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PrecRILU Class Reference

RILU(w) preconditioner for linear systems. More...

#include <PrecAlgebraic.h>

Inheritance diagram for PrecRILU::

List of all members.

Public Methods
	PrecRILU (const Precond_prm &p)
virtual	~PrecRILU ()
virtual void	init (PrecBasis &Apb)
virtual void	apply (const LinEqVector &c, LinEqVector &d, TransposeMode tpmode=NOT_TRANSPOSED)
virtual int	getWork (const PrecondWork work_tp=APPLY_PREC_WORK) const
virtual real	getStorage () const
virtual void	performance (PrecondStatistics &precStat)
virtual String	description () const

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Detailed Description

RILU(w) preconditioner for linear systems.

NAME: PrecRILU - RILU(w) preconditioner for linear systems.

DESCRIPTION:

This class computes and applies the RILU factorization based on a given coefficient matrix. For the relaxation parameter "omega" = 0 this is equivalent to ILU, while "omega" = 1 leads to the unperturbed MILU preconditioner. Note that the factorization is restricted to fill-in level 0, i.e., no fill-in is allowed.

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Constructor & Destructor Documentation

PrecRILU::PrecRILU ( const Precond_prm & p )

The only constructor accepts a "Precond_prm" object.

PrecRILU::~PrecRILU ( ) [inline, virtual]

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Member Function Documentation

void PrecRILU::apply ( const LinEqVector & c, LinEqVector & d, TransposeMode tpmode = NOT_TRANSPOSED ) [virtual]

computes the result of applying the current preconditoner to a "LinEqVector" object "c". The result is returned in "d". Depending on the "TransposeMode" parameter, the preconditoner can be used as is (default) or as transposed/conjugate transposed operator. Reimplemented from PrecAlgebraic.

String PrecRILU::description ( ) const [virtual]

Reimplemented from Precond.

real PrecRILU::getStorage ( ) const [virtual]

returns the amount of storage needed for the current preconditioner. Reimplemented from PrecAlgebraic.

int PrecRILU::getWork ( const PrecondWork work_tp = APPLY_PREC_WORK ) const [virtual]

returns the work estimate for the last performed preconditioning operation. Reimplemented from Precond.

void PrecRILU::init ( PrecBasis & Apb ) [virtual]

initializes the preconditioner, e.g. by computing an incomplete factorization. The function "init" should perform internal redimensioning if necessary. For algebraic preconditioners where C is based directly on A with the same sparsity pattern, C should be redimensioned by a "C.redim(A)" statement like we have for "LinEqVector" objects. The "Matrix"-heriarchy must then have a virtual makeItSimilar function (see "Vector"). Reimplemented from PrecAlgebraic.

void PrecRILU::performance ( PrecondStatistics & precStat ) [virtual]

records preconditioning statistics in the supplied "PrecondStatistics" object. This object is usually a part of a "LinEqStatBlk" object which is used to collect and performance statistics. Reimplemented from Precond.

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

• PrecAlgebraic.h

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