Table simplification is the process of converting a complex table into a simple table. A simple table is a table with every cell spanning exactly one row and one column.
Complex tables associate more than one row <th> header cell or more than one <th> column header cell to a data cell.
The process of table simplification involves splitting a complex table into multiple simple tables. <th> header cells, used for creating grouping relationships or levels within a table, are transferred to other HTML markup such as <h1>-<h6> headings.
General Technique
To divide a complex table into multiple simple tables, follow these steps:
Locate a complex table
See Example
H01
H02
H03
H04
H05
H06
H07
H08
H09
H10
H11
H12
D01
D02
D03
D04
D05
D06
D07
D08
D09
D10
H13
D11
D12
D13
D14
D15
D16
D17
D18
D19
For <td> data cells that span more than one row or column, split them to remove all row and column spanning. Duplicate the original cell's contents in all of its splitted cells.
See Example
Cells indicated with an asterisk (*) have changed from the previous step.
H01
H02
H03
H04
H05
H06
H07
H08
H09
H10
H11
H12
D01
D02 *
D02 *
D03
D04
D05 *
D06
D07
D08
D05 *
D09
D10 *
H13
D11
D12
D13
D10 *
D14
D15
D13 *
D16
D17 *
D17 *
D18
D19
Merge consecutive <th> header cells into a comma seperated list.
See Example
Cells indicated with an asterisk (*) have changed from the previous step.
H01, H02, H05, H06 *
H03, H07 *
H03, H08 *
H04, H09 *
H04, H10 *
H11, H12 *
D01
D02
D02
D03
D04
D05
D06
D07
D08
D05
D09
D10
H11, H13 *
D11
D12
D13
D10
D14
D15
D13
D16
D17
D17
D18
D19
Remove <th> header cell information from any cell whose entire row and column are also <th> header cells (often the top left most cell). Save the information in these affected cells for future steps.
See Example
Cells indicated with an asterisk (*) have changed from the previous step.
*
H03, H07
H03, H08
H04, H09
H04, H10
H11, H12
D01
D02
D02
D03
D04
D05
D06
D07
D08
D05
D09
D10
H11, H13
D11
D12
D13
D10
D14
D15
D13
D16
D17
D17
D18
D19
Split the table into multiple subtables. The most logical place to split a table is often along those borders that spans either the entire width or height of the table. If a subtable is still a complex table, split it again by repeating this step on that subtable.
See Example
H03, H07
H03, H08
H11,H12
D01
D02
D04
D05
D08
D05
H04, H09
H04, H10
D02
D03
D06
D07
D09
D10
H11,H13
D11
D12
D14
D15
D17
D17
D13
D10
D13
D16
D18
D19
Insert any missing <th> header cells into the subtables as a result of the table splitting.
See Example
Cells indicated with an asterisk (*) have changed from the previous step.
H03, H07
H03, H08
H11,H12
D01
D02
D04
D05
D08
D05
H04, H09
H04, H10
H11,H12 *
D02
D03
D06
D07
D09
D10
H03, H07 *
H03, H08 *
H11,H13
D11
D12
D14
D15
D17
D17
H04, H09 *
H04, H10 *
H11,H13 *
D13
D10
D13
D16
D18
D19
To reduce the number of subtables, join and group them by common headers using <h1>-<h6> headings. Re-use the header information in Step 4 to add additional description and context as needed.
