cart-elc

Source code for CART-ELC
git clone git://git.laack.co/cart-elc.git
Log | Files | Refs | README | LICENSE

ArpackSelfAdjointEigenSolver.h (29075B)


      1 // This file is part of Eigen, a lightweight C++ template library
      2 // for linear algebra.
      3 //
      4 // Copyright (C) 2012 David Harmon <dharmon@gmail.com>
      5 //
      6 // This Source Code Form is subject to the terms of the Mozilla
      7 // Public License v. 2.0. If a copy of the MPL was not distributed
      8 // with this file, You can obtain one at http://mozilla.org/MPL/2.0/.
      9 
     10 #ifndef EIGEN_ARPACKGENERALIZEDSELFADJOINTEIGENSOLVER_H
     11 #define EIGEN_ARPACKGENERALIZEDSELFADJOINTEIGENSOLVER_H
     12 
     13 #include "../../../../Eigen/Dense"
     14 
     15 namespace Eigen { 
     16 
     17 namespace internal {
     18   template<typename Scalar, typename RealScalar> struct arpack_wrapper;
     19   template<typename MatrixSolver, typename MatrixType, typename Scalar, bool BisSPD> struct OP;
     20 }
     21 
     22 
     23 
     24 template<typename MatrixType, typename MatrixSolver=SimplicialLLT<MatrixType>, bool BisSPD=false>
     25 class ArpackGeneralizedSelfAdjointEigenSolver
     26 {
     27 public:
     28   //typedef typename MatrixSolver::MatrixType MatrixType;
     29 
     30   /** \brief Scalar type for matrices of type \p MatrixType. */
     31   typedef typename MatrixType::Scalar Scalar;
     32   typedef typename MatrixType::Index Index;
     33 
     34   /** \brief Real scalar type for \p MatrixType.
     35    *
     36    * This is just \c Scalar if #Scalar is real (e.g., \c float or
     37    * \c Scalar), and the type of the real part of \c Scalar if #Scalar is
     38    * complex.
     39    */
     40   typedef typename NumTraits<Scalar>::Real RealScalar;
     41 
     42   /** \brief Type for vector of eigenvalues as returned by eigenvalues().
     43    *
     44    * This is a column vector with entries of type #RealScalar.
     45    * The length of the vector is the size of \p nbrEigenvalues.
     46    */
     47   typedef typename internal::plain_col_type<MatrixType, RealScalar>::type RealVectorType;
     48 
     49   /** \brief Default constructor.
     50    *
     51    * The default constructor is for cases in which the user intends to
     52    * perform decompositions via compute().
     53    *
     54    */
     55   ArpackGeneralizedSelfAdjointEigenSolver()
     56    : m_eivec(),
     57      m_eivalues(),
     58      m_isInitialized(false),
     59      m_eigenvectorsOk(false),
     60      m_nbrConverged(0),
     61      m_nbrIterations(0)
     62   { }
     63 
     64   /** \brief Constructor; computes generalized eigenvalues of given matrix with respect to another matrix.
     65    *
     66    * \param[in] A Self-adjoint matrix whose eigenvalues / eigenvectors will
     67    *    computed. By default, the upper triangular part is used, but can be changed
     68    *    through the template parameter.
     69    * \param[in] B Self-adjoint matrix for the generalized eigenvalue problem.
     70    * \param[in] nbrEigenvalues The number of eigenvalues / eigenvectors to compute.
     71    *    Must be less than the size of the input matrix, or an error is returned.
     72    * \param[in] eigs_sigma String containing either "LM", "SM", "LA", or "SA", with
     73    *    respective meanings to find the largest magnitude , smallest magnitude,
     74    *    largest algebraic, or smallest algebraic eigenvalues. Alternatively, this
     75    *    value can contain floating point value in string form, in which case the
     76    *    eigenvalues closest to this value will be found.
     77    * \param[in]  options Can be #ComputeEigenvectors (default) or #EigenvaluesOnly.
     78    * \param[in] tol What tolerance to find the eigenvalues to. Default is 0, which
     79    *    means machine precision.
     80    *
     81    * This constructor calls compute(const MatrixType&, const MatrixType&, Index, string, int, RealScalar)
     82    * to compute the eigenvalues of the matrix \p A with respect to \p B. The eigenvectors are computed if
     83    * \p options equals #ComputeEigenvectors.
     84    *
     85    */
     86   ArpackGeneralizedSelfAdjointEigenSolver(const MatrixType& A, const MatrixType& B,
     87                                           Index nbrEigenvalues, std::string eigs_sigma="LM",
     88                                int options=ComputeEigenvectors, RealScalar tol=0.0)
     89     : m_eivec(),
     90       m_eivalues(),
     91       m_isInitialized(false),
     92       m_eigenvectorsOk(false),
     93       m_nbrConverged(0),
     94       m_nbrIterations(0)
     95   {
     96     compute(A, B, nbrEigenvalues, eigs_sigma, options, tol);
     97   }
     98 
     99   /** \brief Constructor; computes eigenvalues of given matrix.
    100    *
    101    * \param[in] A Self-adjoint matrix whose eigenvalues / eigenvectors will
    102    *    computed. By default, the upper triangular part is used, but can be changed
    103    *    through the template parameter.
    104    * \param[in] nbrEigenvalues The number of eigenvalues / eigenvectors to compute.
    105    *    Must be less than the size of the input matrix, or an error is returned.
    106    * \param[in] eigs_sigma String containing either "LM", "SM", "LA", or "SA", with
    107    *    respective meanings to find the largest magnitude , smallest magnitude,
    108    *    largest algebraic, or smallest algebraic eigenvalues. Alternatively, this
    109    *    value can contain floating point value in string form, in which case the
    110    *    eigenvalues closest to this value will be found.
    111    * \param[in]  options Can be #ComputeEigenvectors (default) or #EigenvaluesOnly.
    112    * \param[in] tol What tolerance to find the eigenvalues to. Default is 0, which
    113    *    means machine precision.
    114    *
    115    * This constructor calls compute(const MatrixType&, Index, string, int, RealScalar)
    116    * to compute the eigenvalues of the matrix \p A. The eigenvectors are computed if
    117    * \p options equals #ComputeEigenvectors.
    118    *
    119    */
    120 
    121   ArpackGeneralizedSelfAdjointEigenSolver(const MatrixType& A,
    122                                           Index nbrEigenvalues, std::string eigs_sigma="LM",
    123                                int options=ComputeEigenvectors, RealScalar tol=0.0)
    124     : m_eivec(),
    125       m_eivalues(),
    126       m_isInitialized(false),
    127       m_eigenvectorsOk(false),
    128       m_nbrConverged(0),
    129       m_nbrIterations(0)
    130   {
    131     compute(A, nbrEigenvalues, eigs_sigma, options, tol);
    132   }
    133 
    134 
    135   /** \brief Computes generalized eigenvalues / eigenvectors of given matrix using the external ARPACK library.
    136    *
    137    * \param[in]  A  Selfadjoint matrix whose eigendecomposition is to be computed.
    138    * \param[in]  B  Selfadjoint matrix for generalized eigenvalues.
    139    * \param[in] nbrEigenvalues The number of eigenvalues / eigenvectors to compute.
    140    *    Must be less than the size of the input matrix, or an error is returned.
    141    * \param[in] eigs_sigma String containing either "LM", "SM", "LA", or "SA", with
    142    *    respective meanings to find the largest magnitude , smallest magnitude,
    143    *    largest algebraic, or smallest algebraic eigenvalues. Alternatively, this
    144    *    value can contain floating point value in string form, in which case the
    145    *    eigenvalues closest to this value will be found.
    146    * \param[in]  options Can be #ComputeEigenvectors (default) or #EigenvaluesOnly.
    147    * \param[in] tol What tolerance to find the eigenvalues to. Default is 0, which
    148    *    means machine precision.
    149    *
    150    * \returns    Reference to \c *this
    151    *
    152    * This function computes the generalized eigenvalues of \p A with respect to \p B using ARPACK.  The eigenvalues()
    153    * function can be used to retrieve them.  If \p options equals #ComputeEigenvectors,
    154    * then the eigenvectors are also computed and can be retrieved by
    155    * calling eigenvectors().
    156    *
    157    */
    158   ArpackGeneralizedSelfAdjointEigenSolver& compute(const MatrixType& A, const MatrixType& B,
    159                                                    Index nbrEigenvalues, std::string eigs_sigma="LM",
    160                                         int options=ComputeEigenvectors, RealScalar tol=0.0);
    161   
    162   /** \brief Computes eigenvalues / eigenvectors of given matrix using the external ARPACK library.
    163    *
    164    * \param[in]  A  Selfadjoint matrix whose eigendecomposition is to be computed.
    165    * \param[in] nbrEigenvalues The number of eigenvalues / eigenvectors to compute.
    166    *    Must be less than the size of the input matrix, or an error is returned.
    167    * \param[in] eigs_sigma String containing either "LM", "SM", "LA", or "SA", with
    168    *    respective meanings to find the largest magnitude , smallest magnitude,
    169    *    largest algebraic, or smallest algebraic eigenvalues. Alternatively, this
    170    *    value can contain floating point value in string form, in which case the
    171    *    eigenvalues closest to this value will be found.
    172    * \param[in]  options Can be #ComputeEigenvectors (default) or #EigenvaluesOnly.
    173    * \param[in] tol What tolerance to find the eigenvalues to. Default is 0, which
    174    *    means machine precision.
    175    *
    176    * \returns    Reference to \c *this
    177    *
    178    * This function computes the eigenvalues of \p A using ARPACK.  The eigenvalues()
    179    * function can be used to retrieve them.  If \p options equals #ComputeEigenvectors,
    180    * then the eigenvectors are also computed and can be retrieved by
    181    * calling eigenvectors().
    182    *
    183    */
    184   ArpackGeneralizedSelfAdjointEigenSolver& compute(const MatrixType& A,
    185                                                    Index nbrEigenvalues, std::string eigs_sigma="LM",
    186                                         int options=ComputeEigenvectors, RealScalar tol=0.0);
    187 
    188 
    189   /** \brief Returns the eigenvectors of given matrix.
    190    *
    191    * \returns  A const reference to the matrix whose columns are the eigenvectors.
    192    *
    193    * \pre The eigenvectors have been computed before.
    194    *
    195    * Column \f$ k \f$ of the returned matrix is an eigenvector corresponding
    196    * to eigenvalue number \f$ k \f$ as returned by eigenvalues().  The
    197    * eigenvectors are normalized to have (Euclidean) norm equal to one. If
    198    * this object was used to solve the eigenproblem for the selfadjoint
    199    * matrix \f$ A \f$, then the matrix returned by this function is the
    200    * matrix \f$ V \f$ in the eigendecomposition \f$ A V = D V \f$.
    201    * For the generalized eigenproblem, the matrix returned is the solution \f$ A V = D B V \f$
    202    *
    203    * Example: \include SelfAdjointEigenSolver_eigenvectors.cpp
    204    * Output: \verbinclude SelfAdjointEigenSolver_eigenvectors.out
    205    *
    206    * \sa eigenvalues()
    207    */
    208   const Matrix<Scalar, Dynamic, Dynamic>& eigenvectors() const
    209   {
    210     eigen_assert(m_isInitialized && "ArpackGeneralizedSelfAdjointEigenSolver is not initialized.");
    211     eigen_assert(m_eigenvectorsOk && "The eigenvectors have not been computed together with the eigenvalues.");
    212     return m_eivec;
    213   }
    214 
    215   /** \brief Returns the eigenvalues of given matrix.
    216    *
    217    * \returns A const reference to the column vector containing the eigenvalues.
    218    *
    219    * \pre The eigenvalues have been computed before.
    220    *
    221    * The eigenvalues are repeated according to their algebraic multiplicity,
    222    * so there are as many eigenvalues as rows in the matrix. The eigenvalues
    223    * are sorted in increasing order.
    224    *
    225    * Example: \include SelfAdjointEigenSolver_eigenvalues.cpp
    226    * Output: \verbinclude SelfAdjointEigenSolver_eigenvalues.out
    227    *
    228    * \sa eigenvectors(), MatrixBase::eigenvalues()
    229    */
    230   const Matrix<Scalar, Dynamic, 1>& eigenvalues() const
    231   {
    232     eigen_assert(m_isInitialized && "ArpackGeneralizedSelfAdjointEigenSolver is not initialized.");
    233     return m_eivalues;
    234   }
    235 
    236   /** \brief Computes the positive-definite square root of the matrix.
    237    *
    238    * \returns the positive-definite square root of the matrix
    239    *
    240    * \pre The eigenvalues and eigenvectors of a positive-definite matrix
    241    * have been computed before.
    242    *
    243    * The square root of a positive-definite matrix \f$ A \f$ is the
    244    * positive-definite matrix whose square equals \f$ A \f$. This function
    245    * uses the eigendecomposition \f$ A = V D V^{-1} \f$ to compute the
    246    * square root as \f$ A^{1/2} = V D^{1/2} V^{-1} \f$.
    247    *
    248    * Example: \include SelfAdjointEigenSolver_operatorSqrt.cpp
    249    * Output: \verbinclude SelfAdjointEigenSolver_operatorSqrt.out
    250    *
    251    * \sa operatorInverseSqrt(),
    252    *     \ref MatrixFunctions_Module "MatrixFunctions Module"
    253    */
    254   Matrix<Scalar, Dynamic, Dynamic> operatorSqrt() const
    255   {
    256     eigen_assert(m_isInitialized && "SelfAdjointEigenSolver is not initialized.");
    257     eigen_assert(m_eigenvectorsOk && "The eigenvectors have not been computed together with the eigenvalues.");
    258     return m_eivec * m_eivalues.cwiseSqrt().asDiagonal() * m_eivec.adjoint();
    259   }
    260 
    261   /** \brief Computes the inverse square root of the matrix.
    262    *
    263    * \returns the inverse positive-definite square root of the matrix
    264    *
    265    * \pre The eigenvalues and eigenvectors of a positive-definite matrix
    266    * have been computed before.
    267    *
    268    * This function uses the eigendecomposition \f$ A = V D V^{-1} \f$ to
    269    * compute the inverse square root as \f$ V D^{-1/2} V^{-1} \f$. This is
    270    * cheaper than first computing the square root with operatorSqrt() and
    271    * then its inverse with MatrixBase::inverse().
    272    *
    273    * Example: \include SelfAdjointEigenSolver_operatorInverseSqrt.cpp
    274    * Output: \verbinclude SelfAdjointEigenSolver_operatorInverseSqrt.out
    275    *
    276    * \sa operatorSqrt(), MatrixBase::inverse(),
    277    *     \ref MatrixFunctions_Module "MatrixFunctions Module"
    278    */
    279   Matrix<Scalar, Dynamic, Dynamic> operatorInverseSqrt() const
    280   {
    281     eigen_assert(m_isInitialized && "SelfAdjointEigenSolver is not initialized.");
    282     eigen_assert(m_eigenvectorsOk && "The eigenvectors have not been computed together with the eigenvalues.");
    283     return m_eivec * m_eivalues.cwiseInverse().cwiseSqrt().asDiagonal() * m_eivec.adjoint();
    284   }
    285 
    286   /** \brief Reports whether previous computation was successful.
    287    *
    288    * \returns \c Success if computation was successful, \c NoConvergence otherwise.
    289    */
    290   ComputationInfo info() const
    291   {
    292     eigen_assert(m_isInitialized && "ArpackGeneralizedSelfAdjointEigenSolver is not initialized.");
    293     return m_info;
    294   }
    295 
    296   size_t getNbrConvergedEigenValues() const
    297   { return m_nbrConverged; }
    298 
    299   size_t getNbrIterations() const
    300   { return m_nbrIterations; }
    301 
    302 protected:
    303   Matrix<Scalar, Dynamic, Dynamic> m_eivec;
    304   Matrix<Scalar, Dynamic, 1> m_eivalues;
    305   ComputationInfo m_info;
    306   bool m_isInitialized;
    307   bool m_eigenvectorsOk;
    308 
    309   size_t m_nbrConverged;
    310   size_t m_nbrIterations;
    311 };
    312 
    313 
    314 
    315 
    316 
    317 template<typename MatrixType, typename MatrixSolver, bool BisSPD>
    318 ArpackGeneralizedSelfAdjointEigenSolver<MatrixType, MatrixSolver, BisSPD>&
    319     ArpackGeneralizedSelfAdjointEigenSolver<MatrixType, MatrixSolver, BisSPD>
    320 ::compute(const MatrixType& A, Index nbrEigenvalues,
    321           std::string eigs_sigma, int options, RealScalar tol)
    322 {
    323     MatrixType B(0,0);
    324     compute(A, B, nbrEigenvalues, eigs_sigma, options, tol);
    325     
    326     return *this;
    327 }
    328 
    329 
    330 template<typename MatrixType, typename MatrixSolver, bool BisSPD>
    331 ArpackGeneralizedSelfAdjointEigenSolver<MatrixType, MatrixSolver, BisSPD>&
    332     ArpackGeneralizedSelfAdjointEigenSolver<MatrixType, MatrixSolver, BisSPD>
    333 ::compute(const MatrixType& A, const MatrixType& B, Index nbrEigenvalues,
    334           std::string eigs_sigma, int options, RealScalar tol)
    335 {
    336   eigen_assert(A.cols() == A.rows());
    337   eigen_assert(B.cols() == B.rows());
    338   eigen_assert(B.rows() == 0 || A.cols() == B.rows());
    339   eigen_assert((options &~ (EigVecMask | GenEigMask)) == 0
    340             && (options & EigVecMask) != EigVecMask
    341             && "invalid option parameter");
    342 
    343   bool isBempty = (B.rows() == 0) || (B.cols() == 0);
    344 
    345   // For clarity, all parameters match their ARPACK name
    346   //
    347   // Always 0 on the first call
    348   //
    349   int ido = 0;
    350 
    351   int n = (int)A.cols();
    352 
    353   // User options: "LA", "SA", "SM", "LM", "BE"
    354   //
    355   char whch[3] = "LM";
    356     
    357   // Specifies the shift if iparam[6] = { 3, 4, 5 }, not used if iparam[6] = { 1, 2 }
    358   //
    359   RealScalar sigma = 0.0;
    360 
    361   if (eigs_sigma.length() >= 2 && isalpha(eigs_sigma[0]) && isalpha(eigs_sigma[1]))
    362   {
    363       eigs_sigma[0] = toupper(eigs_sigma[0]);
    364       eigs_sigma[1] = toupper(eigs_sigma[1]);
    365 
    366       // In the following special case we're going to invert the problem, since solving
    367       // for larger magnitude is much much faster
    368       // i.e., if 'SM' is specified, we're going to really use 'LM', the default
    369       //
    370       if (eigs_sigma.substr(0,2) != "SM")
    371       {
    372           whch[0] = eigs_sigma[0];
    373           whch[1] = eigs_sigma[1];
    374       }
    375   }
    376   else
    377   {
    378       eigen_assert(false && "Specifying clustered eigenvalues is not yet supported!");
    379 
    380       // If it's not scalar values, then the user may be explicitly
    381       // specifying the sigma value to cluster the evs around
    382       //
    383       sigma = atof(eigs_sigma.c_str());
    384 
    385       // If atof fails, it returns 0.0, which is a fine default
    386       //
    387   }
    388 
    389   // "I" means normal eigenvalue problem, "G" means generalized
    390   //
    391   char bmat[2] = "I";
    392   if (eigs_sigma.substr(0,2) == "SM" || !(isalpha(eigs_sigma[0]) && isalpha(eigs_sigma[1])) || (!isBempty && !BisSPD))
    393       bmat[0] = 'G';
    394 
    395   // Now we determine the mode to use
    396   //
    397   int mode = (bmat[0] == 'G') + 1;
    398   if (eigs_sigma.substr(0,2) == "SM" || !(isalpha(eigs_sigma[0]) && isalpha(eigs_sigma[1])))
    399   {
    400       // We're going to use shift-and-invert mode, and basically find
    401       // the largest eigenvalues of the inverse operator
    402       //
    403       mode = 3;
    404   }
    405 
    406   // The user-specified number of eigenvalues/vectors to compute
    407   //
    408   int nev = (int)nbrEigenvalues;
    409 
    410   // Allocate space for ARPACK to store the residual
    411   //
    412   Scalar *resid = new Scalar[n];
    413 
    414   // Number of Lanczos vectors, must satisfy nev < ncv <= n
    415   // Note that this indicates that nev != n, and we cannot compute
    416   // all eigenvalues of a mtrix
    417   //
    418   int ncv = std::min(std::max(2*nev, 20), n);
    419 
    420   // The working n x ncv matrix, also store the final eigenvectors (if computed)
    421   //
    422   Scalar *v = new Scalar[n*ncv];
    423   int ldv = n;
    424 
    425   // Working space
    426   //
    427   Scalar *workd = new Scalar[3*n];
    428   int lworkl = ncv*ncv+8*ncv; // Must be at least this length
    429   Scalar *workl = new Scalar[lworkl];
    430 
    431   int *iparam= new int[11];
    432   iparam[0] = 1; // 1 means we let ARPACK perform the shifts, 0 means we'd have to do it
    433   iparam[2] = std::max(300, (int)std::ceil(2*n/std::max(ncv,1)));
    434   iparam[6] = mode; // The mode, 1 is standard ev problem, 2 for generalized ev, 3 for shift-and-invert
    435 
    436   // Used during reverse communicate to notify where arrays start
    437   //
    438   int *ipntr = new int[11]; 
    439 
    440   // Error codes are returned in here, initial value of 0 indicates a random initial
    441   // residual vector is used, any other values means resid contains the initial residual
    442   // vector, possibly from a previous run
    443   //
    444   int info = 0;
    445 
    446   Scalar scale = 1.0;
    447   //if (!isBempty)
    448   //{
    449   //Scalar scale = B.norm() / std::sqrt(n);
    450   //scale = std::pow(2, std::floor(std::log(scale+1)));
    451   ////M /= scale;
    452   //for (size_t i=0; i<(size_t)B.outerSize(); i++)
    453   //    for (typename MatrixType::InnerIterator it(B, i); it; ++it)
    454   //        it.valueRef() /= scale;
    455   //}
    456 
    457   MatrixSolver OP;
    458   if (mode == 1 || mode == 2)
    459   {
    460       if (!isBempty)
    461           OP.compute(B);
    462   }
    463   else if (mode == 3)
    464   {
    465       if (sigma == 0.0)
    466       {
    467           OP.compute(A);
    468       }
    469       else
    470       {
    471           // Note: We will never enter here because sigma must be 0.0
    472           //
    473           if (isBempty)
    474           {
    475             MatrixType AminusSigmaB(A);
    476             for (Index i=0; i<A.rows(); ++i)
    477                 AminusSigmaB.coeffRef(i,i) -= sigma;
    478             
    479             OP.compute(AminusSigmaB);
    480           }
    481           else
    482           {
    483               MatrixType AminusSigmaB = A - sigma * B;
    484               OP.compute(AminusSigmaB);
    485           }
    486       }
    487   }
    488  
    489   if (!(mode == 1 && isBempty) && !(mode == 2 && isBempty) && OP.info() != Success)
    490       std::cout << "Error factoring matrix" << std::endl;
    491 
    492   do
    493   {
    494     internal::arpack_wrapper<Scalar, RealScalar>::saupd(&ido, bmat, &n, whch, &nev, &tol, resid, 
    495                                                         &ncv, v, &ldv, iparam, ipntr, workd, workl,
    496                                                         &lworkl, &info);
    497 
    498     if (ido == -1 || ido == 1)
    499     {
    500       Scalar *in  = workd + ipntr[0] - 1;
    501       Scalar *out = workd + ipntr[1] - 1;
    502 
    503       if (ido == 1 && mode != 2)
    504       {
    505           Scalar *out2 = workd + ipntr[2] - 1;
    506           if (isBempty || mode == 1)
    507             Matrix<Scalar, Dynamic, 1>::Map(out2, n) = Matrix<Scalar, Dynamic, 1>::Map(in, n);
    508           else
    509             Matrix<Scalar, Dynamic, 1>::Map(out2, n) = B * Matrix<Scalar, Dynamic, 1>::Map(in, n);
    510           
    511           in = workd + ipntr[2] - 1;
    512       }
    513 
    514       if (mode == 1)
    515       {
    516         if (isBempty)
    517         {
    518           // OP = A
    519           //
    520           Matrix<Scalar, Dynamic, 1>::Map(out, n) = A * Matrix<Scalar, Dynamic, 1>::Map(in, n);
    521         }
    522         else
    523         {
    524           // OP = L^{-1}AL^{-T}
    525           //
    526           internal::OP<MatrixSolver, MatrixType, Scalar, BisSPD>::applyOP(OP, A, n, in, out);
    527         }
    528       }
    529       else if (mode == 2)
    530       {
    531         if (ido == 1)
    532           Matrix<Scalar, Dynamic, 1>::Map(in, n)  = A * Matrix<Scalar, Dynamic, 1>::Map(in, n);
    533         
    534         // OP = B^{-1} A
    535         //
    536         Matrix<Scalar, Dynamic, 1>::Map(out, n) = OP.solve(Matrix<Scalar, Dynamic, 1>::Map(in, n));
    537       }
    538       else if (mode == 3)
    539       {
    540         // OP = (A-\sigmaB)B (\sigma could be 0, and B could be I)
    541         // The B * in is already computed and stored at in if ido == 1
    542         //
    543         if (ido == 1 || isBempty)
    544           Matrix<Scalar, Dynamic, 1>::Map(out, n) = OP.solve(Matrix<Scalar, Dynamic, 1>::Map(in, n));
    545         else
    546           Matrix<Scalar, Dynamic, 1>::Map(out, n) = OP.solve(B * Matrix<Scalar, Dynamic, 1>::Map(in, n));
    547       }
    548     }
    549     else if (ido == 2)
    550     {
    551       Scalar *in  = workd + ipntr[0] - 1;
    552       Scalar *out = workd + ipntr[1] - 1;
    553 
    554       if (isBempty || mode == 1)
    555         Matrix<Scalar, Dynamic, 1>::Map(out, n) = Matrix<Scalar, Dynamic, 1>::Map(in, n);
    556       else
    557         Matrix<Scalar, Dynamic, 1>::Map(out, n) = B * Matrix<Scalar, Dynamic, 1>::Map(in, n);
    558     }
    559   } while (ido != 99);
    560 
    561   if (info == 1)
    562     m_info = NoConvergence;
    563   else if (info == 3)
    564     m_info = NumericalIssue;
    565   else if (info < 0)
    566     m_info = InvalidInput;
    567   else if (info != 0)
    568     eigen_assert(false && "Unknown ARPACK return value!");
    569   else
    570   {
    571     // Do we compute eigenvectors or not?
    572     //
    573     int rvec = (options & ComputeEigenvectors) == ComputeEigenvectors;
    574 
    575     // "A" means "All", use "S" to choose specific eigenvalues (not yet supported in ARPACK))
    576     //
    577     char howmny[2] = "A"; 
    578 
    579     // if howmny == "S", specifies the eigenvalues to compute (not implemented in ARPACK)
    580     //
    581     int *select = new int[ncv];
    582 
    583     // Final eigenvalues
    584     //
    585     m_eivalues.resize(nev, 1);
    586 
    587     internal::arpack_wrapper<Scalar, RealScalar>::seupd(&rvec, howmny, select, m_eivalues.data(), v, &ldv,
    588                                                         &sigma, bmat, &n, whch, &nev, &tol, resid, &ncv,
    589                                                         v, &ldv, iparam, ipntr, workd, workl, &lworkl, &info);
    590 
    591     if (info == -14)
    592       m_info = NoConvergence;
    593     else if (info != 0)
    594       m_info = InvalidInput;
    595     else
    596     {
    597       if (rvec)
    598       {
    599         m_eivec.resize(A.rows(), nev);
    600         for (int i=0; i<nev; i++)
    601           for (int j=0; j<n; j++)
    602             m_eivec(j,i) = v[i*n+j] / scale;
    603       
    604         if (mode == 1 && !isBempty && BisSPD)
    605           internal::OP<MatrixSolver, MatrixType, Scalar, BisSPD>::project(OP, n, nev, m_eivec.data());
    606 
    607         m_eigenvectorsOk = true;
    608       }
    609 
    610       m_nbrIterations = iparam[2];
    611       m_nbrConverged  = iparam[4];
    612 
    613       m_info = Success;
    614     }
    615 
    616     delete[] select;
    617   }
    618 
    619   delete[] v;
    620   delete[] iparam;
    621   delete[] ipntr;
    622   delete[] workd;
    623   delete[] workl;
    624   delete[] resid;
    625 
    626   m_isInitialized = true;
    627 
    628   return *this;
    629 }
    630 
    631 
    632 // Single precision
    633 //
    634 extern "C" void ssaupd_(int *ido, char *bmat, int *n, char *which,
    635     int *nev, float *tol, float *resid, int *ncv,
    636     float *v, int *ldv, int *iparam, int *ipntr,
    637     float *workd, float *workl, int *lworkl,
    638     int *info);
    639 
    640 extern "C" void sseupd_(int *rvec, char *All, int *select, float *d,
    641     float *z, int *ldz, float *sigma, 
    642     char *bmat, int *n, char *which, int *nev,
    643     float *tol, float *resid, int *ncv, float *v,
    644     int *ldv, int *iparam, int *ipntr, float *workd,
    645     float *workl, int *lworkl, int *ierr);
    646 
    647 // Double precision
    648 //
    649 extern "C" void dsaupd_(int *ido, char *bmat, int *n, char *which,
    650     int *nev, double *tol, double *resid, int *ncv,
    651     double *v, int *ldv, int *iparam, int *ipntr,
    652     double *workd, double *workl, int *lworkl,
    653     int *info);
    654 
    655 extern "C" void dseupd_(int *rvec, char *All, int *select, double *d,
    656     double *z, int *ldz, double *sigma, 
    657     char *bmat, int *n, char *which, int *nev,
    658     double *tol, double *resid, int *ncv, double *v,
    659     int *ldv, int *iparam, int *ipntr, double *workd,
    660     double *workl, int *lworkl, int *ierr);
    661 
    662 
    663 namespace internal {
    664 
    665 template<typename Scalar, typename RealScalar> struct arpack_wrapper
    666 {
    667   static inline void saupd(int *ido, char *bmat, int *n, char *which,
    668       int *nev, RealScalar *tol, Scalar *resid, int *ncv,
    669       Scalar *v, int *ldv, int *iparam, int *ipntr,
    670       Scalar *workd, Scalar *workl, int *lworkl, int *info)
    671   { 
    672     EIGEN_STATIC_ASSERT(!NumTraits<Scalar>::IsComplex, NUMERIC_TYPE_MUST_BE_REAL)
    673   }
    674 
    675   static inline void seupd(int *rvec, char *All, int *select, Scalar *d,
    676       Scalar *z, int *ldz, RealScalar *sigma,
    677       char *bmat, int *n, char *which, int *nev,
    678       RealScalar *tol, Scalar *resid, int *ncv, Scalar *v,
    679       int *ldv, int *iparam, int *ipntr, Scalar *workd,
    680       Scalar *workl, int *lworkl, int *ierr)
    681   {
    682     EIGEN_STATIC_ASSERT(!NumTraits<Scalar>::IsComplex, NUMERIC_TYPE_MUST_BE_REAL)
    683   }
    684 };
    685 
    686 template <> struct arpack_wrapper<float, float>
    687 {
    688   static inline void saupd(int *ido, char *bmat, int *n, char *which,
    689       int *nev, float *tol, float *resid, int *ncv,
    690       float *v, int *ldv, int *iparam, int *ipntr,
    691       float *workd, float *workl, int *lworkl, int *info)
    692   {
    693     ssaupd_(ido, bmat, n, which, nev, tol, resid, ncv, v, ldv, iparam, ipntr, workd, workl, lworkl, info);
    694   }
    695 
    696   static inline void seupd(int *rvec, char *All, int *select, float *d,
    697       float *z, int *ldz, float *sigma,
    698       char *bmat, int *n, char *which, int *nev,
    699       float *tol, float *resid, int *ncv, float *v,
    700       int *ldv, int *iparam, int *ipntr, float *workd,
    701       float *workl, int *lworkl, int *ierr)
    702   {
    703     sseupd_(rvec, All, select, d, z, ldz, sigma, bmat, n, which, nev, tol, resid, ncv, v, ldv, iparam, ipntr,
    704         workd, workl, lworkl, ierr);
    705   }
    706 };
    707 
    708 template <> struct arpack_wrapper<double, double>
    709 {
    710   static inline void saupd(int *ido, char *bmat, int *n, char *which,
    711       int *nev, double *tol, double *resid, int *ncv,
    712       double *v, int *ldv, int *iparam, int *ipntr,
    713       double *workd, double *workl, int *lworkl, int *info)
    714   {
    715     dsaupd_(ido, bmat, n, which, nev, tol, resid, ncv, v, ldv, iparam, ipntr, workd, workl, lworkl, info);
    716   }
    717 
    718   static inline void seupd(int *rvec, char *All, int *select, double *d,
    719       double *z, int *ldz, double *sigma,
    720       char *bmat, int *n, char *which, int *nev,
    721       double *tol, double *resid, int *ncv, double *v,
    722       int *ldv, int *iparam, int *ipntr, double *workd,
    723       double *workl, int *lworkl, int *ierr)
    724   {
    725     dseupd_(rvec, All, select, d, v, ldv, sigma, bmat, n, which, nev, tol, resid, ncv, v, ldv, iparam, ipntr,
    726         workd, workl, lworkl, ierr);
    727   }
    728 };
    729 
    730 
    731 template<typename MatrixSolver, typename MatrixType, typename Scalar, bool BisSPD>
    732 struct OP
    733 {
    734     static inline void applyOP(MatrixSolver &OP, const MatrixType &A, int n, Scalar *in, Scalar *out);
    735     static inline void project(MatrixSolver &OP, int n, int k, Scalar *vecs);
    736 };
    737 
    738 template<typename MatrixSolver, typename MatrixType, typename Scalar>
    739 struct OP<MatrixSolver, MatrixType, Scalar, true>
    740 {
    741   static inline void applyOP(MatrixSolver &OP, const MatrixType &A, int n, Scalar *in, Scalar *out)
    742 {
    743     // OP = L^{-1} A L^{-T}  (B = LL^T)
    744     //
    745     // First solve L^T out = in
    746     //
    747     Matrix<Scalar, Dynamic, 1>::Map(out, n) = OP.matrixU().solve(Matrix<Scalar, Dynamic, 1>::Map(in, n));
    748     Matrix<Scalar, Dynamic, 1>::Map(out, n) = OP.permutationPinv() * Matrix<Scalar, Dynamic, 1>::Map(out, n);
    749 
    750     // Then compute out = A out
    751     //
    752     Matrix<Scalar, Dynamic, 1>::Map(out, n) = A * Matrix<Scalar, Dynamic, 1>::Map(out, n);
    753 
    754     // Then solve L out = out
    755     //
    756     Matrix<Scalar, Dynamic, 1>::Map(out, n) = OP.permutationP() * Matrix<Scalar, Dynamic, 1>::Map(out, n);
    757     Matrix<Scalar, Dynamic, 1>::Map(out, n) = OP.matrixL().solve(Matrix<Scalar, Dynamic, 1>::Map(out, n));
    758 }
    759 
    760   static inline void project(MatrixSolver &OP, int n, int k, Scalar *vecs)
    761 {
    762     // Solve L^T out = in
    763     //
    764     Matrix<Scalar, Dynamic, Dynamic>::Map(vecs, n, k) = OP.matrixU().solve(Matrix<Scalar, Dynamic, Dynamic>::Map(vecs, n, k));
    765     Matrix<Scalar, Dynamic, Dynamic>::Map(vecs, n, k) = OP.permutationPinv() * Matrix<Scalar, Dynamic, Dynamic>::Map(vecs, n, k);
    766 }
    767 
    768 };
    769 
    770 template<typename MatrixSolver, typename MatrixType, typename Scalar>
    771 struct OP<MatrixSolver, MatrixType, Scalar, false>
    772 {
    773   static inline void applyOP(MatrixSolver &OP, const MatrixType &A, int n, Scalar *in, Scalar *out)
    774 {
    775     eigen_assert(false && "Should never be in here...");
    776 }
    777 
    778   static inline void project(MatrixSolver &OP, int n, int k, Scalar *vecs)
    779 {
    780     eigen_assert(false && "Should never be in here...");
    781 }
    782 
    783 };
    784 
    785 } // end namespace internal
    786 
    787 } // end namespace Eigen
    788 
    789 #endif // EIGEN_ARPACKSELFADJOINTEIGENSOLVER_H
    790