Package org.apache.commons.text.similarity

Class JaroWinklerSimilarity

java.lang.Object

org.apache.commons.text.similarity.JaroWinklerSimilarity

All Implemented Interfaces:

SimilarityScore<Double>

public class JaroWinklerSimilarity
extends Object
implements SimilarityScore<Double>

A similarity algorithm indicating the percentage of matched characters between two character sequences.

The Jaro measure is the weighted sum of percentage of matched characters from each file and transposed characters. Winkler increased this measure for matching initial characters.

This implementation is based on the Jaro Winkler similarity algorithm from http://en.wikipedia.org/wiki/Jaro%E2%80%93Winkler_distance.

This code has been adapted from Apache Commons Lang 3.3.

Since:

1.7

Constructor Summary

Constructors

Constructor	Description
JaroWinklerSimilarity()

Method Summary

Modifier and Type	Method	Description
Double	apply(CharSequence left, CharSequence right)	Computes the Jaro Winkler Similarity between two character sequences.
protected static int[]	matches(CharSequence first, CharSequence second)	This method returns the Jaro-Winkler string matches, half transpositions, prefix array.

Methods inherited from class java.lang.Object

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

Constructor Detail

JaroWinklerSimilarity

public JaroWinklerSimilarity()

Method Detail

matches

protected static int[] matches(CharSequence first,
                               CharSequence second)

This method returns the Jaro-Winkler string matches, half transpositions, prefix array.

Parameters:

first - the first string to be matched

second - the second string to be matched

Returns:

mtp array containing: matches, half transpositions, and prefix

apply

public Double apply(CharSequence left,
                    CharSequence right)

Computes the Jaro Winkler Similarity between two character sequences.

 sim.apply(null, null)          = IllegalArgumentException
 sim.apply("foo", null)         = IllegalArgumentException
 sim.apply(null, "foo")         = IllegalArgumentException
 sim.apply("", "")              = 1.0
 sim.apply("foo", "foo")        = 1.0
 sim.apply("foo", "foo ")       = 0.94
 sim.apply("foo", "foo  ")      = 0.91
 sim.apply("foo", " foo ")      = 0.87
 sim.apply("foo", "  foo")      = 0.51
 sim.apply("", "a")             = 0.0
 sim.apply("aaapppp", "")       = 0.0
 sim.apply("frog", "fog")       = 0.93
 sim.apply("fly", "ant")        = 0.0
 sim.apply("elephant", "hippo") = 0.44
 sim.apply("hippo", "elephant") = 0.44
 sim.apply("hippo", "zzzzzzzz") = 0.0
 sim.apply("hello", "hallo")    = 0.88
 sim.apply("ABC Corporation", "ABC Corp") = 0.91
 sim.apply("D N H Enterprises Inc", "D & H Enterprises, Inc.") = 0.95
 sim.apply("My Gym Children's Fitness Center", "My Gym. Childrens Fitness") = 0.92
 sim.apply("PENNSYLVANIA", "PENNCISYLVNIA") = 0.88
 

Specified by:

apply in interface SimilarityScore<Double>

Parameters:

left - the first CharSequence, must not be null

right - the second CharSequence, must not be null

Returns:

result similarity

Throws:

IllegalArgumentException - if either CharSequence input is null