Class Nysiis

Encodes a string into a NYSIIS value. NYSIIS is an encoding used to relate similar names, but can also be used as a general purpose scheme to find word with similar phonemes.

Inheritance
System.Object
Nysiis
Implements
Namespace: Lucene.Net.Analysis.Phonetic.Language
Assembly: Lucene.Net.Analysis.Phonetic.dll
Syntax
public class Nysiis : object, IStringEncoder
Remarks

NYSIIS features an accuracy increase of 2.7% over the traditional Soundex algorithm.

Algorithm description:

  1. Transcode first characters of name
    1. MAC -> MCC
    2. KN -> NN
    3. K -> C
    4. PH -> FF
    5. PF -> FF
    6. SCH -> SSS
  2. Transcode last characters of name
    1. EE, IE -> Y
    2. DT,RT,RD,NT,ND -> D
  3. First character of key = first character of name
  4. Transcode remaining characters by following these rules, incrementing by one character each time
    1. EV -> AF else A,E,I,O,U -> A
    2. Q -> G
    3. Z -> S
    4. M -> N
    5. KN -> N else K -> C
    6. SCH -> SSS
    7. PH -> FF
    8. H -> If previous or next is nonvowel, previous
    9. W -> If previous is vowel, previous
    10. Add current to key if current != last key character
  5. If last character is S, remove it
  6. If last characters are AY, replace with Y
  7. If last character is A, remove it
  8. Collapse all strings of repeated characters
  9. Add original first character of name as first character of key

This class is immutable and thread-safe.

See: NYSIIS on Wikipedia

See: NYSIIS on dropby.com

since 1.7

Constructors

| Improve this Doc View Source

Nysiis()

Creates an instance of the Nysiis encoder with strict mode (original form), i.e. encoded strings have a maximum length of 6.

Declaration
public Nysiis()
| Improve this Doc View Source

Nysiis(Boolean)

Create an instance of the Nysiis encoder with the specified strict mode:

  • true:encoded strings have a maximum length of 6
  • false:encoded strings may have arbitrary length

Declaration
public Nysiis(bool strict)
Parameters
Type Name Description
System.Boolean strict

The strict mode.

Properties

| Improve this Doc View Source

IsStrict

Indicates the strict mode for this Nysiis encoder. true if the encoder is configured for strict mode, false otherwise.

Declaration
public virtual bool IsStrict { get; }
Property Value
Type Description
System.Boolean

Methods

| Improve this Doc View Source

Encode(String)

Encodes a string using the NYSIIS algorithm.

Declaration
public virtual string Encode(string str)
Parameters
Type Name Description
System.String str

A string object to encode.
Returns
Type Description
System.String

A Nysiis code corresponding to the string supplied.
| Improve this Doc View Source

GetNysiis(String)

Retrieves the NYSIIS code for a given string.

Declaration
public virtual string GetNysiis(string str)
Parameters
Type Name Description
System.String str

String to encode using the NYSIIS algorithm.
Returns
Type Description
System.String

A NYSIIS code for the string supplied.

Implements

See Also