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

Class LCSSDistanceFunction

java.lang.Object

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

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

All Implemented Interfaces:

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

@Title(value="Longest Common Subsequence distance function")
 @Reference(authors="M. Vlachos, M. Hadjieleftheriou, D. Gunopulos, E. Keogh",
           title="Indexing Multi-Dimensional Time-Series with Support for Multiple Distance Measures",
           booktitle="Proc. 9th ACM SIGKDD Int. Conf. on Knowledge Discovery and Data Mining",
           url="https://doi.org/10.1145/956750.956777",
           bibkey="DBLP:conf/kdd/VlachosHGK03")
public class LCSSDistanceFunction
extends AbstractNumberVectorDistanceFunction

Longest Common Subsequence distance for numerical vectors.

Originally this was based on the Matlab Code by Michalis Vlachos, but we have since switched to a version that uses less memory.

Reference:

M. Vlachos, M. Hadjieleftheriou, D. Gunopulos, E. Keogh
Indexing Multi-Dimensional Time-Series with Support for Multiple Distance Measures
Proc. 9th ACM SIGKDD Int. Conf. on Knowledge Discovery and Data Mining

Since:

0.2

Author:

Thomas Bernecker

Nested Class Summary

Nested Classes

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

Field Summary

Fields

Modifier and Type	Field and Description
private double	pDelta Keeps the currently set pDelta.
private double	pEpsilon Keeps the currently set pEpsilon.

Constructor Summary

Constructors

Constructor and Description
LCSSDistanceFunction(double pDelta, double pEpsilon) Constructor.

Method Summary

Modifier and Type	Method and Description
double	distance(NumberVector v1, NumberVector v2) Computes the distance between two given vectors according to this distance function.
boolean	equals(java.lang.Object obj)
VectorTypeInformation<? super NumberVector>	getInputTypeRestriction() Get the input data type of the function.
double	getRange(NumberVector v1, int dim1, NumberVector v2, int dim2)
int	hashCode()

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

dimensionality, dimensionality, dimensionality, dimensionality, dimensionality, dimensionality, dimensionality, dimensionality

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.PrimitiveDistanceFunction

instantiate

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

isMetric, isSquared, isSymmetric

Field Detail

pDelta

private double pDelta

Keeps the currently set pDelta.

pEpsilon

private double pEpsilon

Keeps the currently set pEpsilon.

Constructor Detail

LCSSDistanceFunction

public LCSSDistanceFunction(double pDelta,
                            double pEpsilon)

Constructor.

Parameters:

pDelta - pDelta

pEpsilon - pEpsilon

Method Detail

distance

public double distance(NumberVector v1,
                       NumberVector v2)

Description copied from interface: NumberVectorDistanceFunction

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

Parameters:

v1 - first vector

v2 - second vector

Returns:

the distance between two given vectors according to this distance function

getRange

public double getRange(NumberVector v1,
                       int dim1,
                       NumberVector v2,
                       int dim2)

getInputTypeRestriction

public VectorTypeInformation<? 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>

Overrides:

getInputTypeRestriction in class AbstractNumberVectorDistanceFunction

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