public function format($format)
    {
        if(Format::exist($format))
            $this->format = Format::get($format);
        else
            Format::invalidType();

        return $this;
    }
public function format($format)
    {
        if(Format::exist($format))
            $this->format = Format::get($format);
        else
            Format::invalidType();

        return $this;
    }
public function format ( $ format ) { if ( Format :: exist ( $ format ) ) $ this -> format = Format :: get ( $ format ) ; else Format :: invalidType ( ) ; return $ this ; }
Set the format for the report.
@param $format
@return $this
Set the format for the report .