de.lmu.ifi.dbs.elki.distance.distancefunction.adapter

Class AbstractSimilarityAdapter<O>

java.lang.Object

de.lmu.ifi.dbs.elki.distance.distancefunction.AbstractDatabaseDistanceFunction<O,DoubleDistance>

de.lmu.ifi.dbs.elki.distance.distancefunction.adapter.AbstractSimilarityAdapter<O>

Type Parameters:

O - object class to process

All Implemented Interfaces:

DistanceFunction<O,DoubleDistance>, Parameterizable

Direct Known Subclasses:

ArccosSimilarityAdapter, LinearAdapterLinear, LnSimilarityAdapter

public abstract class AbstractSimilarityAdapter<O>
extends AbstractDatabaseDistanceFunction<O,DoubleDistance>

Adapter from a normalized similarity function to a distance function. Note: The derived distance function will usually not satisfy the triangle equation.

Nested Class Summary

Nested Classes

Modifier and Type	Class and Description
static class	AbstractSimilarityAdapter.Instance<O> Inner proxy class for SNN distance function.
static class	AbstractSimilarityAdapter.Parameterizer<O> Parameterization class.

Field Summary

Fields

Modifier and Type	Field and Description
static OptionID	SIMILARITY_FUNCTION_ID Parameter to specify the similarity function to derive the distance between database objects from.
protected NormalizedSimilarityFunction<? super O>	similarityFunction Holds the similarity function.

Constructor Summary

Constructors

Constructor and Description
AbstractSimilarityAdapter(NormalizedSimilarityFunction<? super O> similarityFunction) Constructor.

Method Summary

Methods

Modifier and Type	Method and Description
boolean	equals(Object obj)
DoubleDistance	getDistanceFactory() Method to get the distance functions factory.
TypeInformation	getInputTypeRestriction() Get the input data type of the function.
abstract <T extends O> DistanceQuery<T,DoubleDistance>	instantiate(Relation<T> database) Instantiate with a database to get the actual distance query.
boolean	isSymmetric() Is this function symmetric?

Methods inherited from class de.lmu.ifi.dbs.elki.distance.distancefunction.AbstractDatabaseDistanceFunction

isMetric

Methods inherited from class java.lang.Object

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

Field Detail

SIMILARITY_FUNCTION_ID

public static final OptionID SIMILARITY_FUNCTION_ID

Parameter to specify the similarity function to derive the distance between database objects from. Must extend NormalizedSimilarityFunction .

Key: -adapter.similarityfunction

Default value: FractionalSharedNearestNeighborSimilarityFunction

similarityFunction

protected NormalizedSimilarityFunction<? super O> similarityFunction

Holds the similarity function.

Constructor Detail

AbstractSimilarityAdapter

public AbstractSimilarityAdapter(NormalizedSimilarityFunction<? super O> similarityFunction)

Constructor.

Parameters:

similarityFunction - Similarity function to use.

Method Detail

getInputTypeRestriction

public TypeInformation getInputTypeRestriction()

Description copied from interface: DistanceFunction

Get the input data type of the function.

Returns:

Type restriction

isSymmetric

public boolean isSymmetric()

Description copied from interface: DistanceFunction

Is this function symmetric?

Specified by:

isSymmetric in interface DistanceFunction<O,DoubleDistance>

Overrides:

isSymmetric in class AbstractDatabaseDistanceFunction<O,DoubleDistance>

Returns:

true when symmetric

getDistanceFactory

public DoubleDistance getDistanceFactory()

Description copied from interface: DistanceFunction

Method to get the distance functions factory.

Specified by:

getDistanceFactory in interface DistanceFunction<O,DoubleDistance>

Specified by:

getDistanceFactory in class AbstractDatabaseDistanceFunction<O,DoubleDistance>

Returns:

Factory for distance objects

instantiate

public abstract <T extends O> DistanceQuery<T,DoubleDistance> instantiate(Relation<T> database)

Description copied from interface: DistanceFunction

Instantiate with a database to get the actual distance query.

Parameters:

database - The representation to use

Returns:

Actual distance query.

equals

public boolean equals(Object obj)

Overrides:

equals in class Object