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

Class NormalizedLevenshteinDistanceFunction

java.lang.Object

de.lmu.ifi.dbs.elki.distance.distancefunction.AbstractPrimitiveDistanceFunction<String,DoubleDistance>

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

All Implemented Interfaces:

DistanceFunction<String,DoubleDistance>, PrimitiveDistanceFunction<String,DoubleDistance>, Parameterizable

@Description(value="Levenshtein distance, normalized by average string length.")
@Reference(authors="V. I. Levenshtein",
           title="Binary codes capable of correcting deletions, insertions and reversals.",
           booktitle="Soviet physics doklady. Vol. 10. 1966.")
public class NormalizedLevenshteinDistanceFunction
extends AbstractPrimitiveDistanceFunction<String,DoubleDistance>

Levenshtein distance on strings, normalized by string length. Reference:

V. I. Levenshtein
Binary codes capable of correcting deletions, insertions and reversals.
Soviet physics doklady. Vol. 10. 1966.

TODO: add case insensitive flag.

Nested Class Summary

Nested Classes

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

Field Summary

Fields

Modifier and Type	Field and Description
static NormalizedLevenshteinDistanceFunction	STATIC_SENSITIVE Static instance, case sensitive.

Constructor Summary

Constructors

Constructor and Description
NormalizedLevenshteinDistanceFunction() Deprecated.

Method Summary

Methods

Modifier and Type	Method and Description
DoubleDistance	distance(String o1, String o2) Computes the distance between two given DatabaseObjects according to this distance function.
DoubleDistance	getDistanceFactory() Method to get the distance functions factory.
SimpleTypeInformation<? super String>	getInputTypeRestriction() Get the input data type of the function.

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

instantiate, isMetric, isSymmetric

Methods inherited from class java.lang.Object

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

Field Detail

STATIC_SENSITIVE

public static final NormalizedLevenshteinDistanceFunction STATIC_SENSITIVE

Static instance, case sensitive.

Constructor Detail

NormalizedLevenshteinDistanceFunction

@Deprecated
public NormalizedLevenshteinDistanceFunction()

Deprecated.

Constructor. Use static instance instead.

Method Detail

distance

public DoubleDistance distance(String o1,
                      String o2)

Description copied from interface: PrimitiveDistanceFunction

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

Specified by:

distance in interface PrimitiveDistanceFunction<String,DoubleDistance>

Specified by:

distance in class AbstractPrimitiveDistanceFunction<String,DoubleDistance>

Parameters:

o1 - first DatabaseObject

o2 - second DatabaseObject

Returns:

the distance between two given DatabaseObjects according to this distance function

getDistanceFactory

public DoubleDistance getDistanceFactory()

Description copied from interface: DistanceFunction

Method to get the distance functions factory.

Specified by:

getDistanceFactory in interface DistanceFunction<String,DoubleDistance>

Specified by:

getDistanceFactory in class AbstractPrimitiveDistanceFunction<String,DoubleDistance>

Returns:

Factory for distance objects

getInputTypeRestriction

public SimpleTypeInformation<? super String> getInputTypeRestriction()

Description copied from interface: DistanceFunction

Get the input data type of the function.

Returns:

Type restriction