Inheritance diagram for Belos::PseudoBlockGmresIter< Sacado::MP::Vector< Storage >, MV, OP >:

Collaboration diagram for Belos::PseudoBlockGmresIter< Sacado::MP::Vector< Storage >, MV, OP >:

Public Types
typedef Sacado::MP::Vector < Storage >	ScalarType

typedef MultiVecTraits < ScalarType, MV >	MVT

typedef OperatorTraits < ScalarType, MV, OP >	OPT

typedef Teuchos::ScalarTraits < ScalarType >	SCT

typedef SCT::magnitudeType	MagnitudeType

typedef Teuchos::ScalarTraits < typename Storage::value_type >	SVT

Public Member Functions
Constructors/Destructor
	PseudoBlockGmresIter (const Teuchos::RCP< LinearProblem< ScalarType, MV, OP > > &problem, const Teuchos::RCP< OutputManager< ScalarType > > &printer, const Teuchos::RCP< StatusTest< ScalarType, MV, OP > > &tester, const Teuchos::RCP< MatOrthoManager< ScalarType, MV, OP > > &ortho, Teuchos::ParameterList &params)
	PseudoBlockGmresIter constructor with linear problem, solver utilities, and parameter list of solver options. More...

virtual	~PseudoBlockGmresIter ()=default
	Destructor.

Solver methods
void	iterate ()
	This method performs block Gmres iterations until the status test indicates the need to stop or an error occurs (in which case, an std::exception is thrown). More...

void	initialize (const PseudoBlockGmresIterState< ScalarType, MV > &newstate)
	Initialize the solver to an iterate, providing a complete state. More...

void	initialize ()
	Initialize the solver with the initial vectors from the linear problem or random data.

PseudoBlockGmresIterState < ScalarType, MV >	getState () const
	Get the current state of the linear solver. More...

Status methods
int	getNumIters () const
	Get the current iteration count.

void	resetNumIters (int iter=0)
	Reset the iteration count.

Teuchos::RCP< const MV >	getNativeResiduals (std::vector< MagnitudeType > *norms) const
	Get the norms of the "native" residual vectors. More...

Teuchos::RCP< MV >	getCurrentUpdate () const
	Get the current update to the linear system. More...

void	updateLSQR (int dim=-1)
	Method for updating QR factorization of upper Hessenberg matrix. More...

int	getCurSubspaceDim () const
	Get the dimension of the search subspace used to generate the current solution to the linear problem.

int	getMaxSubspaceDim () const
	Get the maximum dimension allocated for the search subspace.

Accessor methods
const LinearProblem < ScalarType, MV, OP > &	getProblem () const
	Get a constant reference to the linear problem.

int	getBlockSize () const
	Get the blocksize to be used by the iterative solver in solving this linear problem.

void	setBlockSize (int blockSize)
	Set the blocksize.

int	getNumBlocks () const
	Get the maximum number of blocks used by the iterative solver in solving this linear problem.

void	setNumBlocks (int numBlocks)
	Set the maximum number of blocks used by the iterative solver.

bool	isInitialized ()
	States whether the solver has been initialized or not.

Constructor & Destructor Documentation

template<class Storage , class MV , class OP >

Belos::PseudoBlockGmresIter< Sacado::MP::Vector< Storage >, MV, OP >::PseudoBlockGmresIter	(	const Teuchos::RCP< LinearProblem< ScalarType, MV, OP > > &	problem,
		const Teuchos::RCP< OutputManager< ScalarType > > &	printer,
		const Teuchos::RCP< StatusTest< ScalarType, MV, OP > > &	tester,
		const Teuchos::RCP< MatOrthoManager< ScalarType, MV, OP > > &	ortho,
		Teuchos::ParameterList &	params
	)

PseudoBlockGmresIter constructor with linear problem, solver utilities, and parameter list of solver options.

This constructor takes pointers required by the linear solver, in addition to a parameter list of options for the linear solver. These options include the following:

"Block Size" - an int specifying the block size used by the algorithm. This can also be specified using the setBlockSize() method. Default: 1
"Num Blocks" - an int specifying the maximum number of blocks allocated for the solver basis. Default: 25
"Restart Timers" = a bool specifying whether the timers should be restarted each time iterate() is called. Default: false

Member Function Documentation

template<class Storage , class MV , class OP >

Teuchos::RCP<MV> Belos::PseudoBlockGmresIter< Sacado::MP::Vector< Storage >, MV, OP >::getCurrentUpdate ( ) const

Get the current update to the linear system.

Note: Some solvers, like GMRES, do not compute updates to the solution every iteration. This method forces its computation. Other solvers, like CG, update the solution each iteration, so this method will return a zero vector indicating that the linear problem contains the current solution.

template<class Storage , class MV , class OP >

Teuchos::RCP<const MV> Belos::PseudoBlockGmresIter< Sacado::MP::Vector< Storage >, MV, OP >::getNativeResiduals ( std::vector< MagnitudeType > * norms ) const

Get the norms of the "native" residual vectors.

If norms != NULL, fill *norms with the native residual norms. There are numRHS_ of them. *norms will be resized if it has too few entries to hold the data.

For an explanation of "native" vs. "exact" (also known as "implicit" vs. "explicit") residuals, see the documentation of PseudoBlockGmresSolMgr::isLOADetected(). In brief: "Native" residuals are cheaper to compute than "exact" residuals, but the two may differ, especially when using a left preconditioner.

Returns: Teuchos::null (always, regardless whether norms == NULL). We only return something in order to satisfy the Iteration interface. PseudoBlockGmresSolMgr knows that this method always returns null.

template<class Storage , class MV , class OP >

PseudoBlockGmresIterState<ScalarType,MV> Belos::PseudoBlockGmresIter< Sacado::MP::Vector< Storage >, MV, OP >::getState ( ) const

inline

Get the current state of the linear solver.

The data is only valid if isInitialized() == true.

Returns: A PseudoBlockGmresIterState object containing const pointers to the current solver state.

template<class Storage , class MV , class OP >

void Belos::PseudoBlockGmresIter< Sacado::MP::Vector< Storage >, MV, OP >::initialize ( const PseudoBlockGmresIterState< ScalarType, MV > & newstate )

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

The PseudoBlockGmresIter contains a certain amount of state, consisting of the current Krylov basis and the associated Hessenberg matrix.

initialize() gives the user the opportunity to manually set these, although this must be done with caution, abiding by the rules given below. All notions of orthogonality and orthonormality are derived from the inner product specified by the orthogonalization manager.

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

The user has the option of specifying any component of the state using initialize(). However, these arguments are assumed to match the post-conditions specified under isInitialized(). Any necessary component of the state not given to initialize() will be generated.

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

template<class Storage , class MV , class OP >

void Belos::PseudoBlockGmresIter< Sacado::MP::Vector< Storage >, MV, OP >::iterate ( )

This method performs block Gmres iterations until the status test indicates the need to stop or an error occurs (in which case, an std::exception is thrown).

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

The block Gmres iteration proceeds as follows:

The operator problem->applyOp() is applied to the newest blockSize vectors in the Krylov basis.
The resulting vectors are orthogonalized against the previous basis vectors, and made orthonormal.
The Hessenberg matrix is updated.
The least squares system is updated.

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

Possible exceptions thrown include the PseudoBlockGmresIterOrthoFailure.

template<class Storage , class MV , class OP >

void Belos::PseudoBlockGmresIter< Sacado::MP::Vector< Storage >, MV, OP >::updateLSQR ( int dim = -1 )

Method for updating QR factorization of upper Hessenberg matrix.

Note: If dim >= getCurSubspaceDim() and dim < getMaxSubspaceDim(), then the dim-th equations of the least squares problem will be updated.

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

Belos_PseudoBlockGmresIter_MP_Vector.hpp

Public Types

Public Member Functions

Constructor & Destructor Documentation

Member Function Documentation