| // This file is part of Eigen, a lightweight C++ template library |
| // for linear algebra. |
| // |
| // Copyright (C) 2010-2011 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_TRANSPOSITIONS_H |
| #define EIGEN_TRANSPOSITIONS_H |
| |
| // IWYU pragma: private |
| #include "./InternalHeaderCheck.h" |
| |
| namespace Eigen { |
| |
| template <typename Derived> |
| class TranspositionsBase { |
| typedef internal::traits<Derived> Traits; |
| |
| public: |
| typedef typename Traits::IndicesType IndicesType; |
| typedef typename IndicesType::Scalar StorageIndex; |
| typedef Eigen::Index Index; ///< \deprecated since Eigen 3.3 |
| |
| EIGEN_DEVICE_FUNC Derived& derived() { return *static_cast<Derived*>(this); } |
| EIGEN_DEVICE_FUNC const Derived& derived() const { return *static_cast<const Derived*>(this); } |
| |
| /** Copies the \a other transpositions into \c *this */ |
| template <typename OtherDerived> |
| Derived& operator=(const TranspositionsBase<OtherDerived>& other) { |
| indices() = other.indices(); |
| return derived(); |
| } |
| |
| /** \returns the number of transpositions */ |
| EIGEN_DEVICE_FUNC Index size() const { return indices().size(); } |
| /** \returns the number of rows of the equivalent permutation matrix */ |
| EIGEN_DEVICE_FUNC Index rows() const { return indices().size(); } |
| /** \returns the number of columns of the equivalent permutation matrix */ |
| EIGEN_DEVICE_FUNC Index cols() const { return indices().size(); } |
| |
| /** Direct access to the underlying index vector */ |
| EIGEN_DEVICE_FUNC inline const StorageIndex& coeff(Index i) const { return indices().coeff(i); } |
| /** Direct access to the underlying index vector */ |
| inline StorageIndex& coeffRef(Index i) { return indices().coeffRef(i); } |
| /** Direct access to the underlying index vector */ |
| inline const StorageIndex& operator()(Index i) const { return indices()(i); } |
| /** Direct access to the underlying index vector */ |
| inline StorageIndex& operator()(Index i) { return indices()(i); } |
| /** Direct access to the underlying index vector */ |
| inline const StorageIndex& operator[](Index i) const { return indices()(i); } |
| /** Direct access to the underlying index vector */ |
| inline StorageIndex& operator[](Index i) { return indices()(i); } |
| |
| /** const version of indices(). */ |
| EIGEN_DEVICE_FUNC const IndicesType& indices() const { return derived().indices(); } |
| /** \returns a reference to the stored array representing the transpositions. */ |
| EIGEN_DEVICE_FUNC IndicesType& indices() { return derived().indices(); } |
| |
| /** Resizes to given size. */ |
| inline void resize(Index newSize) { indices().resize(newSize); } |
| |
| /** Sets \c *this to represents an identity transformation */ |
| void setIdentity() { |
| for (StorageIndex i = 0; i < indices().size(); ++i) coeffRef(i) = i; |
| } |
| |
| // FIXME: do we want such methods ? |
| // might be useful when the target matrix expression is complex, e.g.: |
| // object.matrix().block(..,..,..,..) = trans * object.matrix().block(..,..,..,..); |
| /* |
| template<typename MatrixType> |
| void applyForwardToRows(MatrixType& mat) const |
| { |
| for(Index k=0 ; k<size() ; ++k) |
| if(m_indices(k)!=k) |
| mat.row(k).swap(mat.row(m_indices(k))); |
| } |
| |
| template<typename MatrixType> |
| void applyBackwardToRows(MatrixType& mat) const |
| { |
| for(Index k=size()-1 ; k>=0 ; --k) |
| if(m_indices(k)!=k) |
| mat.row(k).swap(mat.row(m_indices(k))); |
| } |
| */ |
| |
| /** \returns the inverse transformation */ |
| inline Transpose<TranspositionsBase> inverse() const { return Transpose<TranspositionsBase>(derived()); } |
| |
| /** \returns the tranpose transformation */ |
| inline Transpose<TranspositionsBase> transpose() const { return Transpose<TranspositionsBase>(derived()); } |
| |
| protected: |
| }; |
| |
| namespace internal { |
| template <int SizeAtCompileTime, int MaxSizeAtCompileTime, typename StorageIndex_> |
| struct traits<Transpositions<SizeAtCompileTime, MaxSizeAtCompileTime, StorageIndex_> > |
| : traits<PermutationMatrix<SizeAtCompileTime, MaxSizeAtCompileTime, StorageIndex_> > { |
| typedef Matrix<StorageIndex_, SizeAtCompileTime, 1, 0, MaxSizeAtCompileTime, 1> IndicesType; |
| typedef TranspositionsStorage StorageKind; |
| }; |
| } // namespace internal |
| |
| /** \class Transpositions |
| * \ingroup Core_Module |
| * |
| * \brief Represents a sequence of transpositions (row/column interchange) |
| * |
| * \tparam SizeAtCompileTime the number of transpositions, or Dynamic |
| * \tparam MaxSizeAtCompileTime the maximum number of transpositions, or Dynamic. This optional parameter defaults to |
| * SizeAtCompileTime. Most of the time, you should not have to specify it. |
| * |
| * This class represents a permutation transformation as a sequence of \em n transpositions |
| * \f$[T_{n-1} \ldots T_{i} \ldots T_{0}]\f$. It is internally stored as a vector of integers \c indices. |
| * Each transposition \f$ T_{i} \f$ applied on the left of a matrix (\f$ T_{i} M\f$) interchanges |
| * the rows \c i and \c indices[i] of the matrix \c M. |
| * A transposition applied on the right (e.g., \f$ M T_{i}\f$) yields a column interchange. |
| * |
| * Compared to the class PermutationMatrix, such a sequence of transpositions is what is |
| * computed during a decomposition with pivoting, and it is faster when applying the permutation in-place. |
| * |
| * To apply a sequence of transpositions to a matrix, simply use the operator * as in the following example: |
| * \code |
| * Transpositions tr; |
| * MatrixXf mat; |
| * mat = tr * mat; |
| * \endcode |
| * In this example, we detect that the matrix appears on both side, and so the transpositions |
| * are applied in-place without any temporary or extra copy. |
| * |
| * \sa class PermutationMatrix |
| */ |
| |
| template <int SizeAtCompileTime, int MaxSizeAtCompileTime, typename StorageIndex_> |
| class Transpositions |
| : public TranspositionsBase<Transpositions<SizeAtCompileTime, MaxSizeAtCompileTime, StorageIndex_> > { |
| typedef internal::traits<Transpositions> Traits; |
| |
| public: |
| typedef TranspositionsBase<Transpositions> Base; |
| typedef typename Traits::IndicesType IndicesType; |
| typedef typename IndicesType::Scalar StorageIndex; |
| |
| inline Transpositions() {} |
| |
| /** Copy constructor. */ |
| template <typename OtherDerived> |
| inline Transpositions(const TranspositionsBase<OtherDerived>& other) : m_indices(other.indices()) {} |
| |
| /** Generic constructor from expression of the transposition indices. */ |
| template <typename Other> |
| explicit inline Transpositions(const MatrixBase<Other>& indices) : m_indices(indices) {} |
| |
| /** Copies the \a other transpositions into \c *this */ |
| template <typename OtherDerived> |
| Transpositions& operator=(const TranspositionsBase<OtherDerived>& other) { |
| return Base::operator=(other); |
| } |
| |
| /** Constructs an uninitialized permutation matrix of given size. |
| */ |
| inline Transpositions(Index size) : m_indices(size) {} |
| |
| /** const version of indices(). */ |
| EIGEN_DEVICE_FUNC const IndicesType& indices() const { return m_indices; } |
| /** \returns a reference to the stored array representing the transpositions. */ |
| EIGEN_DEVICE_FUNC IndicesType& indices() { return m_indices; } |
| |
| protected: |
| IndicesType m_indices; |
| }; |
| |
| namespace internal { |
| template <int SizeAtCompileTime, int MaxSizeAtCompileTime, typename StorageIndex_, int PacketAccess_> |
| struct traits<Map<Transpositions<SizeAtCompileTime, MaxSizeAtCompileTime, StorageIndex_>, PacketAccess_> > |
| : traits<PermutationMatrix<SizeAtCompileTime, MaxSizeAtCompileTime, StorageIndex_> > { |
| typedef Map<const Matrix<StorageIndex_, SizeAtCompileTime, 1, 0, MaxSizeAtCompileTime, 1>, PacketAccess_> IndicesType; |
| typedef StorageIndex_ StorageIndex; |
| typedef TranspositionsStorage StorageKind; |
| }; |
| } // namespace internal |
| |
| template <int SizeAtCompileTime, int MaxSizeAtCompileTime, typename StorageIndex_, int PacketAccess> |
| class Map<Transpositions<SizeAtCompileTime, MaxSizeAtCompileTime, StorageIndex_>, PacketAccess> |
| : public TranspositionsBase< |
| Map<Transpositions<SizeAtCompileTime, MaxSizeAtCompileTime, StorageIndex_>, PacketAccess> > { |
| typedef internal::traits<Map> Traits; |
| |
| public: |
| typedef TranspositionsBase<Map> Base; |
| typedef typename Traits::IndicesType IndicesType; |
| typedef typename IndicesType::Scalar StorageIndex; |
| |
| explicit inline Map(const StorageIndex* indicesPtr) : m_indices(indicesPtr) {} |
| |
| inline Map(const StorageIndex* indicesPtr, Index size) : m_indices(indicesPtr, size) {} |
| |
| /** Copies the \a other transpositions into \c *this */ |
| template <typename OtherDerived> |
| Map& operator=(const TranspositionsBase<OtherDerived>& other) { |
| return Base::operator=(other); |
| } |
| |
| #ifndef EIGEN_PARSED_BY_DOXYGEN |
| /** This is a special case of the templated operator=. Its purpose is to |
| * prevent a default operator= from hiding the templated operator=. |
| */ |
| Map& operator=(const Map& other) { |
| m_indices = other.m_indices; |
| return *this; |
| } |
| #endif |
| |
| /** const version of indices(). */ |
| EIGEN_DEVICE_FUNC const IndicesType& indices() const { return m_indices; } |
| |
| /** \returns a reference to the stored array representing the transpositions. */ |
| EIGEN_DEVICE_FUNC IndicesType& indices() { return m_indices; } |
| |
| protected: |
| IndicesType m_indices; |
| }; |
| |
| namespace internal { |
| template <typename IndicesType_> |
| struct traits<TranspositionsWrapper<IndicesType_> > : traits<PermutationWrapper<IndicesType_> > { |
| typedef TranspositionsStorage StorageKind; |
| }; |
| } // namespace internal |
| |
| template <typename IndicesType_> |
| class TranspositionsWrapper : public TranspositionsBase<TranspositionsWrapper<IndicesType_> > { |
| typedef internal::traits<TranspositionsWrapper> Traits; |
| |
| public: |
| typedef TranspositionsBase<TranspositionsWrapper> Base; |
| typedef typename Traits::IndicesType IndicesType; |
| typedef typename IndicesType::Scalar StorageIndex; |
| |
| explicit inline TranspositionsWrapper(IndicesType& indices) : m_indices(indices) {} |
| |
| /** Copies the \a other transpositions into \c *this */ |
| template <typename OtherDerived> |
| TranspositionsWrapper& operator=(const TranspositionsBase<OtherDerived>& other) { |
| return Base::operator=(other); |
| } |
| |
| /** const version of indices(). */ |
| EIGEN_DEVICE_FUNC const IndicesType& indices() const { return m_indices; } |
| |
| /** \returns a reference to the stored array representing the transpositions. */ |
| EIGEN_DEVICE_FUNC IndicesType& indices() { return m_indices; } |
| |
| protected: |
| typename IndicesType::Nested m_indices; |
| }; |
| |
| /** \returns the \a matrix with the \a transpositions applied to the columns. |
| */ |
| template <typename MatrixDerived, typename TranspositionsDerived> |
| EIGEN_DEVICE_FUNC const Product<MatrixDerived, TranspositionsDerived, AliasFreeProduct> operator*( |
| const MatrixBase<MatrixDerived>& matrix, const TranspositionsBase<TranspositionsDerived>& transpositions) { |
| return Product<MatrixDerived, TranspositionsDerived, AliasFreeProduct>(matrix.derived(), transpositions.derived()); |
| } |
| |
| /** \returns the \a matrix with the \a transpositions applied to the rows. |
| */ |
| template <typename TranspositionsDerived, typename MatrixDerived> |
| EIGEN_DEVICE_FUNC const Product<TranspositionsDerived, MatrixDerived, AliasFreeProduct> operator*( |
| const TranspositionsBase<TranspositionsDerived>& transpositions, const MatrixBase<MatrixDerived>& matrix) { |
| return Product<TranspositionsDerived, MatrixDerived, AliasFreeProduct>(transpositions.derived(), matrix.derived()); |
| } |
| |
| // Template partial specialization for transposed/inverse transpositions |
| |
| namespace internal { |
| |
| template <typename Derived> |
| struct traits<Transpose<TranspositionsBase<Derived> > > : traits<Derived> {}; |
| |
| } // end namespace internal |
| |
| template <typename TranspositionsDerived> |
| class Transpose<TranspositionsBase<TranspositionsDerived> > { |
| typedef TranspositionsDerived TranspositionType; |
| typedef typename TranspositionType::IndicesType IndicesType; |
| |
| public: |
| explicit Transpose(const TranspositionType& t) : m_transpositions(t) {} |
| |
| EIGEN_DEVICE_FUNC EIGEN_CONSTEXPR Index size() const EIGEN_NOEXCEPT { return m_transpositions.size(); } |
| EIGEN_DEVICE_FUNC EIGEN_CONSTEXPR Index rows() const EIGEN_NOEXCEPT { return m_transpositions.size(); } |
| EIGEN_DEVICE_FUNC EIGEN_CONSTEXPR Index cols() const EIGEN_NOEXCEPT { return m_transpositions.size(); } |
| |
| /** \returns the \a matrix with the inverse transpositions applied to the columns. |
| */ |
| template <typename OtherDerived> |
| friend const Product<OtherDerived, Transpose, AliasFreeProduct> operator*(const MatrixBase<OtherDerived>& matrix, |
| const Transpose& trt) { |
| return Product<OtherDerived, Transpose, AliasFreeProduct>(matrix.derived(), trt); |
| } |
| |
| /** \returns the \a matrix with the inverse transpositions applied to the rows. |
| */ |
| template <typename OtherDerived> |
| const Product<Transpose, OtherDerived, AliasFreeProduct> operator*(const MatrixBase<OtherDerived>& matrix) const { |
| return Product<Transpose, OtherDerived, AliasFreeProduct>(*this, matrix.derived()); |
| } |
| |
| EIGEN_DEVICE_FUNC const TranspositionType& nestedExpression() const { return m_transpositions; } |
| |
| protected: |
| const TranspositionType& m_transpositions; |
| }; |
| |
| } // end namespace Eigen |
| |
| #endif // EIGEN_TRANSPOSITIONS_H |