# File lib/spreadsheet/excel/writer/worksheet.rb, line 381
  def write_dimensions
    # Offset  Size  Contents
    #      0     4  Index to first used row
    #      4     4  Index to last used row, increased by 1
    #      8     2  Index to first used column
    #     10     2  Index to last used column, increased by 1
    #     12     2  Not used
    write_op 0x0200, @worksheet.dimensions.pack(binfmt(:dimensions))
  end