$query = $this->db->query("SELECT * FROM Persoonlijkheid WHERE UserID = ?", array($id));
            return $query->result_array();

function pdistance($value1, $value2){
    $sum = 0;
    for($i = 0; $i < 4; $i++){
        $max = max($value1[$i], $value2[$i]);
        $min = min($value1[$i], $value2[$i]);
        $sum += ($max - $min);
    }
    $afstand = $sum/400;
    return $afstand;
 }