Скрипт для определения повторяющихся фраз/слов (публикация статей)

/* ==================================================== ##
## SEOKEYWORDS FUNCTION | CLASS API ##
## ==================================================== */
function seokeywords($contents,$symbol=5,$words=35){
$contents = @preg_replace(array("'<[\/\!]*?[^<>]*?>'si","'([\r\n])[\s]+'si","'&[a-z0-9]{1,6};'si","'( +)'si"),
array("","\\1 "," "," "),strip_tags($contents));

$rearray = array("~","!","@","#","$","%","^","&","*","(",")","_","+",
"`",'"',"№",";",":","?","-","=","|","\"","\\","/",
"[","]","{","}","'",",",".","<",">","\r\n","\n","\t");

$adjectivearray = array("ые","ое","ие","ий","ая","ый","ой","ми");


$contents = @str_replace($rearray," ",$contents);
$this->keywordcache = @explode(" ",$contents);
$rearray = array();

foreach($this->keywordcache as $word){
if(strlen($word)>=$symbol && !is_numeric($word)){
$adjective = substr($word,-2);
if(!in_array($adjective,$adjectivearray)){
$rearray[$word] = (array_key_exists($word,$rearray)) ? ($rearray[$word] + 1) : 1;
}
}
}

@arsort($rearray);
$this->keywordcache = @array_slice($rearray,0,$words);
$keywords = "";

foreach($this->keywordcache as $word=>$count){
$keywords.= ",".$word;
}

return substr($keywords,1);
}