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

All Methods
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