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Belos::BlockGCRODRSolMgr< ScalarType, MV, OP > Class Template Reference

A solver manager for the Block GCRO-DR (Block Recycling GMRES) linear solver. More...

#include <BelosBlockGCRODRSolMgr.hpp>

Inheritance diagram for Belos::BlockGCRODRSolMgr< ScalarType, MV, OP >:
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List of all members.

Public Member Functions

Constructors/Destructor
 BlockGCRODRSolMgr ()
 Default constructor.
 BlockGCRODRSolMgr (const Teuchos::RCP< LinearProblem< ScalarType, MV, OP > > &problem, const Teuchos::RCP< Teuchos::ParameterList > &pl)
 Basic constructor for GCRODRSolMgr.
virtual ~BlockGCRODRSolMgr ()
 Destructor.
Implementation of the Teuchos::Describable interface
std::string description () const
 A description of the Block GCRODR solver manager.
Accessor methods
const LinearProblem
< ScalarType, MV, OP > & 
getProblem () const
 Get current linear problem being solved for in this object.
Teuchos::RCP< const
Teuchos::ParameterList
getValidParameters () const
 Get a parameter list containing the valid parameters for this object.
Teuchos::RCP< const
Teuchos::ParameterList
getCurrentParameters () const
 Get a parameter list containing the current parameters for this object.
int getNumIters () const
 Get the iteration count for the most recent call to solve().
bool isLOADetected () const
 Whether a loss of accuracy was detected during the most recent solve.
Set methods
void setProblem (const Teuchos::RCP< LinearProblem< ScalarType, MV, OP > > &problem)
 Set the linear problem to solve on the next call to solve().
void setParameters (const Teuchos::RCP< Teuchos::ParameterList > &params)
 Set the parameters the solver should use to solve the linear problem.
Reset methods
void reset (const ResetType type)
 Performs a reset of the solver manager specified by the ResetType.

Solver application methods

ReturnType solve ()
 Solve the current linear problem.

Detailed Description

template<class ScalarType, class MV, class OP>
class Belos::BlockGCRODRSolMgr< ScalarType, MV, OP >

A solver manager for the Block GCRO-DR (Block Recycling GMRES) linear solver.

Author:
Kirk M. Soodhalter and Michael Parks

GCRO-DR (also called Recycling GMRES) is a variant of GMRES that can more efficiently solve sequences of closely related linear systems. It does so by "recycling" Krylov basis information from previous solves.

The original GCRO-DR algorithm can only solve one right-hand side at a time. Block GCRO-DR extends GCRO-DR so that it can solve multiple right-hand sides at a time; thus, it can solve sequences of block systems.

Definition at line 142 of file BelosBlockGCRODRSolMgr.hpp.


Constructor & Destructor Documentation

template<class ScalarType , class MV , class OP >
Belos::BlockGCRODRSolMgr< ScalarType, MV, OP >::BlockGCRODRSolMgr ( )

Default constructor.

This constructor sets up the solver with default parameters. You must call the solver's setProblem() with a valid linear problem to solve, before you can call its solve() method. You may change the solver's parameters from their default values by calling setParameters().

Definition at line 528 of file BelosBlockGCRODRSolMgr.hpp.

template<class ScalarType , class MV , class OP >
Belos::BlockGCRODRSolMgr< ScalarType, MV, OP >::BlockGCRODRSolMgr ( const Teuchos::RCP< LinearProblem< ScalarType, MV, OP > > &  problem,
const Teuchos::RCP< Teuchos::ParameterList > &  pl 
)

Basic constructor for GCRODRSolMgr.

This constructor accepts the LinearProblem to be solved in addition to a parameter list of options for the solver manager. Some of the more important options include the following:

  • "Num Blocks": an int specifying the number of blocks allocated for the Krylov basis. Default: 50.
  • "Block Size": an int specifying the number of right hand sides being solved at a time.
  • "Num Recycled Blocks": an int specifying the number of blocks allocated for the Krylov basis. Default: 5.
  • "Maximum Iterations": an int specifying the maximum number of iterations the underlying solver is allowed to perform. Default: 5000.
  • "Maximum Restarts": an int specifying the maximum number of restarts the underlying solver is allowed to perform. Default: 100.
  • "Orthogonalization": an std::string specifying the desired orthogonalization. Currently supported values: "DGKS", "ICGS", "IMGS", and "TSQR" (if Belos was built with TSQR support). Default: "DGKS".
  • "Orthogonalization Parameters": a ParameterList or RCP<(const) ParameterList> of parameters specific to the type of orthogonalization used. Defaults are set automatically.
  • "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 MagnitudeType specifying the level that residual norms must reach to decide convergence. Default: 1e-8.

Other supported options:

  • "Output Frequency": an int specifying how often (in terms of number of iterations) convergence information should be output to the output stream. Default: -1 (means never output convergence information).
  • "Output Stream": a reference-counted pointer to the output stream where all solver output is sent. Default stream is std::cout (stdout, in C terms). For stderr, supply Teuchos::rcp(&std::cerr, false).
  • "Implicit Residual Scaling": the type of scaling used in the implicit residual convergence test. Default: "Norm of Preconditioned Initial Residual".
  • "Explicit Residual Scaling": the type of scaling used in the explicit residual convergence test. Default: "Norm of Initial Residual".
  • "Timer Label": the string to use as a prefix for the timer labels. Default: "Belos"
  • "Orthogonalization Constant": a MagnitudeType corresponding to the "depTol" parameter of DGKS orthogonalization. Ignored unless DGKS orthogonalization is used. DGKS decides the default value.

Definition at line 535 of file BelosBlockGCRODRSolMgr.hpp.

template<class ScalarType , class MV , class OP >
virtual Belos::BlockGCRODRSolMgr< ScalarType, MV, OP >::~BlockGCRODRSolMgr ( ) [inline, virtual]

Destructor.

Definition at line 226 of file BelosBlockGCRODRSolMgr.hpp.


Member Function Documentation

template<class ScalarType , class MV , class OP >
std::string Belos::BlockGCRODRSolMgr< ScalarType, MV, OP >::description ( ) const [virtual]

A description of the Block GCRODR solver manager.

Reimplemented from Teuchos::Describable.

Definition at line 643 of file BelosBlockGCRODRSolMgr.hpp.

template<class ScalarType , class MV , class OP >
const LinearProblem<ScalarType,MV,OP>& Belos::BlockGCRODRSolMgr< ScalarType, MV, OP >::getProblem ( ) const [inline, virtual]

Get current linear problem being solved for in this object.

Implements Belos::SolverManager< ScalarType, MV, OP >.

Definition at line 242 of file BelosBlockGCRODRSolMgr.hpp.

template<class ScalarType , class MV , class OP >
Teuchos::RCP< const Teuchos::ParameterList > Belos::BlockGCRODRSolMgr< ScalarType, MV, OP >::getValidParameters ( ) const [virtual]

Get a parameter list containing the valid parameters for this object.

Implements Belos::SolverManager< ScalarType, MV, OP >.

Definition at line 658 of file BelosBlockGCRODRSolMgr.hpp.

template<class ScalarType , class MV , class OP >
Teuchos::RCP<const Teuchos::ParameterList> Belos::BlockGCRODRSolMgr< ScalarType, MV, OP >::getCurrentParameters ( ) const [inline, virtual]

Get a parameter list containing the current parameters for this object.

Implements Belos::SolverManager< ScalarType, MV, OP >.

Definition at line 250 of file BelosBlockGCRODRSolMgr.hpp.

template<class ScalarType , class MV , class OP >
int Belos::BlockGCRODRSolMgr< ScalarType, MV, OP >::getNumIters ( ) const [inline, virtual]

Get the iteration count for the most recent call to solve().

Implements Belos::SolverManager< ScalarType, MV, OP >.

Definition at line 256 of file BelosBlockGCRODRSolMgr.hpp.

template<class ScalarType , class MV , class OP >
bool Belos::BlockGCRODRSolMgr< ScalarType, MV, OP >::isLOADetected ( ) const [inline, virtual]

Whether a loss of accuracy was detected during the most recent solve.

Implements Belos::SolverManager< ScalarType, MV, OP >.

Definition at line 261 of file BelosBlockGCRODRSolMgr.hpp.

template<class ScalarType , class MV , class OP >
void Belos::BlockGCRODRSolMgr< ScalarType, MV, OP >::setProblem ( const Teuchos::RCP< LinearProblem< ScalarType, MV, OP > > &  problem) [inline, virtual]

Set the linear problem to solve on the next call to solve().

Warning:
(mfh 03 Jan 2012) For whatever reason, the original author provided a trivial implementation of this method (it just returned without doing anything). This probably means that it doesn't work at all. I've done my best to provide a sensible implementation.

Implements Belos::SolverManager< ScalarType, MV, OP >.

Definition at line 276 of file BelosBlockGCRODRSolMgr.hpp.

template<class ScalarType , class MV , class OP >
void Belos::BlockGCRODRSolMgr< ScalarType, MV, OP >::setParameters ( const Teuchos::RCP< Teuchos::ParameterList > &  params) [virtual]

Set the parameters the solver should use to solve the linear problem.

Implements Belos::SolverManager< ScalarType, MV, OP >.

Definition at line 746 of file BelosBlockGCRODRSolMgr.hpp.

template<class ScalarType , class MV , class OP >
void Belos::BlockGCRODRSolMgr< ScalarType, MV, OP >::reset ( const ResetType  type) [inline, virtual]

Performs a reset of the solver manager specified by the ResetType.

This informs the solver manager that the solver should prepare for the next call to solve by resetting certain elements of the iterative solver strategy.

Warning:
(mfh 03 Jan 2012) For whatever reason, the original author provided a trivial implementation of this method (it just returned without doing anything). This probably means that it doesn't work at all. I've done my best to provide a sensible implementation.

Implements Belos::SolverManager< ScalarType, MV, OP >.

Definition at line 333 of file BelosBlockGCRODRSolMgr.hpp.

template<class ScalarType , class MV , class OP >
ReturnType Belos::BlockGCRODRSolMgr< ScalarType, MV, OP >::solve ( ) [virtual]

Solve the current linear problem.

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 BlockGCRODRIter::iterate(), which will return either because a specially constructed status test evaluates to Passed or an exception is thrown.

A return from BlockGCRODRIter::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. - 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.

Implements Belos::SolverManager< ScalarType, MV, OP >.

Definition at line 1924 of file BelosBlockGCRODRSolMgr.hpp.


The documentation for this class was generated from the following file:
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