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

This class implements the PCPG iteration, where a single-std::vector Krylov subspace is constructed. The documentation refers to blocks, but note that at this point, all blocks have unit dimension. More...

#include <BelosPCPGIter.hpp>

Inheritance diagram for Belos::PCPGIter< 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

Private Member Functions
void	setStateSize ()
	Method for initalizing the state storage needed by PCPG. 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_
const Teuchos::RCP < OrthoManager< ScalarType, MV > >	ortho_
int	savedBlocks_
bool	initialized_
bool	stateStorageInitialized_
bool	keepDiagonal_
bool	initDiagonal_
int	curDim_
int	prevUdim_
int	iter_
Teuchos::RCP< MV >	R_
Teuchos::RCP< MV >	Z_
Teuchos::RCP< MV >	P_
Teuchos::RCP< MV >	AP_
Teuchos::RCP< MV >	U_
Teuchos::RCP< MV >	C_
Teuchos::RCP < Teuchos::SerialDenseMatrix < int, ScalarType > >	D_

Constructors/Destructor
	PCPGIter (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)
	PCPGIter constructor with linear problem, solver utilities, and parameter list of solver options. More...
virtual	~PCPGIter ()
	Destructor. More...

Solver methods
void	iterate ()
	PCPGIter iterates CG until the status test either requests a stop or detects an error. In the latter case, std::exception is thrown. More...
void	initialize (PCPGIterState< 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. An exception is thrown if initialzed is called and newstate.R is null. More...
PCPGIterState< 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 > *) 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 solution?. More...
int	getCurSubspaceDim () const
	Get the current dimension of the whole seed subspace. More...
int	getPrevSubspaceDim () const
	Get the dimension of the search subspace used to solve the current solution to the linear problem. More...

Accessor methods
const LinearProblem < ScalarType, MV, OP > &	getProblem () const
	Get a constant reference to the linear problem. More...
int	getBlockSize () const
	Get the maximum number of blocks used by the iterative solver in solving this linear problem. More...
int	getNumRecycledBlocks () const
	Get the maximum number of recycled blocks used by the iterative solver in solving this linear problem. More...
void	setBlockSize (int blockSize)
	Get the blocksize to be used by the iterative solver in solving this linear problem. More...
void	setSize (int savedBlocks)
	Set the maximum number of saved or recycled blocks used by the iterative solver. More...
bool	isInitialized ()
	States whether the solver has been initialized or not. More...
void	resetState ()
	tell the Iterator to "reset" itself; delete and rebuild the seed space. More...

Detailed Description

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

This class implements the PCPG iteration, where a single-std::vector Krylov subspace is constructed. The documentation refers to blocks, but note that at this point, all blocks have unit dimension.

Author

David Day

Definition at line 101 of file BelosPCPGIter.hpp.

Member Typedef Documentation

template<class ScalarType , class MV , class OP >

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

Definition at line 108 of file BelosPCPGIter.hpp.

template<class ScalarType , class MV , class OP >

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

Definition at line 109 of file BelosPCPGIter.hpp.

template<class ScalarType , class MV , class OP >

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

Definition at line 110 of file BelosPCPGIter.hpp.

template<class ScalarType , class MV , class OP >

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

Definition at line 111 of file BelosPCPGIter.hpp.

Constructor & Destructor Documentation

template<class ScalarType , class MV , class OP >

Belos::PCPGIter< ScalarType, MV, OP >::PCPGIter	(	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
	)

PCPGIter 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:

• "Restart Timers" = a bool specifying whether the timers should be restarted each time iterate() is called. Default: false
• "Keep Diagonal" = a bool specifying whether the upper Hessenberg should be stored separately from the least squares system. Default: false

Definition at line 353 of file BelosPCPGIter.hpp.

template<class ScalarType , class MV , class OP >

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

inlinevirtual

Destructor.

Definition at line 130 of file BelosPCPGIter.hpp.

Member Function Documentation

template<class ScalarType , class MV , class OP >

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

virtual

PCPGIter iterates CG until the status test either requests a stop or detects an error. In the latter case, std::exception is thrown.

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

The PCPG iteration proceeds as follows:

1. the operator problem->applyOp() is applied to the newest vector in the Krylov basis,
2. the result is (approximately) A-orthogonalized to the previous basis vectors,
3. the coupled two-term recurrence is iterated,
4. the search direction P is projected into a complement of the seed space U.

The status test is queried at the beginning of the iteration. Potential CG exceptions include IterationInit, Iterate

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

Definition at line 594 of file BelosPCPGIter.hpp.

template<class ScalarType , class MV , class OP >

void Belos::PCPGIter< ScalarType, MV, OP >::initialize

(

PCPGIterState< ScalarType, MV > &

newstate

)

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

The PCPGIter state consists of the CGIter state, the stored search directions and the seed space. The constructor calls setSize() which calls setStateSize().

initialize(IterState) also calls setStateSize(), passing the current seed space to Iterate. initialize(IterState) sets the state to the specified IterState and then initialized_ := true. Fundamental state changes cause initialized_ := false.

Postcondition

isInitialized() == true

Optionally, the user may specify any component of the state using initialize(). Any 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 (supposed to be) copied.

Definition at line 506 of file BelosPCPGIter.hpp.

template<class ScalarType , class MV , class OP >

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

inlinevirtual

Initialize the solver with the initial vectors from the linear problem. An exception is thrown if initialzed is called and newstate.R is null.

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

Definition at line 180 of file BelosPCPGIter.hpp.

template<class ScalarType , class MV , class OP >

PCPGIterState<ScalarType,MV> Belos::PCPGIter< ScalarType, MV, OP >::getState ( ) const

inline

Get the current state of the linear solver.

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

Returns

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

Definition at line 193 of file BelosPCPGIter.hpp.

template<class ScalarType , class MV , class OP >

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

inlinevirtual

Get the current iteration count.

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

Definition at line 214 of file BelosPCPGIter.hpp.

template<class ScalarType , class MV , class OP >

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

inlinevirtual

Reset the iteration count.

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

Definition at line 217 of file BelosPCPGIter.hpp.

template<class ScalarType , class MV , class OP >

Teuchos::RCP<const MV> Belos::PCPGIter< ScalarType, MV, OP >::getNativeResiduals ( std::vector< MagnitudeType > *  ) 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 221 of file BelosPCPGIter.hpp.

template<class ScalarType , class MV , class OP >

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

inlinevirtual

Get the current update to the linear system solution?.

Note

getCurrentUpdate returns a null pointer indicating that the linear problem contains the current solution.

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

Definition at line 227 of file BelosPCPGIter.hpp.

template<class ScalarType , class MV , class OP >

int Belos::PCPGIter< ScalarType, MV, OP >::getCurSubspaceDim ( ) const

inline

Get the current dimension of the whole seed subspace.

Definition at line 230 of file BelosPCPGIter.hpp.

template<class ScalarType , class MV , class OP >

int Belos::PCPGIter< ScalarType, MV, OP >::getPrevSubspaceDim ( ) const

inline

Get the dimension of the search subspace used to solve the current solution to the linear problem.

Definition at line 236 of file BelosPCPGIter.hpp.

template<class ScalarType , class MV , class OP >

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

inlinevirtual

Get a constant reference to the linear problem.

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

Definition at line 248 of file BelosPCPGIter.hpp.

template<class ScalarType , class MV , class OP >

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

inlinevirtual

Get the maximum number of blocks used by the iterative solver in solving this linear problem.

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

Definition at line 251 of file BelosPCPGIter.hpp.

template<class ScalarType , class MV , class OP >

int Belos::PCPGIter< ScalarType, MV, OP >::getNumRecycledBlocks ( ) const

inline

Get the maximum number of recycled blocks used by the iterative solver in solving this linear problem.

Definition at line 254 of file BelosPCPGIter.hpp.

template<class ScalarType , class MV , class OP >

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

inlinevirtual

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

Set the blocksize.

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

Definition at line 259 of file BelosPCPGIter.hpp.

template<class ScalarType , class MV , class OP >

void Belos::PCPGIter< ScalarType, MV, OP >::setSize

(

int

savedBlocks

)

Set the maximum number of saved or recycled blocks used by the iterative solver.

Definition at line 390 of file BelosPCPGIter.hpp.

template<class ScalarType , class MV , class OP >

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

inlinevirtual

States whether the solver has been initialized or not.

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

Definition at line 268 of file BelosPCPGIter.hpp.

template<class ScalarType , class MV , class OP >

void Belos::PCPGIter< ScalarType, MV, OP >::resetState

(

)

tell the Iterator to "reset" itself; delete and rebuild the seed space.

Definition at line 410 of file BelosPCPGIter.hpp.

template<class ScalarType , class MV , class OP >

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

private

Method for initalizing the state storage needed by PCPG.

Definition at line 422 of file BelosPCPGIter.hpp.

Member Data Documentation

template<class ScalarType , class MV , class OP >

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

private

Definition at line 286 of file BelosPCPGIter.hpp.

template<class ScalarType , class MV , class OP >

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

private

Definition at line 287 of file BelosPCPGIter.hpp.

template<class ScalarType , class MV , class OP >

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

private

Definition at line 288 of file BelosPCPGIter.hpp.

template<class ScalarType , class MV , class OP >

const Teuchos::RCP<OrthoManager<ScalarType,MV> > Belos::PCPGIter< ScalarType, MV, OP >::ortho_

private

Definition at line 289 of file BelosPCPGIter.hpp.

template<class ScalarType , class MV , class OP >

int Belos::PCPGIter< ScalarType, MV, OP >::savedBlocks_

private

Definition at line 294 of file BelosPCPGIter.hpp.

template<class ScalarType , class MV , class OP >

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

private

Definition at line 302 of file BelosPCPGIter.hpp.

template<class ScalarType , class MV , class OP >

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

private

Definition at line 307 of file BelosPCPGIter.hpp.

template<class ScalarType , class MV , class OP >

bool Belos::PCPGIter< ScalarType, MV, OP >::keepDiagonal_

private

Definition at line 310 of file BelosPCPGIter.hpp.

template<class ScalarType , class MV , class OP >

bool Belos::PCPGIter< ScalarType, MV, OP >::initDiagonal_

private

Definition at line 314 of file BelosPCPGIter.hpp.

template<class ScalarType , class MV , class OP >

int Belos::PCPGIter< ScalarType, MV, OP >::curDim_

private

Definition at line 317 of file BelosPCPGIter.hpp.

template<class ScalarType , class MV , class OP >

int Belos::PCPGIter< ScalarType, MV, OP >::prevUdim_

private

Definition at line 320 of file BelosPCPGIter.hpp.

template<class ScalarType , class MV , class OP >

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

private

Definition at line 323 of file BelosPCPGIter.hpp.

template<class ScalarType , class MV , class OP >

Teuchos::RCP<MV> Belos::PCPGIter< ScalarType, MV, OP >::R_

private

Definition at line 328 of file BelosPCPGIter.hpp.

template<class ScalarType , class MV , class OP >

Teuchos::RCP<MV> Belos::PCPGIter< ScalarType, MV, OP >::Z_

private

Definition at line 331 of file BelosPCPGIter.hpp.

template<class ScalarType , class MV , class OP >

Teuchos::RCP<MV> Belos::PCPGIter< ScalarType, MV, OP >::P_

private

Definition at line 334 of file BelosPCPGIter.hpp.

template<class ScalarType , class MV , class OP >

Teuchos::RCP<MV> Belos::PCPGIter< ScalarType, MV, OP >::AP_

private

Definition at line 337 of file BelosPCPGIter.hpp.

template<class ScalarType , class MV , class OP >

Teuchos::RCP<MV> Belos::PCPGIter< ScalarType, MV, OP >::U_

private

Definition at line 340 of file BelosPCPGIter.hpp.

template<class ScalarType , class MV , class OP >

Teuchos::RCP<MV> Belos::PCPGIter< ScalarType, MV, OP >::C_

private

Definition at line 343 of file BelosPCPGIter.hpp.

template<class ScalarType , class MV , class OP >

Teuchos::RCP<Teuchos::SerialDenseMatrix<int,ScalarType> > Belos::PCPGIter< ScalarType, MV, OP >::D_

private

Definition at line 347 of file BelosPCPGIter.hpp.

---

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

• BelosPCPGIter.hpp