Here
is some bloggy information about treemaps. Treemaps are cool when you want to visualize a weighted tree such as the tree of folders and files on your hard drive weighted according to their size. An excellent free utility to visualize your disk space occupation is Sequoia View.

Beyond Sequoia View, why such an interest from me for treemaps ? Well… Because I just realized I sort of reinvented and explored this concept several years ago without knowing the proper term. Treemaps… My experiments dealt with the use of treemaps for the visualization of graphs of information (networks composed with nodes and arcs).

For instance, let’s take the following graph composed with 8 nodes labelled from A to H.

When you « sit » on node A and try to look through the arcs to the rest of the graph, what can you see ? Answer : the treemap below. (each node is associated to a specific color)

What if you consider that the whole space (rectangle) of a given node should be separated in subrectangles for the associated nodes ? Then your treemap becomes somewhat fractal and you get this kind of visualization for the same 8 nodes graph seen from node A :

Or maybe you prefer the circle version of this treemap which may look more readable. Here it is with a limited depth (exploring no more than 3 arcs from the starting node) :

But it looks even nicer if you explore a high number of arcs :

I will soon post the programs that produce these treemaps and some more screenshots.