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

Class ArcCosineDistanceFunction

java.lang.Object

de.lmu.ifi.dbs.elki.distance.distancefunction.AbstractPrimitiveDistanceFunction<NumberVector<?>,DoubleDistance>

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

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

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

All Implemented Interfaces:

DistanceFunction<NumberVector<?>,DoubleDistance>, NumberVectorDistanceFunction<DoubleDistance>, PrimitiveDistanceFunction<NumberVector<?>,DoubleDistance>, PrimitiveDoubleDistanceFunction<NumberVector<?>>, SpatialPrimitiveDistanceFunction<NumberVector<?>,DoubleDistance>, SpatialPrimitiveDoubleDistanceFunction<NumberVector<?>>, Parameterizable

@Alias(value="arccos")
public class ArcCosineDistanceFunction
extends AbstractSpatialDoubleDistanceFunction

Cosine distance function for feature vectors. The cosine distance is computed as the arcus from the cosine similarity value, i.e., arccos(<v1,v2>).

Nested Class Summary

Nested Classes

Modifier and Type	Class and Description
static class	ArcCosineDistanceFunction.Parameterizer Parameterization class.

Field Summary

Fields

Modifier and Type	Field and Description
static ArcCosineDistanceFunction	STATIC Static instance

Constructor Summary

Constructors

Constructor and Description
ArcCosineDistanceFunction() Deprecated. Use static instance!

Method Summary

Methods

Modifier and Type	Method and Description
double	doubleDistance(NumberVector<?> v1, NumberVector<?> v2) Computes the cosine distance for two given feature vectors.
double	doubleMinDist(SpatialComparable mbr1, SpatialComparable mbr2) Computes the distance between the two given MBRs according to this distance function.
boolean	equals(Object obj)
SimpleTypeInformation<? super NumberVector<?>>	getInputTypeRestriction() Get the input data type of the function.
String	toString()

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

instantiate, minDist

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

dimensionality, dimensionality, dimensionality, dimensionality, distance, getDistanceFactory

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

isMetric, isSymmetric

Methods inherited from class java.lang.Object

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

Methods inherited from interface de.lmu.ifi.dbs.elki.distance.distancefunction.PrimitiveDistanceFunction

distance

Methods inherited from interface de.lmu.ifi.dbs.elki.distance.distancefunction.DistanceFunction

getDistanceFactory, isMetric, isSymmetric

Field Detail

STATIC

public static final ArcCosineDistanceFunction STATIC

Static instance

Constructor Detail

ArcCosineDistanceFunction

@Deprecated
public ArcCosineDistanceFunction()

Deprecated. Use static instance!

Provides a CosineDistanceFunction.

Method Detail

doubleDistance

public double doubleDistance(NumberVector<?> v1,
                    NumberVector<?> v2)

Computes the cosine distance for two given feature vectors. The cosine distance is computed as the arcus from the cosine similarity value, i.e., arccos(<v1,v2>).

Parameters:

v1 - first feature vector

v2 - second feature vector

Returns:

the cosine distance for two given feature vectors v1 and v2

doubleMinDist

public double doubleMinDist(SpatialComparable mbr1,
                   SpatialComparable mbr2)

Description copied from interface: SpatialPrimitiveDoubleDistanceFunction

Computes the distance between the two given MBRs according to this distance function.

Parameters:

mbr1 - the first MBR object

mbr2 - the second MBR object

Returns:

the distance between the two given MBRs according to this distance function

toString

public String toString()

Overrides:

toString in class Object

equals

public boolean equals(Object obj)

Overrides:

equals in class Object

getInputTypeRestriction

public SimpleTypeInformation<? super NumberVector<?>> getInputTypeRestriction()

Description copied from interface: DistanceFunction

Get the input data type of the function.

Specified by:

getInputTypeRestriction in interface DistanceFunction<NumberVector<?>,DoubleDistance>

Specified by:

getInputTypeRestriction in interface PrimitiveDistanceFunction<NumberVector<?>,DoubleDistance>

Overrides:

getInputTypeRestriction in class AbstractVectorDoubleDistanceFunction

Returns:

Type restriction