Amesos_Dscpack Class Reference

Amesos_Dscpack: An object-oriented wrapper for Dscpack. More...

#include <Amesos_Dscpack.h>

Inheritance diagram for Amesos_Dscpack:

[legend]Collaboration diagram for Amesos_Dscpack:[legend]List of all members.

Public Member Functions
Constructor methods
	Amesos_Dscpack (const Epetra_LinearProblem &LinearProblem)
	Amesos_Dscpack Constructor.
	~Amesos_Dscpack (void)
	Amesos_Dscpack Destructor.
Mathematical functions.
int	SymbolicFactorization ()
	Performs SymbolicFactorization on the matrix A.
int	NumericFactorization ()
	Performs NumericFactorization on the matrix A.
int	Solve ()
	Solves A X = B (or AT x = B).
Additional methods required to support the Epetra_Operator interface.
const Epetra_LinearProblem *	GetProblem () const
	Get a pointer to the Problem.
bool	MatrixShapeOK () const
	Returns true if DSCPACK can handle this matrix shape.
int	SetUseTranspose (bool UseTranspose)
	If set true, X will be set to the solution of AT X = B (not A X = B).
bool	UseTranspose () const
	Returns the current UseTranspose setting.
const Epetra_Comm &	Comm () const
	Returns a pointer to the Epetra_Comm communicator associated with this matrix.
int	SetParameters (Teuchos::ParameterList &ParameterList)
	Updates internal variables.
Protected Attributes
bool	SymbolicFactorizationOK_
bool	NumericFactorizationOK_
Epetra_CrsGraph *	DscGraph_
bool	UseTranspose_
const Epetra_LinearProblem *	Problem_
DSC_Solver	MyDSCObject
MPI_Comm	MPIC
bool	FirstCallToSolve_
bool	A_and_LU_built
int *	GlobalStructNewColNum
int *	GlobalStructNewNum
int *	GlobalStructOwner
int *	LocalStructOldNum
int	MyDscRank
int	DscNumProcs
int	NumLocalCols
int	NumGlobalCols
int	NumLocalStructs
int	NumLocalNonz

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Detailed Description

Amesos_Dscpack: An object-oriented wrapper for Dscpack.

Amesos_Dscpack will solve a linear systems of equations: A X = B using Epetra objects and the Dscpack solver library, where A is an Epetra_RowMatrix and X and B are Epetra_MultiVector objects.

Dscpack execution can be tuned through a variety of parameters. Amesos_Dscpack.h allows control of these parameters through the following named parameters, ignoring parameters with names that it does not recognize. Where possible, the parameters are common to all direct solvers (although some may ignore them). However, some parameters, in particular tuning parameters, are unique to each solver.

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Constructor & Destructor Documentation

Amesos_Dscpack::Amesos_Dscpack (  const Epetra_LinearProblem &  LinearProblem  )

Amesos_Dscpack Constructor. Creates an Amesos_Dscpack instance, using an Epetra_LinearProblem, passing in an already-defined Epetra_LinearProblem object. Note: The operator in LinearProblem must be an Epetra_RowMatrix.

Amesos_Dscpack::~Amesos_Dscpack (  void   )

Amesos_Dscpack Destructor. Completely deletes an Amesos_Dscpack object.

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Member Function Documentation

bool Amesos_Dscpack::MatrixShapeOK (   )  const [virtual]

Returns true if DSCPACK can handle this matrix shape. Returns true if the matrix shape is one that DSCPACK can handle. DSCPACK only works with symetric matrices. Implements Amesos_BaseSolver.

int Amesos_Dscpack::NumericFactorization (   )  [virtual]

Performs NumericFactorization on the matrix A. In addition to performing numeric factorization (and symbolic factorization if necessary) on the matrix A, the call to NumericFactorization() implies that no change will be made to the underlying matrix without a subsequent call to NumericFactorization(). preconditions: GetProblem().GetOperator() != 0 (return -1) MatrixShapeOk(GetProblem().GetOperator()) == true (return -6) The non-zero structure of the matrix should not have changed since the last call to SymbolicFactorization(). The distribution of the matrix should not have changed since the last call to SymbolicFactorization() postconditions: Numeric Factorization will be performed (or marked to be performed) allowing Solve() to be performed correctly despite a potential change in in the matrix values (though not in the non-zero structure). Returns: Integer error code, set to 0 if successful. Implements Amesos_BaseSolver.

int Amesos_Dscpack::SetParameters (  Teuchos::ParameterList &  ParameterList  )  [virtual]

Updates internal variables. <br >Preconditions: None. <br >Postconditions: Internal variables controlling the factorization and solve will be updated and take effect on all subsequent calls to NumericFactorization() and Solve(). All parameters whose value are to differ from the default values must be included in ParameterList. Parameters not specified in ParameterList revert to their default values. Returns: Integer error code, set to 0 if successful. Implements Amesos_BaseSolver.

int Amesos_Dscpack::SetUseTranspose (  bool  UseTranspose  )  [inline, virtual]

If set true, X will be set to the solution of AT X = B (not A X = B). If the implementation of this interface does not support transpose use, this method should return a value of -1. <br >Preconditions: SetTranspose() should be called prior to the call to SymbolicFactorization() If NumericFactorization() or Solve() is called after SetTranspose() without an intervening call to SymbolicFactorization() the result is implementation dependent. <br >Postconditions: The next factorization and solve will be performed with the new value of UseTranspose. Parameters: In  UseTranspose -If true, solve AT X = B, otherwise solve A X = B. Returns: Integer error code, set to 0 if successful. Set to -1 if this implementation does not support transpose. Implements Amesos_BaseSolver.

int Amesos_Dscpack::Solve (   )  [virtual]

Solves A X = B (or AT x = B). preconditions: GetProblem().GetOperator() != 0 (return -1) MatrixShapeOk(GetProblem().GetOperator()) == true (return -6) GetProblem()->CheckInput (see Epetra_LinearProblem::CheckInput() for return values) The non-zero structure of the matrix should not have changed since the last call to SymbolicFactorization(). The distribution of the matrix should not have changed since the last call to SymbolicFactorization() The matrix should not have changed since the last call to NumericFactorization(). postconditions: X will be set such that A X = B (or AT X = B), within the limits of the accuracy of the underlying solver. Returns: Integer error code, set to 0 if successful. Implements Amesos_BaseSolver.

int Amesos_Dscpack::SymbolicFactorization (   )  [virtual]

Performs SymbolicFactorization on the matrix A. In addition to performing symbolic factorization on the matrix A, the call to SymbolicFactorization() implies that no change will be made to the non-zero structure of the underlying matrix without a subsequent call to SymbolicFactorization(). preconditions: GetProblem().GetOperator() != 0 (return -1) MatrixShapeOk(GetProblem().GetOperator()) == true (return -6) postconditions: Symbolic Factorization will be performed (or marked to be performed) allowing NumericFactorization() and Solve() to be called. Returns: Integer error code, set to 0 if successful. Implements Amesos_BaseSolver.

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

• Amesos_Dscpack.h
• Amesos_Dscpack.cpp

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