de.lmu.ifi.dbs.elki.math.linearalgebra.pca.filter

Interface EigenPairFilter

All Known Implementing Classes:

DropEigenPairFilter, FirstNEigenPairFilter, LimitEigenPairFilter, PercentageEigenPairFilter, ProgressiveEigenPairFilter, RelativeEigenPairFilter, SignificantEigenPairFilter, WeakEigenPairFilter

public interface EigenPairFilter

The eigenpair filter is used to filter eigenpairs (i.e. eigenvectors and their corresponding eigenvalues) which are a result of a Variance Analysis Algorithm, e.g. Principal Component Analysis. The eigenpairs are filtered into two types: strong and weak eigenpairs, where strong eigenpairs having high variances and weak eigenpairs having small variances.

Since:

0.1

Author:

Elke Achtert

Field Summary

Fields

Modifier and Type	Field and Description
static OptionID	PCA_EIGENPAIR_FILTER Parameter to specify the filter for determination of the strong and weak eigenvectors, must be a subclass of EigenPairFilter.

Method Summary

Modifier and Type	Method and Description
int	filter(double[] eigenValues) Filters the specified eigenvalues into strong and weak eigenvalues, where strong eigenvalues have high variance and weak eigenvalues have small variance.

Field Detail

PCA_EIGENPAIR_FILTER

static final OptionID PCA_EIGENPAIR_FILTER

Parameter to specify the filter for determination of the strong and weak eigenvectors, must be a subclass of EigenPairFilter.

Method Detail

filter

int filter(double[] eigenValues)

Filters the specified eigenvalues into strong and weak eigenvalues, where strong eigenvalues have high variance and weak eigenvalues have small variance.

Parameters:

eigenValues - the array of eigenvalues, must be sorted descending

Returns:

the number of eigenvectors to keep