add 'amplitude' option for cmap_encoding in plot module

[ahms5]

We could add 'amplitude' as an additional option for cmap_encoding in the plot module, see e.g. here).
the method in the background _balloon_color_data also allows amplitude.

Is there a specific reason, why this is not supported anymore?

[mberz]

This is not supported, since negative radii do not make sense ;)

[ahms5]

it is not about radii, it is about the data, radii also dont have a meaningful phase.
it could also be real time data, where amplitude would make sence

[mberz]

Ah, I see what you mean. Sorry for the misunderstanding.
I guess it's most useful for pcolor_sphere.
For the balloon plots the representation seems a bit counterintuitive, but I don't mind if that's something people need.

[ahms5]

I think it can also be added later in 1.1.0, it will not change API, just introduce a new feature.

[mberz]

I'll remove the milestone until a decision is made on this.