public function getCell($row_num, $col_num, $val_only = true)
{
// check whether the cell exists
if (!$this->isCellExists($row_num, $col_num)) {
throw new \Exception('Cell ' . $row_num . ',' . $col_num . ' doesn\'t exist', SimpleExcelException::CELL_NOT_FOUND);
}
return $this->table_arr[$row_num - 1][$col_num - 1];
}