jvx.numeric

Class PnJacobi

java.lang.Object

jv.object.PsObject

jvx.numeric.PnJacobi

All Implemented Interfaces:

java.io.Serializable, java.lang.Cloneable, PsUpdateIf

public class PnJacobi
extends PsObject

Compute eigenvectors and eigenvalues of a given symmetric matrix and store in result vectors.

See Also:

Serialized Form

Author:

Konrad Polthier

Version:

04.02.15, 2.31 revised (kp) Doc improved, mention requirement of symmetric matrices.
20.12.01, 2.30 revised (ep) Internationalization.
08.11.00, 2.20 revised (kp) Replace formatting with PuString rather than Fmt.
08.09.99, 2.10 revised (kp) Moved to project jv.numeric from jv.geom.
07.09.99, 2.00 revised (kp) ComputeEigenvectors() converted to static method.
00.00.98, 1.00 created (kp)

Field Summary

Fields

Modifier and Type	Field and Description
static int	FAILURE Return value of computation method if failure.
static int	INTERRUPTED Return value of computation method if interrupted from outside.

Fields inherited from class jv.object.PsObject

HAS_BOUNDARY_PANEL, HAS_CONFIG_PANEL, HAS_INFO_PANEL, HAS_LABEL_PANEL, HAS_MATERIAL_PANEL, HAS_TEXTURE_PANEL, HAS_VECTOR_PANEL, INSPECTOR_INFO, INSPECTOR_INFO_EXT, IS_DELETED, IS_FIXED, IS_FOCUSSED, IS_PICKED, IS_SELECTED, IS_USED, NUM_TAGS

Constructor Summary

Constructors

Constructor and Description
PnJacobi()

Method Summary

Modifier and Type	Method and Description
static int	computeEigenvectors(PdMatrix mat, int dim, PdVector eValue, PdVector[] eVector) Compute eigenvectors and eigenvalues of a given symmetric matrix and store in result vectors.
static int	fcomputeEigenvectors(PdMatrix mat, int dim, PdVector eValue, PdVector[] eVector) Compute eigenvectors and eigenvalues of a given symmetric matrix and store in result vectors.
boolean	isDoublePrecision()
static boolean	isInterrupted() Get flag if the previous computation was interrupted from outside.
static void	printEigenvalues(int dim, PdVector eValue) Sort eigenvalues by increasing eigenvalue and print to JavaView console.
static void	printEigenvectors(int dim, PdVector eValue, PdVector[] eVector) Sort eigenvalues and eigenvectors by increasing eigenvalue and print to JavaView console.
void	setDoublePrecision(boolean flag) Set flag weather computations are done in double or single precision.
static void	setInterrupted(boolean flag) Flag set from outside to interrupt the current computation.
static boolean	test(PdMatrix mat, int dim, PdVector eValue, PdVector[] eVector) Test method validates if given eigenvectors are indeed eigenvectors of given matrix.

Methods inherited from class jv.object.PsObject

addInspector, addUpdateListener, assureInspector, clearTag, clone, clone, clone, copy, getFather, getInfoPanel, getInspector, getName, getNumObjects, getSymbol, hasInspector, hasTag, hasUpdateListener, init, instanceOf, instanceOf, newInspector, newInspector, removeInspector, removeInspector, removeUpdateListener, setName, setParent, setSymbol, setTag, toString, update, updatePanels

Methods inherited from class java.lang.Object

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

Field Detail

FAILURE

public static final int FAILURE

Return value of computation method if failure.

See Also:

Constant Field Values

INTERRUPTED

public static final int INTERRUPTED

Return value of computation method if interrupted from outside.

See Also:

Constant Field Values

Constructor Detail

PnJacobi

public PnJacobi()

Method Detail

setInterrupted

public static void setInterrupted(boolean flag)

Flag set from outside to interrupt the current computation. When a computation method is called then this flag is reset.

isInterrupted

public static boolean isInterrupted()

Get flag if the previous computation was interrupted from outside. Call this method after computeEigenvectors.

setDoublePrecision

public void setDoublePrecision(boolean flag)

Set flag weather computations are done in double or single precision.

isDoublePrecision

public boolean isDoublePrecision()

computeEigenvectors

public static int computeEigenvectors(PdMatrix mat,
                                      int dim,
                                      PdVector eValue,
                                      PdVector[] eVector)

Compute eigenvectors and eigenvalues of a given symmetric matrix and store in result vectors. Method modifies the original matrix for internal use.

This method uses double-precision. See fcomputeEigenvectors which uses float-precision.

Parameters:

mat - Matrix whose eigenvalues and -vectors should be computed.

dim - Size of square matrix, length of vectors

eValue - Vector to store the computed eigenvalues

eVector - Array of vectors to store the computed eigenvectors

Returns:

Number of used iterations, or -1 if failure or -2 if interrupted.

Author:

Numerical Recipes, changed to Java and adapted by Konrad Polthier

Version:

21.07.02, 2.20 revised (kp) Allow interruption of computation.
08.09.99, 2.10 revised (kp) Keep input matrix untouched.
07.09.99, 2.00 revised (kp) Converted to static method.
24.04.99, 1.10 revised (kp) eVectors were transposed, corrected.
00.00.98, 1.00 created (kp)

fcomputeEigenvectors

public static int fcomputeEigenvectors(PdMatrix mat,
                                       int dim,
                                       PdVector eValue,
                                       PdVector[] eVector)

Compute eigenvectors and eigenvalues of a given symmetric matrix and store in result vectors. Method modifies the original matrix for internal use.

This method uses float-precision. See computeEigenvectors which uses double-precision.

Parameters:

mat - Matrix whose eigenvalues and -vectors should be computed.

dim - Size of square matrix, length of vectors

eValue - Vector to store the computed eigenvalues

eVector - Array of vectors to store the computed eigenvectors

Returns:

Number of used iterations, or -1 if failure or -2 if interrupted.

Author:

Numerical Recipes, changed to Java and adapted by Konrad Polthier

Version:

26.10.02, 1.00 created (kp) From same double-precision version.

printEigenvectors

public static void printEigenvectors(int dim,
                                     PdVector eValue,
                                     PdVector[] eVector)

Sort eigenvalues and eigenvectors by increasing eigenvalue and print to JavaView console.

Parameters:

dim - number of eigenvectors

eValue - array of eigenvalues

eVector - array of eigenvectors

Author:

Konrad Polthier

printEigenvalues

public static void printEigenvalues(int dim,
                                    PdVector eValue)

Sort eigenvalues by increasing eigenvalue and print to JavaView console.

Parameters:

dim - number of eigenvectors

eValue - array of eigenvalues

Author:

Konrad Polthier

test

public static boolean test(PdMatrix mat,
                           int dim,
                           PdVector eValue,
                           PdVector[] eVector)

Test method validates if given eigenvectors are indeed eigenvectors of given matrix. Difference between given and evaluated eigenvalue is printed to JavaView console.

Parameters:

dim - number of eigenvectors

eValue - array of eigenvalues

Author:

Konrad Polthier