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
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

Name Description
Nysiis()

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

Properties

Name Description
IsStrict

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

Methods

Name Description
Encode(String)

Encodes a string using the NYSIIS algorithm.
GetNysiis(String)

Retrieves the NYSIIS code for a given string.

Extension Methods

See Also