soundex
(PHP 4, PHP 5, PHP 7, PHP 8)
soundex — Calculate the soundex key of a string
Description
$string): string
Calculates the soundex key of string.
Soundex keys have the property that words pronounced similarly produce the same soundex key, and can thus be used to simplify searches in databases where you know the pronunciation but not the spelling.
This particular soundex function is one described by Donald Knuth in "The Art Of Computer Programming, vol. 3: Sorting And Searching", Addison-Wesley (1973), pp. 391-392.
Parameters
-
string -
The input string.
Return Values
Returns the soundex key as a string with four characters.
If at least one letter is contained in string, the returned
string starts with a letter. Otherwise "0000" is returned.
Changelog
| Version | Description |
|---|---|
| 8.0.0 |
Prior to this version, calling the function with an empty string returned false
for no particular reason.
|
Examples
Example #1 Soundex Examples
<?php
soundex("Euler") == soundex("Ellery"); // E460
soundex("Gauss") == soundex("Ghosh"); // G200
soundex("Hilbert") == soundex("Heilbronn"); // H416
soundex("Knuth") == soundex("Kant"); // K530
soundex("Lloyd") == soundex("Ladd"); // L300
soundex("Lukasiewicz") == soundex("Lissajous"); // L222
?>
See Also
- levenshtein() - Calculate Levenshtein distance between two strings
- metaphone() - Calculate the metaphone key of a string
- similar_text() - Calculate the similarity between two strings
