zintani Posted October 3, 2011 Share Posted October 3, 2011 Hello, Here there is a code to stem words, and the code is called porter stemmer. It is such a rich code, and the problem here I couldn't make it work, i tried to retrieve some information form the database but it didn't work for me. Any help <?php /** * Copyright (c) 2005 Richard Heyes (http://www.phpguru.org/) * * All rights reserved. * * This script is free software. */ /** * PHP5 Implementation of the Porter Stemmer algorithm. Certain elements * were borrowed from the (broken) implementation by Jon Abernathy. * * Usage: * * $stem = PorterStemmer::Stem($word); * * How easy is that? */ class PorterStemmer { /** * Regex for matching a consonant * @var string */ private static $regex_consonant = '(?:[bcdfghjklmnpqrstvwxz]|(?<=[aeiou])y|^y)'; /** * Regex for matching a vowel * @var string */ private static $regex_vowel = '(?:[aeiou]|(?<![aeiou])y)'; /** * Stems a word. Simple huh? * * @param string $word Word to stem * @return string Stemmed word */ public static function Stem($word) { if (strlen($word) <= 2) { print_r($word); } $word = self::step1ab($word); $word = self::step1c($word); $word = self::step2($word); $word = self::step3($word); $word = self::step4($word); $word = self::step5($word); return $word; } Stem("tjhgkbnlk."); /** * Step 1 */ private static function step1ab($word) { // Part a if (substr($word, -1) == 's') { self::replace($word, 'sses', 'ss') OR self::replace($word, 'ies', 'i') OR self::replace($word, 'ss', 'ss') OR self::replace($word, 's', ''); } // Part b if (substr($word, -2, 1) != 'e' OR !self::replace($word, 'eed', 'ee', 0)) { // First rule $v = self::$regex_vowel; // ing and ed if ( preg_match("#$v+#", substr($word, 0, -3)) && self::replace($word, 'ing', '') OR preg_match("#$v+#", substr($word, 0, -2)) && self::replace($word, 'ed', '')) { // Note use of && and OR, for precedence reasons // If one of above two test successful if ( !self::replace($word, 'at', 'ate') AND !self::replace($word, 'bl', 'ble') AND !self::replace($word, 'iz', 'ize')) { // Double consonant ending if ( self::doubleConsonant($word) AND substr($word, -2) != 'll' AND substr($word, -2) != 'ss' AND substr($word, -2) != 'zz') { $word = substr($word, 0, -1); } else if (self::m($word) == 1 AND self::cvc($word)) { $word .= 'e'; } } } } return $word; } /** * Step 1c * * @param string $word Word to stem */ private static function step1c($word) { $v = self::$regex_vowel; if (substr($word, -1) == 'y' && preg_match("#$v+#", substr($word, 0, -1))) { self::replace($word, 'y', 'i'); } return $word; } /** * Step 2 * * @param string $word Word to stem */ private static function step2($word) { switch (substr($word, -2, 1)) { case 'a': self::replace($word, 'ational', 'ate', 0) OR self::replace($word, 'tional', 'tion', 0); break; case 'c': self::replace($word, 'enci', 'ence', 0) OR self::replace($word, 'anci', 'ance', 0); break; case 'e': self::replace($word, 'izer', 'ize', 0); break; case 'g': self::replace($word, 'logi', 'log', 0); break; case 'l': self::replace($word, 'entli', 'ent', 0) OR self::replace($word, 'ousli', 'ous', 0) OR self::replace($word, 'alli', 'al', 0) OR self::replace($word, 'bli', 'ble', 0) OR self::replace($word, 'eli', 'e', 0); break; case 'o': self::replace($word, 'ization', 'ize', 0) OR self::replace($word, 'ation', 'ate', 0) OR self::replace($word, 'ator', 'ate', 0); break; case 's': self::replace($word, 'iveness', 'ive', 0) OR self::replace($word, 'fulness', 'ful', 0) OR self::replace($word, 'ousness', 'ous', 0) OR self::replace($word, 'alism', 'al', 0); break; case 't': self::replace($word, 'biliti', 'ble', 0) OR self::replace($word, 'aliti', 'al', 0) OR self::replace($word, 'iviti', 'ive', 0); break; } return $word; } /** * Step 3 * * @param string $word String to stem */ private static function step3($word) { switch (substr($word, -2, 1)) { case 'a': self::replace($word, 'ical', 'ic', 0); break; case 's': self::replace($word, 'ness', '', 0); break; case 't': self::replace($word, 'icate', 'ic', 0) OR self::replace($word, 'iciti', 'ic', 0); break; case 'u': self::replace($word, 'ful', '', 0); break; case 'v': self::replace($word, 'ative', '', 0); break; case 'z': self::replace($word, 'alize', 'al', 0); break; } return $word; } /** * Step 4 * * @param string $word Word to stem */ private static function step4($word) { switch (substr($word, -2, 1)) { case 'a': self::replace($word, 'al', '', 1); break; case 'c': self::replace($word, 'ance', '', 1) OR self::replace($word, 'ence', '', 1); break; case 'e': self::replace($word, 'er', '', 1); break; case 'i': self::replace($word, 'ic', '', 1); break; case 'l': self::replace($word, 'able', '', 1) OR self::replace($word, 'ible', '', 1); break; case 'n': self::replace($word, 'ant', '', 1) OR self::replace($word, 'ement', '', 1) OR self::replace($word, 'ment', '', 1) OR self::replace($word, 'ent', '', 1); break; case 'o': if (substr($word, -4) == 'tion' OR substr($word, -4) == 'sion') { self::replace($word, 'ion', '', 1); } else { self::replace($word, 'ou', '', 1); } break; case 's': self::replace($word, 'ism', '', 1); break; case 't': self::replace($word, 'ate', '', 1) OR self::replace($word, 'iti', '', 1); break; case 'u': self::replace($word, 'ous', '', 1); break; case 'v': self::replace($word, 'ive', '', 1); break; case 'z': self::replace($word, 'ize', '', 1); break; } return $word; } /** * Step 5 * * @param string $word Word to stem */ private static function step5($word) { // Part a if (substr($word, -1) == 'e') { if (self::m(substr($word, 0, -1)) > 1) { self::replace($word, 'e', ''); } else if (self::m(substr($word, 0, -1)) == 1) { if (!self::cvc(substr($word, 0, -1))) { self::replace($word, 'e', ''); } } } // Part b if (self::m($word) > 1 AND self::doubleConsonant($word) AND substr($word, -1) == 'l') { $word = substr($word, 0, -1); } return $word; } /** * Replaces the first string with the second, at the end of the string. If third * arg is given, then the preceding string must match that m count at least. * * @param string $str String to check * @param string $check Ending to check for * @param string $repl Replacement string * @param int $m Optional minimum number of m() to meet * @return bool Whether the $check string was at the end * of the $str string. True does not necessarily mean * that it was replaced. */ private static function replace(&$str, $check, $repl, $m = null) { $len = 0 - strlen($check); if (substr($str, $len) == $check) { $substr = substr($str, 0, $len); if (is_null($m) OR self::m($substr) > $m) { $str = $substr . $repl; } return true; } return false; } /** * What, you mean it's not obvious from the name? * * m() measures the number of consonant sequences in $str. if c is * a consonant sequence and v a vowel sequence, and <..> indicates arbitrary * presence, * * <c><v> gives 0 * <c>vc<v> gives 1 * <c>vcvc<v> gives 2 * <c>vcvcvc<v> gives 3 * * @param string $str The string to return the m count for * @return int The m count */ private static function m($str) { $c = self::$regex_consonant; $v = self::$regex_vowel; $str = preg_replace("#^$c+#", '', $str); $str = preg_replace("#$v+$#", '', $str); preg_match_all("#($v+$c+)#", $str, $matches); return count($matches[1]); } /** * Returns true/false as to whether the given string contains two * of the same consonant next to each other at the end of the string. * * @param string $str String to check * @return bool Result */ private static function doubleConsonant($str) { $c = self::$regex_consonant; return preg_match("#$c{2}$#", $str, $matches) AND $matches[0]{0} == $matches[0]{1}; } /** * Checks for ending CVC sequence where second C is not W, X or Y * * @param string $str String to check * @return bool Result */ private static function cvc($str) { $c = self::$regex_consonant; $v = self::$regex_vowel; return preg_match("#($c$v$c)$#", $str, $matches) AND strlen($matches[1]) == 3 AND $matches[1]{2} != 'w' AND $matches[1]{2} != 'x' AND $matches[1]{2} != 'y'; } } ?> Quote Link to comment Share on other sites More sharing options...
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