Polar chart sectors starting from positive radius

[sudoLife]

Right now, you can radius to start from a positive value.

However, it is wrong to still draw it like a full sector after that (wrong angles, wrong radius). The bottom part should be cut out.

Here's how it should look (pardon my drawing skills):

Such plot is very useful in engineering applications. Would it be possible to implement it?

[gvwilson]

Hi - we are trying to tidy up the stale issues and PRs in Plotly's public repositories so that we can focus on things that are still important to our community. Since this one has been sitting for several years, I'm going to close it; if it is still a concern, please add a comment letting us know what recent version of our software you've checked it with so that I can reopen it and add it to our backlog. Thanks for your help - @gvwilson