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

Class AbstractCosineDistanceFunction

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.AbstractCosineDistanceFunction

All Implemented Interfaces:

DistanceFunction<NumberVector<?,?>,DoubleDistance>, PrimitiveDistanceFunction<NumberVector<?,?>,DoubleDistance>, PrimitiveDoubleDistanceFunction<NumberVector<?,?>>, InspectionUtilFrequentlyScanned, Parameterizable

Direct Known Subclasses:

ArcCosineDistanceFunction, CosineDistanceFunction

public abstract class AbstractCosineDistanceFunction
extends AbstractVectorDoubleDistanceFunction

Abstract base class for Cosine and ArcCosine distances.

Constructor Summary

Constructors

Constructor and Description
AbstractCosineDistanceFunction() Constructor.

Method Summary

Methods

Modifier and Type	Method and Description
protected double	angle(NumberVector<?,?> v1, NumberVector<?,?> v2) Compute the angle between two vectors.
protected double	angleSparse(SparseNumberVector<?,?> v1, SparseNumberVector<?,?> v2) Compute the angle for sparse vectors.
<T extends NumberVector<?,?>> PrimitiveDistanceQuery<T,DoubleDistance>	instantiate(Relation<T> relation) Instantiate with a database to get the actual distance query.

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

distance, getDistanceFactory, getInputTypeRestriction

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

isMetric, isSymmetric

Methods inherited from class java.lang.Object

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

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

doubleDistance

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

isMetric, isSymmetric

Constructor Detail

AbstractCosineDistanceFunction

public AbstractCosineDistanceFunction()

Constructor.

Method Detail

angle

protected double angle(NumberVector<?,?> v1,
           NumberVector<?,?> v2)

Compute the angle between two vectors.

Parameters:

v1 - first vector

v2 - second vector

Returns:

Angle

angleSparse

protected double angleSparse(SparseNumberVector<?,?> v1,
                 SparseNumberVector<?,?> v2)

Compute the angle for sparse vectors.

Parameters:

v1 - First vector

v2 - Second vector

Returns:

angle

instantiate

public <T extends NumberVector<?,?>> PrimitiveDistanceQuery<T,DoubleDistance> instantiate(Relation<T> relation)

Description copied from class: AbstractPrimitiveDistanceFunction

Instantiate with a database to get the actual distance query.

Specified by:

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

Overrides:

instantiate in class AbstractPrimitiveDistanceFunction<NumberVector<?,?>,DoubleDistance>

Parameters:

relation - Representation

Returns:

Actual distance query.