function stem($word)
{
//$word = lower_case($word);
// � and � should be treated as a vowel followed by a consonant
$word = str_replace('�', 'a~', $word);
$word = str_replace('�', '~o', $word);
$len = strlen($word);
if ($len <= 2) {
return $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; $i++) {
if (pt_stemmer::is_vowel($word[$i]) && !pt_stemmer::is_vowel($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; $i++) {
if (pt_stemmer::is_vowel($word[$i]) && !pt_stemmer::is_vowel($word[$i + 1])) {
$r2 = $i + 2;
}
}
if ($len > 3) {
if (!pt_stemmer::is_vowel($word[1])) {
// If the second letter is a consonant, RV is the region after the next following vowel
$rv = pt_stemmer::getNextVowelPos($word, 2) + 1;
} elseif (pt_stemmer::is_vowel($word[0]) && pt_stemmer::is_vowel($word[1])) {
// or if the first two letters are vowels, RV is the region after the next consonant
$rv = pt_stemmer::getNextConsonantPos($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 = $word;
// Step 1: Standard ending removal
if (($suf = pt_stemmer::endsinArr($r2_txt, array('amentos', 'imentos', 'amento', 'imento', 'adoras', 'adores', 'a�o~es', 'ismos', 'istas', 'adora', 'a�a~o', 'antes', '�ncia', 'ezas', 'icos', 'icas', 'ismo', '�vel', '�vel', 'ista', 'osos', 'osas', 'ador', 'ante', 'eza', 'ico', 'ica', 'oso', 'osa'))) != '') {
$word = substr($word, 0, -strlen($suf));
# rule1
} elseif (($suf = pt_stemmer::endsinArr($r2_txt, array('log�a', 'log�as'))) != '') {
$word = substr($word, 0, -strlen($suf)) . 'log';
} elseif (($suf = pt_stemmer::endsinArr($r2_txt, array('uci�n', 'uciones'))) != '') {
$word = substr($word, 0, -strlen($suf)) . 'u';
} elseif (($suf = pt_stemmer::endsinArr($r2_txt, array('�ncia', '�ncias'))) != '') {
$word = substr($word, 0, -strlen($suf)) . 'ente';
} elseif (($suf = pt_stemmer::endsinArr($r2_txt, array('ativamente', 'ivamente', 'osamente', 'icamente', 'adamente'))) != '') {
$word = substr($word, 0, -strlen($suf));
} elseif (($suf = pt_stemmer::endsinArr($r1_txt, array('amente'))) != '') {
$word = substr($word, 0, -strlen($suf));
} elseif (($suf = pt_stemmer::endsinArr($r2_txt, array('antemente', 'avelmente', '�velmente', 'mente'))) != '') {
$word = substr($word, 0, -strlen($suf));
} elseif (($suf = pt_stemmer::endsinArr($r2_txt, array('abilidade', 'abilidades', 'icidade', 'icidades', 'ividad', 'ividades', 'idade', 'idades'))) != '') {
$word = substr($word, 0, -strlen($suf));
} elseif (($suf = pt_stemmer::endsinArr($r2_txt, array('ativa', 'ativo', 'ativas', 'ativos', 'iva', 'ivo', 'ivas', 'ivos'))) != '') {
$word = substr($word, 0, -strlen($suf));
} elseif (($suf = pt_stemmer::endsinArr($rv_txt, array('eira', 'eiras'))) != '') {
$word = substr($word, 0, -strlen($suf)) . 'ir';
}
if ($word != $word_after0) {
$r1_txt = substr($word, $r1);
$r2_txt = substr($word, $r2);
$rv_txt = substr($word, $rv);
}
$stem = $word;
if ($stem == $word_orig) {
// Do step 2 if no ending was removed by step 1: now remove verb suffixes
if ($suf = pt_stemmer::endsinArr($rv_txt, array('ar�amos', 'er�amos', 'ir�amos', '�ssemos', '�ssemos', '�ssemos', 'ar�eis', 'er�eis', 'ir�eis', '�sseis', '�sseis', '�sseis', '�ramos', '�ramos', '�ramos', '�vamos', 'aremos', 'eremos', 'iremos', 'ariam', 'eriam', 'iriam', 'assem', 'essem', 'issem', 'ara~o', 'era~o', 'ira~o', 'arias', 'erias', 'irias', 'ardes', 'erdes', 'irdes', 'asses', 'esses', 'isses', 'astes', 'estes', 'istes', '�reis', 'areis', '�reis', 'ereis', '�reis', 'ireis', '�veis', '�amos', 'armos', 'ermos', 'irmos', 'aria', 'eria', 'iria', 'asse', 'esse', 'isse', 'aste', 'este', 'iste', 'arei', 'erei', 'irei', 'aram', 'eram', 'iram', 'avam', 'arem', 'erem', 'irem', 'ando', 'endo', 'indo', 'adas', 'idas', 'ar�s', 'aras', 'er�s', 'eras', 'ir�s', 'avas', 'ares', 'eres', 'ires', '�eis', 'ados', 'idos', '�mos', 'amos', 'emos', 'imos', 'iras', 'ada', 'ida', 'ar�', 'ara', 'er�', 'era', 'ir�', 'ava', 'iam', 'ado', 'ido', 'ias', 'ais', 'eis', 'ira', 'ia', 'ei', 'am', 'em', 'ar', 'er', 'ir', 'as', 'es', 'is', 'eu', 'iu', 'ou'))) {
$word = substr($word, 0, -strlen($suf));
}
if ($word != $word_after1) {
$r1_txt = substr($word, $r1);
$r2_txt = substr($word, $r2);
$rv_txt = substr($word, $rv);
}
$stem = $word;
}
if ($stem != $word_orig) {
// Step 3
if (pt_stemmer::endsin($rv_txt, 'ci')) {
$word = substr($word, 0, -1);
$r1_txt = substr($word, $r1);
$r2_txt = substr($word, $r2);
$rv_txt = substr($word, $rv);
}
} else {
// Step 4 conditioned
if (($suf = pt_stemmer::endsinArr($rv_txt, array('os', 'a', 'i', 'o', '�', '�', '�'))) != '') {
$word = substr($word, 0, -strlen($suf));
$r1_txt = substr($word, $r1);
$r2_txt = substr($word, $r2);
$rv_txt = substr($word, $rv);
}
}
// Always perform step 5
if (($suf = pt_stemmer::endsinArr($rv_txt, array(' cie', ' ci�', ' ci�', 'gue', 'gu�', 'gu�', 'e', '�', '�'))) != '') {
$word = substr($word, 0, -strlen($suf));
}
$word = str_replace('a~', '�', $word);
$word = str_replace('~o', '�', $word);
return pt_stemmer::removeAccent($word);
}
