JacobiPreconditioner

java.lang.Object
- org.ojalgo.matrix.task.iterative.JacobiPreconditioner

All Implemented Interfaces:

Preconditioner
```
public final class JacobiPreconditioner
extends java.lang.Object
implements Preconditioner
```
Simple diagonal (Jacobi) preconditioner: M = diag(A), apply M^{-1} x = x ./ diag(A).
Compatibility
- Well-suited as a lightweight, symmetry-preserving choice for methods that benefit from SPD preconditioning when A has positive diagonal entries.
- Usable as a right-preconditioner in methods for general nonsymmetric systems where a transpose action equals the forward action.
- Ignored by stationary fixed-point methods that do not use preconditioners.

Field Summary

Fields
Modifier and Type Field Description

private R064Store myInvDiag
- Fields inherited from interface org.ojalgo.matrix.task.iterative.Preconditioner
  IDENTITY

Constructor Summary

Constructors
Constructor Description

JacobiPreconditioner()

Method Summary

All Methods Instance Methods Concrete Methods
Modifier and Type	Method	Description
`void`	`apply(Access1D<java.lang.Double> src, PhysicalStore<java.lang.Double> dst)`	Apply M^{-1} to a vector.
`void`	`prepare(java.util.List<Equation> equations, int dimension)`	Prepare internal structures for a specific system.

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

Methods inherited from interface org.ojalgo.matrix.task.iterative.Preconditioner
applyTranspose

- Field Detail
  - myInvDiag
```
private transient R064Store myInvDiag
```
- Constructor Detail
  - JacobiPreconditioner
```
public JacobiPreconditioner()
```
- Method Detail
  - apply
```
public void apply(Access1D<java.lang.Double> src,
                  PhysicalStore<java.lang.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(java.util.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).