Thanks for the feedback, the web UI does have a gallery link [0] with a few interactive examples [1]. I agree though, a screenshot like this would be a good addition to the homepage.
Yes, that's roughly accurate. Jan Pöschko (the creator of Mathics) went to Wolfram in 2012 and I went to Google at the end of 2016. Since then it's been largely unmaintained as I don't have the time to work on it unfortunately
The main issue was that generating the tables was extremely slow (~15mins). We solved this by packaging the tables, but when the version of ply changed a table regeneration was forced on our users.
The recursive descent parser was also simpler and significantly more performant.
The web interface does have inbuilt docs. Code introspection and tab completion are coming as part of the new interface (in progress) see https://github.com/mathics/IMathics
I'd say jupyter notebooks surpass Mathematica UX wise.
I maintain Mathics [1] which has it's own web interface e.g. [2]. I don't think the Mathics interface is as nice as MMA but the documentation bar on the side is really nice.
I'm working on a fully featured jupyter kernel that will eventually get merged into the main Mathics repo [1]. I was planning to inquire about some hosting in a couple of weeks (once my exams are over and I have a chance to finish the jupyter kernel off).
What's wrong with two column proofs? I think they're a great tool for getting into the absolutely rigorous mindset required for maths. Leslie Lamport even makes the case that professional mathematicians should use them to reduce publication errors [1].
My personal feeling (as a maths grad student) is that the utility of two column proofs depends on the field. For logic and algorithms sure but estimating integrals it becomes tedious quickly.
Mathics maintainer here.I'm glad you find Mathics fun to contribute to, I certainly do. Each function is a small independent part so it's really easy to get involved (that's a major goal of mine at least) Thanks for your contribution.
[0] https://pasteboard.co/IdIaJNo.png [1] https://pasteboard.co/IdIc7dc.png