Class NGramDistance

N-Gram version of edit distance based on paper by Grzegorz Kondrak, "N-gram similarity and distance". Proceedings of the Twelfth International Conference on String Processing and Information Retrieval (SPIRE 2005), pp. 115-126, Buenos Aires, Argentina, November 2005. http://www.cs.ualberta.ca/~kondrak/papers/spire05.pdf

This implementation uses the position-based optimization to compute partial matches of n-gram sub-strings and adds a null-character prefix of size n-1 so that the first character is contained in the same number of n-grams as a middle character. Null-character prefix matches are discounted so that strings with no matching characters will return a distance of 0.

Inheritance

System.Object

NGramDistance

Implements

IStringDistance

Namespace: Lucene.Net.Search.Spell

Assembly: Lucene.Net.Suggest.dll

Syntax

public class NGramDistance : object, IStringDistance

Constructors

NGramDistance()

Creates an N-Gram distance measure using n-grams of size 2.

Declaration

public NGramDistance()

NGramDistance(Int32)

Creates an N-Gram distance measure using n-grams of the specified size.

Declaration

public NGramDistance(int size)

Parameters

Type	Name	Description
System.Int32	size	The size of the n-gram to be used to compute the string distance.

Methods

Equals(Object)

Declaration

public override bool Equals(object obj)

Parameters

Type	Name	Description
System.Object	obj

Returns

Type	Description
System.Boolean

GetDistance(String, String)

Declaration

public virtual float GetDistance(string source, string target)

Parameters

Type	Name	Description
System.String	source
System.String	target

Returns

Type	Description
System.Single

GetHashCode()

Declaration

public override int GetHashCode()

Returns

Type	Description
System.Int32

ToString()

Declaration

public override string ToString()

Returns

Type	Description
System.String

Implements

IStringDistance