end namepsace internal + +} // end namespace Eigen + +#endif // EIGEN_SOLVE_H |