/**
* Static method extractTags
*
* @param string $content # input content
* @param int $top_k # top_k
* @param array $options # other options
*
* @return array $tags
*/
public static function extractTags($content, $top_k = 20, $options = array())
{
$defaults = array('mode' => 'default');
$options = array_merge($defaults, $options);
$tags = array();
$words = Jieba::cut($content);
$freq = array();
$total = 0.0;
foreach ($words as $w) {
$w = trim($w);
if (mb_strlen($w, 'UTF-8') < 2) {
continue;
}
if (isset($freq[$w])) {
$freq[$w] = $freq[$w] + 1.0;
} else {
$freq[$w] = 0.0 + 1.0;
}
$total = $total + 1.0;
}
foreach ($freq as $k => $v) {
$freq[$k] = $v / $total;
}
$tf_idf_list = array();
foreach ($freq as $k => $v) {
if (isset(self::$idf_freq[$k])) {
$idf_freq = self::$idf_freq[$k];
} else {
$idf_freq = self::$max_idf;
}
$tf_idf_list[$k] = $v * $idf_freq;
}
arsort($tf_idf_list);
$tags = array_slice($tf_idf_list, 0, $top_k, true);
return $tags;
}
/**
* Static method __cutDAG
*
* @param string $sentence # input sentence
* @param array $options # other options
*
* @return array $words
*/
public static function __cutDAG($sentence, $options = array())
{
$defaults = array('mode' => 'default');
$options = array_merge($defaults, $options);
$words = array();
$N = mb_strlen($sentence, 'UTF-8');
$DAG = Jieba::getDAG($sentence);
Jieba::calc($sentence, $DAG);
$x = 0;
$buf = '';
while ($x < $N) {
$current_route_keys = array_keys(Jieba::$route[$x]);
$y = $current_route_keys[0] + 1;
$l_word = mb_substr($sentence, $x, $y - $x, 'UTF-8');
if ($y - $x == 1) {
$buf = $buf . $l_word;
} else {
if (mb_strlen($buf, 'UTF-8') > 0) {
if (mb_strlen($buf, 'UTF-8') == 1) {
if (isset(self::$word_tag[$buf])) {
$buf_tag = self::$word_tag[$buf];
} else {
$buf_tag = "x";
}
array_push($words, array("word" => $buf, "tag" => $buf_tag));
$buf = '';
} else {
$regognized = self::__cutDetail($buf);
foreach ($regognized as $key => $word) {
array_push($words, $word);
}
$buf = '';
}
}
if (isset(self::$word_tag[$l_word])) {
$buf_tag = self::$word_tag[$l_word];
} else {
$buf_tag = "x";
}
array_push($words, array("word" => $l_word, "tag" => $buf_tag));
}
$x = $y;
}
if (mb_strlen($buf, 'UTF-8') > 0) {
if (mb_strlen($buf, 'UTF-8') == 1) {
if (isset(self::$word_tag[$buf])) {
$buf_tag = self::$word_tag[$buf];
} else {
$buf_tag = "x";
}
array_push($words, array("word" => $buf, "tag" => $buf_tag));
} else {
$regognized = self::__cutDetail($buf);
foreach ($regognized as $key => $word) {
array_push($words, $word);
}
}
}
return $words;
}
