How to check a partial similarity of two strings in PHP

Question

Is it any function in PHP that check the % of similarity of two strings?

For example i have:

$string1=\"Hello how are you doing\" 
$string2= \" hi,          


        

Answer 1

In addition to Alex Siri's answer and according to the following article:

http://docstore.mik.ua/orelly/webprog/php/ch04_06.htm

PHP provides several functions that let you test whether two strings are approximately equal:

$string1="Hello how are you doing" ;
$string2= " hi, how are you";

SOUNDEX

if (soundex($string1) == soundex($string2)) {

  echo "similar";

} else {

  echo "not similar";

}

METAPHONE

if (metaphone($string1) == metaphone($string2)) {

   echo "similar";

} else {

  echo "not similar";

}

SIMILAR TEXT

$similarity = similar_text($string1, $string2);

LEVENSHTEIN

$distance = levenshtein($string1, $string2);