org.ejml.alg.dense.decomposition.lu

Class LUDecompositionBase_D64

java.lang.Object

org.ejml.alg.dense.decomposition.lu.LUDecompositionBase_D64

All Implemented Interfaces:

DecompositionInterface<DenseMatrix64F>, LUDecomposition<DenseMatrix64F>

Direct Known Subclasses:

LUDecompositionAlt_D64, LUDecompositionNR_D64

public abstract class LUDecompositionBase_D64
extends java.lang.Object
implements LUDecomposition<DenseMatrix64F>

Contains common data structures and operations for LU decomposition algorithms.

Constructor Summary

Constructors

Constructor and Description
LUDecompositionBase_D64()

Method Summary

Modifier and Type	Method and Description
double[]	_getVV()
void	_solveVectorInternal(double[] vv) a specialized version of solve that avoid additional checks that are not needed.
Complex64F	computeDeterminant() Computes the determinant from the LU decomposition.
int[]	getIndx()
DenseMatrix64F	getLower(DenseMatrix64F lower) Writes the lower triangular matrix into the specified matrix.
DenseMatrix64F	getLU()
int[]	getPivot()
DenseMatrix64F	getPivot(DenseMatrix64F pivot) For numerical stability there are often row interchanges.
DenseMatrix64F	getUpper(DenseMatrix64F upper) Writes the upper triangular matrix into the specified matrix.
boolean	inputModified() Is the input matrix to DecompositionInterface.decompose(org.ejml.data.Matrix) is modified during the decomposition process.
boolean	isSingular() Determines if the decomposed matrix is singular.
double	quality()
void	setExpectedMaxSize(int numRows, int numCols)

Methods inherited from class java.lang.Object

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

Methods inherited from interface org.ejml.interfaces.decomposition.DecompositionInterface

decompose

Constructor Detail

LUDecompositionBase_D64

public LUDecompositionBase_D64()

Method Detail

setExpectedMaxSize

public void setExpectedMaxSize(int numRows,
                               int numCols)

getLU

public DenseMatrix64F getLU()

getIndx

public int[] getIndx()

getPivot

public int[] getPivot()

inputModified

public boolean inputModified()

Description copied from interface: DecompositionInterface

Is the input matrix to DecompositionInterface.decompose(org.ejml.data.Matrix) is modified during the decomposition process.

Specified by:

inputModified in interface DecompositionInterface<DenseMatrix64F>

Returns:

true if the input matrix to decompose() is modified.

getLower

public DenseMatrix64F getLower(DenseMatrix64F lower)

Writes the lower triangular matrix into the specified matrix.

Specified by:

getLower in interface LUDecomposition<DenseMatrix64F>

Parameters:

lower - Where the lower triangular matrix is writen to.

Returns:

The L matrix.

getUpper

public DenseMatrix64F getUpper(DenseMatrix64F upper)

Writes the upper triangular matrix into the specified matrix.

Specified by:

getUpper in interface LUDecomposition<DenseMatrix64F>

Parameters:

upper - Where the upper triangular matrix is writen to.

Returns:

The U matrix.

getPivot

public DenseMatrix64F getPivot(DenseMatrix64F pivot)

Description copied from interface: LUDecomposition

For numerical stability there are often row interchanges. This computes a pivot matrix that will undo those changes.

Specified by:

getPivot in interface LUDecomposition<DenseMatrix64F>

Parameters:

pivot - Storage for the pivot matrix. If null then a new matrix is returned. Modified.

Returns:

The pivot matrix.

isSingular

public boolean isSingular()

Determines if the decomposed matrix is singular. This function can return false and the matrix be almost singular, which is still bad.

Specified by:

isSingular in interface LUDecomposition<DenseMatrix64F>

Returns:

true if singular false otherwise.

computeDeterminant

public Complex64F computeDeterminant()

Computes the determinant from the LU decomposition.

Specified by:

computeDeterminant in interface LUDecomposition<DenseMatrix64F>

Returns:

The matrix's determinant.

quality

public double quality()

_solveVectorInternal

public void _solveVectorInternal(double[] vv)

a specialized version of solve that avoid additional checks that are not needed.

_getVV

public double[] _getVV()