public function stem($word)
{
$len = strlen($word);
if ($len <= 2) {
return $word;
}
//$word = lower_case($word);
$r1 = $r2 = $rv = $len;
//R1 is the region after the first non-vowel following a vowel, or is the null region at the end of the word if there is no such non-vowel.
for ($i = 0; $i < $len - 1 && $r1 == $len; $i++) {
if (es_stemmer::is_vowel($word[$i]) && !es_stemmer::is_vowel($word[$i + 1])) {
$r1 = $i + 2;
}
}
//R2 is the region after the first non-vowel following a vowel in R1, or is the null region at the end of the word if there is no such non-vowel.
for ($i = $r1; $i < $len - 1 && $r2 == $len; $i++) {
if (es_stemmer::is_vowel($word[$i]) && !es_stemmer::is_vowel($word[$i + 1])) {
$r2 = $i + 2;
}
}
if ($len > 3) {
if (!es_stemmer::is_vowel($word[1])) {
// If the second letter is a consonant, RV is the region after the next following vowel
$rv = es_stemmer::getNextVowelPos($word, 2) + 1;
} elseif (es_stemmer::is_vowel($word[0]) && es_stemmer::is_vowel($word[1])) {
// or if the first two letters are vowels, RV is the region after the next consonant
$rv = es_stemmer::getNextConsonantPos($word, 2) + 1;
} else {
//otherwise (consonant-vowel case) RV is the region after the third letter. But RV is the end of the word if these positions cannot be found.
$rv = 3;
}
}
$r1_txt = substr($word, $r1);
$r2_txt = substr($word, $r2);
$rv_txt = substr($word, $rv);
$word_orig = $word;
// Step 0: Attached pronoun
$pronoun_suf = array('me', 'se', 'sela', 'selo', 'selas', 'selos', 'la', 'le', 'lo', 'las', 'les', 'los', 'nos');
$pronoun_suf_pre1 = array('éndo', 'ándo', 'ár', 'ér', 'ír');
$pronoun_suf_pre2 = array('ando', 'iendo', 'ar', 'er', 'ir');
$suf = es_stemmer::endsinArr($word, $pronoun_suf);
if ($suf != '') {
$pre_suff = es_stemmer::endsinArr(substr($rv_txt, 0, -strlen($suf)), $pronoun_suf_pre1);
if ($pre_suff != '') {
$word = es_stemmer::removeAccent(substr($word, 0, -strlen($suf)));
} else {
$pre_suff = es_stemmer::endsinArr(substr($rv_txt, 0, -strlen($suf)), $pronoun_suf_pre2);
if ($pre_suff != '' || es_stemmer::endsin($word, 'yendo') && substr($word, -strlen($suf) - 6, 1) == 'u') {
$word = substr($word, 0, -strlen($suf));
}
}
}
if ($word != $word_orig) {
$r1_txt = substr($word, $r1);
$r2_txt = substr($word, $r2);
$rv_txt = substr($word, $rv);
}
$word_after0 = $word;
if (($suf = es_stemmer::endsinArr($r2_txt, array('anza', 'anzas', 'ico', 'ica', 'icos', 'icas', 'ismo', 'ismos', 'able', 'ables', 'ible', 'ibles', 'ista', 'istas', 'oso', 'osa', 'osos', 'osas', 'amiento', 'amientos', 'imiento', 'imientos'))) != '') {
$word = substr($word, 0, -strlen($suf));
} elseif (($suf = es_stemmer::endsinArr($r2_txt, array('icadora', 'icador', 'icación', 'icadoras', 'icadores', 'icaciones', 'icante', 'icantes', 'icancia', 'icancias', 'adora', 'ador', 'ación', 'adoras', 'adores', 'aciones', 'ante', 'antes', 'ancia', 'ancias'))) != '') {
$word = substr($word, 0, -strlen($suf));
} elseif (($suf = es_stemmer::endsinArr($r2_txt, array('logía', 'logías'))) != '') {
$word = substr($word, 0, -strlen($suf)) . 'log';
} elseif (($suf = es_stemmer::endsinArr($r2_txt, array('ución', 'uciones'))) != '') {
$word = substr($word, 0, -strlen($suf)) . 'u';
} elseif (($suf = es_stemmer::endsinArr($r2_txt, array('encia', 'encias'))) != '') {
$word = substr($word, 0, -strlen($suf)) . 'ente';
} elseif (($suf = es_stemmer::endsinArr($r2_txt, array('ativamente', 'ivamente', 'osamente', 'icamente', 'adamente'))) != '') {
$word = substr($word, 0, -strlen($suf));
} elseif (($suf = es_stemmer::endsinArr($r1_txt, array('amente'))) != '') {
$word = substr($word, 0, -strlen($suf));
} elseif (($suf = es_stemmer::endsinArr($r2_txt, array('antemente', 'ablemente', 'iblemente', 'mente'))) != '') {
$word = substr($word, 0, -strlen($suf));
} elseif (($suf = es_stemmer::endsinArr($r2_txt, array('abilidad', 'abilidades', 'icidad', 'icidades', 'ividad', 'ividades', 'idad', 'idades'))) != '') {
$word = substr($word, 0, -strlen($suf));
} elseif (($suf = es_stemmer::endsinArr($r2_txt, array('ativa', 'ativo', 'ativas', 'ativos', 'iva', 'ivo', 'ivas', 'ivos'))) != '') {
$word = substr($word, 0, -strlen($suf));
}
if ($word != $word_after0) {
$r1_txt = substr($word, $r1);
$r2_txt = substr($word, $r2);
$rv_txt = substr($word, $rv);
}
$word_after1 = $word;
if ($word_after0 == $word_after1) {
// Do step 2a if no ending was removed by step 1.
if (($suf = es_stemmer::endsinArr($rv_txt, array('ya', 'ye', 'yan', 'yen', 'yeron', 'yendo', 'yo', 'yó', 'yas', 'yes', 'yais', 'yamos'))) != '' && substr($word, -strlen($suf) - 1, 1) == 'u') {
$word = substr($word, 0, -strlen($suf));
}
if ($word != $word_after1) {
$r1_txt = substr($word, $r1);
$r2_txt = substr($word, $r2);
$rv_txt = substr($word, $rv);
}
$word_after2a = $word;
// Do Step 2b if step 2a was done, but failed to remove a suffix.
if ($word_after2a == $word_after1) {
if (($suf = es_stemmer::endsinArr($rv_txt, array('en', 'es', 'éis', 'emos'))) != '') {
$word = substr($word, 0, -strlen($suf));
if (es_stemmer::endsin($word, 'gu')) {
$word = substr($word, 0, -1);
}
} elseif (($suf = es_stemmer::endsinArr($rv_txt, array('arían', 'arías', 'arán', 'arás', 'aríais', 'aría', 'aréis', 'aríamos', 'aremos', 'ará', 'aré', 'erían', 'erías', 'erán', 'erás', 'eríais', 'ería', 'eréis', 'eríamos', 'eremos', 'erá', 'eré', 'irían', 'irías', 'irán', 'irás', 'iríais', 'iría', 'iréis', 'iríamos', 'iremos', 'irá', 'iré', 'aba', 'ada', 'ida', 'ía', 'ara', 'iera', 'ad', 'ed', 'id', 'ase', 'iese', 'aste', 'iste', 'an', 'aban', 'ían', 'aran', 'ieran', 'asen', 'iesen', 'aron', 'ieron', 'ado', 'ido', 'ando', 'iendo', 'ió', 'ar', 'er', 'ir', 'as', 'abas', 'adas', 'idas', 'ías', 'aras', 'ieras', 'ases', 'ieses', 'ís', 'áis', 'abais', 'íais', 'arais', 'ierais', ' aseis', 'ieseis', 'asteis', 'isteis', 'ados', 'idos', 'amos', 'ábamos', 'íamos', 'imos', 'áramos', 'iéramos', 'iésemos', 'ásemos'))) != '') {
$word = substr($word, 0, -strlen($suf));
}
}
}
// Always do step 3.
$r1_txt = substr($word, $r1);
$r2_txt = substr($word, $r2);
$rv_txt = substr($word, $rv);
if (($suf = es_stemmer::endsinArr($rv_txt, array('os', 'a', 'o', 'á', 'í', 'ó'))) != '') {
$word = substr($word, 0, -strlen($suf));
} elseif (($suf = es_stemmer::endsinArr($rv_txt, array('e', 'é'))) != '') {
$word = substr($word, 0, -1);
$rv_txt = substr($word, $rv);
if (es_stemmer::endsin($rv_txt, 'u') && es_stemmer::endsin($word, 'gu')) {
$word = substr($word, 0, -1);
}
}
return es_stemmer::removeAccent($word);
}