de.lmu.ifi.dbs.elki.math.linearalgebra.pca
Class FirstNEigenPairFilter

java.lang.Object
  de.lmu.ifi.dbs.elki.logging.AbstractLoggable
      de.lmu.ifi.dbs.elki.utilities.optionhandling.AbstractParameterizable
          de.lmu.ifi.dbs.elki.math.linearalgebra.pca.FirstNEigenPairFilter

All Implemented Interfaces:

EigenPairFilter, Parameterizable

public class FirstNEigenPairFilter
extends AbstractParameterizable
implements EigenPairFilter

The FirstNEigenPairFilter marks the n highest eigenpairs as strong eigenpairs, where n is a user specified number.

Author:

Elke Achtert

Field Summary

static OptionID	EIGENPAIR_FILTER_N OptionID for N_PARAM
private double	n The threshold for strong eigenvectors: n eigenvectors with the n highest eigenvalues are marked as strong eigenvectors.
private IntParameter	N_PARAM Parameter n.

Fields inherited from class de.lmu.ifi.dbs.elki.utilities.optionhandling.AbstractParameterizable

optionHandler

Fields inherited from class de.lmu.ifi.dbs.elki.logging.AbstractLoggable

debug, logger

Constructor Summary

FirstNEigenPairFilter()
Provides a new EigenPairFilter that sorts the eigenpairs in descending order of their eigenvalues and marks the first n eigenpairs as strong eigenpairs.

Method Summary

FilteredEigenPairs	filter(SortedEigenPairs eigenPairs) Filters the specified eigenpairs into strong and weak eigenpairs, where strong eigenpairs having high variances and weak eigenpairs having small variances.
List<String>	setParameters(List<String> args) Calls the super method and sets additionally the value of the parameter N_PARAM.
String	shortDescription() Returns a short description of the class.

Methods inherited from class de.lmu.ifi.dbs.elki.utilities.optionhandling.AbstractParameterizable

addOption, addParameterizable, addParameterizable, checkGlobalParameterConstraints, collectOptions, getAttributeSettings, getParameters, rememberParametersExcept, removeOption, removeParameterizable

Methods inherited from class de.lmu.ifi.dbs.elki.logging.AbstractLoggable

debugFine, debugFiner, debugFinest, exception, progress, verbose, warning

Methods inherited from class java.lang.Object

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

Methods inherited from interface de.lmu.ifi.dbs.elki.utilities.optionhandling.Parameterizable

checkGlobalParameterConstraints, collectOptions, getParameters

Field Detail

EIGENPAIR_FILTER_N

public static final OptionID EIGENPAIR_FILTER_N

OptionID for N_PARAM

N_PARAM

private final IntParameter N_PARAM

Parameter n.

n

private double n

The threshold for strong eigenvectors: n eigenvectors with the n highest eigenvalues are marked as strong eigenvectors.

Constructor Detail

FirstNEigenPairFilter

public FirstNEigenPairFilter()

Provides a new EigenPairFilter that sorts the eigenpairs in descending order of their eigenvalues and marks the first n eigenpairs as strong eigenpairs.

Method Detail

filter

public FilteredEigenPairs filter(SortedEigenPairs eigenPairs)

Description copied from interface: EigenPairFilter

Filters the specified eigenpairs into strong and weak eigenpairs, where strong eigenpairs having high variances and weak eigenpairs having small variances.

Specified by:

filter in interface EigenPairFilter

Parameters:

eigenPairs - the eigenPairs (i.e. the eigenvectors and

Returns:

the filtered eigenpairs

shortDescription

public String shortDescription()

Description copied from class: AbstractParameterizable

Returns a short description of the class.

Specified by:

shortDescription in interface Parameterizable

Overrides:

shortDescription in class AbstractParameterizable

Returns:

Description of the class

setParameters

public List<String> setParameters(List<String> args)
                           throws ParameterException

Calls the super method and sets additionally the value of the parameter N_PARAM.

Specified by:

setParameters in interface Parameterizable

Overrides:

setParameters in class AbstractParameterizable

Parameters:

args - parameters to set the attributes accordingly to

Returns:

a list containing the unused parameters

Throws:

ParameterException - in case of wrong parameter-setting