PHP soundex() Function
The soundex() function is a built-in function in PHP and is used to calculate the Soundex key of a given string. The soundex key is a four character long alphanumeric string(starting with a letter) which represents the English pronunciation of the given string.
Syntax:
string soundex($str);
Parameters: This function accepts a single parameter $str which represents the string for which we want to find the Soundex key.
Return Value: It returns the soundex key as a string.
Below programs illustrate the soundex() function in PHP:
Program 1: In the below program, the soundex() function generates the soundex key of the string "geeksforgeeks".
<?php
$str = "geeksforgeeks";
echo soundex($str);
?>
Output:
G216
Program 2: In the below program, we will see that two words having same pronunciation produce similar Soundex key.
<?php
$str1 = "hair";
$str2 = "heir";
echo soundex($str1)."\n";
echo soundex($str2);
?>
Output:
H600 H600
Reference: https://www.php.net/manual/en/function.soundex.php