IdentityPreconditioner

java.lang.Object

org.ojalgo.matrix.task.iterative.IdentityPreconditioner

All Implemented Interfaces:: Preconditioner

final class IdentityPreconditioner extends Object implements Preconditioner

Identity (no-op) preconditioner.

Characteristics and usage

Works with any iterative method and serves as a baseline when no preconditioning is desired.
Safe choice for methods that require symmetry/positive-definiteness of the preconditioner.
Often used to measure the effect of adding a non-trivial preconditioner.

Field Summary

Fields inherited from interface Preconditioner
IDENTITY
Constructor Summary

Constructors

Constructor

Description

IdentityPreconditioner()
Method Summary

Modifier and Type

Method

Description

void

apply(Access1D<Double> src, PhysicalStore<Double> dst)

Apply M^{-1} to a vector.

void

prepare(List<Equation> equations, int dimension)

Prepare internal structures for a specific system.

Methods inherited from class Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Methods inherited from interface Preconditioner
applyTranspose

Constructor Details
- IdentityPreconditioner
  
  IdentityPreconditioner()
Method Details
- apply
  
  public void apply(Access1D<Double> src, PhysicalStore<Double> dst)
  
  Description copied from interface: Preconditioner
  
  Apply M^{-1} to a vector. src and dst may alias.
  
  Specified by:
  
  apply in interface Preconditioner
- prepare
  
  public void prepare(List<Equation> equations, int dimension)
  
  Description copied from interface: Preconditioner
  
  Prepare internal structures for a specific system. Implementations may analyse sparsity or extract diagonals/factors here.
  
  Specified by:
  
  prepare in interface Preconditioner
  
  Parameters:
  
  equations - The active set of rows constituting the system body.
  
  dimension - The vector dimension (number of variables / size of solution vector).