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diff --git a/runtimes/nn/depend/external/eigen/Eigen/src/Eigenvalues/ComplexEigenSolver.h b/runtimes/nn/depend/external/eigen/Eigen/src/Eigenvalues/ComplexEigenSolver.h new file mode 100644 index 000000000..dc5fae06a --- /dev/null +++ b/runtimes/nn/depend/external/eigen/Eigen/src/Eigenvalues/ComplexEigenSolver.h @@ -0,0 +1,346 @@ +// This file is part of Eigen, a lightweight C++ template library +// for linear algebra. +// +// Copyright (C) 2009 Claire Maurice +// Copyright (C) 2009 Gael Guennebaud <gael.guennebaud@inria.fr> +// Copyright (C) 2010,2012 Jitse Niesen <jitse@maths.leeds.ac.uk> +// +// 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_COMPLEX_EIGEN_SOLVER_H +#define EIGEN_COMPLEX_EIGEN_SOLVER_H + +#include "./ComplexSchur.h" + +namespace Eigen { + +/** \eigenvalues_module \ingroup Eigenvalues_Module + * + * + * \class ComplexEigenSolver + * + * \brief Computes eigenvalues and eigenvectors of general complex matrices + * + * \tparam _MatrixType the type of the matrix of which we are + * computing the eigendecomposition; this is expected to be an + * instantiation of the Matrix class template. + * + * The eigenvalues and eigenvectors of a matrix \f$ A \f$ are scalars + * \f$ \lambda \f$ and vectors \f$ v \f$ such that \f$ Av = \lambda v + * \f$. If \f$ D \f$ is a diagonal matrix with the eigenvalues on + * the diagonal, and \f$ V \f$ is a matrix with the eigenvectors as + * its columns, then \f$ A V = V D \f$. The matrix \f$ V \f$ is + * almost always invertible, in which case we have \f$ A = V D V^{-1} + * \f$. This is called the eigendecomposition. + * + * The main function in this class is compute(), which computes the + * eigenvalues and eigenvectors of a given function. The + * documentation for that function contains an example showing the + * main features of the class. + * + * \sa class EigenSolver, class SelfAdjointEigenSolver + */ +template<typename _MatrixType> class ComplexEigenSolver +{ + public: + + /** \brief Synonym for the template parameter \p _MatrixType. */ + typedef _MatrixType MatrixType; + + enum { + RowsAtCompileTime = MatrixType::RowsAtCompileTime, + ColsAtCompileTime = MatrixType::ColsAtCompileTime, + Options = MatrixType::Options, + MaxRowsAtCompileTime = MatrixType::MaxRowsAtCompileTime, + MaxColsAtCompileTime = MatrixType::MaxColsAtCompileTime + }; + + /** \brief Scalar type for matrices of type #MatrixType. */ + typedef typename MatrixType::Scalar Scalar; + typedef typename NumTraits<Scalar>::Real RealScalar; + typedef Eigen::Index Index; ///< \deprecated since Eigen 3.3 + + /** \brief Complex scalar type for #MatrixType. + * + * This is \c std::complex<Scalar> if #Scalar is real (e.g., + * \c float or \c double) and just \c Scalar if #Scalar is + * complex. + */ + typedef std::complex<RealScalar> ComplexScalar; + + /** \brief Type for vector of eigenvalues as returned by eigenvalues(). + * + * This is a column vector with entries of type #ComplexScalar. + * The length of the vector is the size of #MatrixType. + */ + typedef Matrix<ComplexScalar, ColsAtCompileTime, 1, Options&(~RowMajor), MaxColsAtCompileTime, 1> EigenvalueType; + + /** \brief Type for matrix of eigenvectors as returned by eigenvectors(). + * + * This is a square matrix with entries of type #ComplexScalar. + * The size is the same as the size of #MatrixType. + */ + typedef Matrix<ComplexScalar, RowsAtCompileTime, ColsAtCompileTime, Options, MaxRowsAtCompileTime, MaxColsAtCompileTime> EigenvectorType; + + /** \brief Default constructor. + * + * The default constructor is useful in cases in which the user intends to + * perform decompositions via compute(). + */ + ComplexEigenSolver() + : m_eivec(), + m_eivalues(), + m_schur(), + m_isInitialized(false), + m_eigenvectorsOk(false), + m_matX() + {} + + /** \brief Default Constructor with memory preallocation + * + * Like the default constructor but with preallocation of the internal data + * according to the specified problem \a size. + * \sa ComplexEigenSolver() + */ + explicit ComplexEigenSolver(Index size) + : m_eivec(size, size), + m_eivalues(size), + m_schur(size), + m_isInitialized(false), + m_eigenvectorsOk(false), + m_matX(size, size) + {} + + /** \brief Constructor; computes eigendecomposition of given matrix. + * + * \param[in] matrix Square matrix whose eigendecomposition is to be computed. + * \param[in] computeEigenvectors If true, both the eigenvectors and the + * eigenvalues are computed; if false, only the eigenvalues are + * computed. + * + * This constructor calls compute() to compute the eigendecomposition. + */ + template<typename InputType> + explicit ComplexEigenSolver(const EigenBase<InputType>& matrix, bool computeEigenvectors = true) + : m_eivec(matrix.rows(),matrix.cols()), + m_eivalues(matrix.cols()), + m_schur(matrix.rows()), + m_isInitialized(false), + m_eigenvectorsOk(false), + m_matX(matrix.rows(),matrix.cols()) + { + compute(matrix.derived(), computeEigenvectors); + } + + /** \brief Returns the eigenvectors of given matrix. + * + * \returns A const reference to the matrix whose columns are the eigenvectors. + * + * \pre Either the constructor + * ComplexEigenSolver(const MatrixType& matrix, bool) or the member + * function compute(const MatrixType& matrix, bool) has been called before + * to compute the eigendecomposition of a matrix, and + * \p computeEigenvectors was set to true (the default). + * + * This function returns a matrix whose columns are the eigenvectors. Column + * \f$ k \f$ is an eigenvector corresponding to eigenvalue number \f$ k + * \f$ as returned by eigenvalues(). The eigenvectors are normalized to + * have (Euclidean) norm equal to one. The matrix returned by this + * function is the matrix \f$ V \f$ in the eigendecomposition \f$ A = V D + * V^{-1} \f$, if it exists. + * + * Example: \include ComplexEigenSolver_eigenvectors.cpp + * Output: \verbinclude ComplexEigenSolver_eigenvectors.out + */ + const EigenvectorType& eigenvectors() const + { + eigen_assert(m_isInitialized && "ComplexEigenSolver is not initialized."); + eigen_assert(m_eigenvectorsOk && "The eigenvectors have not been computed together with the eigenvalues."); + return m_eivec; + } + + /** \brief Returns the eigenvalues of given matrix. + * + * \returns A const reference to the column vector containing the eigenvalues. + * + * \pre Either the constructor + * ComplexEigenSolver(const MatrixType& matrix, bool) or the member + * function compute(const MatrixType& matrix, bool) has been called before + * to compute the eigendecomposition of a matrix. + * + * This function returns a column vector containing the + * eigenvalues. Eigenvalues are repeated according to their + * algebraic multiplicity, so there are as many eigenvalues as + * rows in the matrix. The eigenvalues are not sorted in any particular + * order. + * + * Example: \include ComplexEigenSolver_eigenvalues.cpp + * Output: \verbinclude ComplexEigenSolver_eigenvalues.out + */ + const EigenvalueType& eigenvalues() const + { + eigen_assert(m_isInitialized && "ComplexEigenSolver is not initialized."); + return m_eivalues; + } + + /** \brief Computes eigendecomposition of given matrix. + * + * \param[in] matrix Square matrix whose eigendecomposition is to be computed. + * \param[in] computeEigenvectors If true, both the eigenvectors and the + * eigenvalues are computed; if false, only the eigenvalues are + * computed. + * \returns Reference to \c *this + * + * This function computes the eigenvalues of the complex matrix \p matrix. + * The eigenvalues() function can be used to retrieve them. If + * \p computeEigenvectors is true, then the eigenvectors are also computed + * and can be retrieved by calling eigenvectors(). + * + * The matrix is first reduced to Schur form using the + * ComplexSchur class. The Schur decomposition is then used to + * compute the eigenvalues and eigenvectors. + * + * The cost of the computation is dominated by the cost of the + * Schur decomposition, which is \f$ O(n^3) \f$ where \f$ n \f$ + * is the size of the matrix. + * + * Example: \include ComplexEigenSolver_compute.cpp + * Output: \verbinclude ComplexEigenSolver_compute.out + */ + template<typename InputType> + ComplexEigenSolver& compute(const EigenBase<InputType>& matrix, bool computeEigenvectors = true); + + /** \brief Reports whether previous computation was successful. + * + * \returns \c Success if computation was succesful, \c NoConvergence otherwise. + */ + ComputationInfo info() const + { + eigen_assert(m_isInitialized && "ComplexEigenSolver is not initialized."); + return m_schur.info(); + } + + /** \brief Sets the maximum number of iterations allowed. */ + ComplexEigenSolver& setMaxIterations(Index maxIters) + { + m_schur.setMaxIterations(maxIters); + return *this; + } + + /** \brief Returns the maximum number of iterations. */ + Index getMaxIterations() + { + return m_schur.getMaxIterations(); + } + + protected: + + static void check_template_parameters() + { + EIGEN_STATIC_ASSERT_NON_INTEGER(Scalar); + } + + EigenvectorType m_eivec; + EigenvalueType m_eivalues; + ComplexSchur<MatrixType> m_schur; + bool m_isInitialized; + bool m_eigenvectorsOk; + EigenvectorType m_matX; + + private: + void doComputeEigenvectors(RealScalar matrixnorm); + void sortEigenvalues(bool computeEigenvectors); +}; + + +template<typename MatrixType> +template<typename InputType> +ComplexEigenSolver<MatrixType>& +ComplexEigenSolver<MatrixType>::compute(const EigenBase<InputType>& matrix, bool computeEigenvectors) +{ + check_template_parameters(); + + // this code is inspired from Jampack + eigen_assert(matrix.cols() == matrix.rows()); + + // Do a complex Schur decomposition, A = U T U^* + // The eigenvalues are on the diagonal of T. + m_schur.compute(matrix.derived(), computeEigenvectors); + + if(m_schur.info() == Success) + { + m_eivalues = m_schur.matrixT().diagonal(); + if(computeEigenvectors) + doComputeEigenvectors(m_schur.matrixT().norm()); + sortEigenvalues(computeEigenvectors); + } + + m_isInitialized = true; + m_eigenvectorsOk = computeEigenvectors; + return *this; +} + + +template<typename MatrixType> +void ComplexEigenSolver<MatrixType>::doComputeEigenvectors(RealScalar matrixnorm) +{ + const Index n = m_eivalues.size(); + + matrixnorm = numext::maxi(matrixnorm,(std::numeric_limits<RealScalar>::min)()); + + // Compute X such that T = X D X^(-1), where D is the diagonal of T. + // The matrix X is unit triangular. + m_matX = EigenvectorType::Zero(n, n); + for(Index k=n-1 ; k>=0 ; k--) + { + m_matX.coeffRef(k,k) = ComplexScalar(1.0,0.0); + // Compute X(i,k) using the (i,k) entry of the equation X T = D X + for(Index i=k-1 ; i>=0 ; i--) + { + m_matX.coeffRef(i,k) = -m_schur.matrixT().coeff(i,k); + if(k-i-1>0) + m_matX.coeffRef(i,k) -= (m_schur.matrixT().row(i).segment(i+1,k-i-1) * m_matX.col(k).segment(i+1,k-i-1)).value(); + ComplexScalar z = m_schur.matrixT().coeff(i,i) - m_schur.matrixT().coeff(k,k); + if(z==ComplexScalar(0)) + { + // If the i-th and k-th eigenvalue are equal, then z equals 0. + // Use a small value instead, to prevent division by zero. + numext::real_ref(z) = NumTraits<RealScalar>::epsilon() * matrixnorm; + } + m_matX.coeffRef(i,k) = m_matX.coeff(i,k) / z; + } + } + + // Compute V as V = U X; now A = U T U^* = U X D X^(-1) U^* = V D V^(-1) + m_eivec.noalias() = m_schur.matrixU() * m_matX; + // .. and normalize the eigenvectors + for(Index k=0 ; k<n ; k++) + { + m_eivec.col(k).normalize(); + } +} + + +template<typename MatrixType> +void ComplexEigenSolver<MatrixType>::sortEigenvalues(bool computeEigenvectors) +{ + const Index n = m_eivalues.size(); + for (Index i=0; i<n; i++) + { + Index k; + m_eivalues.cwiseAbs().tail(n-i).minCoeff(&k); + if (k != 0) + { + k += i; + std::swap(m_eivalues[k],m_eivalues[i]); + if(computeEigenvectors) + m_eivec.col(i).swap(m_eivec.col(k)); + } + } +} + +} // end namespace Eigen + +#endif // EIGEN_COMPLEX_EIGEN_SOLVER_H |