Class WeightedLevenshtein

java.lang.Object

info.debatty.java.stringsimilarity.WeightedLevenshtein

All Implemented Interfaces:

StringDistance, Serializable

@Immutable
public class WeightedLevenshtein
extends Object
implements StringDistance

Implementation of Levenshtein that allows to define different weights for different character substitutions.

See Also:

• Serialized Form

Field Summary

Fields

Modifier and Type	Field	Description
private final CharacterInsDelInterface	charchange
private final CharacterSubstitutionInterface	charsub

Constructor Summary

Constructors

Constructor	Description
WeightedLevenshtein(CharacterSubstitutionInterface charsub)	Instantiate with provided character substitution.
WeightedLevenshtein(CharacterSubstitutionInterface charsub, CharacterInsDelInterface charchange)	Instantiate with provided character substitution, insertion, and deletion weights.

Method Summary

Modifier and Type	Method	Description
private double	deletionCost(char c)
final double	distance(String s1, String s2)	Equivalent to distance(s1, s2, Double.MAX_VALUE).
final double	distance(String s1, String s2, double limit)	Compute Levenshtein distance using provided weights for substitution.
private double	insertionCost(char c)

Methods inherited from class Object

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

Field Details

charsub

private final CharacterSubstitutionInterface charsub

charchange

private final CharacterInsDelInterface charchange

Constructor Details

WeightedLevenshtein

public WeightedLevenshtein(CharacterSubstitutionInterface charsub)

Instantiate with provided character substitution.

Parameters:

charsub - The strategy to determine character substitution weights.

WeightedLevenshtein

public WeightedLevenshtein(CharacterSubstitutionInterface charsub,
 CharacterInsDelInterface charchange)

Instantiate with provided character substitution, insertion, and deletion weights.

Parameters:

charsub - The strategy to determine character substitution weights.

charchange - The strategy to determine character insertion / deletion weights.

Method Details

distance

public final double distance(String s1,
 String s2)

Equivalent to distance(s1, s2, Double.MAX_VALUE).

Specified by:

distance in interface StringDistance

Parameters:

s1 -

s2 -

Returns:

distance

public final double distance(String s1,
 String s2,
 double limit)

Compute Levenshtein distance using provided weights for substitution.

Parameters:

s1 - The first string to compare.

s2 - The second string to compare.

limit - The maximum result to compute before stopping. This means that the calculation can terminate early if you only care about strings with a certain similarity. Set this to Double.MAX_VALUE if you want to run the calculation to completion in every case.

Returns:

The computed weighted Levenshtein distance.

Throws:

NullPointerException - if s1 or s2 is null.

insertionCost

private double insertionCost(char c)

deletionCost

private double deletionCost(char c)