Circular color schemes

[shoogle]

I would like to see support for circular data types. Circular data is ordered, but unlike sequential data the scale 'wraps around' so there is no true zero value, and no absolute notion of high or low (only relative comparisons can be made).

Examples of circular data:

• Angles (directions, rotations)
• Time periods (time of day, time of year, etc.)
• Musical pitch (C→D→E→F→G→A→B→C...)
• Color! (as perceived by humans) (R→O→Y→G→B→I→V→R...)

Thanks for the great tool BTW! :)