de.lmu.ifi.dbs.elki.normalization
Interface Normalization<O extends DatabaseObject>

Type Parameters:

O - object type

All Superinterfaces:

Parameterizable

All Known Implementing Classes:

AbstractNormalization, AttributeWiseMinMaxNormalization, AttributeWiseVarianceNormalization, DummyNormalization, MultiRepresentedObjectNormalization

public interface Normalization<O extends DatabaseObject>
extends Parameterizable

Normalization performs a normalization on a set of feature vectors and is capable to transform a set of feature vectors to the original attribute ranges.

It can also transform a matrix describing an equation system of linear dependencies derived on the normalized space to describe linear dependencies quantitatively adapted to the original space.

Author:

Arthur Zimek

Method Summary

List<O>	normalize(List<O> featureVectors) Performs a normalization on a set of feature vectors.
List<Pair<O,Associations>>	normalizeObjects(List<Pair<O,Associations>> objectAndAssociationsList) Performs a normalization on a list of database objects and their associations.
List<O>	restore(List<O> featureVectors) Transforms a set of feature vectores to the original attribute ranges.
O	restore(O featureVector) Transforms a feature vector to the original attribute ranges.
String	toString(String pre) Returns a string representation of this normalization.
LinearEquationSystem	transform(LinearEquationSystem linearEquationSystem) Transforms a linear equation system describing linear dependencies derived on the normalized space into a linear equation system describing linear dependencies quantitatively adapted to the original space.

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

checkGlobalParameterConstraints, collectOptions, getParameters, setParameters, shortDescription

Method Detail

normalizeObjects

List<Pair<O,Associations>> normalizeObjects(List<Pair<O,Associations>> objectAndAssociationsList)
                                                                   throws NonNumericFeaturesException

Performs a normalization on a list of database objects and their associations.

Parameters:

objectAndAssociationsList - the list of database objects and their associations

Returns:

a list of normalized database objects and their associations corresponding to the given list

Throws:

NonNumericFeaturesException - if feature vectors differ in length or values are not suitable to normalization

normalize

List<O> normalize(List<O> featureVectors)
                                         throws NonNumericFeaturesException

Performs a normalization on a set of feature vectors.

Parameters:

featureVectors - a set of feature vectors to be normalized

Returns:

a set of normalized feature vectors corresponding to the given feature vectors but being different objects

Throws:

NonNumericFeaturesException - if feature vectors differ in length or values are not suitable to normalization

restore

List<O> restore(List<O> featureVectors)
                                       throws NonNumericFeaturesException

Transforms a set of feature vectores to the original attribute ranges.

Parameters:

featureVectors - a set of feature vectors to be transformed into original space

Returns:

a set of feature vectors transformed into original space corresponding to the given feature vectors

Throws:

NonNumericFeaturesException - if feature vectors differ in length or are not compatible with values initialized during normalization

restore

O restore(O featureVector)
                                 throws NonNumericFeaturesException

Transforms a feature vector to the original attribute ranges.

Parameters:

featureVector - a feature vector to be transformed into original space

Returns:

a feature vector transformed into original space corresponding to the given feature vector

Throws:

NonNumericFeaturesException - feature vector is not compatible with values initialized during normalization

transform

LinearEquationSystem transform(LinearEquationSystem linearEquationSystem)
                               throws NonNumericFeaturesException

Transforms a linear equation system describing linear dependencies derived on the normalized space into a linear equation system describing linear dependencies quantitatively adapted to the original space.

Parameters:

linearEquationSystem - the linear equation system to be transformed

Returns:

a linear equation system describing linear dependencies derived on the normalized space transformed into a linear equation system describing linear dependencies quantitatively adapted to the original space

Throws:

NonNumericFeaturesException - if specified linear equation system is not compatible with values initialized during normalization

toString

String toString(String pre)

Returns a string representation of this normalization. The specified prefix pre will be the prefix of each new line. This method is used to write the parameters of a normalization to a result of an algorithm using this normalization.

Parameters:

pre - the prefix of each new line

Returns:

a string representation of this normalization