Amesos_Umfpack Class Reference

Class Amesos_Umfpack: An object-oriented wrapper for UMFPACK. More...

#include <Amesos_Umfpack.h>

Inheritance diagram for Amesos_Umfpack:

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

Public Member Functions
Constructor methods
	Amesos_Umfpack (const Epetra_LinearProblem &LinearProblem)
	Amesos_Umfpack Constructor.
	~Amesos_Umfpack (void)
	Amesos_Umfpack 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
	Returns the Epetra_LinearProblem.
bool	MatrixShapeOK () const
	Returns true if UMFPACK 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 operator.
double	GetRcond () const
	Returns an estimate of the reciprocal of the condition number.
int	SetParameters (Teuchos::ParameterList &ParameterList)
	Updates internal variables.
void	PrintTiming () const
	Prints timing information.
void	PrintStatus () const
	Prints information about the factorization and solution phases.

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Detailed Description

Class Amesos_Umfpack: An object-oriented wrapper for UMFPACK.

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

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Constructor & Destructor Documentation

Amesos_Umfpack::Amesos_Umfpack (  const Epetra_LinearProblem &  LinearProblem  )

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

Amesos_Umfpack::~Amesos_Umfpack (  void   )

Amesos_Umfpack Destructor. Completely deletes an Amesos_Umfpack object.

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Member Function Documentation

const Epetra_LinearProblem* Amesos_Umfpack::GetProblem (   )  const [inline, virtual]

Returns the Epetra_LinearProblem. Warning! Do not call return->SetOperator(...) to attempt to change the Epetra_Operator object (even if the new matrix has the same structure). This new operator matrix will be ignored! Implements Amesos_BaseSolver.

bool Amesos_Umfpack::MatrixShapeOK (   )  const [virtual]

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

int Amesos_Umfpack::NumericFactorization (   )  [virtual]

Performs NumericFactorization on the matrix A. In addition to performing numeric factorization 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(). <br >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(). (return -2 if the number of non-zeros changes) Other changes can have arbitrary consequences. The distribution of the matrix should not have changed since the last call to SymbolicFactorization() The matrix should be indexed from 0 to n-1, unless the parameter "Reindex" was set to "true" prior to the call to SymbolicFactorization(). (return -3 - if caught) The paremeter "Reindex" should not be set to "true" except on CrsMatrices. (return -4) The paremeter "Reindex" should not be set to "true" unless Amesos was built with EpetraExt, i.e. with --enable-epetraext on the configure line. (return -4) Internal errors retur -5. <br >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_Umfpack::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 subseuent 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_Umfpack::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: UseTranspose  -- (In) 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_Umfpack::Solve (   )  [virtual]

Solves A X = B (or AT x = B). <br >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(). <br >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_Umfpack::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(). <br >Preconditions: GetProblem().GetOperator() != 0 (return -1) MatrixShapeOk(GetProblem().GetOperator()) == true (return -6) <br >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_Umfpack.h
• Amesos_Umfpack.cpp

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