/usr/include/trilinos/BelosGmresPolySolMgr.hpp

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#ifndef BELOS_GMRES_POLY_SOLMGR_HPP
#define BELOS_GMRES_POLY_SOLMGR_HPP

/// \file BelosGmresPolySolMgr.hpp
/// \brief Declaration and definition of Belos::GmresPolySolMgr
///   (hybrid block GMRES linear solver).

#include "BelosConfigDefs.hpp"
#include "BelosTypes.hpp"

#include "BelosLinearProblem.hpp"
#include "BelosSolverManager.hpp"

#include "BelosGmresPolyOp.hpp"
#include "BelosGmresIteration.hpp"
#include "BelosBlockGmresIter.hpp"
#include "BelosDGKSOrthoManager.hpp"
#include "BelosICGSOrthoManager.hpp"
#include "BelosIMGSOrthoManager.hpp"
#include "BelosStatusTestMaxIters.hpp"
#include "BelosStatusTestGenResNorm.hpp"
#include "BelosStatusTestImpResNorm.hpp"
#include "BelosStatusTestCombo.hpp"
#include "BelosStatusTestOutputFactory.hpp"
#include "BelosOutputManager.hpp"
#include "Teuchos_BLAS.hpp"
#include "Teuchos_as.hpp"
#ifdef BELOS_TEUCHOS_TIME_MONITOR
#include "Teuchos_TimeMonitor.hpp"
#endif


namespace Belos {

//! @name GmresPolySolMgr Exceptions
//@{

/** \brief GmresPolySolMgrLinearProblemFailure is thrown when the linear problem is
 * not setup (i.e. setProblem() was not called) when solve() is called.
 *
 * This std::exception is thrown from the GmresPolySolMgr::solve() method.
 *
 */
class GmresPolySolMgrLinearProblemFailure : public BelosError {public:
  GmresPolySolMgrLinearProblemFailure(const std::string& what_arg) : BelosError(what_arg)
    {}};

/** \brief GmresPolySolMgrPolynomialFailure is thrown when their is a problem generating
 * the GMRES polynomial for this linear problem.
 *
 * This std::exception is thrown from the GmresPolySolMgr::solve() method.
 *
 */
class GmresPolySolMgrPolynomialFailure : public BelosError {public:
  GmresPolySolMgrPolynomialFailure(const std::string& what_arg) : BelosError(what_arg)
    {}};

/** \brief GmresPolySolMgrOrthoFailure is thrown when the orthogonalization manager is
 * unable to generate orthonormal columns from the initial basis vectors.
 *
 * This std::exception is thrown from the GmresPolySolMgr::solve() method.
 *
 */
class GmresPolySolMgrOrthoFailure : public BelosError {public:
  GmresPolySolMgrOrthoFailure(const std::string& what_arg) : BelosError(what_arg)
    {}};

/// \class Belos::GmresPolySolMgr
/// \brief Hybrid block GMRES iterative linear solver.
/// \author Heidi Thornquist
/// \ingroup belos_solver_framework
/// \example BlockGmres/BlockGmresPolyEpetraExFile.cpp
///
/// "Hybrid block GMRES" means that the solver first runs block GMRES.
/// It stores the resulting coefficients, which form a matrix
/// polynomial.  It then can reuse this polynomial for subsequent
/// solves.  This avoids the cost of the inner products and norms in
/// GMRES.  However, the resulting polynomial is not necessarily as
/// effective as the equivalent number of GMRES iterations.
///
/// We call solvers that take this approach "seed solvers."  Belos
/// implements both a Block GMRES seed solver (this class) and a
/// CG-based seed solver (Belos::PCPGSolMgr).
///
/// Here is a list of all the parameters that this solver accepts:
///   - "Convergence Tolerance" (\c MagnitudeType): The level that
///     residual norms must reach to decide convergence. Default:
///     1e-8.
///   - "Block Size" (\c int): The block size to be used by the
///     underlying block GMRES solver. Default: 1 (which means don't
///     use blocks).
///   - "Num Blocks" (\c int): The restart length; that is, the number
///     of blocks allocated for the Krylov basis. Default: 300.
///   - "Maximum Iterations" (\c int): The maximum number of
///     iterations GMRES is allowed to perform, across all restarts.
///     Default: 1000.
///   - "Maximum Restarts" (\c int): The maximum number of restarts
///     the underlying solver is allowed to perform.  This does
///     <i>not</i> include the first restart cycle.  Default: 20.
///   - "Orthogonalization" (\c std::string): The desired
///     orthogonalization method.  Default: "DGKS".
///   - "Verbosity" (Belos::MsgType): A sum of Belos::MsgType values
///     specifying what kinds of messages to print.  Default:
///     Belos::Errors.
///   - "Output Style" (Belos::OutputType): The output style.
///     Default: Belos::General.
///
/// Like all Belos solvers, parameters have relative or "delta"
/// semantics.  This means the following:
///   - Any parameter that was <i>never</i> set has its default value
///   - Any parameter not explicitly set in the input ParameterList
///     retains its current value
template<class ScalarType, class MV, class OP>
class GmresPolySolMgr : public SolverManager<ScalarType,MV,OP> {
private:
  typedef MultiVecTraits<ScalarType,MV> MVT;
  typedef OperatorTraits<ScalarType,MV,OP> OPT;
  typedef Teuchos::ScalarTraits<ScalarType> STS;
  typedef typename Teuchos::ScalarTraits<ScalarType>::magnitudeType MagnitudeType;
  typedef Teuchos::ScalarTraits<MagnitudeType> MT;

public:

  //! @name Constructors/Destructor
  //@{

  /*! \brief Empty constructor for GmresPolySolMgr.
   * This constructor takes no arguments and sets the default values for the solver.
   * The linear problem must be passed in using setProblem() before solve() is called on this object.
   * The solver values can be changed using setParameters().
   */
  GmresPolySolMgr();

  /*! \brief Basic constructor for GmresPolySolMgr.
   *
   * This constructor accepts the LinearProblem to be solved in addition
   * to a parameter list of options for the solver manager. These options include the following:
   *   - "Block Size" - a \c int specifying the block size to be used by the underlying block GMRES solver. Default: 1
   *   - "Num Blocks" - a \c int specifying the number of blocks allocated for the Krylov basis. Default: 300
   *   - "Maximum Iterations" - a \c int specifying the maximum number of iterations the underlying solver is allowed to perform. Default: 1000
   *   - "Maximum Restarts" - a \c int specifying the maximum number of restarts the underlying solver is allowed to perform. Default: 20
   *   - "Orthogonalization" - a \c std::string specifying the desired orthogonalization:  DGKS, ICGS, and IMGS. Default: "DGKS"
   *   - "Verbosity" - a sum of MsgType specifying the verbosity. Default: Belos::Errors
   *   - "Output Style" - a OutputType specifying the style of output. Default: Belos::General
   *   - "Convergence Tolerance" - a \c MagnitudeType specifying the level that residual norms must reach to decide convergence. Default: 1e-8
   */
  GmresPolySolMgr( const Teuchos::RCP<LinearProblem<ScalarType,MV,OP> > &problem,
    const Teuchos::RCP<Teuchos::ParameterList> &pl );

  //! Destructor.
  virtual ~GmresPolySolMgr() {};
  //@}

  //! @name Accessor methods
  //@{

  /*! \brief Get current linear problem being solved for in this object.
   */
  const LinearProblem<ScalarType,MV,OP>& getProblem() const {
    return *problem_;
  }

  /*! \brief Get a parameter list containing the valid parameters for this object.
   */
  Teuchos::RCP<const Teuchos::ParameterList> getValidParameters() const;

  /*! \brief Get a parameter list containing the current parameters for this object.
   */
  Teuchos::RCP<const Teuchos::ParameterList> getCurrentParameters() const { return params_; }

  /*! \brief Return the timers for this object.
   *
   * The timers are ordered as follows:
   *   - time spent in solve() routine
   */
  Teuchos::Array<Teuchos::RCP<Teuchos::Time> > getTimers() const {
    return Teuchos::tuple(timerSolve_, timerPoly_);
  }

  //! Get the iteration count for the most recent call to \c solve().
  int getNumIters() const {
    return numIters_;
  }

  /*! \brief Return whether a loss of accuracy was detected by this solver during the most current solve.
      \note This flag will be reset the next time solve() is called.
   */
  bool isLOADetected() const { return loaDetected_; }

  //@}

  //! @name Set methods
  //@{

  //! Set the linear problem that needs to be solved.
  void setProblem( const Teuchos::RCP<LinearProblem<ScalarType,MV,OP> > &problem ) { problem_ = problem; isSTSet_ = false; }

  //! Set the parameters the solver manager should use to solve the linear problem.
  void setParameters( const Teuchos::RCP<Teuchos::ParameterList> &params );

  //@}
  //! @name Reset methods
  //@{

  /// \brief Reset the solver.
  ///
  /// \param type [in] How to reset the solver.
  ///
  /// If type includes Belos::Problem, then reset the solver's state.
  /// This clears out the stored coefficients, so that the next call
  /// to solve() actually computes a full block GMRES solve, instead
  /// of just reusing the coefficients from the first solve.
  void reset( const ResetType type ) {
    if ((type & Belos::Problem) && ! problem_.is_null ()) {
      problem_->setProblem ();
      isPolyBuilt_ = false;  // Rebuild the GMRES polynomial
    }
  }

  //@}
  //! @name Solver application methods
  //@{

  /*! \brief This method performs possibly repeated calls to the underlying linear solver's iterate() routine
   * until the problem has been solved (as decided by the solver manager) or the solver manager decides to
   * quit.
   *
   * This method calls BlockGmresIter::iterate(), which will return either because a specially constructed status test evaluates to
   * ::Passed or an std::exception is thrown.
   *
   * A return from BlockGmresIter::iterate() signifies one of the following scenarios:
   *    - the maximum number of restarts has been exceeded. In this scenario, the current solutions to the linear system
   *      will be placed in the linear problem and return ::Unconverged.
   *    - global convergence has been met. In this case, the current solutions to the linear system will be placed in the linear
   *      problem and the solver manager will return ::Converged
   *
   * \returns ::ReturnType specifying:
   *     - ::Converged: the linear problem was solved to the specification required by the solver manager.
   *     - ::Unconverged: the linear problem was not solved to the specification desired by the solver manager.
   */
  ReturnType solve();

  //@}

  /** \name Overridden from Teuchos::Describable */
  //@{

  /** \brief Method to return description of the hybrid block GMRES solver manager */
  std::string description() const;

  //@}

private:

  // Method for checking current status test against defined linear problem.
  bool checkStatusTest();

  // Method for generating GMRES polynomial.
  bool generatePoly();

  // Linear problem.
  Teuchos::RCP<LinearProblem<ScalarType,MV,OP> > problem_;

  // Output manager.
  Teuchos::RCP<OutputManager<ScalarType> > printer_;
  Teuchos::RCP<std::ostream> outputStream_;

  // Status test.
  Teuchos::RCP<StatusTest<ScalarType,MV,OP> > sTest_;
  Teuchos::RCP<StatusTestMaxIters<ScalarType,MV,OP> > maxIterTest_;
  Teuchos::RCP<StatusTest<ScalarType,MV,OP> > convTest_;
  Teuchos::RCP<StatusTestResNorm<ScalarType,MV,OP> > expConvTest_, impConvTest_;
  Teuchos::RCP<StatusTestOutput<ScalarType,MV,OP> > outputTest_;

  // Orthogonalization manager.
  Teuchos::RCP<MatOrthoManager<ScalarType,MV,OP> > ortho_;

  // Current parameter list.
  Teuchos::RCP<Teuchos::ParameterList> params_;

  // Default solver values.
  static const MagnitudeType polytol_default_;
  static const MagnitudeType convtol_default_;
  static const MagnitudeType orthoKappa_default_;
  static const int maxDegree_default_;
  static const int maxRestarts_default_;
  static const int maxIters_default_;
  static const bool strictConvTol_default_;
  static const bool showMaxResNormOnly_default_;
  static const int blockSize_default_;
  static const int numBlocks_default_;
  static const int verbosity_default_;
  static const int outputStyle_default_;
  static const int outputFreq_default_;
  static const std::string impResScale_default_;
  static const std::string expResScale_default_;
  static const std::string label_default_;
  static const std::string orthoType_default_;
  static const Teuchos::RCP<std::ostream> outputStream_default_;

  // Current solver values.
  MagnitudeType polytol_, convtol_, orthoKappa_;
  int maxDegree_, maxRestarts_, maxIters_, numIters_;
  int blockSize_, numBlocks_, verbosity_, outputStyle_, outputFreq_;
  bool strictConvTol_, showMaxResNormOnly_;
  std::string orthoType_;
  std::string impResScale_, expResScale_;

  // Polynomial storage
  int poly_dim_;
  Teuchos::RCP<Teuchos::SerialDenseMatrix<int, ScalarType> > poly_H_, poly_y_;
  Teuchos::RCP<Teuchos::SerialDenseVector<int, ScalarType> > poly_r0_;
  Teuchos::RCP<Belos::GmresPolyOp<ScalarType, MV, OP> > poly_Op_;

  // Timers.
  std::string label_;
  Teuchos::RCP<Teuchos::Time> timerSolve_, timerPoly_;

  // Internal state variables.
  bool isPolyBuilt_;
  bool isSet_, isSTSet_, expResTest_;
  bool loaDetected_;

  //! Cached default (valid) parameters.
  mutable Teuchos::RCP<const Teuchos::ParameterList> validPL_;
};


// Default solver values.
template<class ScalarType, class MV, class OP>
const typename GmresPolySolMgr<ScalarType,MV,OP>::MagnitudeType
GmresPolySolMgr<ScalarType,MV,OP>::polytol_default_ = 1e-12;

template<class ScalarType, class MV, class OP>
const typename GmresPolySolMgr<ScalarType,MV,OP>::MagnitudeType
GmresPolySolMgr<ScalarType,MV,OP>::convtol_default_ = 1e-8;

template<class ScalarType, class MV, class OP>
const typename GmresPolySolMgr<ScalarType,MV,OP>::MagnitudeType
GmresPolySolMgr<ScalarType,MV,OP>::orthoKappa_default_ =
  -Teuchos::ScalarTraits<MagnitudeType>::one();

template<class ScalarType, class MV, class OP>
const int GmresPolySolMgr<ScalarType,MV,OP>::maxDegree_default_ = 25;

template<class ScalarType, class MV, class OP>
const int GmresPolySolMgr<ScalarType,MV,OP>::maxRestarts_default_ = 20;

template<class ScalarType, class MV, class OP>
const int GmresPolySolMgr<ScalarType,MV,OP>::maxIters_default_ = 1000;

template<class ScalarType, class MV, class OP>
const bool GmresPolySolMgr<ScalarType,MV,OP>::strictConvTol_default_ = false;

template<class ScalarType, class MV, class OP>
const bool GmresPolySolMgr<ScalarType,MV,OP>::showMaxResNormOnly_default_ = false;

template<class ScalarType, class MV, class OP>
const int GmresPolySolMgr<ScalarType,MV,OP>::blockSize_default_ = 1;

template<class ScalarType, class MV, class OP>
const int GmresPolySolMgr<ScalarType,MV,OP>::numBlocks_default_ = 300;

template<class ScalarType, class MV, class OP>
const int GmresPolySolMgr<ScalarType,MV,OP>::verbosity_default_ = Belos::Errors;

template<class ScalarType, class MV, class OP>
const int GmresPolySolMgr<ScalarType,MV,OP>::outputStyle_default_ = Belos::General;

template<class ScalarType, class MV, class OP>
const int GmresPolySolMgr<ScalarType,MV,OP>::outputFreq_default_ = -1;

template<class ScalarType, class MV, class OP>
const std::string GmresPolySolMgr<ScalarType,MV,OP>::impResScale_default_ = "Norm of RHS";

template<class ScalarType, class MV, class OP>
const std::string GmresPolySolMgr<ScalarType,MV,OP>::expResScale_default_ = "Norm of RHS";

template<class ScalarType, class MV, class OP>
const std::string GmresPolySolMgr<ScalarType,MV,OP>::label_default_ = "Belos";

template<class ScalarType, class MV, class OP>
const std::string GmresPolySolMgr<ScalarType,MV,OP>::orthoType_default_ = "DGKS";

template<class ScalarType, class MV, class OP>
const Teuchos::RCP<std::ostream>
GmresPolySolMgr<ScalarType,MV,OP>::outputStream_default_ = Teuchos::rcpFromRef (std::cout);


template<class ScalarType, class MV, class OP>
GmresPolySolMgr<ScalarType,MV,OP>::GmresPolySolMgr () :
  outputStream_ (outputStream_default_),
  polytol_ (polytol_default_),
  convtol_ (convtol_default_),
  orthoKappa_ (orthoKappa_default_),
  maxDegree_ (maxDegree_default_),
  maxRestarts_ (maxRestarts_default_),
  maxIters_ (maxIters_default_),
  numIters_ (0),
  blockSize_ (blockSize_default_),
  numBlocks_ (numBlocks_default_),
  verbosity_ (verbosity_default_),
  outputStyle_ (outputStyle_default_),
  outputFreq_ (outputFreq_default_),
  strictConvTol_ (strictConvTol_default_),
  showMaxResNormOnly_ (showMaxResNormOnly_default_),
  orthoType_ (orthoType_default_),
  impResScale_ (impResScale_default_),
  expResScale_ (expResScale_default_),
  poly_dim_ (0),
  label_ (label_default_),
  isPolyBuilt_ (false),
  isSet_ (false),
  isSTSet_ (false),
  expResTest_ (false),
  loaDetected_ (false)
{}


template<class ScalarType, class MV, class OP>
GmresPolySolMgr<ScalarType,MV,OP>::
GmresPolySolMgr (const Teuchos::RCP<LinearProblem<ScalarType,MV,OP> > &problem,
                 const Teuchos::RCP<Teuchos::ParameterList> &pl) :
  problem_ (problem),
  outputStream_ (outputStream_default_),
  polytol_ (polytol_default_),
  convtol_ (convtol_default_),
  orthoKappa_ (orthoKappa_default_),
  maxDegree_ (maxDegree_default_),
  maxRestarts_ (maxRestarts_default_),
  maxIters_ (maxIters_default_),
  numIters_ (0),
  blockSize_ (blockSize_default_),
  numBlocks_ (numBlocks_default_),
  verbosity_ (verbosity_default_),
  outputStyle_ (outputStyle_default_),
  outputFreq_ (outputFreq_default_),
  strictConvTol_ (strictConvTol_default_),
  showMaxResNormOnly_ (showMaxResNormOnly_default_),
  orthoType_ (orthoType_default_),
  impResScale_ (impResScale_default_),
  expResScale_ (expResScale_default_),
  poly_dim_ (0),
  label_ (label_default_),
  isPolyBuilt_ (false),
  isSet_ (false),
  isSTSet_ (false),
  expResTest_ (false),
  loaDetected_ (false)
{
  TEUCHOS_TEST_FOR_EXCEPTION(
    problem_.is_null (), std::invalid_argument,
    "Belos::GmresPolySolMgr: The given linear problem is null.  "
    "Please call this constructor with a nonnull LinearProblem argument, "
    "or call the constructor that does not take a LinearProblem.");

  // If the input parameter list is null, then the parameters take
  // default values.
  if (! pl.is_null ()) {
    setParameters (pl);
  }
}


template<class ScalarType, class MV, class OP>
Teuchos::RCP<const Teuchos::ParameterList>
GmresPolySolMgr<ScalarType,MV,OP>::getValidParameters() const
{
  if (validPL_.is_null ()) {
    Teuchos::RCP<Teuchos::ParameterList> pl = Teuchos::parameterList ();
    pl->set("Polynomial Tolerance", polytol_default_,
      "The relative residual tolerance that used to construct the GMRES polynomial.");
    pl->set("Maximum Degree", maxDegree_default_,
      "The maximum degree allowed for any GMRES polynomial.");
    pl->set("Convergence Tolerance", convtol_default_,
      "The relative residual tolerance that needs to be achieved by the\n"
      "iterative solver in order for the linear system to be declared converged." );
    pl->set("Maximum Restarts", maxRestarts_default_,
      "The maximum number of restarts allowed for each\n"
      "set of RHS solved.");
    pl->set("Maximum Iterations", maxIters_default_,
      "The maximum number of block iterations allowed for each\n"
      "set of RHS solved.");
    pl->set("Num Blocks", numBlocks_default_,
      "The maximum number of blocks allowed in the Krylov subspace\n"
      "for each set of RHS solved.");
    pl->set("Block Size", blockSize_default_,
      "The number of vectors in each block.  This number times the\n"
      "number of blocks is the total Krylov subspace dimension.");
    pl->set("Verbosity", verbosity_default_,
      "What type(s) of solver information should be outputted\n"
      "to the output stream.");
    pl->set("Output Style", outputStyle_default_,
      "What style is used for the solver information outputted\n"
      "to the output stream.");
    pl->set("Output Frequency", outputFreq_default_,
      "How often convergence information should be outputted\n"
      "to the output stream.");
    pl->set("Output Stream", outputStream_default_,
      "A reference-counted pointer to the output stream where all\n"
      "solver output is sent.");
    pl->set("Strict Convergence", strictConvTol_default_,
      "After polynomial is applied, whether solver should try to achieve\n"
      "the relative residual tolerance.");
    pl->set("Show Maximum Residual Norm Only", showMaxResNormOnly_default_,
      "When convergence information is printed, only show the maximum\n"
      "relative residual norm when the block size is greater than one.");
    pl->set("Implicit Residual Scaling", impResScale_default_,
      "The type of scaling used in the implicit residual convergence test.");
    pl->set("Explicit Residual Scaling", expResScale_default_,
      "The type of scaling used in the explicit residual convergence test.");
    pl->set("Timer Label", label_default_,
      "The string to use as a prefix for the timer labels.");
    //  pl->set("Restart Timers", restartTimers_);
    pl->set("Orthogonalization", orthoType_default_,
      "The type of orthogonalization to use: DGKS, ICGS, or IMGS.");
    pl->set("Orthogonalization Constant",orthoKappa_default_,
      "The constant used by DGKS orthogonalization to determine\n"
      "whether another step of classical Gram-Schmidt is necessary.");
    validPL_ = pl;
  }
  return validPL_;
}


template<class ScalarType, class MV, class OP>
void GmresPolySolMgr<ScalarType,MV,OP>::
setParameters (const Teuchos::RCP<Teuchos::ParameterList>& params)
{
  // Create the internal parameter list if ones doesn't already exist.
  if (params_.is_null ()) {
    params_ = Teuchos::parameterList (*getValidParameters ());
  }
  else {
    params->validateParameters (*getValidParameters ());
  }

  // Check for maximum polynomial degree
  if (params->isParameter("Maximum Degree")) {
    maxDegree_ = params->get("Maximum Degree",maxDegree_default_);

    // Update parameter in our list.
    params_->set("Maximum Degree", maxDegree_);
  }

  // Check for maximum number of restarts
  if (params->isParameter("Maximum Restarts")) {
    maxRestarts_ = params->get("Maximum Restarts",maxRestarts_default_);

    // Update parameter in our list.
    params_->set("Maximum Restarts", maxRestarts_);
  }

  // Check for maximum number of iterations
  if (params->isParameter("Maximum Iterations")) {
    maxIters_ = params->get("Maximum Iterations",maxIters_default_);

    // Update parameter in our list and in status test.
    params_->set("Maximum Iterations", maxIters_);
    if (maxIterTest_!=Teuchos::null)
      maxIterTest_->setMaxIters( maxIters_ );
  }

  // Check for blocksize
  if (params->isParameter("Block Size")) {
    blockSize_ = params->get("Block Size",blockSize_default_);
    TEUCHOS_TEST_FOR_EXCEPTION(blockSize_ <= 0, std::invalid_argument,
      "Belos::GmresPolySolMgr: \"Block Size\" must be strictly positive.");

    // Update parameter in our list.
    params_->set("Block Size", blockSize_);
  }

  // Check for the maximum number of blocks.
  if (params->isParameter("Num Blocks")) {
    numBlocks_ = params->get("Num Blocks",numBlocks_default_);
    TEUCHOS_TEST_FOR_EXCEPTION(numBlocks_ <= 0, std::invalid_argument,
      "Belos::GmresPolySolMgr: \"Num Blocks\" must be strictly positive.");

    // Update parameter in our list.
    params_->set("Num Blocks", numBlocks_);
  }

  // Check to see if the timer label changed.
  if (params->isParameter("Timer Label")) {
    std::string tempLabel = params->get("Timer Label", label_default_);

    // Update parameter in our list and solver timer
    if (tempLabel != label_) {
      label_ = tempLabel;
      params_->set("Timer Label", label_);
      std::string solveLabel = label_ + ": GmresPolySolMgr total solve time";
#ifdef BELOS_TEUCHOS_TIME_MONITOR
      timerSolve_ = Teuchos::TimeMonitor::getNewCounter(solveLabel);
#endif
      std::string polyLabel = label_ + ": GmresPolySolMgr polynomial creation time";
#ifdef BELOS_TEUCHOS_TIME_MONITOR
      timerPoly_ = Teuchos::TimeMonitor::getNewCounter(polyLabel);
#endif
      if (ortho_ != Teuchos::null) {
        ortho_->setLabel( label_ );
      }
    }
  }

  // Check if the orthogonalization changed.
  if (params->isParameter("Orthogonalization")) {
    std::string tempOrthoType = params->get("Orthogonalization",orthoType_default_);
    TEUCHOS_TEST_FOR_EXCEPTION( tempOrthoType != "DGKS" && tempOrthoType != "ICGS" && tempOrthoType != "IMGS",
                        std::invalid_argument,
                        "Belos::GmresPolySolMgr: \"Orthogonalization\" must be either \"DGKS\", \"ICGS\", or \"IMGS\".");
    if (tempOrthoType != orthoType_) {
      orthoType_ = tempOrthoType;
      // Create orthogonalization manager
      if (orthoType_=="DGKS") {
        if (orthoKappa_ <= 0) {
          ortho_ = Teuchos::rcp( new DGKSOrthoManager<ScalarType,MV,OP>( label_ ) );
        }
        else {
          ortho_ = Teuchos::rcp( new DGKSOrthoManager<ScalarType,MV,OP>( label_ ) );
          Teuchos::rcp_dynamic_cast<DGKSOrthoManager<ScalarType,MV,OP> >(ortho_)->setDepTol( orthoKappa_ );
        }
      }
      else if (orthoType_=="ICGS") {
        ortho_ = Teuchos::rcp( new ICGSOrthoManager<ScalarType,MV,OP>( label_ ) );
      }
      else if (orthoType_=="IMGS") {
        ortho_ = Teuchos::rcp( new IMGSOrthoManager<ScalarType,MV,OP>( label_ ) );
      }
    }
  }

  // Check which orthogonalization constant to use.
  if (params->isParameter("Orthogonalization Constant")) {
    orthoKappa_ = params->get("Orthogonalization Constant",orthoKappa_default_);

    // Update parameter in our list.
    params_->set("Orthogonalization Constant",orthoKappa_);
    if (orthoType_=="DGKS") {
      if (orthoKappa_ > 0 && ortho_ != Teuchos::null) {
        Teuchos::rcp_dynamic_cast<DGKSOrthoManager<ScalarType,MV,OP> >(ortho_)->setDepTol( orthoKappa_ );
      }
    }
  }

  // Check for a change in verbosity level
  if (params->isParameter("Verbosity")) {
    if (Teuchos::isParameterType<int>(*params,"Verbosity")) {
      verbosity_ = params->get("Verbosity", verbosity_default_);
    } else {
      verbosity_ = (int)Teuchos::getParameter<Belos::MsgType>(*params,"Verbosity");
    }

    // Update parameter in our list.
    params_->set("Verbosity", verbosity_);
    if (printer_ != Teuchos::null)
      printer_->setVerbosity(verbosity_);
  }

  // Check for a change in output style
  if (params->isParameter("Output Style")) {
    if (Teuchos::isParameterType<int>(*params,"Output Style")) {
      outputStyle_ = params->get("Output Style", outputStyle_default_);
    } else {
      outputStyle_ = (int)Teuchos::getParameter<Belos::OutputType>(*params,"Output Style");
    }

    // Reconstruct the convergence test if the explicit residual test is not being used.
    params_->set("Output Style", outputStyle_);
    if (outputTest_ != Teuchos::null) {
      isSTSet_ = false;
    }
  }

  // output stream
  if (params->isParameter("Output Stream")) {
    outputStream_ = Teuchos::getParameter<Teuchos::RCP<std::ostream> >(*params,"Output Stream");

    // Update parameter in our list.
    params_->set("Output Stream", outputStream_);
    if (printer_ != Teuchos::null)
      printer_->setOStream( outputStream_ );
  }

  // frequency level
  if (verbosity_ & Belos::StatusTestDetails) {
    if (params->isParameter("Output Frequency")) {
      outputFreq_ = params->get("Output Frequency", outputFreq_default_);
    }

    // Update parameter in out list and output status test.
    params_->set("Output Frequency", outputFreq_);
    if (outputTest_ != Teuchos::null)
      outputTest_->setOutputFrequency( outputFreq_ );
  }

  // Create output manager if we need to.
  if (printer_ == Teuchos::null) {
    printer_ = Teuchos::rcp( new OutputManager<ScalarType>(verbosity_, outputStream_) );
  }

  // Convergence
  //typedef Belos::StatusTestCombo<ScalarType,MV,OP>  StatusTestCombo_t; // unused
  //typedef Belos::StatusTestGenResNorm<ScalarType,MV,OP>  StatusTestResNorm_t; // unused

  // Check for polynomial convergence tolerance
  if (params->isParameter("Polynomial Tolerance")) {
    polytol_ = params->get("Polynomial Tolerance",polytol_default_);

    // Update parameter in our list and residual tests.
    params_->set("Polynomial Tolerance", polytol_);
  }

  // Check for convergence tolerance
  if (params->isParameter("Convergence Tolerance")) {
    convtol_ = params->get("Convergence Tolerance",convtol_default_);

    // Update parameter in our list and residual tests.
    params_->set("Convergence Tolerance", convtol_);
    if (impConvTest_ != Teuchos::null)
      impConvTest_->setTolerance( convtol_ );
    if (expConvTest_ != Teuchos::null)
      expConvTest_->setTolerance( convtol_ );
  }

  // Check if user requires solver to reach convergence tolerance
  if (params->isParameter("Strict Convergence")) {
    strictConvTol_ = params->get("Strict Convergence",strictConvTol_default_);

    // Update parameter in our list and residual tests
    params_->set("Strict Convergence", strictConvTol_);
  }

  // Check for a change in scaling, if so we need to build new residual tests.
  if (params->isParameter("Implicit Residual Scaling")) {
    std::string tempImpResScale = Teuchos::getParameter<std::string>( *params, "Implicit Residual Scaling" );

    // Only update the scaling if it's different.
    if (impResScale_ != tempImpResScale) {
      Belos::ScaleType impResScaleType = convertStringToScaleType( tempImpResScale );
      impResScale_ = tempImpResScale;

      // Update parameter in our list and residual tests
      params_->set("Implicit Residual Scaling", impResScale_);
      if (impConvTest_ != Teuchos::null) {
        try {
          impConvTest_->defineScaleForm( impResScaleType, Belos::TwoNorm );
        }
        catch (std::exception& e) {
          // Make sure the convergence test gets constructed again.
          isSTSet_ = false;
        }
      }
    }
  }

  if (params->isParameter("Explicit Residual Scaling")) {
    std::string tempExpResScale = Teuchos::getParameter<std::string>( *params, "Explicit Residual Scaling" );

    // Only update the scaling if it's different.
    if (expResScale_ != tempExpResScale) {
      Belos::ScaleType expResScaleType = convertStringToScaleType( tempExpResScale );
      expResScale_ = tempExpResScale;

      // Update parameter in our list and residual tests
      params_->set("Explicit Residual Scaling", expResScale_);
      if (expConvTest_ != Teuchos::null) {
        try {
          expConvTest_->defineScaleForm( expResScaleType, Belos::TwoNorm );
        }
        catch (std::exception& e) {
          // Make sure the convergence test gets constructed again.
          isSTSet_ = false;
        }
      }
    }
  }


  if (params->isParameter("Show Maximum Residual Norm Only")) {
    showMaxResNormOnly_ = Teuchos::getParameter<bool>(*params,"Show Maximum Residual Norm Only");

    // Update parameter in our list and residual tests
    params_->set("Show Maximum Residual Norm Only", showMaxResNormOnly_);
    if (impConvTest_ != Teuchos::null)
      impConvTest_->setShowMaxResNormOnly( showMaxResNormOnly_ );
    if (expConvTest_ != Teuchos::null)
      expConvTest_->setShowMaxResNormOnly( showMaxResNormOnly_ );
  }

  // Create orthogonalization manager if we need to.
  if (ortho_ == Teuchos::null) {
    if (orthoType_=="DGKS") {
      if (orthoKappa_ <= 0) {
        ortho_ = Teuchos::rcp( new DGKSOrthoManager<ScalarType,MV,OP>( label_ ) );
      }
      else {
        ortho_ = Teuchos::rcp( new DGKSOrthoManager<ScalarType,MV,OP>( label_ ) );
        Teuchos::rcp_dynamic_cast<DGKSOrthoManager<ScalarType,MV,OP> >(ortho_)->setDepTol( orthoKappa_ );
      }
    }
    else if (orthoType_=="ICGS") {
      ortho_ = Teuchos::rcp( new ICGSOrthoManager<ScalarType,MV,OP>( label_ ) );
    }
    else if (orthoType_=="IMGS") {
      ortho_ = Teuchos::rcp( new IMGSOrthoManager<ScalarType,MV,OP>( label_ ) );
    }
    else {
      TEUCHOS_TEST_FOR_EXCEPTION(orthoType_!="ICGS"&&orthoType_!="DGKS"&&orthoType_!="IMGS",std::logic_error,
        "Belos::GmresPolySolMgr(): Invalid orthogonalization type.");
    }
  }

  // Create the timers if we need to.
  if (timerSolve_ == Teuchos::null) {
    std::string solveLabel = label_ + ": GmresPolySolMgr total solve time";
#ifdef BELOS_TEUCHOS_TIME_MONITOR
    timerSolve_ = Teuchos::TimeMonitor::getNewCounter(solveLabel);
#endif
  }

  if (timerPoly_ == Teuchos::null) {
    std::string polyLabel = label_ + ": GmresPolySolMgr polynomial creation time";
#ifdef BELOS_TEUCHOS_TIME_MONITOR
    timerPoly_ = Teuchos::TimeMonitor::getNewCounter(polyLabel);
#endif
  }

  // Inform the solver manager that the current parameters were set.
  isSet_ = true;
}

// Check the status test versus the defined linear problem
template<class ScalarType, class MV, class OP>
bool GmresPolySolMgr<ScalarType,MV,OP>::checkStatusTest() {

  typedef Belos::StatusTestCombo<ScalarType,MV,OP>  StatusTestCombo_t;
  typedef Belos::StatusTestGenResNorm<ScalarType,MV,OP>  StatusTestGenResNorm_t;
  typedef Belos::StatusTestImpResNorm<ScalarType,MV,OP>  StatusTestImpResNorm_t;

  // Basic test checks maximum iterations and native residual.
  maxIterTest_ = Teuchos::rcp( new StatusTestMaxIters<ScalarType,MV,OP>( maxIters_ ) );

  // If there is a left preconditioner, we create a combined status test that checks the implicit
  // and then explicit residual norm to see if we have convergence.
  if (!Teuchos::is_null(problem_->getLeftPrec())) {
    expResTest_ = true;
  }

  if (expResTest_) {

    // Implicit residual test, using the native residual to determine if convergence was achieved.
    Teuchos::RCP<StatusTestGenResNorm_t> tmpImpConvTest =
      Teuchos::rcp( new StatusTestGenResNorm_t( convtol_ ) );
    tmpImpConvTest->defineScaleForm( convertStringToScaleType(impResScale_), Belos::TwoNorm );
    tmpImpConvTest->setShowMaxResNormOnly( showMaxResNormOnly_ );
    impConvTest_ = tmpImpConvTest;

    // Explicit residual test once the native residual is below the tolerance
    Teuchos::RCP<StatusTestGenResNorm_t> tmpExpConvTest =
      Teuchos::rcp( new StatusTestGenResNorm_t( convtol_ ) );
    tmpExpConvTest->defineResForm( StatusTestGenResNorm_t::Explicit, Belos::TwoNorm );
    tmpExpConvTest->defineScaleForm( convertStringToScaleType(expResScale_), Belos::TwoNorm );
    tmpExpConvTest->setShowMaxResNormOnly( showMaxResNormOnly_ );
    expConvTest_ = tmpExpConvTest;

    // The convergence test is a combination of the "cheap" implicit test and explicit test.
    convTest_ = Teuchos::rcp( new StatusTestCombo_t( StatusTestCombo_t::SEQ, impConvTest_, expConvTest_ ) );
  }
  else {

    // Implicit residual test, using the native residual to determine if convergence was achieved.
    // Use test that checks for loss of accuracy.
    Teuchos::RCP<StatusTestImpResNorm_t> tmpImpConvTest =
      Teuchos::rcp( new StatusTestImpResNorm_t( convtol_ ) );
    tmpImpConvTest->defineScaleForm( convertStringToScaleType(impResScale_), Belos::TwoNorm );
    tmpImpConvTest->setShowMaxResNormOnly( showMaxResNormOnly_ );
    impConvTest_ = tmpImpConvTest;

    // Set the explicit and total convergence test to this implicit test that checks for accuracy loss.
    expConvTest_ = impConvTest_;
    convTest_ = impConvTest_;
  }

  sTest_ = Teuchos::rcp( new StatusTestCombo_t( StatusTestCombo_t::OR, maxIterTest_, convTest_ ) );

  // Create the status test output class.
  // This class manages and formats the output from the status test.
  StatusTestOutputFactory<ScalarType,MV,OP> stoFactory( outputStyle_ );
  outputTest_ = stoFactory.create( printer_, sTest_, outputFreq_, Passed+Failed+Undefined );

  // Set the solver string for the output test
  std::string solverDesc = " Gmres Polynomial ";
  outputTest_->setSolverDesc( solverDesc );


  // The status test is now set.
  isSTSet_ = true;

  return false;
}

template<class ScalarType, class MV, class OP>
bool GmresPolySolMgr<ScalarType,MV,OP>::generatePoly()
{
  // Create a copy of the linear problem that has a zero initial guess and random RHS.
  Teuchos::RCP<MV> newX  = MVT::Clone( *(problem_->getLHS()), 1 );
  Teuchos::RCP<MV> newB  = MVT::Clone( *(problem_->getRHS()), 1 );
  MVT::MvInit( *newX, STS::zero() );
  MVT::MvRandom( *newB );
  Teuchos::RCP<LinearProblem<ScalarType,MV,OP> > newProblem =
    Teuchos::rcp( new LinearProblem<ScalarType,MV,OP>( problem_->getOperator(), newX, newB ) );
  newProblem->setLeftPrec( problem_->getLeftPrec() );
  newProblem->setRightPrec( problem_->getRightPrec() );
  newProblem->setLabel("Belos GMRES Poly Generation");
  newProblem->setProblem();
  std::vector<int> idx(1,0);       // Must set the index to be the first vector (0)!
  newProblem->setLSIndex( idx );

  // Create a parameter list for the GMRES iteration.
  Teuchos::ParameterList polyList;

  // Tell the block solver that the block size is one.
  polyList.set("Num Blocks",maxDegree_);
  polyList.set("Block Size",1);
  polyList.set("Keep Hessenberg", true);

  // Create a simple status test that either reaches the relative residual tolerance or maximum polynomial size.
  Teuchos::RCP<StatusTestMaxIters<ScalarType,MV,OP> > maxItrTst =
    Teuchos::rcp( new StatusTestMaxIters<ScalarType,MV,OP>( maxDegree_ ) );

  // Implicit residual test, using the native residual to determine if convergence was achieved.
  Teuchos::RCP<StatusTestGenResNorm<ScalarType,MV,OP> > convTst =
    Teuchos::rcp( new StatusTestGenResNorm<ScalarType,MV,OP>( polytol_ ) );
  convTst->defineScaleForm( convertStringToScaleType(impResScale_), Belos::TwoNorm );

  // Convergence test that stops the iteration when either are satisfied.
  Teuchos::RCP<StatusTestCombo<ScalarType,MV,OP> > polyTest =
    Teuchos::rcp( new StatusTestCombo<ScalarType,MV,OP>( StatusTestCombo<ScalarType,MV,OP>::OR, maxItrTst, convTst ) );

  // Create Gmres iteration object to perform one cycle of Gmres.
  Teuchos::RCP<BlockGmresIter<ScalarType,MV,OP> > gmres_iter;
  gmres_iter = Teuchos::rcp( new BlockGmresIter<ScalarType,MV,OP>(newProblem,printer_,polyTest,ortho_,polyList) );

  // Create the first block in the current Krylov basis (residual).
  Teuchos::RCP<MV> V_0 = MVT::Clone( *(newProblem->getRHS()), 1 );
  newProblem->computeCurrPrecResVec( &*V_0 );

  // Get a matrix to hold the orthonormalization coefficients.
  poly_r0_ = Teuchos::rcp( new Teuchos::SerialDenseVector<int,ScalarType>(1) );

  // Orthonormalize the new V_0
  int rank = ortho_->normalize( *V_0, poly_r0_ );
  TEUCHOS_TEST_FOR_EXCEPTION(rank != 1,GmresPolySolMgrOrthoFailure,
    "Belos::GmresPolySolMgr::generatePoly(): Failed to compute initial block of orthonormal vectors for polynomial generation.");

  // Set the new state and initialize the solver.
  GmresIterationState<ScalarType,MV> newstate;
  newstate.V = V_0;
  newstate.z = poly_r0_;
  newstate.curDim = 0;
  gmres_iter->initializeGmres(newstate);

  // Perform Gmres iteration
  bool polyConverged = false;
  try {
    gmres_iter->iterate();

    // Check convergence first
    if ( convTst->getStatus() == Passed ) {
      // we have convergence
      polyConverged = true;
    }
  }
  catch (GmresIterationOrthoFailure e) {
    // Try to recover the most recent least-squares solution
    gmres_iter->updateLSQR( gmres_iter->getCurSubspaceDim() );

    // Check to see if the most recent least-squares solution yielded convergence.
    polyTest->checkStatus( &*gmres_iter );
    if (convTst->getStatus() == Passed)
      polyConverged = true;
    }
    catch (std::exception e) {
    printer_->stream(Errors) << "Error! Caught exception in BlockGmresIter::iterate() at iteration "
                             << gmres_iter->getNumIters() << std::endl
                             << e.what() << std::endl;
    throw;
  }

  // FIXME (mfh 27 Apr 2013) Why aren't we using polyConverged after
  // setting it?  I'm tired of the compile warning so I'll silence it
  // here, but I'm curious why we aren't using the variable.
  (void) polyConverged;

  // Get the solution for this polynomial, use in comparison below
  Teuchos::RCP<MV> currX = gmres_iter->getCurrentUpdate();

  // Record polynomial info, get current GMRES state
  GmresIterationState<ScalarType,MV> gmresState = gmres_iter->getState();

  // If the polynomial has no dimension, the tolerance is too low, return false
  poly_dim_ = gmresState.curDim;
  if (poly_dim_ == 0) {
    return false;
  }
  //
  //  Make a view and then copy the RHS of the least squares problem.
  //
  poly_y_ = Teuchos::rcp( new Teuchos::SerialDenseMatrix<int,ScalarType>( Teuchos::Copy, *gmresState.z, poly_dim_, 1 ) );
  poly_H_ = Teuchos::rcp( new Teuchos::SerialDenseMatrix<int,ScalarType>( *gmresState.H ) );
  //
  // Solve the least squares problem.
  //
  const ScalarType one = STS::one ();
  Teuchos::BLAS<int,ScalarType> blas;
  blas.TRSM( Teuchos::LEFT_SIDE, Teuchos::UPPER_TRI, Teuchos::NO_TRANS,
             Teuchos::NON_UNIT_DIAG, poly_dim_, 1, one,
             gmresState.R->values(), gmresState.R->stride(),
             poly_y_->values(), poly_y_->stride() );
  //
  // Generate the polynomial operator
  //
  poly_Op_ = Teuchos::rcp(
               new Belos::GmresPolyOp<ScalarType,MV,OP>( problem_, poly_H_, poly_y_, poly_r0_ ) );

  return true;
}


template<class ScalarType, class MV, class OP>
ReturnType GmresPolySolMgr<ScalarType,MV,OP>::solve ()
{
  using Teuchos::RCP;
  using Teuchos::rcp;
  typedef Teuchos::SerialDenseMatrix<int, ScalarType> SDM;

  // Set the current parameters if they were not set before.  NOTE:
  // This may occur if the user generated the solver manager with the
  // default constructor and then didn't set any parameters using
  // setParameters().
  if (! isSet_) {
    setParameters (Teuchos::parameterList (*getValidParameters ()));
  }

  TEUCHOS_TEST_FOR_EXCEPTION(
    problem_.is_null (), GmresPolySolMgrLinearProblemFailure,
    "Belos::GmresPolySolMgr::solve: The linear problem has not been set yet, "
    "or was set to null.  Please call setProblem() with a nonnull input before "
    "calling solve().");

  TEUCHOS_TEST_FOR_EXCEPTION(
    ! problem_->isProblemSet (), GmresPolySolMgrLinearProblemFailure,
    "Belos::GmresPolySolMgr::solve: The linear problem is not ready.  Please "
    "call setProblem() on the LinearProblem object before calling solve().");

  if (! isSTSet_ || (! expResTest_ && ! problem_->getLeftPrec ().is_null ())) {
    // checkStatusTest() shouldn't have side effects, but it's still
    // not such a good idea to put possibly side-effect-y function
    // calls in a macro invocation.  It could be expensive if the
    // macro evaluates the argument more than once, for example.
    const bool check = checkStatusTest ();
    TEUCHOS_TEST_FOR_EXCEPTION(
      check, GmresPolySolMgrLinearProblemFailure,
      "Belos::GmresPolySolMgr::solve: Linear problem and requested status "
      "tests are incompatible.");
  }

  // If the GMRES polynomial has not been constructed for this
  // (nmatrix, preconditioner) pair, generate it.
  if (! isPolyBuilt_) {
#ifdef BELOS_TEUCHOS_TIME_MONITOR
    Teuchos::TimeMonitor slvtimer(*timerPoly_);
#endif
    isPolyBuilt_ = generatePoly();
    TEUCHOS_TEST_FOR_EXCEPTION( !isPolyBuilt_ && poly_dim_==0, GmresPolySolMgrPolynomialFailure,
      "Belos::GmresPolySolMgr::generatePoly(): Failed to generate a non-trivial polynomial, reduce polynomial tolerance.");
    TEUCHOS_TEST_FOR_EXCEPTION( !isPolyBuilt_, GmresPolySolMgrPolynomialFailure,
      "Belos::GmresPolySolMgr::generatePoly(): Failed to generate polynomial that satisfied requirements.");
  }

  // Assume convergence is achieved if user does not require strict convergence.
  bool isConverged = true;

  // Solve the linear system using the polynomial
  {
#ifdef BELOS_TEUCHOS_TIME_MONITOR
    Teuchos::TimeMonitor slvtimer(*timerSolve_);
#endif

    // Apply the polynomial to the current linear system
    poly_Op_->Apply( *problem_->getRHS(), *problem_->getLHS() );

    // Reset the problem to acknowledge the updated solution
    problem_->setProblem ();

    // If we have to strictly adhere to the requested convergence tolerance, set up a standard GMRES solver.
    if (strictConvTol_) {

      // Create indices for the linear systems to be solved.
      int startPtr = 0;
      int numRHS2Solve = MVT::GetNumberVecs( *(problem_->getRHS()) );
      int numCurrRHS = ( numRHS2Solve < blockSize_) ? numRHS2Solve : blockSize_;


      // If an adaptive block size is allowed then only the linear
      // systems that need to be solved are solved.  Otherwise, the
      // index set is generated that informs the linear problem that
      // some linear systems are augmented.

      std::vector<int> currIdx (blockSize_);
      for (int i = 0; i < numCurrRHS; ++i) {
        currIdx[i] = startPtr+i;
      }
      for (int i = numCurrRHS; i < blockSize_; ++i) {
        currIdx[i] = -1;
      }

      // Inform the linear problem of the current linear system to solve.
      problem_->setLSIndex (currIdx);

      //////////////////////////////////////////////////////////////////////////////////////
      // Parameter list
      Teuchos::ParameterList plist;
      plist.set ("Block Size", blockSize_);

      ptrdiff_t dim = MVT::GetGlobalLength( *(problem_->getRHS()) );
      if (blockSize_*static_cast<ptrdiff_t>(numBlocks_) > dim) {
        ptrdiff_t tmpNumBlocks = 0;
        if (blockSize_ == 1) {
          tmpNumBlocks = dim / blockSize_;  // Allow for a good breakdown.
        } else {
          tmpNumBlocks = ( dim - blockSize_) / blockSize_;  // Allow for restarting.
        }
        printer_->stream(Warnings)
          << "Warning! Requested Krylov subspace dimension is larger than "
          << "operator dimension!" << std::endl << "The maximum number of "
          << "blocks allowed for the Krylov subspace will be adjusted to "
          << tmpNumBlocks << std::endl;
        plist.set ("Num Blocks", Teuchos::asSafe<int> (tmpNumBlocks));
      }
      else {
        plist.set ("Num Blocks", numBlocks_);
      }

      // Reset the status test.
      outputTest_->reset ();
      loaDetected_ = false;

      // Assume convergence is achieved, then let any failed
      // convergence set this to false.
      isConverged = true;

      //
      // Solve using BlockGmres
      //

      RCP<GmresIteration<ScalarType,MV,OP> > block_gmres_iter =
        rcp (new BlockGmresIter<ScalarType,MV,OP> (problem_, printer_,
                                                   outputTest_, ortho_, plist));

      // Enter solve() iterations
      while (numRHS2Solve > 0) {
        // Set the current number of blocks and block size with the
        // Gmres iteration.
        if (blockSize_*numBlocks_ > dim) {
          int tmpNumBlocks = 0;
          if (blockSize_ == 1) {
            // Leave space for happy breakdown.
            tmpNumBlocks = dim / blockSize_;
          } else {
            // Leave space for restarting.
            tmpNumBlocks = (dim - blockSize_) / blockSize_;
          }
          block_gmres_iter->setSize (blockSize_, tmpNumBlocks);
        }
        else {
          block_gmres_iter->setSize (blockSize_, numBlocks_);
        }

        // Reset the number of iterations.
        block_gmres_iter->resetNumIters ();

        // Reset the number of calls that the status test output knows about.
        outputTest_->resetNumCalls ();

        // Create the first block in the current Krylov basis.
        RCP<MV> V_0 = MVT::CloneCopy (*(problem_->getInitPrecResVec ()), currIdx);

        // Get a matrix to hold the orthonormalization coefficients.
        RCP<SDM> z_0 = rcp (new SDM (blockSize_, blockSize_));

        // Orthonormalize the new V_0
        int rank = ortho_->normalize (*V_0, z_0);
        TEUCHOS_TEST_FOR_EXCEPTION(
          rank != blockSize_, GmresPolySolMgrOrthoFailure,
          "Belos::GmresPolySolMgr::solve: Failed to compute initial block of "
          "orthonormal vectors.");

        // Set the new state and initialize the solver.
        GmresIterationState<ScalarType,MV> newstate;
        newstate.V = V_0;
        newstate.z = z_0;
        newstate.curDim = 0;
        block_gmres_iter->initializeGmres(newstate);
        int numRestarts = 0;

        while(1) {
          try {
            block_gmres_iter->iterate();

            // check convergence first
            if ( convTest_->getStatus() == Passed ) {
              if ( expConvTest_->getLOADetected() ) {
              // we don't have convergence
                loaDetected_ = true;
                isConverged = false;
              }
              break;  // break from while(1){block_gmres_iter->iterate()}
            }

            // check for maximum iterations
            else if ( maxIterTest_->getStatus() == Passed ) {
              // we don't have convergence
              isConverged = false;
              break;  // break from while(1){block_gmres_iter->iterate()}
            }
            // check for restarting, i.e. the subspace is full
            else if (block_gmres_iter->getCurSubspaceDim () ==
                     block_gmres_iter->getMaxSubspaceDim ()) {
              if (numRestarts >= maxRestarts_) {
                isConverged = false;
                break; // break from while(1){block_gmres_iter->iterate()}
              }
              numRestarts++;

              printer_->stream(Debug)
                << " Performing restart number " << numRestarts << " of "
                << maxRestarts_ << std::endl << std::endl;

              // Update the linear problem.
              RCP<MV> update = block_gmres_iter->getCurrentUpdate();
              problem_->updateSolution (update, true);

              // Get the state.
              GmresIterationState<ScalarType,MV> oldState = block_gmres_iter->getState();

              // Compute the restart vector.
              // Get a view of the current Krylov basis.
              //
              // We call this VV_0 to avoid shadowing the previously
              // defined V_0 above.
              RCP<MV> VV_0  = MVT::Clone (*(oldState.V), blockSize_);
              problem_->computeCurrPrecResVec (&*VV_0);

              // Get a view of the first block of the Krylov basis.
              //
              // We call this zz_0 to avoid shadowing the previously
              // defined z_0 above.
              RCP<SDM> zz_0 = rcp (new SDM (blockSize_, blockSize_));

              // Orthonormalize the new VV_0
              const int theRank = ortho_->normalize( *VV_0, zz_0 );
              TEUCHOS_TEST_FOR_EXCEPTION(
                theRank != blockSize_, GmresPolySolMgrOrthoFailure,
                "Belos::GmresPolySolMgr::solve: Failed to compute initial "
                "block of orthonormal vectors after restart.");

              // Set the new state and initialize the solver.
              GmresIterationState<ScalarType,MV> theNewState;
              theNewState.V = VV_0;
              theNewState.z = zz_0;
              theNewState.curDim = 0;
              block_gmres_iter->initializeGmres (theNewState);
            } // end of restarting
            //
            // We returned from iterate(), but none of our status
            // tests Passed.  Something is wrong, and it is probably
            // our fault.
            //
            else {
              TEUCHOS_TEST_FOR_EXCEPTION(
                true, std::logic_error,
                "Belos::GmresPolySolMgr::solve: Invalid return from "
                "BlockGmresIter::iterate().  Please report this bug "
                "to the Belos developers.");
            }
          }
          catch (const GmresIterationOrthoFailure& e) {
            // If the block size is not one, it's not considered a lucky breakdown.
            if (blockSize_ != 1) {
              printer_->stream(Errors)
                << "Error! Caught std::exception in BlockGmresIter::iterate() "
                << "at iteration " << block_gmres_iter->getNumIters()
                << std::endl << e.what() << std::endl;
              if (convTest_->getStatus() != Passed) {
                isConverged = false;
              }
              break;
            }
            else {
              // If the block size is one, try to recover the most
              // recent least-squares solution
              block_gmres_iter->updateLSQR (block_gmres_iter->getCurSubspaceDim ());

              // Check to see if the most recent least-squares
              // solution yielded convergence.
              sTest_->checkStatus (&*block_gmres_iter);
              if (convTest_->getStatus() != Passed) {
                isConverged = false;
              }
              break;
            }
          }
          catch (const std::exception &e) {
            printer_->stream(Errors)
              << "Error! Caught std::exception in BlockGmresIter::iterate() "
              << "at iteration " << block_gmres_iter->getNumIters() << std::endl
              << e.what() << std::endl;
            throw;
          }
        }

        // Compute the current solution.  Update the linear problem.
        // Attempt to get the current solution from the residual
        // status test, if it has one.
        if (! Teuchos::is_null (expConvTest_->getSolution ()) ) {
          RCP<MV> newX = expConvTest_->getSolution ();
          RCP<MV> curX = problem_->getCurrLHSVec ();
          MVT::MvAddMv (STS::zero (), *newX, STS::one (), *newX, *curX);
        }
        else {
          RCP<MV> update = block_gmres_iter->getCurrentUpdate ();
          problem_->updateSolution (update, true);
        }

        // Inform the linear problem that we are finished with this block linear system.
        problem_->setCurrLS ();

        // Update indices for the linear systems to be solved.
        startPtr += numCurrRHS;
        numRHS2Solve -= numCurrRHS;
        if (numRHS2Solve > 0) {
          numCurrRHS = (numRHS2Solve < blockSize_) ? numRHS2Solve : blockSize_;

          currIdx.resize (blockSize_);
          for (int i=0; i<numCurrRHS; ++i) {
            currIdx[i] = startPtr+i;
          }
          for (int i=numCurrRHS; i<blockSize_; ++i) {
            currIdx[i] = -1;
          }

          // Set the next indices.
          problem_->setLSIndex( currIdx );
        }
        else {
          currIdx.resize( numRHS2Solve );
        }

      }// while ( numRHS2Solve > 0 )

      // print final summary
      sTest_->print( printer_->stream(FinalSummary) );

    } // if (strictConvTol_)
  } // timing block

  // print timing information
#ifdef BELOS_TEUCHOS_TIME_MONITOR
  // Calling summarize() can be expensive, so don't call unless the
  // user wants to print out timing details.  summarize() will do all
  // the work even if it's passed a "black hole" output stream.
  if (verbosity_ & TimingDetails)
    Teuchos::TimeMonitor::summarize( printer_->stream(TimingDetails) );
#endif

  if (!isConverged || loaDetected_) {
    return Unconverged; // return from GmresPolySolMgr::solve()
  }
  return Converged; // return from GmresPolySolMgr::solve()
}


template<class ScalarType, class MV, class OP>
std::string GmresPolySolMgr<ScalarType,MV,OP>::description () const
{
  std::ostringstream out;

  out << "\"Belos::GmresPolySolMgr\": {"
      << "ScalarType: " << Teuchos::TypeNameTraits<ScalarType>::name ()
      << ", Ortho Type: " << orthoType_
      << ", Block Size: " << blockSize_
      << ", Num Blocks: " << numBlocks_
      << ", Max Restarts: " << maxRestarts_;
  out << "}";
  return out.str ();
}

} // namespace Belos

#endif // BELOS_GMRES_POLY_SOLMGR_HPP
libtrilinos-belos-dev 12.4.2-2 / usr / include / trilinos / BelosGmresPolySolMgr.hpp
