[docs] add design patterns tutorial

[odow]

Motivated by this discussion on Discourse: https://discourse.julialang.org/t/integrating-mathoptinterface-into-an-industry-scale-project-e-g-constraint-management/71943

I think this should be pretty helpful for people wanting to create larger JuMP models. It was definitely a gap in our documentation.

Preview link: https://jump.dev/JuMP.jl/previews/PR2812/tutorials/getting_started/design_patterns_for_larger_models/

Part of #2348

[codecov]

Codecov Report

Merging #2812 (cd3e929) into master (fea6787) will not change coverage.
The diff coverage is n/a.

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[jd-foster]

This is great overall. I think it takes the documentation offering to the next level.

[odow]

Yeah I'm massively in favor of more involved tutorials like this. I think we can slim-down the number of existing ones in favor of fewer, more in-depth tutorials.

[pboes]

Overall this is really fantastic, I'm very glad I asked this innocuous question and am completely blown away by the fact that within two days this should have generated a tutorial on the docs that I personally have already found super helpful. So thanks @odow, @jd-foster, @rschwarz.

One additional section that I would probably try to add is how to use variable and constraint names (in terms of the base_name/String representation) to generate useful printouts of models. I guess those names aren't used a lot in practice and helping get a quick overview of which constraints are in action in a given model would seem like a place for them to shine. I'm happy to try and provide an example of what I have in mind when I have more time over the weekend. But since there is an example of custom printing for the data already, seeing how a model could be printed informatively would seem to be on-topic as well...

[dourouc05]

That's a great addition to the docs! It's not the only way to implement large-scale models, but it's a very good way to do it.

I think we can slim-down the number of existing ones in favor of fewer, more in-depth tutorials.

I wouldn't go into that direction, at least from the point of view of a user: I prefer to have specific tutorials instead of large ones that present many topics that are not necessarily that related and could be dealt with separately.

[odow]

I'm very glad I asked this innocuous question and am completely blown away by the fact that within two days this should have generated a tutorial on the docs that I personally have already found super helpful

Great! I've known that this has been a stumbling block for a while, so you finally motivated me to write it.

If you have other suggestions or questions, please fire away. We're very receptive of constructive criticism.

to generate useful printouts of models

This is covered in various parts:

• https://jump.dev/JuMP.jl/dev/manual/variables/#Variable-names
• https://jump.dev/JuMP.jl/dev/manual/constraints/#Constraint-names
• https://jump.dev/JuMP.jl/dev/manual/models/#Print-the-model

For larger models, however, printing is almost uniformly a bad idea because the printouts become huge. (For various reasons, we don't print the concise algebraic form of the model.)

You could potentially do something with the Names registered in the model: part of the print-out, which you can programmatically access with keys(object_dictionary(model)). I'm not sure there is a good way to provide general advice though. It's probably up to you to perform some book-keeping in an external data-structure about what constraints have been added to the model, rather than querying the JuMP model directly.

[odow]

Just re-firing the CI. Looks like it got caught in the recent outage of GitHub.

[odow]

Thanks for the feedback.