<?php
/**
* SeekQuarry/Yioop --
* Open Source Pure PHP Search Engine, Crawler, and Indexer
*
* Copyright (C) 2009 - 2026 Chris Pollett chris@pollett.org
*
* LICENSE:
*
* This program is free software: you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation, either version 3 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program. If not, see <https://www.gnu.org/licenses/>.
*
* @author Chris Pollett chris@pollett.org
* @license https://www.gnu.org/licenses/ GPL3
* @link https://www.seekquarry.com/
* @copyright 2009 - 2026
* @filesource
*/
namespace seekquarry\yioop\locale\fr_FR\resources;
use seekquarry\yioop\library as L;
/**
* This class has a collection of methods for French locale specific
* tokenization. In particular, it has a stemmer, a stop word remover (for
* use mainly in word cloud creation). The stemmer is my stab at re-implementing
* the stemmer algorithm given at http://snowball.tartarus.org and was
* inspired by http://snowball.tartarus.org/otherlangs/french_javascript.txt
* Here given a word, its stem is that part of the word that
* is common to all its inflected variants. For example,
* tall is common to tall, taller, tallest. A stemmer takes
* a word and tries to produce its stem.
*
* @author Chris Pollett
*/
class Tokenizer
{
/**
* Words we don't want to be stemmed
* @var array
*/
public static $no_stem_list = ["titanic"];
/**
* A list of frequently occurring terms for this locale which should
* be excluded from certain kinds of queries
* @var array
*/
public static $stop_words =
['alors', 'au', 'aucuns', 'aussi', 'autre', 'avant',
'avec', 'avoir', 'bon', 'car', 'ce', 'cela', 'ces', 'ceux',
'chaque', 'ci', 'comme', 'comment', 'dans', 'des', 'du', 'dedans',
'dehors', 'depuis', 'deux', 'devrait', 'doit', 'donc', 'dos',
'droite', 'début', 'elle', 'elles', 'en', 'encore', 'essai', 'est',
'et', 'eu', 'fait', 'faites', 'fois', 'font', 'force', 'haut',
'hors', 'http', 'https', 'ici', 'il', 'ils', 'je', 'juste', 'la',
'le', 'les','leur',
'là', 'ma', 'maintenant', 'mais', 'mes', 'mine', 'moins', 'mon',
'mot', 'même', 'ni', 'nommés', 'notre', 'nous', 'nouveaux', 'ou',
'où', 'par', 'parce', 'parole', 'pas', 'personnes', 'peut', 'peu',
'pièce', 'plupart', 'pour', 'pourquoi', 'quand', 'que', 'quel',
'quelle', 'quelles', 'quels', 'qui', 'sa', 'sans', 'ses',
'seulement', 'si', 'sien', 'son', 'sont', 'sous', 'soyez', 'sujet',
'sur', 'ta', 'tandis', 'tellement', 'tels', 'tes', 'ton', 'tous',
'tout', 'trop', 'très', 'tu','valeur', 'voie', 'voient', 'vont',
'votre','vous','vu','ça','étaient', 'état', 'étions', 'été',
'être'];
/**
* French vowels
* @var string
*/
private static $vowel = 'aeiouyàâëéèêïîôûù';
/**
* Storage used in computing the stem
* @var string
*/
private static $buffer;
/**
* $rv is approximately the string after the first vowel in the $word we
* want to stem
* @var string
*/
private static $rv;
/**
* Position in $word to stem of $rv
* @var int
*/
private static $rv_index;
/**
* $r1 is the region after the first non-vowel following a vowel, or the end
* of the word if there is no such non-vowel.
* @var string
*/
private static $r1;
/**
* Position in $word to stem of $r1
* @var int
*/
private static $r1_index;
/**
* $r2 is the region after the first non-vowel following a vowel in $r1, or
* the end of the word if there is no such non-vowel
* @var string
*/
private static $r2;
/**
* Position in $word to stem of $r2
* @var int
*/
private static $r2_index;
/**
* Stub function which could be used for a word segmenter.
* Such a segmenter on input thisisabunchofwords would output
* this is a bunch of words
*
* @param string $pre_segment before segmentation
* @return string should return string with words separated by space
* in this case does nothing
*/
public static function segment($pre_segment)
{
return $pre_segment;
}
/**
* Removes the stop words from the page (used for Word Cloud generation)
*
* @param mixed $data either a string or an array of string to remove
* stop words from
* @return mixed $data with no stop words
*/
public static function stopwordsRemover($data)
{
static $pattern = "";
if (empty($pattern)) {
$pattern = '/\b(' . implode('|', self::$stop_words) . ')\b/u';
}
$data = preg_replace($pattern, '', $data);
return $data;
}
/**
* Computes the stem of a French word
*
* @param string $word the string to stem
* @return string the stem of $words
*/
public static function stem($word)
{
if (in_array($word, self::$no_stem_list)) {
return $word;
}
$before_process = mb_strtolower($word, "UTF-8");
self::$buffer = $before_process;
self::computeNonVowels();
self::computeNonVowelRegions();
self::step1(); //suffix removal
$word_step1 = self::$buffer;
if (self::step2a($before_process) //verb suffixes beginning with i
&& $word_step1 == self::$buffer) {
self::step2b(); //other verb suffixes
}
if (mb_strtolower(self::$buffer, "UTF-8") != $before_process) {
self::step3();
} else {
self::step4();
}
self::step5(); //un-double
self::step6(); //un-accent
self::$buffer = mb_strtolower(self::$buffer, "UTF-8");
return self::$buffer;
}
/**
* If a vowel shouldn't be treated as a volume it is capitalized by
* this method. (Operations done on buffer.)
*/
private static function computeNonVowels()
{
$vowel = static::$vowel;
self::$buffer = preg_replace("/qu/u", "qU", self::$buffer);
self::$buffer = preg_replace("/([$vowel])y/u", '$1Y',
self::$buffer);
self::$buffer = preg_replace("/y([$vowel])/u", 'Y$1',
self::$buffer);
self::$buffer = preg_replace("/([$vowel])u([$vowel])/u", '$1U$2',
self::$buffer);
self::$buffer = preg_replace("/([$vowel])i([$vowel])/u", '$1I$2',
self::$buffer);
}
/**
* $r1 is the region after the first non-vowel following a vowel, or the end
* of the word if there is no such non-vowel.
* $r2 is the region after the first non-vowel following a vowel in $r1, or
* the end of the word if there is no such non-vowel
*/
private static function computeNonVowelRegions()
{
$word = self::$buffer;
$vowel = static::$vowel;
self::$rv = "";
self::$rv_index = -1;
if (L\preg_search('/^(par|col|tap)/u', $word) != -1 ||
L\preg_search("/^[$vowel]{2}/u", $word) != -1) {
self::$rv = substr($word, 3);
self::$rv_index = 3;
} else {
self::$rv_index = L\preg_search("/[$vowel]/u", $word,
strlen(mb_substr($word, 0, 1, 'UTF-8')));
if (self::$rv_index != -1){
self::$rv_index += 1;
self::$rv = substr($word, self::$rv_index);
} else {
self::$rv_index = strlen($word);
}
}
preg_match("/[$vowel][^$vowel]/u", $word, $matches,
PREG_OFFSET_CAPTURE);
self::$r1 = "";
$len = strlen($word);
self::$r1_index = isset($matches[0][1]) ? $matches[0][1] +
strlen(mb_substr($word,$matches[0][1], 2, 'UTF-8')) : $len;
if (self::$r1_index != $len) {
self::$r1 = substr($word, self::$r1_index);
}
if (self::$r1_index != $len) {
preg_match("/[$vowel][^$vowel]/", self::$r1, $matches,
PREG_OFFSET_CAPTURE);
self::$r2_index = isset($matches[0][1]) ? $matches[0][1] +
strlen(mb_substr(self::$r1, $matches[0][1], 2, 'UTF-8')) : $len;
if (self::$r2_index != $len) {
self::$r2 = substr(self::$r1, self::$r2_index);
self::$r2_index += self::$r1_index;
}
}
if (self::$r1_index != $len && self::$r1_index < 3) {
self::$r1_index = 3;
self::$r1 = substr($word, 3);
}
}
/**
* Standard suffix removal
*/
private static function step1()
{
$word = self::$buffer;
$vowel = static::$vowel;
$rv_index = self::$rv_index;
$r1_index = self::$r1_index;
$r2_index = self::$r2_index;
$a_index = [];
$patterns = ['/(ance|iqUe|isme|able|iste|eux|'.
'ances|iqUes|ismes|ables|istes)$/u',
'/(atrice|ateur|ation|atrices|ateurs|ations)$/u',
'/(logie|logies)$/u', '/(usion|ution|usions|utions)$/u',
'/(ence|ences)$/u', '/(ement|ements)$/u', '/(ité|ités)$/u',
'/(if|ive|ifs|ives)$/u', '/(eaux)$/u', '/(aux)$/u',
'/(euse|euses)$/u',
"/[^$vowel](issement|issements)".'$/u', '/(amment)$/u',
'/(emment)$/u', "/[$vowel]".'(ment|ments)$/u'];
$i = 1;
foreach ($patterns as $pattern) {
$a_index[$i] = L\preg_search($pattern, $word);
$i++;
}
if ($a_index[1] != -1 && $a_index[1] >= $r2_index) {
$word = substr($word, 0, $a_index[1]);
} else if ($a_index[2] != -1 && $a_index[2] >= $r2_index) {
$word = substr($word, 0, $a_index[2]);
$a2_index2 = L\preg_search('/(ic)$/', $word);
if ($a2_index2 != -1 && $a2_index2 >= $r2_index){
$word = substr($word, 0, $a2_index2);
//if preceded by ic, delete if in R2,
} else { //else replace by iqU
$word = preg_replace('/(ic)$/u','iqU', $word);
}
} else if ($a_index[3] != -1 && $a_index[3] >= $r2_index) {
//replace with log if in R2
$word = preg_replace('/(logie|logies)$/','log', $word);
} else if ($a_index[4] != -1 && $a_index[4] >= $r2_index){
//replace with u if in R2
$word = preg_replace('/(usion|ution|usions|utions)$/u','u', $word);
} else if ($a_index[5] != -1 && $a_index[5] >= $r2_index) {
//replace with ent if in R2
$word = preg_replace('/(ence|ences)$/u','ent', $word);
} else if ($a_index[12] != -1 && $a_index[12] >= $r1_index) {
//+1- amendment to non-vowel
$word = substr($word, 0, $a_index[12] + 1);
} else if ($a_index[6] != -1 && $a_index[6] >= $rv_index) {
if (L\preg_search("/(issement|issements)$/", $word) < 0) {
$word = substr($word, 0, $a_index[6]);
if (L\preg_search('/(iv)$/', $word) >= $r2_index) {
$word = preg_replace('/(iv)$/u', '', $word);
if (L\preg_search('/(at)$/', $word) >= $r2_index){
$word = preg_replace('/(at)$/u', '', $word);
}
} else if (
($a6_index2 = L\preg_search('/(eus)$/u', $word)) != -1) {
if ($a6_index2 >= $r2_index) {
$word = substr($word, 0, $a6_index2);
} else if ($a6_index2 >= $r1_index){
$word = substr($word, 0, $a6_index2) . "eux";
}
} else if (L\preg_search('/(abl|iqU)$/', $word) >= $r2_index) {
//if preceded by abl or iqU, delete if in R2,
$word = preg_replace('/(abl|iqU)$/u', '', $word);
} else if (L\preg_search('/(ièr|Ièr)$/', $word) >= $rv_index) {
//if preceded by abl or iqU, delete if in R2,
$word = preg_replace('/(ièr|Ièr)$/u', 'i', $word);
}
} else if (L\preg_search("/[^$vowel](issement|issements)".'$/u',
$word) > 0) {
$word = preg_replace("/(issement|issements)".'$/u',
'', $word);
}
} else if ($a_index[7] != -1 && $a_index[7] >= $r2_index) {
//delete if in R2
$word = substr($word, 0, $a_index[7]);
/*if preceded by abil, delete if in R2, else replace by abl,
otherwise,
*/
if (($a7_index2 = L\preg_search('/(abil)$/', $word)) != -1) {
if ($a7_index2 >= $r2_index){
$word = substr($word, 0, $a7_index2);
} else {
$word = substr($word, 0, $a7_index2) . "abl";
}
} else if (($a7_index3 = L\preg_search('/(ic)$/', $word)) != -1) {
if ($a7_index3 >= $r2_index) {
//if preceded by ic, delete if in R2,
$word = substr($word, 0, $a7_index3);
} else {
//else replace by iqU
$word = preg_replace('/(ic)$/u', 'iqU', $word);
}
} else if (L\preg_search('/(iv)$/', $word) >= $r2_index){
$word = preg_replace('/(iv)$/u', '', $word);
}
} else if ($a_index[8] != -1 && $a_index[8] >= $r2_index) {
$word = substr($word, 0, $a_index[8]);
if (L\preg_search('/(at)$/', $word) >= $r2_index) {
$word = preg_replace('/(at)$/', '', $word);
if (L\preg_search('/(ic)$/', $word) >= $r2_index) {
$word = preg_replace('/(ic)$/u', '', $word);
} else {
$word = preg_replace('/(ic)$/u', 'iqU', $word);
}
}
} else if ($a_index[9] != -1) {
$word = preg_replace('/(eaux)/u', 'eau', $word);
} else if ($a_index[10] >= $r1_index) {
$word = preg_replace('/(aux)/u', 'al', $word);
} else if ($a_index[11] != -1 ){
$a11_index2 = L\preg_search('/(euse|euses)$/u', $word);
if ($a11_index2 >= $r2_index){
$word = substr($word, 0, $a11_index2);
} else if ($a11_index2 >= $r1_index){
$word = substr($word, 0, $a11_index2) . "eux";
}
} else if ($a_index[13] != -1 && $a_index[13] >= $rv_index) {
$word = preg_replace('/(amment)$/u', 'ant', $word);
} else if ($a_index[14] != -1 && $a_index[14] >= $rv_index) {
$word = preg_replace('/(emment)$/u','ent', $word);
} else if ($a_index[15] != -1 && $a_index[15] >= $rv_index &&
$a_index[6] < 0) {
$tmp_index = L\preg_search('/(ment|ments)$/u', $word);
$word = substr($word, 0, $tmp_index);
}
self::$buffer = $word;
}
/**
* Stem verb suffixes beginning i
* @param string $ori_word original word before stemming
* @return bool true when the i-prefixed verb-suffix rule fired and
* self::$buffer was rewritten; false when the rule did not apply
*/
private static function step2a($ori_word)
{
$vowel = static::$vowel;
if ($ori_word == mb_strtolower(self::$buffer, "UTF-8") ||
(preg_match('/(amment|emment|ment|ments)$/u', $ori_word)
&& !preg_match('/(ement(s)?)$/u', $ori_word))) {
$b1_regex = "/([^$vowel])".'(îmes|ît|îtes|i|ie|ies|ir|ira|irai|'.
'iraIent|irais|irait|iras|irent|irez|iriez|irions|irons|'.
'iront|is|issaIent|issais|issait|issant|issante|issantes|'.
'issants|isse|issent|isses|issez|issiez|issions|issons|it)$/u';
if (L\preg_search($b1_regex, self::$buffer) >= self::$rv_index) {
self::$buffer = preg_replace($b1_regex, '$1', self::$buffer);
}
return true;
}
return false;
}
/**
* Stem other verb suffixes
*/
private static function step2b()
{
$word = self::$buffer;
if (L\preg_search('/(ions)$/u', $word) >= self::$r2_index &&
L\preg_search('/erions$/u', $word) == -1) {
$word = preg_replace('/(ions)$/u', '', $word);
} else {
$b2_regex = '/(é|ée|ées|és|èrent|er|' .
'era|erai|eraIent|erais|erait|'.
'eras|erez|eriez|erions|erons|eront|iez)$/u';
if (L\preg_search($b2_regex, $word) >= self::$rv_index) {
$word = preg_replace($b2_regex, '', $word);
} else if (L\preg_search('/iez$/iu', $word) >= self::$rv_index) {
//I am trying to avoid issues that eriez is a prefix of eriez
$word = preg_replace('/iez$/iu', '', $word);
} else if (L\preg_search('/ez$/iu', $word) >= self::$rv_index) {
//I am trying to avoid issues that ez is a prefix of iez
$word = preg_replace('/ez$/iu', '', $word);
} else {
$b3_regex = '/e(âmes|ât|âtes|a|ai|aIent|' .
'ais|ait|ant|ante|antes' .
'|ants|as|asse|assent|asses|assiez|assions)$/u';
if (L\preg_search($b3_regex, $word) >= self::$rv_index) {
$word = preg_replace($b3_regex, '', $word);
} else {
$b3_regex2 = '/(âmes|ât|âtes|a|ai|aIent|' .
'ais|ait|ant|ante|'.
'antes|ants|as|asse|assent|asses|assiez|assions)$/u';
if (L\preg_search($b3_regex2, $word) >= self::$rv_index) {
$word = preg_replace($b3_regex2, '', $word);
}
}
}
}
self::$buffer = $word;
}
/**
* Gets rid of cedille's (make c's) and words ending with Y (make i)
*/
private static function step3()
{
$word = self::$buffer;
$word = preg_replace('/Y$/u', 'i', $word);
$word = preg_replace('/ç$/u', 'c', $word);
self::$buffer = $word;
}
/**
* If the word ends in an s, not preceded by a, i, o, u, è or s, delete it.
*/
private static function step4()
{
$word = self::$buffer;
if (L\preg_search('/([^aiouès])s$/u', $word) >= 0) {
$word = preg_replace('/([^aiouès])s$/u', '$1', $word);
}
$e1_index = L\preg_search('/ion$/u', $word);
if ($e1_index >= self::$r2_index &&
L\preg_search('/[st]ion$/u', $word) >= self::$rv_index) {
$word = substr($word, 0, $e1_index);
} else {
$e2_index = L\preg_search('/(ier|ière|Ier|Ière)$/u', $word);
if ($e2_index != -1 && $e2_index >= self::$rv_index) {
$word = substr($word, 0, $e2_index)."i";
} else {
if (L\preg_search('/e$/u', $word) >= self::$rv_index) {
$word = preg_replace('/e$/u', '', $word); //delete last e
} else if (L\preg_search('/guë$/u', $word) >= self::$rv_index) {
$word = preg_replace('/guë$/u', 'gu', $word);
}
}
}
self::$buffer = $word;
}
/**
* Un-double letter end
*/
private static function step5()
{
self::$buffer = preg_replace("/(en|on)(n)$/u", '$1',
self::$buffer);
self::$buffer = preg_replace("/(ett)$/u", 'et',
self::$buffer);
self::$buffer = preg_replace("/(el|eil)(l)$/u", '$1',
self::$buffer);
}
/**
* Un-accent end
*/
private static function step6()
{
$vowel = static::$vowel;
self::$buffer = preg_replace("/[éè]([^$vowel]+)$/u", 'e$1',
self::$buffer);
self:$buffer = mb_strtolower(self::$buffer);
}
}
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