Ifpack2 Templated Preconditioning Package Version 1.0
Ifpack2::DropFilter< MatrixType > Class Template Reference

Ifpack2::DropFilter: Filter based on matrix entries. More...

#include <Ifpack2_DropFilter_decl.hpp>

List of all members.

Public Member Functions

Constructor & destructor methods
 DropFilter (const Teuchos::RCP< const Tpetra::RowMatrix< Scalar, LocalOrdinal, GlobalOrdinal, Node > > &Matrix, magnitudeType DropTol)
 Constructor.
virtual ~DropFilter ()
 Destructor.
Matrix Query Methods
virtual const Teuchos::RCP
< const Teuchos::Comm< int > > & 
getComm () const
 Returns the communicator.
virtual Teuchos::RCP< Node > getNode () const
 Returns the underlying node.
virtual const Teuchos::RCP
< const Tpetra::Map
< LocalOrdinal, GlobalOrdinal,
Node > > & 
getRowMap () const
 Returns the Map that describes the row distribution in this matrix.
virtual const Teuchos::RCP
< const Tpetra::Map
< LocalOrdinal, GlobalOrdinal,
Node > > & 
getColMap () const
 Returns the Map that describes the column distribution in this matrix.
virtual const Teuchos::RCP
< const Tpetra::Map
< LocalOrdinal, GlobalOrdinal,
Node > > & 
getDomainMap () const
 Returns the Map that describes the domain distribution in this matrix.
virtual const Teuchos::RCP
< const Tpetra::Map
< LocalOrdinal, GlobalOrdinal,
Node > > & 
getRangeMap () const
 Returns the Map that describes the range distribution in this matrix.
virtual Teuchos::RCP< const
Tpetra::RowGraph< LocalOrdinal,
GlobalOrdinal, Node > > 
getGraph () const
 Returns the RowGraph associated with this matrix.
virtual global_size_t getGlobalNumRows () const
 Returns the number of global rows in this matrix.
virtual global_size_t getGlobalNumCols () const
 Returns the number of global columns in this matrix.
virtual size_t getNodeNumRows () const
 Returns the number of rows owned on the calling node.
virtual size_t getNodeNumCols () const
 Returns the number of columns needed to apply the forward operator on this node, i.e., the number of elements listed in the column map.
virtual GlobalOrdinal getIndexBase () const
 Returns the index base for global indices for this matrix.
virtual global_size_t getGlobalNumEntries () const
 Returns the global number of entries in this matrix.
virtual size_t getNodeNumEntries () const
 Returns the local number of entries in this matrix.
virtual size_t getNumEntriesInGlobalRow (GlobalOrdinal globalRow) const
 Returns the current number of entries on this node in the specified global row.
virtual size_t getNumEntriesInLocalRow (LocalOrdinal localRow) const
 Returns the current number of entries on this node in the specified local row.
virtual global_size_t getGlobalNumDiags () const
 Returns the number of global diagonal entries, based on global row/column index comparisons.
virtual size_t getNodeNumDiags () const
 Returns the number of local diagonal entries, based on global row/column index comparisons.
virtual size_t getGlobalMaxNumRowEntries () const
 Returns the maximum number of entries across all rows/columns on all nodes.
virtual size_t getNodeMaxNumRowEntries () const
 Returns the maximum number of entries across all rows/columns on this node.
virtual bool hasColMap () const
 Indicates whether this matrix has a well-defined column map.
virtual bool isLowerTriangular () const
 Indicates whether this matrix is lower triangular.
virtual bool isUpperTriangular () const
 Indicates whether this matrix is upper triangular.
virtual bool isLocallyIndexed () const
 If matrix indices are in the local range, this function returns true. Otherwise, this function returns false. */.
virtual bool isGloballyIndexed () const
 If matrix indices are in the global range, this function returns true. Otherwise, this function returns false. */.
virtual bool isFillComplete () const
 Returns true if fillComplete() has been called.
virtual bool supportsRowViews () const
 Returns true if RowViews are supported.
Extraction Methods
virtual void getGlobalRowCopy (GlobalOrdinal GlobalRow, const Teuchos::ArrayView< GlobalOrdinal > &Indices, const Teuchos::ArrayView< Scalar > &Values, size_t &NumEntries) const
 Extract a list of entries in a specified global row of this matrix. Put into pre-allocated storage.
virtual void getLocalRowCopy (LocalOrdinal DropRow, const Teuchos::ArrayView< LocalOrdinal > &Indices, const Teuchos::ArrayView< Scalar > &Values, size_t &NumEntries) const
 Extract a list of entries in a specified local row of the graph. Put into storage allocated by calling routine.
virtual void getGlobalRowView (GlobalOrdinal GlobalRow, Teuchos::ArrayView< const GlobalOrdinal > &indices, Teuchos::ArrayView< const Scalar > &values) const
 Extract a const, non-persisting view of global indices in a specified row of the matrix.
virtual void getLocalRowView (LocalOrdinal DropRow, Teuchos::ArrayView< const LocalOrdinal > &indices, Teuchos::ArrayView< const Scalar > &values) const
 Extract a const, non-persisting view of local indices in a specified row of the matrix.
virtual void getLocalDiagCopy (Tpetra::Vector< Scalar, LocalOrdinal, GlobalOrdinal, Node > &diag) const
 Get a copy of the diagonal entries owned by this node, with local row indices.
Mathematical Methods
virtual void leftScale (const Tpetra::Vector< Scalar, LocalOrdinal, GlobalOrdinal, Node > &x)
 Scales the RowMatrix on the left with the Vector x.
virtual void rightScale (const Tpetra::Vector< Scalar, LocalOrdinal, GlobalOrdinal, Node > &x)
 Scales the RowMatrix on the right with the Vector x.
virtual Teuchos::ScalarTraits
< Scalar >::magnitudeType 
getFrobeniusNorm () const
 Returns the Frobenius norm of the matrix.
virtual void apply (const Tpetra::MultiVector< Scalar, LocalOrdinal, GlobalOrdinal, Node > &X, Tpetra::MultiVector< Scalar, LocalOrdinal, GlobalOrdinal, Node > &Y, Teuchos::ETransp mode=Teuchos::NO_TRANS, Scalar alpha=Teuchos::ScalarTraits< Scalar >::one(), Scalar beta=Teuchos::ScalarTraits< Scalar >::zero()) const
 Computes the operator-multivector application.
virtual bool hasTransposeApply () const
 Indicates whether this operator supports applying the adjoint operator.
Deprecated routines to be removed at some point in the future.
virtual TPETRA_DEPRECATED void getGlobalRowView (GlobalOrdinal GlobalRow, Teuchos::ArrayRCP< const GlobalOrdinal > &indices, Teuchos::ArrayRCP< const Scalar > &values) const
 Deprecated. Get a persisting const view of the entries in a specified global row of this matrix.
virtual TPETRA_DEPRECATED void getLocalRowView (LocalOrdinal DropRow, Teuchos::ArrayRCP< const LocalOrdinal > &indices, Teuchos::ArrayRCP< const Scalar > &values) const
 Deprecated. Get a persisting const view of the entries in a specified local row of this matrix.

Detailed Description

template<class MatrixType>
class Ifpack2::DropFilter< MatrixType >

Ifpack2::DropFilter: Filter based on matrix entries.

Ifpack2::DropFilter enables the dropping of all elements whose absolute value is below a specified threshold.

A typical use is as follows:

Teuchos::RCP<Tpetra::RowMatrix> A;
// first localize the matrix
Ifpack2::LocalFilter<Tpetra::RowMatrix> LocalA(A);
// drop all elements below this value
double DropTol = 1e-5;
// now create the matrix, elements below DropTol are
// not included in calls to getLocalRowCopy() and apply()
// and Apply()
Ifpack2::DropFilter<Tpetra::RowMatrix> DropA(LocalA,DropTol)

It is supposed that Ifpack2::DropFilter is used on localized matrices.

Last modified: 2-Aug-12.


Constructor & Destructor Documentation

template<class MatrixType >
Ifpack2::DropFilter< MatrixType >::DropFilter ( const Teuchos::RCP< const Tpetra::RowMatrix< Scalar, LocalOrdinal, GlobalOrdinal, Node > > &  Matrix,
magnitudeType  DropTol 
) [explicit]

Constructor.

template<class MatrixType >
Ifpack2::DropFilter< MatrixType >::~DropFilter ( ) [virtual]

Destructor.


Member Function Documentation

template<class MatrixType >
const Teuchos::RCP< const Teuchos::Comm< int > > & Ifpack2::DropFilter< MatrixType >::getComm ( ) const [virtual]

Returns the communicator.

template<class MatrixType >
Teuchos::RCP< typename MatrixType::node_type > Ifpack2::DropFilter< MatrixType >::getNode ( ) const [virtual]

Returns the underlying node.

template<class MatrixType >
const Teuchos::RCP< const Tpetra::Map< typename MatrixType::local_ordinal_type, typename MatrixType::global_ordinal_type, typename MatrixType::node_type > > & Ifpack2::DropFilter< MatrixType >::getRowMap ( ) const [virtual]

Returns the Map that describes the row distribution in this matrix.

template<class MatrixType >
const Teuchos::RCP< const Tpetra::Map< typename MatrixType::local_ordinal_type, typename MatrixType::global_ordinal_type, typename MatrixType::node_type > > & Ifpack2::DropFilter< MatrixType >::getColMap ( ) const [virtual]

Returns the Map that describes the column distribution in this matrix.

template<class MatrixType >
const Teuchos::RCP< const Tpetra::Map< typename MatrixType::local_ordinal_type, typename MatrixType::global_ordinal_type, typename MatrixType::node_type > > & Ifpack2::DropFilter< MatrixType >::getDomainMap ( ) const [virtual]

Returns the Map that describes the domain distribution in this matrix.

template<class MatrixType >
const Teuchos::RCP< const Tpetra::Map< typename MatrixType::local_ordinal_type, typename MatrixType::global_ordinal_type, typename MatrixType::node_type > > & Ifpack2::DropFilter< MatrixType >::getRangeMap ( ) const [virtual]

Returns the Map that describes the range distribution in this matrix.

template<class MatrixType >
Teuchos::RCP< const Tpetra::RowGraph< typename MatrixType::local_ordinal_type, typename MatrixType::global_ordinal_type, typename MatrixType::node_type > > Ifpack2::DropFilter< MatrixType >::getGraph ( ) const [virtual]

Returns the RowGraph associated with this matrix.

template<class MatrixType >
global_size_t Ifpack2::DropFilter< MatrixType >::getGlobalNumRows ( ) const [virtual]

Returns the number of global rows in this matrix.

template<class MatrixType >
global_size_t Ifpack2::DropFilter< MatrixType >::getGlobalNumCols ( ) const [virtual]

Returns the number of global columns in this matrix.

template<class MatrixType >
size_t Ifpack2::DropFilter< MatrixType >::getNodeNumRows ( ) const [virtual]

Returns the number of rows owned on the calling node.

template<class MatrixType >
size_t Ifpack2::DropFilter< MatrixType >::getNodeNumCols ( ) const [virtual]

Returns the number of columns needed to apply the forward operator on this node, i.e., the number of elements listed in the column map.

template<class MatrixType >
MatrixType::global_ordinal_type Ifpack2::DropFilter< MatrixType >::getIndexBase ( ) const [virtual]

Returns the index base for global indices for this matrix.

template<class MatrixType >
global_size_t Ifpack2::DropFilter< MatrixType >::getGlobalNumEntries ( ) const [virtual]

Returns the global number of entries in this matrix.

template<class MatrixType >
size_t Ifpack2::DropFilter< MatrixType >::getNodeNumEntries ( ) const [virtual]

Returns the local number of entries in this matrix.

template<class MatrixType >
size_t Ifpack2::DropFilter< MatrixType >::getNumEntriesInGlobalRow ( GlobalOrdinal  globalRow) const [virtual]

Returns the current number of entries on this node in the specified global row.

Returns Teuchos::OrdinalTraits<size_t>::invalid() if the specified global row does not belong to this graph.

template<class MatrixType >
size_t Ifpack2::DropFilter< MatrixType >::getNumEntriesInLocalRow ( LocalOrdinal  localRow) const [virtual]

Returns the current number of entries on this node in the specified local row.

Returns Teuchos::OrdinalTraits<size_t>::invalid() if the specified local row is not valid for this graph.

template<class MatrixType >
global_size_t Ifpack2::DropFilter< MatrixType >::getGlobalNumDiags ( ) const [virtual]

Returns the number of global diagonal entries, based on global row/column index comparisons.

template<class MatrixType >
size_t Ifpack2::DropFilter< MatrixType >::getNodeNumDiags ( ) const [virtual]

Returns the number of local diagonal entries, based on global row/column index comparisons.

template<class MatrixType >
size_t Ifpack2::DropFilter< MatrixType >::getGlobalMaxNumRowEntries ( ) const [virtual]

Returns the maximum number of entries across all rows/columns on all nodes.

template<class MatrixType >
size_t Ifpack2::DropFilter< MatrixType >::getNodeMaxNumRowEntries ( ) const [virtual]

Returns the maximum number of entries across all rows/columns on this node.

template<class MatrixType >
bool Ifpack2::DropFilter< MatrixType >::hasColMap ( ) const [virtual]

Indicates whether this matrix has a well-defined column map.

template<class MatrixType >
bool Ifpack2::DropFilter< MatrixType >::isLowerTriangular ( ) const [virtual]

Indicates whether this matrix is lower triangular.

template<class MatrixType >
bool Ifpack2::DropFilter< MatrixType >::isUpperTriangular ( ) const [virtual]

Indicates whether this matrix is upper triangular.

template<class MatrixType >
bool Ifpack2::DropFilter< MatrixType >::isLocallyIndexed ( ) const [virtual]

If matrix indices are in the local range, this function returns true. Otherwise, this function returns false. */.

template<class MatrixType >
bool Ifpack2::DropFilter< MatrixType >::isGloballyIndexed ( ) const [virtual]

If matrix indices are in the global range, this function returns true. Otherwise, this function returns false. */.

template<class MatrixType >
bool Ifpack2::DropFilter< MatrixType >::isFillComplete ( ) const [virtual]

Returns true if fillComplete() has been called.

template<class MatrixType >
bool Ifpack2::DropFilter< MatrixType >::supportsRowViews ( ) const [virtual]

Returns true if RowViews are supported.

template<class MatrixType >
void Ifpack2::DropFilter< MatrixType >::getGlobalRowCopy ( GlobalOrdinal  GlobalRow,
const Teuchos::ArrayView< GlobalOrdinal > &  Indices,
const Teuchos::ArrayView< Scalar > &  Values,
size_t &  NumEntries 
) const [virtual]

Extract a list of entries in a specified global row of this matrix. Put into pre-allocated storage.

Parameters:
DropRow- (In) Global row number for which indices are desired.
Indices- (Out) Global column indices corresponding to values.
Values- (Out) Matrix values.
NumEntries- (Out) Number of indices.

Note: A std::runtime_error exception is thrown if either Indices or Values is not large enough to hold the data associated with row GlobalRow. If GlobalRow does not belong to this node, then Indices and Values are unchanged and NumIndices is returned as Teuchos::OrdinalTraits<size_t>::invalid().

template<class MatrixType >
void Ifpack2::DropFilter< MatrixType >::getLocalRowCopy ( LocalOrdinal  DropRow,
const Teuchos::ArrayView< LocalOrdinal > &  Indices,
const Teuchos::ArrayView< Scalar > &  Values,
size_t &  NumEntries 
) const [virtual]

Extract a list of entries in a specified local row of the graph. Put into storage allocated by calling routine.

Parameters:
DropRow- (In) Drop row number for which indices are desired.
Indices- (Out) Drop column indices corresponding to values.
Values- (Out) Matrix values.
NumIndices- (Out) Number of indices.

Note: A std::runtime_error exception is thrown if either Indices or Values is not large enough to hold the data associated with row DropRow. If DropRow is not valid for this node, then Indices and Values are unchanged and NumIndices is returned as Teuchos::OrdinalTraits<size_t>::invalid().

template<class MatrixType >
void Ifpack2::DropFilter< MatrixType >::getGlobalRowView ( GlobalOrdinal  GlobalRow,
Teuchos::ArrayView< const GlobalOrdinal > &  indices,
Teuchos::ArrayView< const Scalar > &  values 
) const [virtual]

Extract a const, non-persisting view of global indices in a specified row of the matrix.

Parameters:
GlobalRow- (In) Global row number for which indices are desired.
Indices- (Out) Global column indices corresponding to values.
Values- (Out) Row values
Precondition:
isDroplyIndexed() == false
Postcondition:
indices.size() == getNumEntriesInGlobalRow(GlobalRow)

Note: If GlobalRow does not belong to this node, then indices is set to null.

template<class MatrixType >
void Ifpack2::DropFilter< MatrixType >::getLocalRowView ( LocalOrdinal  DropRow,
Teuchos::ArrayView< const LocalOrdinal > &  indices,
Teuchos::ArrayView< const Scalar > &  values 
) const [virtual]

Extract a const, non-persisting view of local indices in a specified row of the matrix.

Parameters:
DropRow- (In) Drop row number for which indices are desired.
Indices- (Out) Global column indices corresponding to values.
Values- (Out) Row values
Precondition:
isGloballyIndexed() == false
Postcondition:
indices.size() == getNumEntriesInDropRow(DropRow)

Note: If DropRow does not belong to this node, then indices is set to null.

template<class MatrixType >
void Ifpack2::DropFilter< MatrixType >::getLocalDiagCopy ( Tpetra::Vector< Scalar, LocalOrdinal, GlobalOrdinal, Node > &  diag) const [virtual]

Get a copy of the diagonal entries owned by this node, with local row indices.

Returns a distributed Vector object partitioned according to this matrix's row map, containing the the zero and non-zero diagonals owned by this node.

template<class MatrixType >
void Ifpack2::DropFilter< MatrixType >::leftScale ( const Tpetra::Vector< Scalar, LocalOrdinal, GlobalOrdinal, Node > &  x) [virtual]

Scales the RowMatrix on the left with the Vector x.

This matrix will be scaled such that A(i,j) = x(i)*A(i,j) where i denoes the global row number of A and j denotes the global column number of A.

Parameters:
xA vector to left scale this matrix.
template<class MatrixType >
void Ifpack2::DropFilter< MatrixType >::rightScale ( const Tpetra::Vector< Scalar, LocalOrdinal, GlobalOrdinal, Node > &  x) [virtual]

Scales the RowMatrix on the right with the Vector x.

This matrix will be scaled such that A(i,j) = x(j)*A(i,j) where i denoes the global row number of A and j denotes the global column number of A.

Parameters:
xA vector to right scale this matrix.
template<class MatrixType >
Teuchos::ScalarTraits< typename MatrixType::scalar_type >::magnitudeType Ifpack2::DropFilter< MatrixType >::getFrobeniusNorm ( ) const [virtual]

Returns the Frobenius norm of the matrix.

Computes and returns the Frobenius norm of the matrix, defined as: \( \|A\|_F = \sqrt{\sum_{i,j} \|\a_{ij}\|^2} \)

template<class MatrixType >
void Ifpack2::DropFilter< MatrixType >::apply ( const Tpetra::MultiVector< Scalar, LocalOrdinal, GlobalOrdinal, Node > &  X,
Tpetra::MultiVector< Scalar, LocalOrdinal, GlobalOrdinal, Node > &  Y,
Teuchos::ETransp  mode = Teuchos::NO_TRANS,
Scalar  alpha = Teuchos::ScalarTraits<Scalar>::one(),
Scalar  beta = Teuchos::ScalarTraits<Scalar>::zero() 
) const [virtual]

Computes the operator-multivector application.

Loosely, performs \(Y = \alpha \cdot A^{\textrm{mode}} \cdot X + \beta \cdot Y\). However, the details of operation vary according to the values of alpha and beta. Specifically

  • if beta == 0, apply() must overwrite Y, so that any values in Y (including NaNs) are ignored.
  • if alpha == 0, apply() may short-circuit the operator, so that any values in X (including NaNs) are ignored.
template<class MatrixType >
bool Ifpack2::DropFilter< MatrixType >::hasTransposeApply ( ) const [virtual]

Indicates whether this operator supports applying the adjoint operator.

template<class MatrixType >
TPETRA_DEPRECATED void Ifpack2::DropFilter< MatrixType >::getGlobalRowView ( GlobalOrdinal  GlobalRow,
Teuchos::ArrayRCP< const GlobalOrdinal > &  indices,
Teuchos::ArrayRCP< const Scalar > &  values 
) const [virtual]

Deprecated. Get a persisting const view of the entries in a specified global row of this matrix.

Parameters:
GlobalRow- (In) Global row from which to retrieve matrix entries.
Indices- (Out) Indices for the global row.
Values- (Out) Values for the global row.

Note: If GlobalRow does not belong to this node, then Indices and Values are set to Teuchos::null</t>>.

Precondition:
isDroplyIndexed()==false

template<class MatrixType >
TPETRA_DEPRECATED void Ifpack2::DropFilter< MatrixType >::getLocalRowView ( LocalOrdinal  DropRow,
Teuchos::ArrayRCP< const LocalOrdinal > &  indices,
Teuchos::ArrayRCP< const Scalar > &  values 
) const [virtual]

Deprecated. Get a persisting const view of the entries in a specified local row of this matrix.

Parameters:
DropRow- (In) Drop row from which to retrieve matrix entries.
Indices- (Out) Indices for the local row.
Values- (Out) Values for the local row.

Note: If DropRow is not valid for this node, then Indices and Values are set to Teuchos::null.

Precondition:
isGloballyIndexed()==false

The documentation for this class was generated from the following files:
 All Classes Namespaces Files Functions Variables Typedefs Enumerations Enumerator Friends