php-string-compare
This class compares two strings and outputs the similarities/difference as percentage
Usage:
$string1 = 'This is my test string';
$string2 = 'This is my second text string';
require('string_compare.inc.php');
$phpStringCompare = new StringCompare($string1, $string2,
array('remove_html_tags'=>false, 'remove_extra_spaces'=>true,
'remove_punctuation'=>true, 'punctuation_symbols'=>Array('.', ','))
);
$percent = $phpStringCompare->getSimilarityPercentage();
$percent2 = $phpStringCompare->getDifferencePercentage();
echo $string1.' and '.$string2 are '.$percent.'% similar and '.$percent2.'% differnt';