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

MINRES implementation. More...

#include <BelosMinresIter.hpp>

Inheritance diagram for Belos::MinresIter< ScalarType, MV, OP >:

Public Types
typedef MultiVecTraits < ScalarType, MV >	MVT
typedef OperatorTraits < ScalarType, MV, OP >	OPT
typedef Teuchos::ScalarTraits < ScalarType >	SCT
typedef SCT::magnitudeType	MagnitudeType
typedef Teuchos::ScalarTraits < MagnitudeType >	SMT

Private Member Functions
void	setStateSize ()
	Method for initalizing the state storage needed by MINRES. More...

Private Attributes
const Teuchos::RCP < LinearProblem< ScalarType, MV, OP > >	lp_
const Teuchos::RCP < OutputManager< ScalarType > >	om_
const Teuchos::RCP< StatusTest < ScalarType, MV, OP > >	stest_
bool	initialized_
	Whether the solver has been initialized. More...
bool	stateStorageInitialized_
	Whether the state storage has been initialized. More...
int	iter_
	Current number of iterations performed. More...
MagnitudeType	phibar_
Teuchos::RCP< MV >	Y_
	Preconditioned residual. More...
Teuchos::RCP< MV >	R1_
	Previous residual. More...
Teuchos::RCP< MV >	R2_
	Previous residual. More...
Teuchos::RCP< MV >	W_
	Direction vector. More...
Teuchos::RCP< MV >	W1_
	Previous direction vector. More...
Teuchos::RCP< MV >	W2_
	Previous direction vector. More...
Teuchos::SerialDenseMatrix < int, ScalarType >	beta1_
	Coefficient in the MINRES iteration. More...

Constructors/Destructor
	MinresIter (const Teuchos::RCP< LinearProblem< ScalarType, MV, OP > > &problem, const Teuchos::RCP< OutputManager< ScalarType > > &printer, const Teuchos::RCP< StatusTest< ScalarType, MV, OP > > &tester, const Teuchos::ParameterList &params)
	Constructor. More...
virtual	~MinresIter ()
	Destructor. More...

Solver methods
void	iterate ()
	Perform MINRES iterations until convergence or error. More...
void	initializeMinres (const MinresIterationState< ScalarType, MV > &newstate)
	Initialize the solver to an iterate, providing a complete state. More...
void	initialize ()
	Initialize the solver. More...
MinresIterationState < ScalarType, MV >	getState () const
	Get the current state of the linear solver. More...

Status methods
int	getNumIters () const
	Get the current iteration count. More...
void	resetNumIters (int iter=0)
	Reset the iteration count. More...
Teuchos::RCP< const MV >	getNativeResiduals (std::vector< MagnitudeType > *norms) const
	Get the norms of the residuals native to the solver. More...
Teuchos::RCP< MV >	getCurrentUpdate () const
	Get the current update to the linear system. More...
void	symOrtho (ScalarType a, ScalarType b, ScalarType *c, ScalarType *s, ScalarType *r)

Accessor methods
const LinearProblem < ScalarType, MV, OP > &	getProblem () const
	Get a constant reference to the linear problem. More...
int	getBlockSize () const
	Get the blocksize to be used by the iterative solver in solving this linear problem. More...
void	setBlockSize (int blockSize)
	Set the blocksize to be used by the iterative solver in solving this linear problem. More...
bool	isInitialized () const
	States whether the solver has been initialized or not. More...
bool	isInitialized ()
	States whether the solver has been initialized or not. More...

Detailed Description

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

MINRES implementation.

Author

Nico Schl"omer

Implementation of the preconditioned Minimal Residual Method (MINRES) iteration. This a bilinear form implementation, that uses inner products of the form <x,My> to solve the preconditioned linear system. Thus, it is necessary that the left preconditioner M is positive definite.

Definition at line 62 of file BelosMinresIter.hpp.

Member Typedef Documentation

template<class ScalarType , class MV , class OP >

typedef MultiVecTraits< ScalarType, MV > Belos::MinresIter< ScalarType, MV, OP >::MVT

Definition at line 69 of file BelosMinresIter.hpp.

template<class ScalarType , class MV , class OP >

typedef OperatorTraits< ScalarType, MV, OP > Belos::MinresIter< ScalarType, MV, OP >::OPT

Definition at line 70 of file BelosMinresIter.hpp.

template<class ScalarType , class MV , class OP >

typedef Teuchos::ScalarTraits< ScalarType > Belos::MinresIter< ScalarType, MV, OP >::SCT

Definition at line 71 of file BelosMinresIter.hpp.

template<class ScalarType , class MV , class OP >

typedef SCT::magnitudeType Belos::MinresIter< ScalarType, MV, OP >::MagnitudeType

Definition at line 72 of file BelosMinresIter.hpp.

template<class ScalarType , class MV , class OP >

typedef Teuchos::ScalarTraits< MagnitudeType > Belos::MinresIter< ScalarType, MV, OP >::SMT

Definition at line 73 of file BelosMinresIter.hpp.

Constructor & Destructor Documentation

template<class ScalarType , class MV , class OP >

Belos::MinresIter< ScalarType, MV, OP >::MinresIter	(	const Teuchos::RCP< LinearProblem< ScalarType, MV, OP > > &	problem,
		const Teuchos::RCP< OutputManager< ScalarType > > &	printer,
		const Teuchos::RCP< StatusTest< ScalarType, MV, OP > > &	tester,
		const Teuchos::ParameterList &	params
	)

Constructor.

problem The linear problem to solve printer Output manager, for intermediate solver output tester Status test for determining when the current approximate solution has converged params Parameter list of solver options

Definition at line 293 of file BelosMinresIter.hpp.

template<class ScalarType , class MV , class OP >

virtual Belos::MinresIter< ScalarType, MV, OP >::~MinresIter ( )

inlinevirtual

Destructor.

Definition at line 92 of file BelosMinresIter.hpp.

Member Function Documentation

template<class ScalarType , class MV , class OP >

void Belos::MinresIter< ScalarType, MV, OP >::iterate ( )

virtual

Perform MINRES iterations until convergence or error.

Perform MINRES iterations until the status test indicates the need to stop, or until an error occurs. In the latter case, a (subclass of) std::exception is thrown.

iterate() will first determine whether the solver is initialized; if not, it will call initialize() using default arguments. After initialization, the solver performs MINRES iterations until the status test evaluates as Passed, at which point the method returns to the caller.

The status test is queried at the beginning of the iteration.

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

Definition at line 426 of file BelosMinresIter.hpp.

template<class ScalarType , class MV , class OP >

void Belos::MinresIter< ScalarType, MV, OP >::initializeMinres ( const MinresIterationState< ScalarType, MV > &  newstate )

virtual

Initialize the solver to an iterate, providing a complete state.

The MinresIter contains a certain amount of state, consisting of the current residual, preconditioned residual, and decent direction.

initialize() gives the user the opportunity to manually set these, although only the current unpreconditioned residual is required.

Postcondition

isInitialized() == true (see post-conditions of isInitialize())

Note

For any pointer in newstate which directly points to the multivectors in the solver, the data is not copied.

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

Definition at line 348 of file BelosMinresIter.hpp.

template<class ScalarType , class MV , class OP >

void Belos::MinresIter< ScalarType, MV, OP >::initialize ( )

inlinevirtual

Initialize the solver.

Initialize the solver. If a starting guess is provided in the linear problem, use that. Otherwise, choose a random starting guess.

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

Definition at line 136 of file BelosMinresIter.hpp.

template<class ScalarType , class MV , class OP >

MinresIterationState<ScalarType,MV> Belos::MinresIter< ScalarType, MV, OP >::getState ( ) const

inlinevirtual

Get the current state of the linear solver.

The returned current state is only valid if isInitialized() == true.

Returns

A MinresIterationState object containing const pointers to the current solver state.

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

Definition at line 148 of file BelosMinresIter.hpp.

template<class ScalarType , class MV , class OP >

int Belos::MinresIter< ScalarType, MV, OP >::getNumIters ( ) const

inlinevirtual

Get the current iteration count.

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

Definition at line 169 of file BelosMinresIter.hpp.

template<class ScalarType , class MV , class OP >

void Belos::MinresIter< ScalarType, MV, OP >::resetNumIters ( int  iter = 0 )

inlinevirtual

Reset the iteration count.

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

Definition at line 172 of file BelosMinresIter.hpp.

template<class ScalarType , class MV , class OP >

Teuchos::RCP<const MV> Belos::MinresIter< ScalarType, MV, OP >::getNativeResiduals ( std::vector< MagnitudeType > *  norms ) const

inline

Get the norms of the residuals native to the solver.

Returns

A std::vector of length blockSize containing the native residuals.

Definition at line 177 of file BelosMinresIter.hpp.

template<class ScalarType , class MV , class OP >

Teuchos::RCP<MV> Belos::MinresIter< ScalarType, MV, OP >::getCurrentUpdate ( ) const

inlinevirtual

Get the current update to the linear system.

Note

This method returns a null pointer because the linear problem is current.

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

Definition at line 192 of file BelosMinresIter.hpp.

template<class ScalarType , class MV , class OP >

void Belos::MinresIter< ScalarType, MV, OP >::symOrtho	(	ScalarType	a,
		ScalarType	b,
		ScalarType *	c,
		ScalarType *	s,
		ScalarType *	r
	)

Definition at line 582 of file BelosMinresIter.hpp.

template<class ScalarType , class MV , class OP >

const LinearProblem<ScalarType,MV,OP>& Belos::MinresIter< ScalarType, MV, OP >::getProblem ( ) const

inlinevirtual

Get a constant reference to the linear problem.

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

Definition at line 203 of file BelosMinresIter.hpp.

template<class ScalarType , class MV , class OP >

int Belos::MinresIter< ScalarType, MV, OP >::getBlockSize ( ) const

inlinevirtual

Get the blocksize to be used by the iterative solver in solving this linear problem.

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

Definition at line 206 of file BelosMinresIter.hpp.

template<class ScalarType , class MV , class OP >

void Belos::MinresIter< ScalarType, MV, OP >::setBlockSize ( int  blockSize )

inlinevirtual

Set the blocksize to be used by the iterative solver in solving this linear problem.

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

Definition at line 209 of file BelosMinresIter.hpp.

template<class ScalarType , class MV , class OP >

bool Belos::MinresIter< ScalarType, MV, OP >::isInitialized ( ) const

inline

States whether the solver has been initialized or not.

Definition at line 215 of file BelosMinresIter.hpp.

template<class ScalarType , class MV , class OP >

bool Belos::MinresIter< ScalarType, MV, OP >::isInitialized ( )

inlinevirtual

States whether the solver has been initialized or not.

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

Definition at line 216 of file BelosMinresIter.hpp.

template<class ScalarType , class MV , class OP >

void Belos::MinresIter< ScalarType, MV, OP >::setStateSize ( )

private

Method for initalizing the state storage needed by MINRES.

Definition at line 310 of file BelosMinresIter.hpp.

Member Data Documentation

template<class ScalarType , class MV , class OP >

const Teuchos::RCP< LinearProblem< ScalarType, MV, OP > > Belos::MinresIter< ScalarType, MV, OP >::lp_

private

Definition at line 231 of file BelosMinresIter.hpp.

template<class ScalarType , class MV , class OP >

const Teuchos::RCP< OutputManager< ScalarType > > Belos::MinresIter< ScalarType, MV, OP >::om_

private

Definition at line 232 of file BelosMinresIter.hpp.

template<class ScalarType , class MV , class OP >

const Teuchos::RCP< StatusTest< ScalarType, MV, OP > > Belos::MinresIter< ScalarType, MV, OP >::stest_

private

Definition at line 233 of file BelosMinresIter.hpp.

template<class ScalarType , class MV , class OP >

bool Belos::MinresIter< ScalarType, MV, OP >::initialized_

private

Whether the solver has been initialized.

If initialized_ == true, then the basis vectors have been initialized and the iterate() routine is capable of running. initialize is set by the initialize() member method. For the implications of the state of initialized, please see documentation for initialize().

Definition at line 243 of file BelosMinresIter.hpp.

template<class ScalarType , class MV , class OP >

bool Belos::MinresIter< ScalarType, MV, OP >::stateStorageInitialized_

private

Whether the state storage has been initialized.

If stateStorageInitialized_ == true, then the state storage has been initialized. This initialization may be postponed if the linear problem was generated without the right-hand side or solution vectors.

Definition at line 251 of file BelosMinresIter.hpp.

template<class ScalarType , class MV , class OP >

int Belos::MinresIter< ScalarType, MV, OP >::iter_

private

Current number of iterations performed.

Definition at line 254 of file BelosMinresIter.hpp.

template<class ScalarType , class MV , class OP >

MagnitudeType Belos::MinresIter< ScalarType, MV, OP >::phibar_

private

Definition at line 260 of file BelosMinresIter.hpp.

template<class ScalarType , class MV , class OP >

Teuchos::RCP< MV > Belos::MinresIter< ScalarType, MV, OP >::Y_

private

Preconditioned residual.

Definition at line 267 of file BelosMinresIter.hpp.

template<class ScalarType , class MV , class OP >

Teuchos::RCP< MV > Belos::MinresIter< ScalarType, MV, OP >::R1_

private

Previous residual.

Definition at line 269 of file BelosMinresIter.hpp.

template<class ScalarType , class MV , class OP >

Teuchos::RCP< MV > Belos::MinresIter< ScalarType, MV, OP >::R2_

private

Previous residual.

Definition at line 271 of file BelosMinresIter.hpp.

template<class ScalarType , class MV , class OP >

Teuchos::RCP< MV > Belos::MinresIter< ScalarType, MV, OP >::W_

private

Direction vector.

Definition at line 273 of file BelosMinresIter.hpp.

template<class ScalarType , class MV , class OP >

Teuchos::RCP< MV > Belos::MinresIter< ScalarType, MV, OP >::W1_

private

Previous direction vector.

Definition at line 275 of file BelosMinresIter.hpp.

template<class ScalarType , class MV , class OP >

Teuchos::RCP< MV > Belos::MinresIter< ScalarType, MV, OP >::W2_

private

Previous direction vector.

Definition at line 277 of file BelosMinresIter.hpp.

template<class ScalarType , class MV , class OP >

Teuchos::SerialDenseMatrix<int,ScalarType> Belos::MinresIter< ScalarType, MV, OP >::beta1_

private

Coefficient in the MINRES iteration.

Note

If we could be sure that the preconditioner is Hermitian in complex arithmetic (which must be true anyway, in order for MINRES to work), we could make beta1_ a MagnitudeType. This would certainly be cleaner, considering it will be copied into beta (which is of MagnitudeType).

Definition at line 286 of file BelosMinresIter.hpp.

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

• BelosMinresIter.hpp