Convergence test using the implicit residual norm(s), with an explicit residual norm(s) check for loss of accuracy if necessary. More...

#include <BelosStatusTestImpResNorm.hpp>

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

[legend]

Public Types
typedef Teuchos::ScalarTraits < ScalarType >::magnitudeType	MagnitudeType
	The type of the magnitude (absolute value) of a ScalarType. More...

Public Types inherited from Belos::StatusTestResNorm< ScalarType, MV, OP >
typedef Teuchos::ScalarTraits < ScalarType >	SCT

typedef SCT::magnitudeType	MagnitudeType

typedef MultiVecTraits < ScalarType, MV >	MVT

Public Member Functions
Constructors and destructor.
	StatusTestImpResNorm (MagnitudeType Tolerance, int quorum=-1, bool showMaxResNormOnly=false)
	Constructor. More...

virtual	~StatusTestImpResNorm ()
	Destructor (virtual for memory safety). More...

Form and parameter definition methods.
int	defineResForm (NormType TypeOfNorm)
	Define form of the residual, its norm and optional weighting vector. More...

int	defineScaleForm (ScaleType TypeOfScaling, NormType TypeOfNorm, MagnitudeType ScaleValue=Teuchos::ScalarTraits< MagnitudeType >::one())
	Define form of the scaling, its norm, its optional weighting vector, or, alternatively, define an explicit value. More...

int	setTolerance (MagnitudeType tolerance)
	Set the value of the tolerance. More...

int	setQuorum (int quorum)
	Sets the number of residuals that must pass the convergence test before Passed is returned. More...

int	setShowMaxResNormOnly (bool showMaxResNormOnly)
	Set whether the only maximum residual norm is displayed when the print() method is called. More...

Status methods
StatusType	checkStatus (Iteration< ScalarType, MV, OP > *iSolver)
	Check convergence status: Passed, Failed, or Undefined. More...

StatusType	getStatus () const
	Return the result of the most recent CheckStatus call. More...

Reset methods
void	reset ()
	Resets the internal configuration to the initial state. More...

Print methods
void	print (std::ostream &os, int indent=0) const
	Output formatted description of stopping test to output stream. More...

void	printStatus (std::ostream &os, StatusType type) const
	Print message for each status specific to this stopping test. More...

Methods to access data members.
Teuchos::RCP< MV >	getSolution ()
	Returns the current solution estimate that was computed for the most recent residual test. More...

int	getQuorum () const
	Returns the number of residuals that must pass the convergence test before Passed is returned. More...

bool	getShowMaxResNormOnly ()
	Returns whether the only maximum residual norm is displayed when the print() method is called. More...

std::vector< int >	convIndices ()
	Returns the vector containing the indices of the residuals that passed the test. More...

MagnitudeType	getTolerance () const
	"Original" convergence tolerance $\tau$ as set by user. More...

MagnitudeType	getCurrTolerance () const
	Current convergence tolerance; may be changed to prevent loss of accuracy. More...

const std::vector < MagnitudeType > *	getTestValue () const
	Returns the test value, $\frac{\\|r\\|}{\sigma}$ , computed in most recent call to CheckStatus. More...

const std::vector < MagnitudeType > *	getResNormValue () const
	Returns the residual norm value, $\\|r\\|$ , computed in most recent call to CheckStatus. More...

const std::vector < MagnitudeType > *	getScaledNormValue () const
	Returns the scaled norm value, $\sigma$ . More...

bool	getLOADetected () const
	Returns a boolean indicating a loss of accuracy has been detected in computing the residual. More...

Misc.
StatusType	firstCallCheckStatusSetup (Iteration< ScalarType, MV, OP > *iSolver)
	Call to setup initial scaling vector. More...

Overridden from Teuchos::Describable
std::string	description () const
	Method to return description of the maximum iteration status test. More...

Public Member Functions inherited from Belos::StatusTestResNorm< ScalarType, MV, OP >
virtual int	setTolerance (MagnitudeType tolerance)=0
	Set the value of the tolerance. More...

virtual int	defineScaleForm (ScaleType TypeOfScaling, NormType TypeOfNorm, MagnitudeType ScaleValue=Teuchos::ScalarTraits< MagnitudeType >::one())=0
	Define the form of the scaling for the residual. More...

Public Member Functions inherited from Belos::StatusTest< ScalarType, MV, OP >
	StatusTest ()
	Constructor. More...

virtual	~StatusTest ()
	Destructor. More...

Public Member Functions inherited from Teuchos::Describable
virtual void	describe (FancyOStream &out, const EVerbosityLevel verbLevel=verbLevel_default) const

void	describe (std::ostream &out, const EVerbosityLevel verbLevel=verbLevel_default) const

virtual	~Describable ()

	LabeledObject ()

virtual	~LabeledObject ()

virtual void	setObjectLabel (const std::string &objectLabel)

virtual std::string	getObjectLabel () const

DescribableStreamManipulatorState	describe (const Describable &describable, const EVerbosityLevel verbLevel=Describable::verbLevel_default)

std::ostream &	operator<< (std::ostream &os, const DescribableStreamManipulatorState &d)

Additional Inherited Members
Static Public Attributes inherited from Teuchos::Describable
static const EVerbosityLevel	verbLevel_default

Detailed Description

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

Convergence test using the implicit residual norm(s), with an explicit residual norm(s) check for loss of accuracy if necessary.

This test passes when a quorum of residual vectors (for all right-hand sides) passes a residual norm test. For residual vector $r_i$ , the form of the test is $\|r_i\| / \sigma_i \le \tau$ , where $\tau$ is the convergence tolerance set in the constructor or by setTolerance(). The default quorum consists of all the vectors, but you can set the number of vectors that must pass before the whole test passes, either by the constructor argument or by calling setQuorum().

The default residual vector norm (the norm used in the numerator of the test, and applied to the current residual vectors) is the 2-norm, but you can change the norm type (1-norm, 2-norm, or infinity norm) using defineResForm(). The default scaling factor $\sigma_i$ for residual vector i is the 2-norm of the initial residual vector, but you can change this using defineScaleForm(). The norm used for the scaling factors may be different than the norm used for the current residual vectors. Furthermore, each residual vector may use a different scaling factor $\sigma_i$ .

This test starts by using the "implicit" residual norm, otherwise called the "recursive" or "native" residual norm. It comes from the iterative method's projected problem, unlike the "explicit" residual norm, which comes from explicitly computing $R = B - A * X$ . Once the implicit residual norm reaches the convergence tolerance, this test then checks the explicit residual norm to make sure that it has reached the convergence tolerance as well.

We say that there is a "potential loss of accuracy" when we first detect that the implicit residual norm(s) have met the desired original convergence tolerance, but the explicit residual norm(s) have not. We don't actually call this a "loss of accuracy" (in the sense of getLOADetected() returning true) unless we tried to remedy this situation, but couldn't fix it. Upon detecting a potential loss of accuracy, this test tells the solver to "iterate a few more steps" by making the "current" residual tolerance (the value of getCurrTolerance()) smaller, and forcing the implicit residual norm(s) to meet the current tolerance before moving on to test the explicit norm(s). If that doesn't work, this test declares a loss of accuracy.

Definition at line 72 of file BelosStatusTestImpResNorm.hpp.

Member Typedef Documentation

template<class ScalarType , class MV , class OP >

typedef Teuchos::ScalarTraits<ScalarType>::magnitudeType Belos::StatusTestImpResNorm< ScalarType, MV, OP >::MagnitudeType

The type of the magnitude (absolute value) of a ScalarType.

Definition at line 75 of file BelosStatusTestImpResNorm.hpp.

Constructor & Destructor Documentation

template<class ScalarType , class MV , class OP >

Belos::StatusTestImpResNorm< ScalarType, MV, OP >::StatusTestImpResNorm	(	MagnitudeType	Tolerance,
		int	quorum = `-1`,
		bool	showMaxResNormOnly = `false`
	)

Constructor.

Parameters

Tolerance	[in] Convergence tolerance $\tau$ .
quorum	[in] The number of vectors in the problem that must pass the convergence criteria before this StatusTest passes. -1 means that all residuals must pass.
showMaxResNormOnly	[in] Whether only the maximum residual norm (of all vectors) is displayed when the print() method is called.

Definition at line 389 of file BelosStatusTestImpResNorm.hpp.

template<class ScalarType , class MV , class OP >

Belos::StatusTestImpResNorm< ScalarType, MV, OP >::~StatusTestImpResNorm ( )

virtual

Destructor (virtual for memory safety).

Definition at line 413 of file BelosStatusTestImpResNorm.hpp.

Member Function Documentation

template<class ScalarType , class MV , class OP >

int Belos::StatusTestImpResNorm< ScalarType, MV, OP >::defineResForm ( NormType TypeOfNorm )

Define form of the residual, its norm and optional weighting vector.

This method defines the form of $\|r\|$ . We specify:

The norm to be used on the residual (this may be different than the norm used in defineScaleForm()).

Definition at line 432 of file BelosStatusTestImpResNorm.hpp.

template<class ScalarType , class MV , class OP >

int Belos::StatusTestImpResNorm< ScalarType, MV, OP >::defineScaleForm	(	ScaleType	TypeOfScaling,
		NormType	TypeOfNorm,
		MagnitudeType	ScaleValue = `Teuchos::ScalarTraits<MagnitudeType>::one()`
	)

Define form of the scaling, its norm, its optional weighting vector, or, alternatively, define an explicit value.

This method defines the form of how the residual is scaled (if at all). It operates in two modes:

User-provided scaling value:
- Set argument TypeOfScaling to UserProvided.
- Set ScaleValue to a non-zero value that the residual norm will be divided by.
- TypeOfNorm argument will be ignored.
- Sample use: Define ScaleValue = $\|A\|_{\infty}$ where is the matrix of the linear problem.
Use a supported Scaling Form:
- Define TypeOfScaling to be the norm of the right hand side, the initial residual vector, or to none.
- Define norm to be used on the scaling vector (this may be different than the norm used in DefineResForm()).

Definition at line 444 of file BelosStatusTestImpResNorm.hpp.

template<class ScalarType , class MV , class OP >

int Belos::StatusTestImpResNorm< ScalarType, MV, OP >::setTolerance ( MagnitudeType tolerance )

inline

Set the value of the tolerance.

We allow the tolerance to be reset for cases where, in the process of testing the residual, we find that the initial tolerance was too tight or too lax.

Definition at line 147 of file BelosStatusTestImpResNorm.hpp.

template<class ScalarType , class MV , class OP >

int Belos::StatusTestImpResNorm< ScalarType, MV, OP >::setQuorum ( int quorum )

inlinevirtual

Sets the number of residuals that must pass the convergence test before Passed is returned.

Note: If quorum=-1 then all residuals must pass the convergence test before Passed is returned.

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

Definition at line 154 of file BelosStatusTestImpResNorm.hpp.

template<class ScalarType , class MV , class OP >

int Belos::StatusTestImpResNorm< ScalarType, MV, OP >::setShowMaxResNormOnly ( bool showMaxResNormOnly )

inlinevirtual

Set whether the only maximum residual norm is displayed when the print() method is called.

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

Definition at line 160 of file BelosStatusTestImpResNorm.hpp.

template<class ScalarType , class MV , class OP >

StatusType Belos::StatusTestImpResNorm< ScalarType, MV, OP >::checkStatus ( Iteration< ScalarType, MV, OP > * iSolver )

virtual

Check convergence status: Passed, Failed, or Undefined.

This method checks to see if the convergence criteria are met. Depending on how the residual test is constructed this method will return the appropriate status type.

Returns: StatusType: Passed, Failed, or Undefined.

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

Definition at line 460 of file BelosStatusTestImpResNorm.hpp.

template<class ScalarType , class MV , class OP >

StatusType Belos::StatusTestImpResNorm< ScalarType, MV, OP >::getStatus ( ) const

inlinevirtual

Return the result of the most recent CheckStatus call.

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

Definition at line 179 of file BelosStatusTestImpResNorm.hpp.

template<class ScalarType , class MV , class OP >

void Belos::StatusTestImpResNorm< ScalarType, MV, OP >::reset ( )

virtual

Resets the internal configuration to the initial state.

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

Definition at line 417 of file BelosStatusTestImpResNorm.hpp.

template<class ScalarType , class MV , class OP >

void Belos::StatusTestImpResNorm< ScalarType, MV, OP >::print	(	std::ostream &	os,
		int	indent = `0`
	)		const

virtual

Output formatted description of stopping test to output stream.

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

Definition at line 720 of file BelosStatusTestImpResNorm.hpp.

template<class ScalarType , class MV , class OP >

void Belos::StatusTestImpResNorm< ScalarType, MV, OP >::printStatus	(	std::ostream &	os,
		StatusType	type
	)		const

virtual

Print message for each status specific to this stopping test.

Reimplemented from Belos::StatusTest< ScalarType, MV, OP >.

Definition at line 752 of file BelosStatusTestImpResNorm.hpp.

template<class ScalarType , class MV , class OP >

Teuchos::RCP<MV> Belos::StatusTestImpResNorm< ScalarType, MV, OP >::getSolution ( )

inlinevirtual

Returns the current solution estimate that was computed for the most recent residual test.

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

Definition at line 204 of file BelosStatusTestImpResNorm.hpp.

template<class ScalarType , class MV , class OP >

int Belos::StatusTestImpResNorm< ScalarType, MV, OP >::getQuorum ( ) const

inlinevirtual

Returns the number of residuals that must pass the convergence test before Passed is returned.

Note: If quorum=-1 then all residuals must pass the convergence test before Passed is returned.

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

Definition at line 208 of file BelosStatusTestImpResNorm.hpp.

template<class ScalarType , class MV , class OP >

bool Belos::StatusTestImpResNorm< ScalarType, MV, OP >::getShowMaxResNormOnly ( )

inlinevirtual

Returns whether the only maximum residual norm is displayed when the print() method is called.

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

Definition at line 211 of file BelosStatusTestImpResNorm.hpp.

template<class ScalarType , class MV , class OP >

std::vector<int> Belos::StatusTestImpResNorm< ScalarType, MV, OP >::convIndices ( )

inlinevirtual

Returns the vector containing the indices of the residuals that passed the test.

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

Definition at line 214 of file BelosStatusTestImpResNorm.hpp.

template<class ScalarType , class MV , class OP >

MagnitudeType Belos::StatusTestImpResNorm< ScalarType, MV, OP >::getTolerance ( ) const

inlinevirtual

"Original" convergence tolerance $\tau$ as set by user.

This value is the convergence tolerance as set by the user in the constructor, or by the setTolerance() method. See this class' main documentation and the documentation of getCurrTolerance() for an explanation of the difference between the "original" and "current" tolerances.

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

Definition at line 223 of file BelosStatusTestImpResNorm.hpp.

template<class ScalarType , class MV , class OP >

MagnitudeType Belos::StatusTestImpResNorm< ScalarType, MV, OP >::getCurrTolerance ( ) const

inline

Current convergence tolerance; may be changed to prevent loss of accuracy.

The difference between "original" tolerance (the value of getTolerance()) and "current" tolerance (the value of this method) relates to the idea of "loss of accuracy." See this class' main documentation for details. We do not allow users to set the "current" tolerance.

Definition at line 234 of file BelosStatusTestImpResNorm.hpp.

template<class ScalarType , class MV , class OP >

const std::vector<MagnitudeType>* Belos::StatusTestImpResNorm< ScalarType, MV, OP >::getTestValue ( ) const

inlinevirtual

Returns the test value, $\frac{\|r\|}{\sigma}$ , computed in most recent call to CheckStatus.

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

Definition at line 239 of file BelosStatusTestImpResNorm.hpp.

template<class ScalarType , class MV , class OP >

const std::vector<MagnitudeType>* Belos::StatusTestImpResNorm< ScalarType, MV, OP >::getResNormValue ( ) const

inline

Returns the residual norm value, $\|r\|$ , computed in most recent call to CheckStatus.

Definition at line 242 of file BelosStatusTestImpResNorm.hpp.

template<class ScalarType , class MV , class OP >

const std::vector<MagnitudeType>* Belos::StatusTestImpResNorm< ScalarType, MV, OP >::getScaledNormValue ( ) const

inline

Returns the scaled norm value, $\sigma$ .

Definition at line 245 of file BelosStatusTestImpResNorm.hpp.

template<class ScalarType , class MV , class OP >

bool Belos::StatusTestImpResNorm< ScalarType, MV, OP >::getLOADetected ( ) const

inlinevirtual

Returns a boolean indicating a loss of accuracy has been detected in computing the residual.

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

Definition at line 248 of file BelosStatusTestImpResNorm.hpp.

template<class ScalarType , class MV , class OP >

StatusType Belos::StatusTestImpResNorm< ScalarType, MV, OP >::firstCallCheckStatusSetup ( Iteration< ScalarType, MV, OP > * iSolver )

Call to setup initial scaling vector.

After this function is called getScaledNormValue() can be called to get the scaling vector.

Definition at line 776 of file BelosStatusTestImpResNorm.hpp.

template<class ScalarType , class MV , class OP >

std::string Belos::StatusTestImpResNorm< ScalarType, MV, OP >::description ( ) const

inlinevirtual

Method to return description of the maximum iteration status test.

Reimplemented from Teuchos::Describable.

Definition at line 267 of file BelosStatusTestImpResNorm.hpp.

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

BelosStatusTestImpResNorm.hpp

Public Types

Public Member Functions

Additional Inherited Members

Detailed Description

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

Member Typedef Documentation

Constructor & Destructor Documentation

Member Function Documentation

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