no.uib.cipr.matrix.sparse

Class ILU

java.lang.Object

no.uib.cipr.matrix.sparse.ILU

All Implemented Interfaces:

Preconditioner

public class ILU
extends Object
implements Preconditioner

ILU(0) preconditioner using a compressed row matrix as internal storage

Constructor Summary

Constructors

Constructor and Description
ILU(CompRowMatrix LU) Sets up the ILU preconditioner

Method Summary

Methods

Modifier and Type	Method and Description
Vector	apply(Vector b, Vector x) Solves the approximate problem with the given right hand side.
void	setMatrix(Matrix A) Sets the operator matrix for the preconditioner.
Vector	transApply(Vector b, Vector x) Solves the approximate transpose problem with the given right hand side.

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Detail

ILU

public ILU(CompRowMatrix LU)

Sets up the ILU preconditioner

Parameters:

LU - Matrix to use internally. For best performance, its non-zero pattern must conform to that of the system matrix

Method Detail

apply

public Vector apply(Vector b,
           Vector x)

Description copied from interface: Preconditioner

Solves the approximate problem with the given right hand side. Result is stored in given solution vector

Specified by:

apply in interface Preconditioner

Parameters:

b - Right hand side of problem

x - Result is stored here

Returns:

x

transApply

public Vector transApply(Vector b,
                Vector x)

Description copied from interface: Preconditioner

Solves the approximate transpose problem with the given right hand side. Result is stored in given solution vector

Specified by:

transApply in interface Preconditioner

Parameters:

b - Right hand side of problem

x - Result is stored here

Returns:

x

setMatrix

public void setMatrix(Matrix A)

Description copied from interface: Preconditioner

Sets the operator matrix for the preconditioner. This method must be called before a preconditioner is used by an iterative solver

Specified by:

setMatrix in interface Preconditioner

Parameters:

A - Matrix to setup the preconditioner for. Not modified