info.debatty.java.stringsimilarity

Class Damerau

java.lang.Object

info.debatty.java.stringsimilarity.Damerau

All Implemented Interfaces:

MetricStringDistance, StringDistance, Serializable

@Immutable
public class Damerau
extends Object
implements MetricStringDistance

Implementation of Damerau-Levenshtein distance with transposition (also sometimes calls unrestricted Damerau-Levenshtein distance). It is the minimum number of operations needed to transform one string into the other, where an operation is defined as an insertion, deletion, or substitution of a single character, or a transposition of two adjacent characters. It does respect triangle inequality, and is thus a metric distance. This is not to be confused with the optimal string alignment distance, which is an extension where no substring can be edited more than once.

Author:

Thibault Debatty

See Also:

Serialized Form

Constructor Summary

Constructors

Constructor and Description
Damerau()

Method Summary

Modifier and Type	Method and Description
double	distance(String s1, String s2) Compute the distance between strings: the minimum number of operations needed to transform one string into the other (insertion, deletion, substitution of a single character, or a transposition of two adjacent characters).

Methods inherited from class java.lang.Object

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

Constructor Detail

Damerau

public Damerau()

Method Detail

distance

public final double distance(String s1,
                             String s2)

Compute the distance between strings: the minimum number of operations needed to transform one string into the other (insertion, deletion, substitution of a single character, or a transposition of two adjacent characters).

Specified by:

distance in interface MetricStringDistance

Specified by:

distance in interface StringDistance

Parameters:

s1 - The first string to compare.

s2 - The second string to compare.

Returns:

The computed distance.

Throws:

NullPointerException - if s1 or s2 is null.