public function array_fields($array, array $fields){
        $newArray= array();
        foreach ($array as $value) {
            $newValue= array();
            foreach ($fields as $key) {
                if(array_key_exists($key, $value)){
                    $newValue[$key]= $value[$key];
                }
            }
            $newArray[]= $newValue;
        }        
        return $newArray;
    }