public function getMaxLength($csv_file = null)
	{
		$csv_file = $csv_file ? $csv_file : $this->csv_file;

		$sizes = array(0);
		if( ! $csv_file )
		{
			throw new NoDataException();
		}

		foreach($csv_file as $line)
		{
			$sizes[]=count($line->getElements() );
		}

		return max($sizes);
	}