org.ojalgo.matrix.jama
Class JamaEigenvalue

java.lang.Object
  org.ojalgo.matrix.jama.JamaEigenvalue

All Implemented Interfaces:

Eigenvalue<Double>, MatrixDecomposition<Double>

Direct Known Subclasses:

JamaEigenvalue.General, JamaEigenvalue.Nonsymmetric, JamaEigenvalue.Symmetric

public abstract class JamaEigenvalue
extends Object
implements Eigenvalue<Double>

This class adapts JAMA's EigenvalueDecomposition to ojAlgo's Eigenvalue interface.

Author:

apete

Nested Class Summary

static class	JamaEigenvalue.General
static class	JamaEigenvalue.Nonsymmetric
static class	JamaEigenvalue.Symmetric

Method Summary

boolean	compute(Access2D<?> aStore)
boolean	compute(Access2D<?> aMtrx, boolean eigenvaluesOnly)
boolean	equals(MatrixDecomposition<Double> aDecomp, NumberContext aCntxt)
boolean	equals(MatrixStore<Double> aStore, NumberContext aCntxt)
JamaMatrix	getD() The only requirements on [D] are that it should contain the eigenvalues and that [A][V] = [V][D].
ComplexNumber	getDeterminant() A matrix' determinant is the product of its eigenvalues.
Array1D<ComplexNumber>	getEigenvalues() Even for real matrices the eigenvalues are potentially complex numbers.
JamaMatrix	getInverse() The output must be a "right inverse" and a "generalised inverse".
MatrixStore<Double>	getInverse(DecompositionStore<Double> preallocated) Makes no use of preallocated at all.
ComplexNumber	getTrace() A matrix' trace is the sum of the diagonal elements.
JamaMatrix	getV() The columns of [V] represent the eigenvectors of [A] in the sense that [A][V] = [V][D].
JamaMatrix	invert(MatrixStore<Double> aStore)
boolean	isAspectRatioNormal()
boolean	isComputed()
boolean	isFullSize()
boolean	isOrdered()
boolean	isSolvable()
boolean	isSymmetric()
MatrixStore<Double>	reconstruct()
void	reset() Delete computed results, and resets attributes to default values
JamaMatrix	solve(MatrixStore<Double> aRHS) [A][X]=[B] or [this][return]=[aRHS]
JamaMatrix	solve(MatrixStore<Double> aRHS, DecompositionStore<Double> preallocated) Makes no use of preallocated at all.
String	toString()

Methods inherited from class java.lang.Object

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

Methods inherited from interface org.ojalgo.matrix.decomposition.MatrixDecomposition

compute, equals, getInverse, solve

Method Detail

compute

public boolean compute(Access2D<?> aMtrx,
                       boolean eigenvaluesOnly)

Specified by:

compute in interface Eigenvalue<Double>

Parameters:

aMtrx - A matrix to decompose

eigenvaluesOnly - No need to calculate eigenvectors

Returns:

true/false if the computation succeeded or not

equals

public boolean equals(MatrixStore<Double> aStore,
                      NumberContext aCntxt)

Specified by:

equals in interface MatrixDecomposition<Double>

getD

public JamaMatrix getD()

Description copied from interface: Eigenvalue

The only requirements on [D] are that it should contain the eigenvalues and that [A][V] = [V][D]. The ordering of the eigenvalues is not specified.

• If [A] is real and symmetric then [D] is (purely) diagonal with real eigenvalues.
• If [A] is real but not symmetric then [D] is block-diagonal with real eigenvalues in 1-by-1 blocks and complex eigenvalues in 2-by-2 blocks.
• If [A] is complex then [D] is (purely) diagonal with complex eigenvalues.

Specified by:

getD in interface Eigenvalue<Double>

Returns:

The (block) diagonal eigenvalue matrix.

getDeterminant

public ComplexNumber getDeterminant()

Description copied from interface: Eigenvalue

A matrix' determinant is the product of its eigenvalues.

Specified by:

getDeterminant in interface Eigenvalue<Double>

Returns:

The matrix' determinant

getEigenvalues

public Array1D<ComplexNumber> getEigenvalues()

Description copied from interface: Eigenvalue

Even for real matrices the eigenvalues are potentially complex numbers. Typically they need to be expressed as complex numbers when [A] is not symmetric.

The eigenvalues in this array should be ordered in descending order - largest (modulus) first.

Specified by:

getEigenvalues in interface Eigenvalue<Double>

Returns:

The eigenvalues in an ordered array.

getInverse

public JamaMatrix getInverse()

Description copied from interface: MatrixDecomposition

The output must be a "right inverse" and a "generalised inverse".

Specified by:

getInverse in interface MatrixDecomposition<Double>

See Also:

BasicMatrix.invert()

getTrace

public ComplexNumber getTrace()

Description copied from interface: Eigenvalue

A matrix' trace is the sum of the diagonal elements. It is also the sum of the eigenvalues. This method should return the sum of the eigenvalues.

Specified by:

getTrace in interface Eigenvalue<Double>

Returns:

The matrix' trace

getV

public JamaMatrix getV()

Description copied from interface: Eigenvalue

The columns of [V] represent the eigenvectors of [A] in the sense that [A][V] = [V][D].

Specified by:

getV in interface Eigenvalue<Double>

Returns:

The eigenvector matrix.

isAspectRatioNormal

public boolean isAspectRatioNormal()

isComputed

public boolean isComputed()

Specified by:

isComputed in interface MatrixDecomposition<Double>

Returns:

true if computation has been attemped; false if not.

See Also:

MatrixDecomposition.compute(Access2D), MatrixDecomposition.isSolvable()

isFullSize

public boolean isFullSize()

Specified by:

isFullSize in interface MatrixDecomposition<Double>

Returns:

True if the implementation generates a full sized decomposition.

isOrdered

public boolean isOrdered()

Specified by:

isOrdered in interface Eigenvalue<Double>

isSolvable

public boolean isSolvable()

Specified by:

isSolvable in interface MatrixDecomposition<Double>

Returns:

true if it is ok to call MatrixDecomposition.solve(MatrixStore) (computation was successful); false if not

See Also:

MatrixDecomposition.solve(MatrixStore), MatrixDecomposition.isComputed()

isSymmetric

public boolean isSymmetric()

Specified by:

isSymmetric in interface Eigenvalue<Double>

reconstruct

public MatrixStore<Double> reconstruct()

Specified by:

reconstruct in interface MatrixDecomposition<Double>

reset

public void reset()

Description copied from interface: MatrixDecomposition

Delete computed results, and resets attributes to default values

Specified by:

reset in interface MatrixDecomposition<Double>

solve

public JamaMatrix solve(MatrixStore<Double> aRHS)

Description copied from interface: MatrixDecomposition

[A][X]=[B] or [this][return]=[aRHS]

Specified by:

solve in interface MatrixDecomposition<Double>

toString

public String toString()

Overrides:

toString in class Object

compute

public final boolean compute(Access2D<?> aStore)

Specified by:

compute in interface MatrixDecomposition<Double>

Parameters:

aStore - A matrix to decompose

Returns:

true if the computation suceeded; false if not

equals

public final boolean equals(MatrixDecomposition<Double> aDecomp,
                            NumberContext aCntxt)

Specified by:

equals in interface MatrixDecomposition<Double>

getInverse

public final MatrixStore<Double> getInverse(DecompositionStore<Double> preallocated)

Makes no use of preallocated at all. Simply delegates to getInverse().

Specified by:

getInverse in interface MatrixDecomposition<Double>

Parameters:

preallocated - Preallocated memory for the results, possibly some intermediate results. You must assume this is modified, but you cannot assume it will contain the full/final/correct solution.

Returns:

The inverse

See Also:

MatrixDecomposition.getInverse(org.ojalgo.matrix.decomposition.DecompositionStore)

invert

public final JamaMatrix invert(MatrixStore<Double> aStore)

solve

public final JamaMatrix solve(MatrixStore<Double> aRHS,
                              DecompositionStore<Double> preallocated)

Makes no use of preallocated at all. Simply delegates to solve(MatrixStore).

Specified by:

solve in interface MatrixDecomposition<Double>

Parameters:

aRHS - The Right Hand Side, wont be modfied

preallocated - Preallocated memory for the results, possibly some intermediate results. You must assume this is modified, but you cannot assume it will contain the full/final/correct solution.

Returns:

The solution

See Also:

MatrixDecomposition.solve(org.ojalgo.matrix.store.MatrixStore, org.ojalgo.matrix.decomposition.DecompositionStore)