GNU Octave
GNU Octave is a free program, shown here through the code for its project website, which explains how the website is built and updated. The material does not describe Octave's calculating features, so its use for math and science is not confirmed here.
How hard it is to start using it. Easy: install it like a normal app, or use it in your browser. Advanced: you run it on your own server, use the command line, or it is a tool for developers.
Listed in
Math and science use not described in the material given
How to help
AI contributionsNot stated
The project has not said how it feels about AI-written contributions. Maintainers can set this by claiming the listing.