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

AbstractCosineDistanceFunction()
Constructor.

Method Summary

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.