Remaining work on this pull request:

• fix build failure, see https://github.com/alex-hhh/plot/runs/832915416
• document the new functions (arrows and arrows3d) plus the parameters in the plot manual
• not sure if using scaling for the arrow size and angle is the best way (my preference would be to specify the size directly, but I need to try things out first).
• add the plot parameters to one of the parameter groups, otherwise the plot snips will not use these parameters, see
• add an example/test case of using these parameters, for an example see https://github.com/racket/plot/blob/master/plot-test/plot/tests/PRs/46.rkt

Given that this is an old pull request, I will work on these tasks, as time allows.

Hi @pbpf , I understand this is an old pull request and I am happy to complete the work to merge it in, but before I do that, can you please explain what types of data needs to be plotted using arrows? The vector-field renderer can already be used for vector fields, where the arrows make most sense, but I cannot think of any other use case.

I don't know the original use case for this pull request, but at some point I did something similar to make plots for a course in mechanics:
https://bdeket.synology.me/mechanica/0702circlevector.gif
I could help with this, but what would be the right way to work on someone else's PR?

Thanks for providing an example and for wanting to work on this. The simplest way is to start a new branch in your repository, merge this branch into yours and continue the work, creating a new pull request. Last I checked, the build was failing for this branch (the pull request was created before automated builds were set up). Let me know if you need help with anything.

This is now done as part of #67, closing this pull request.