Z-plane pole and zero plots

[endolith]

Referencing matplotlib/matplotlib#22867 (comment)

I have two versions published (not sure which is better) https://gist.github.com/endolith/4625838 https://gist.github.com/endolith/8f202597a663220a6f10#file-pairing-py and just pushed my latest (messy) version here:

https://gist.githubusercontent.com/endolith/98acf9824dbf10a01795/raw/3dd5e41d3c1f98f68cd9ae0e1d9d55856f96ea20/pzplot.py

and function for making plots like this:

is here:

https://gist.githubusercontent.com/endolith/98acf9824dbf10a01795/raw/3dd5e41d3c1f98f68cd9ae0e1d9d55856f96ea20/helpful_plots.py

If you use it, please hide all my crap commit messages and comments :D I can work on it, too, but no time right now.

Superscripts for multiple poles don't seem to be working anymore, I don't know why.

[oscargus]

Sorry for the late reply. Thanks for this! I've seen this code when looking for solutions, but thought I'd write something from scratch to not get into licensing issues. This is my attempt https://github.com/oscargus/mplsignal/blob/main/mplsignal/plane_plots.py although I should really provide some examples... (I have multiple poles/zero subscripts with, at least conceptually, configurable distance, although I can realize some issues in the clustering approach already. Also, my approach was that the user should be able to provide an axis object to make it a bit more general.)

Once I get back to this and am happy with my approach, I will take another look into your and see if there is anything missing etc. I think I got stuck at trying to inherit the Matplotlib color cycler last time. But looking forward to get a bit of free time to actually get it into good enough shape to provide a first release.

(There are also deprecations of the mlab module in Matplotlib likely happening, so this would be a good place to inherit those functions.)