de.lmu.ifi.dbs.elki.distance.distancefunction
Class ArcCosineDistanceFunction<V extends NumberVector<V,?>>

java.lang.Object
  de.lmu.ifi.dbs.elki.logging.AbstractLoggable
      de.lmu.ifi.dbs.elki.distance.AbstractMeasurementFunction<O,D>
          de.lmu.ifi.dbs.elki.distance.distancefunction.AbstractDistanceFunction<V,DoubleDistance>
              de.lmu.ifi.dbs.elki.distance.distancefunction.ArcCosineDistanceFunction<V>

Type Parameters:

V - the type of FeatureVector to compute the distances in between

All Implemented Interfaces:

DistanceFunction<V,DoubleDistance>, MeasurementFunction<V,DoubleDistance>, Parameterizable

public class ArcCosineDistanceFunction<V extends NumberVector<V,?>>
extends AbstractDistanceFunction<V,DoubleDistance>

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

Author:

Arthur Zimek

Field Summary

Fields inherited from class de.lmu.ifi.dbs.elki.distance.AbstractMeasurementFunction

distanceFactory

Fields inherited from class de.lmu.ifi.dbs.elki.logging.AbstractLoggable

debug, logger

Constructor Summary

ArcCosineDistanceFunction()
Provides a CosineDistanceFunction.

Method Summary

DoubleDistance

distance(V v1, V v2) Computes the cosine distance for two given feature vectors.

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

distance, distance

Methods inherited from class de.lmu.ifi.dbs.elki.distance.AbstractMeasurementFunction

getDatabase, getDistanceFactory, infiniteDistance, nullDistance, setDatabase, undefinedDistance, valueOf

Methods inherited from class de.lmu.ifi.dbs.elki.logging.AbstractLoggable

debugFine, debugFiner, debugFinest, exception, progress, verbose, warning

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.MeasurementFunction

getDistanceFactory, infiniteDistance, nullDistance, setDatabase, undefinedDistance, valueOf

Constructor Detail

ArcCosineDistanceFunction

public ArcCosineDistanceFunction()

Provides a CosineDistanceFunction.

Method Detail

distance

public DoubleDistance distance(V v1,
                               V 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