Package elki.distance

Class ClarkDistance

java.lang.Object

elki.distance.ClarkDistance

All Implemented Interfaces:

Distance<NumberVector>, NumberVectorDistance<NumberVector>, PrimitiveDistance<NumberVector>, SpatialPrimitiveDistance<NumberVector>

@Priority(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 ClarkDistance
extends java.lang.Object
implements SpatialPrimitiveDistance<NumberVector>, NumberVectorDistance<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	Description
static class	ClarkDistance.Par	Parameterization class.

Field Summary

Fields

Modifier and Type	Field	Description
static ClarkDistance	STATIC	Static instance.

Constructor Summary

Constructors

Constructor	Description
ClarkDistance()	Deprecated. Use STATIC instance instead.

Method Summary

Modifier and Type	Method	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 elki.distance.Distance

isMetric, isSquared, isSymmetric

Methods inherited from interface elki.distance.SpatialPrimitiveDistance

instantiate

Field Detail

STATIC

public static final ClarkDistance STATIC

Static instance.

Constructor Detail

ClarkDistance

@Deprecated
public ClarkDistance()

Deprecated.

Use STATIC instance instead.

Constructor.

Method Detail

distance

public double distance(NumberVector v1,
                       NumberVector v2)

Description copied from interface: PrimitiveDistance

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

Specified by:

distance in interface NumberVectorDistance<NumberVector>

Specified by:

distance in interface PrimitiveDistance<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: SpatialPrimitiveDistance

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

Specified by:

minDist in interface SpatialPrimitiveDistance<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: Distance

Get the input data type of the function.

Specified by:

getInputTypeRestriction in interface Distance<NumberVector>

Specified by:

getInputTypeRestriction in interface PrimitiveDistance<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