Ifpack_LocalFilter a class for light-weight extraction of the submatrix corresponding to local rows and columns. More...

#include <Ifpack_LocalFilter.h>

Inheritance diagram for Ifpack_LocalFilter:

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Public Member Functions
int	SetOwnership (bool)
	Sets ownership. More...

int	SetUseTranspose (bool UseTranspose_in)
	Sets use transpose (not implemented). More...

bool	UseTranspose () const
	Returns the current UseTranspose setting. More...

bool	HasNormInf () const
	Returns true if the this object can provide an approximate Inf-norm, false otherwise. More...

const Epetra_Comm &	Comm () const
	Returns a pointer to the Epetra_Comm communicator associated with this operator. More...

const Epetra_Map &	OperatorDomainMap () const
	Returns the Epetra_Map object associated with the domain of this operator. More...

const Epetra_Map &	OperatorRangeMap () const
	Returns the Epetra_Map object associated with the range of this operator. More...

const Epetra_BlockMap &	Map () const

const char *	Label () const

Private Attributes
Teuchos::RefCountPtr< const Epetra_RowMatrix >	Matrix_
	Pointer to the matrix to be preconditioned. More...

Teuchos::RefCountPtr < Epetra_SerialComm >	SerialComm_
	Communicator containing this process only. More...

Teuchos::RefCountPtr< Epetra_Map >	Map_
	Map based on SerialComm_, containing the local rows only. More...

int	NumRows_
	Number of rows in the local matrix. More...

int	NumNonzeros_
	Number of nonzeros in the local matrix. More...

int	MaxNumEntries_
	Maximum number of nonzero entries in a row for the filtered matrix. More...

int	MaxNumEntriesA_
	Maximum number of nonzero entries in a row for Matrix_. More...

std::vector< int >	NumEntries_
	NumEntries_[i] contains the nonzero entries in row `i'. More...

std::vector< int >	Indices_
	Used in ExtractMyRowCopy, to avoid allocation each time. More...

std::vector< double >	Values_
	Used in ExtractMyRowCopy, to avoid allocation each time. More...

bool	UseTranspose_
	If true, the tranpose of the local matrix will be used. More...

char	Label_ [80]
	Label for `this` object. More...

Teuchos::RefCountPtr < Epetra_Vector >	Diagonal_

	Ifpack_LocalFilter (const Teuchos::RefCountPtr< const Epetra_RowMatrix > &Matrix)
	Constructor. More...

virtual	~Ifpack_LocalFilter ()
	Destructor. More...

virtual int	NumMyRowEntries (int MyRow, int &NumEntries) const
	Returns the number of nonzero entries in MyRow. More...

virtual int	MaxNumEntries () const
	Returns the maximum of NumMyRowEntries() over all rows. More...

virtual int	ExtractMyRowCopy (int MyRow, int Length, int &NumEntries, double Values, int Indices) const
	Returns a copy of the specified local row in user-provided arrays. More...

virtual int	ExtractDiagonalCopy (Epetra_Vector &Diagonal) const
	Returns a copy of the main diagonal in a user-provided vector. More...

virtual int	Multiply (bool TransA, const Epetra_MultiVector &X, Epetra_MultiVector &Y) const
	Returns the result of a Epetra_RowMatrix multiplied by a Epetra_MultiVector X in Y. More...

virtual int	Solve (bool, bool, bool, const Epetra_MultiVector &, Epetra_MultiVector &) const
	Returns result of a local-only solve using a triangular Epetra_RowMatrix with Epetra_MultiVectors X and Y (NOT IMPLEMENTED). More...

virtual int	Apply (const Epetra_MultiVector &X, Epetra_MultiVector &Y) const

virtual int	ApplyInverse (const Epetra_MultiVector &X, Epetra_MultiVector &Y) const

virtual int	InvRowSums (Epetra_Vector &) const
	Computes the sum of absolute values of the rows of the Epetra_RowMatrix, results returned in x (NOT IMPLEMENTED). More...

virtual int	LeftScale (const Epetra_Vector &)
	Scales the Epetra_RowMatrix on the left with a Epetra_Vector x (NOT IMPLEMENTED). More...

virtual int	InvColSums (Epetra_Vector &) const
	Computes the sum of absolute values of the columns of the Epetra_RowMatrix, results returned in x (NOT IMPLEMENTED). More...

virtual int	RightScale (const Epetra_Vector &)
	Scales the Epetra_RowMatrix on the right with a Epetra_Vector x (NOT IMPLEMENTED). More...

virtual bool	Filled () const
	If FillComplete() has been called, this query returns true, otherwise it returns false. More...

virtual double	NormInf () const
	Returns the infinity norm of the global matrix. More...

virtual double	NormOne () const
	Returns the one norm of the global matrix. More...

virtual int	NumGlobalNonzeros () const
	Returns the number of nonzero entries in the global matrix. More...

virtual int	NumGlobalRows () const
	Returns the number of global matrix rows. More...

virtual int	NumGlobalCols () const
	Returns the number of global matrix columns. More...

virtual int	NumGlobalDiagonals () const
	Returns the number of global nonzero diagonal entries, based on global row/column index comparisons. More...

virtual long long	NumGlobalNonzeros64 () const
	Returns the number of nonzero entries in the global matrix. More...

virtual long long	NumGlobalRows64 () const
	Returns the number of global matrix rows. More...

virtual long long	NumGlobalCols64 () const
	Returns the number of global matrix columns. More...

virtual long long	NumGlobalDiagonals64 () const
	Returns the number of global nonzero diagonal entries, based on global row/column index comparisons. More...

virtual int	NumMyNonzeros () const
	Returns the number of nonzero entries in the calling processor's portion of the matrix. More...

virtual int	NumMyRows () const
	Returns the number of matrix rows owned by the calling processor. More...

virtual int	NumMyCols () const
	Returns the number of matrix columns owned by the calling processor. More...

virtual int	NumMyDiagonals () const
	Returns the number of local nonzero diagonal entries, based on global row/column index comparisons. More...

virtual bool	LowerTriangular () const
	If matrix is lower triangular in local index space, this query returns true, otherwise it returns false. More...

virtual bool	UpperTriangular () const
	If matrix is upper triangular in local index space, this query returns true, otherwise it returns false. More...

virtual const Epetra_Map &	RowMatrixRowMap () const
	Returns the Epetra_Map object associated with the rows of this matrix. More...

virtual const Epetra_Map &	RowMatrixColMap () const
	Returns the Epetra_Map object associated with the columns of this matrix. More...

virtual const Epetra_Import *	RowMatrixImporter () const
	Returns the Epetra_Import object that contains the import operations for distributed operations. More...

Detailed Description

Ifpack_LocalFilter a class for light-weight extraction of the submatrix corresponding to local rows and columns.

Class Ifpack_LocalFilter enables a light-weight contruction of an Epetra_RowMatrix-derived object, containing only the elements of the original, distributed matrix with local row and column ID. The local submatrix is based on a communicator containing the local process only. Each process will have its local object, corresponding to the local submatrix. Submatrices may or may not overlap.

The following instructions can be used to create "localized" matrices:

#include "Ifpack_LocalFilter.h"
...
Teuchos::RefCountPtr<Epetra_RowMatrix> A;             // fill the elements of A,
A->FillComplete();
Ifpack_LocalFilter LocalA(A);

Once created, LocalA defined, on each process, the submatrix corresponding to local rows and columns only. The creation and use of LocalA is "cheap", as the elements of the local matrix are obtained through calls to ExtractMyRowCopy on the original, distributed matrix, say A. This means that A must remain in scope every time LocalA is accessed.

A very convenient use of this class is to use Ifpack solvers to compute the LU factorizations of local blocks. If applied to a localized matrix, several Ifpack objects can operator in the same phase in a safe way, without non-required data exchange.

Author: Marzio Sala, SNL 9214

Date: Sep-04

Definition at line 104 of file Ifpack_LocalFilter.h.

Constructor & Destructor Documentation

Ifpack_LocalFilter::Ifpack_LocalFilter ( const Teuchos::RefCountPtr< const Epetra_RowMatrix > & Matrix )

Constructor.

Definition at line 53 of file Ifpack_LocalFilter.cpp.

virtual Ifpack_LocalFilter::~Ifpack_LocalFilter ( )

inlinevirtual

Destructor.

Definition at line 114 of file Ifpack_LocalFilter.h.

Member Function Documentation

virtual int Ifpack_LocalFilter::NumMyRowEntries	(	int	MyRow,
		int &	NumEntries
	)		const

inlinevirtual

Returns the number of nonzero entries in MyRow.

Parameters

MyRow	- (In) Local row.
NumEntries	- (Out) Number of nonzero values present.

Returns: Integer error code, set to 0 if successful.

MyRow	- (In) Local row to extract.
Length	- (In) Length of Values and Indices.
NumEntries	- (Out) Number of nonzero entries extracted.
Values	- (Out) Extracted values for this row.
Indices	- (Out) Extracted global column indices for the corresponding values.

TransA	-(In) If true, multiply by the transpose of matrix, otherwise just use matrix.
X	- (In) A Epetra_MultiVector of dimension NumVectors to multiply with matrix.
Y	-(Out) A Epetra_MultiVector of dimension NumVectorscontaining result.

Public Member Functions

Private Attributes

Detailed Description

Constructor & Destructor Documentation

Member Function Documentation

Member Data Documentation