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

The Belos::PCPGSolMgr manages the PCPG linear solver. Three Hypotheses: First users must ensure that for each linear system has the same coefficient matrix! Second the seed space is invariant during an individual linear system solve. Third, due to finite precision arithmetic, the off-diaognal "P'AP" terms grow. More...

#include <BelosPCPGSolMgr.hpp>

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

Public Member Functions

Constructors/Destructor
 PCPGSolMgr ()
 Empty constructor for PCPGSolMgr. 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. In most instances, LinearProblem setProblem(...) methods are used. Solver values may be changed using setParameters().
 PCPGSolMgr (const Teuchos::RCP< LinearProblem< ScalarType, MV, OP > > &problem, const Teuchos::RCP< Teuchos::ParameterList > &pl)
 Basic constructor for PCPGSolMgr. The constructor accepts a LinearProblem to be solved and a parameter list of these options:
virtual ~PCPGSolMgr ()
 Destructor.
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.
Teuchos::Array< Teuchos::RCP
< Teuchos::Time > > 
getTimers () const
 Return the timers for this object.
int getNumIters () const
 Get the iteration count for the most recent call to solve().
bool isLOADetected () const
 Return whether a loss of accuracy was detected by this solver during the most current solve.
Set methods
void setProblem (const Teuchos::RCP< LinearProblem< ScalarType, MV, OP > > &problem)
 Set the linear problem that needs to be solved.
void setParameters (const Teuchos::RCP< Teuchos::ParameterList > &params)
 Set the parameters the solver manager 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. 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.
Solver application methods
ReturnType solve ()
 The method either solves the problem or decides to quit. On each call, a (possibly null) seed space is used to accelerate convergence.
Overridden from Teuchos::Describable
std::string description () const
 Method to return description of the PCPG solver manager.

Detailed Description

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

The Belos::PCPGSolMgr manages the PCPG linear solver. Three Hypotheses: First users must ensure that for each linear system has the same coefficient matrix! Second the seed space is invariant during an individual linear system solve. Third, due to finite precision arithmetic, the off-diaognal "P'AP" terms grow.

Author:
David Day

Definition at line 137 of file BelosPCPGSolMgr.hpp.


Constructor & Destructor Documentation

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

Empty constructor for PCPGSolMgr. 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. In most instances, LinearProblem setProblem(...) methods are used. Solver values may be changed using setParameters().

Definition at line 385 of file BelosPCPGSolMgr.hpp.

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

Basic constructor for PCPGSolMgr. The constructor accepts a LinearProblem to be solved and a parameter list of these options:

  • "Num Deflated Blocks" - a int specifying the number of blocks deflated from the linear system. Default: 2 The parameter distinguishes PCPG from CG.
  • "Num Saved Blocks" - a int specifying the maximum number of blocks saved from old Krylov bases. Default: 16 The parameter distinguishes PCPG from CG.
  • "Block Size" - an int specifying the block size to be used by the underlying block conjugate-gradient solver. In PCPC block size = one. Many parameters are meaningless in the unit block size case. Default: 1
  • "Adaptive Block Size" - a bool specifying whether the block size can be modified throughout the solve. Default: true Meaningless with unit block size
  • "Maximum Iterations" - an int specifying the maximum number of iterations the underlying solver is allowed to perform. Default: 1000
  • "Convergence Tolerance" - a MagnitudeType specifying the level that residual norms must reach to decide convergence. Default: 1e-8.
  • "Orthogonalization" - a string specifying the desired orthogonalization: DGKS, ICGS, IMGS. Default: "DGKS" Meaningless with unit block size
  • "Orthogonalization Constant" - a MagnitudeType used by DGKS orthogonalization to determine whether another step of classical Gram-Schmidt is necessary. Default: -1 (use DGKS default) Meaningless with unit block size
  • "Verbosity" - a sum of MsgType specifying the verbosity. Default: Belos::Errors
  • "Output Style" - a OutputType specifying the style of output. Default: Belos::General
  • "Output Stream" - a reference-counted pointer to the output stream where all solver output is sent. Default: Teuchos::rcp(&std::cout,false)
  • "Output Frequency" - an int specifying how often convergence information should be outputted. Default: -1 (never)
  • "Show Maximum Residual Norm Only" - a bool specifying whether that only the maximum relative residual norm is printed if convergence information is printed. Default: false Meaningless with unit block size
  • "Timer Label" - a std::string to use as a prefix for the timer labels. Default: "Belos"

Definition at line 403 of file BelosPCPGSolMgr.hpp.

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

Destructor.

Definition at line 198 of file BelosPCPGSolMgr.hpp.


Member Function Documentation

template<class ScalarType , class MV , class OP >
const LinearProblem<ScalarType,MV,OP>& Belos::PCPGSolMgr< 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 206 of file BelosPCPGSolMgr.hpp.

template<class ScalarType , class MV , class OP >
Teuchos::RCP< const Teuchos::ParameterList > Belos::PCPGSolMgr< 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 653 of file BelosPCPGSolMgr.hpp.

template<class ScalarType , class MV , class OP >
Teuchos::RCP<const Teuchos::ParameterList> Belos::PCPGSolMgr< 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 216 of file BelosPCPGSolMgr.hpp.

template<class ScalarType , class MV , class OP >
Teuchos::Array<Teuchos::RCP<Teuchos::Time> > Belos::PCPGSolMgr< ScalarType, MV, OP >::getTimers ( ) const [inline]

Return the timers for this object.

The timers are ordered as follows:

Definition at line 223 of file BelosPCPGSolMgr.hpp.

template<class ScalarType , class MV , class OP >
int Belos::PCPGSolMgr< 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 228 of file BelosPCPGSolMgr.hpp.

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

Return whether a loss of accuracy was detected by this solver during the most current solve.

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

Definition at line 234 of file BelosPCPGSolMgr.hpp.

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

Set the linear problem that needs to be solved.

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

Definition at line 242 of file BelosPCPGSolMgr.hpp.

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

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

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

Definition at line 430 of file BelosPCPGSolMgr.hpp.

template<class ScalarType , class MV , class OP >
void Belos::PCPGSolMgr< 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.

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

Definition at line 255 of file BelosPCPGSolMgr.hpp.

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

The method either solves the problem or decides to quit. On each call, a (possibly null) seed space is used to accelerate convergence.

The method calls PCPGIter::iterate(), which will return either because a specially constructed status test evaluates to Passed or an exception is thrown. The first Krylov vectors are appended to the seed space.

A return from PCPGIter::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.

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

Definition at line 697 of file BelosPCPGSolMgr.hpp.

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

Method to return description of the PCPG solver manager.

Reimplemented from Teuchos::Describable.

Definition at line 1155 of file BelosPCPGSolMgr.hpp.


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