By default, the rectangles in a treemap appear in alphabetical order. Values progress from the top left to the lower right. To change this ordering, specify an Ordering variable. When an Ordering variable is specified, the rectangles appear with the values progressing from the bottom left to the upper right.
Note: If you use the Squarify option, the rectangles are ordered by size and the Ordering variable is ignored. To see an example using Squarify, see Example of Squarifying Data.
If you specify a single Ordering variable, the rectangles are clustered, with the high levels or large values together, and the low levels or small values together.
If you specify two Ordering variables, the treemap arranges the rectangles horizontally by the first ordering variable, and vertically by the second ordering variable. This approach can be useful for geographic data.
For example, suppose the Cities.jmp data is ordered by US state. If you order the data by latitude and or longitude, the Treemap rectangles are drawn ordered by the location of the US state.