Php-filter Common Words Or Stop Words

[jd_19]

$CommonWords=array("a"=>1,"as"=>1,"any"=>1,"all"=>1,"am"=>1,"an"=>1,"and"=>1,"are"=>1,"at"=>1,
"b"=>1,"be"=>1,"but"=>1,"by"=>1,
"c"=>1,"can"=>1,
"d"=>1,"did"=>1,"does"=>1,"do"=>1,
"e"=>1,"each"=>1,"else"=>1,"even"=>1,"ever"=>1,
"f"=>1,"for"=>1,"from"=>1,
"g"=>1,"go"=>1,"get"=>1,....................AND SO ON

AND THEN

$search_keywords=strtolower(trim($keywords));
$arrWords = explode(" ", $search_keywords);

    //remove duplicates
    $arrWords=array_unique($arrWords);

    $searchWords=array();
    $junkWords=array();
    foreach($arrWords as $word)
        //remove common words
        if(!$CommonWords[$word]){
            $searchWords[]=$word;
        }else{
            $junkWords[]=$word;
        }

---

CAN ANY ONE PLEASE EXPLAIN THE LOGIC USED BEHIND THE ARRAY OF COMMON WORDS AS SHOWN ABOVE.........

[Installer]

I'LL GIVE IT A SH...Sorry, I mean I'll give it a shot (code formatted and posted so as to be readable):

// Create array of words to, pesumably, ignore, used as the array indexes
// (why not just an array of the words as values, I don't know):
$CommonWords = array("a" => 1, "as" => 1, "any" => 1, "all" => 1 , "am" => 1, "an" => 1, "and" => 1, "are" => 1, "at" => 1,
"b" => 1, "be" => 1, "but" => 1, "by" => 1,
"c" => 1, "can" => 1,
"d" => 1, "did" => 1, "does" => 1, "do" => 1,
"e" => 1, "each" => 1, "else" => 1, "even" => 1, "ever" => 1,
"f" => 1, "for" => 1, "from" => 1,
"g" => 1, "go" => 1, "get" => 1);

// This removes whitespace from the ends of the keyword phrase,
// and coverts it to lowercase to make word-matching easier:
$search_keywords = strtolower(trim($keywords));
// This makes an array of the separate words in the keyword phrase:
$arrWords = explode(" ", $search_keywords);

//remove duplicates
// This removes duplicate words from the keyword array:
$arrWords = array_unique($arrWords);

// Initialize arrays, not really needed:
$searchWords = array();
$junkWords = array();
// Iterate through the keyword array:
foreach ($arrWords as $word) {
    //remove common words
    // Notice level error generated if $word not in common word array;
    // also if two consecutive spaces entered in keyword phrase,
    // "" will be added to the search word array (not desired, I assume):
    if(!$CommonWords[$word]){
        // If the word is not in the common words array, i.e. if the key $word doesn't exist,
        // keep it to use in the search:
        $searchWords[] = $word;
    } else {
        // If it is in the common words array, store it (why?) as junk:
        $junkWords[] = $word;
    }
}

Here's a better (imo) and more sensible (imo), though not thoroughly robust, way to do it:

$CommonWords = array('a', 'as', 'any', 'all', 'am', 'an', 'and', 'are', 'at',
                     'b', 'be', 'but', 'by',
                     'c', 'can',
                     'd', 'did', 'does', 'do',
                     'e', 'each', 'else', 'even', 'ever',
                     'f', 'for', 'from',
                     'g', 'go', 'get');

$search_keywords = strtolower(trim($keywords));
$arrWords = explode(' ', $search_keywords);
$arrWords = array_unique($arrWords);

foreach ($arrWords as $word) {
    if (!in_array($word, $CommonWords) && (trim($word) != '')) {
        $searchWords[] = $word;
    } else {
        $junkWords[] = $word;
    }
}