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>, InspectionUtilFrequentlyScanned, Parameterizable

Direct Known Subclasses:

SimilarityAdapterArccos, SimilarityAdapterLinear, SimilarityAdapterLn

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

static class	AbstractSimilarityAdapter.Instance<O> Inner proxy class for SNN distance function.
static class	AbstractSimilarityAdapter.Parameterizer<O> Parameterization class.

Field Summary

static OptionID	SIMILARITY_FUNCTION_ID Parameter to specify the similarity function to derive the distance between database objects from.
protected NormalizedSimilarityFunction<? super O,? extends NumberDistance<?,?>>	similarityFunction Holds the similarity function.

Constructor Summary

AbstractSimilarityAdapter(NormalizedSimilarityFunction<? super O,? extends NumberDistance<?,?>> similarityFunction)
Constructor.

Method Summary

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,? extends NumberDistance<?,?>> similarityFunction

Holds the similarity function.

Constructor Detail

AbstractSimilarityAdapter

public AbstractSimilarityAdapter(NormalizedSimilarityFunction<? super O,? extends NumberDistance<?,?>> 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