def write_blank(*args)
      # Check for a cell reference in A1 notation and substitute row and column
      row, col, xf = row_col_notation(args)
      raise WriteXLSXInsufficientArgumentError if [row, col].include?(nil)

      # Don't write a blank cell unless it has a format
      return unless xf

      # Check that row and col are valid and store max and min values
      check_dimensions(row, col)
      store_row_col_max_min_values(row, col)

      store_data_to_table(BlankCellData.new(self, row, col, xf))
    end
def write_blank(*args)
      # Check for a cell reference in A1 notation and substitute row and column
      row, col, xf = row_col_notation(args)
      raise WriteXLSXInsufficientArgumentError if [row, col].include?(nil)

      # Don't write a blank cell unless it has a format
      return unless xf

      # Check that row and col are valid and store max and min values
      check_dimensions(row, col)
      store_row_col_max_min_values(row, col)

      store_data_to_table(BlankCellData.new(self, row, col, xf))
    end
:call-seq:
   write_blank(row, col, format)

 Write a blank cell to the specified row and column (zero indexed).
 A blank cell is used to specify formatting without adding a string
 or a number.

     worksheet.write_blank(0, 0, format)

 This method is used to add formatting to cell which doesn't contain a
 string or number value.

 A blank cell without a format serves no purpose. Therefore, we don't write
 a BLANK record unless a format is specified. This is mainly an optimisation
 for the write_row() and write_col() methods.

 Excel differentiates between an "Empty" cell and a "Blank" cell.
 An "Empty" cell is a cell which doesn't contain data whilst a "Blank"
 cell is a cell which doesn't contain data but does contain formatting.
 Excel stores "Blank" cells but ignores "Empty" cells.

 As such, if you write an empty cell without formatting it is ignored:

     worksheet.write('A1', nil, format )    # write_blank()
     worksheet.write('A2', nil )            # Ignored

 This seemingly uninteresting fact means that you can write arrays of
 data without special treatment for +nil+ or empty string values.

 See the note about {"Cell notation"}[#label-Cell+notation].