Statistical Graphics and more

Color brushing (i.e., the persistent assignment of colors to cases) was one of the most requested and most ignored (on my side) features for Mondrian. I gave in at some point and ever since I get the never ending complaint over using “the wrong” colors – which I now ignore for the most part as n users will have n different preferred color schemes.

Nonetheless, there is the continuous color scale which usually utilizes some sort of rainbow color scheme in order to differentiate between a maximum of hues. The whole thing seem to be pretty easy to implement in HSB color space. Once you decided on some reasonable S and B you only need to go round in the H circle and you are done. Here is what you get:

Looks pretty neat, but has two obvious problems:

• If you use the complete circle, you won’t be able to distinguish between the values at the edges, as they are actually the same
• If you use a background color (light yellow for Mondrian) you should avoid this color altogether.

The possible solution solves both problems at once. The first problem needs to avoid a certain color range such that “minimum color” and “maximum color” are far enough apart. For Mondrian, this is certainly the yellow range; which solves the second problem. This is what the update looks like:

No spectacular change, but this is actually the solution which I should have thought of in the first place.