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

Class ClarkDistanceFunction

java.lang.Object

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

All Implemented Interfaces:

DistanceFunction<NumberVector>, NumberVectorDistanceFunction<NumberVector>, PrimitiveDistanceFunction<NumberVector>, SpatialPrimitiveDistanceFunction<NumberVector>

@Priority(value=200)
 @Reference(authors="M.-M. Deza, E. Deza",
           title="Dictionary of distances",
           booktitle="Dictionary of distances",
           url="https://doi.org/10.1007/978-3-642-00234-2",
           bibkey="doi:10.1007/978-3-642-00234-2")
public class ClarkDistanceFunction
extends java.lang.Object
implements SpatialPrimitiveDistanceFunction<NumberVector>, NumberVectorDistanceFunction<NumberVector>

Clark distance function for vector spaces.

Clark distance is defined as: \[ \text{Clark}(\vec{x},\vec{y}) := \sqrt{\tfrac{1}{d}\sum\nolimits_i \left(\tfrac{|x_i-y_i|}{|x_i|+|y_i|}\right)^2} \]

Reference:

M.-M. Deza, E. Deza
Dictionary of distances

Since:

0.6.0

Author:

Erich Schubert

Nested Class Summary

Nested Classes

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

Field Summary

Fields

Modifier and Type	Field and Description
static ClarkDistanceFunction	STATIC Static instance.

Constructor Summary

Constructors

Constructor and Description
ClarkDistanceFunction() Deprecated. Use STATIC instance instead.

Method Summary

Modifier and Type	Method and Description
double	distance(NumberVector v1, NumberVector v2) Computes the distance between two given DatabaseObjects according to this distance function.
boolean	equals(java.lang.Object obj)
SimpleTypeInformation<? super NumberVector>	getInputTypeRestriction() Get the input data type of the function.
int	hashCode()
double	minDist(SpatialComparable mbr1, SpatialComparable mbr2) Computes the distance between the two given MBRs according to this distance function.

Methods inherited from class java.lang.Object

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

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

instantiate

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

isMetric, isSquared, isSymmetric

Field Detail

STATIC

public static final ClarkDistanceFunction STATIC

Static instance.

Constructor Detail

ClarkDistanceFunction

@Deprecated
public ClarkDistanceFunction()

Deprecated. Use STATIC instance instead.

Constructor.

Method Detail

distance

public double distance(NumberVector v1,
                       NumberVector v2)

Description copied from interface: PrimitiveDistanceFunction

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

Specified by:

distance in interface NumberVectorDistanceFunction<NumberVector>

Specified by:

distance in interface PrimitiveDistanceFunction<NumberVector>

Parameters:

v1 - first DatabaseObject

v2 - second DatabaseObject

Returns:

the distance between two given DatabaseObjects according to this distance function

minDist

public double minDist(SpatialComparable mbr1,
                      SpatialComparable mbr2)

Description copied from interface: SpatialPrimitiveDistanceFunction

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

Specified by:

minDist in interface SpatialPrimitiveDistanceFunction<NumberVector>

Parameters:

mbr1 - the first MBR object

mbr2 - the second MBR object

Returns:

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

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>

Specified by:

getInputTypeRestriction in interface PrimitiveDistanceFunction<NumberVector>

Returns:

Type restriction

equals

public boolean equals(java.lang.Object obj)

Overrides:

equals in class java.lang.Object

hashCode

public int hashCode()

Overrides:

hashCode in class java.lang.Object