Minor changes in response to 2026-02-25 course run

[JostMigenda]

Resolves several points mentioned in #40. In particular:

Added examples of agent-based models in various disciplines, to illustrate relevance of predprey model.

• In the pandas/vectorisation exercise:
  • We could emphasize more strongly how the solution is basically just taking the existing pythagoras function and replacing df['f_vertical'] with vertical. Maybe switch from np.sqrt() to **0.5 to make this even more explicit?

Done; and explained why np.sqrt() is preferable.

• Talking about “the vertical column” and “the horizontal column” is slightly awkward. 😅 Time to bikeshed column names? (My first thought was latitude/longitude, but that implies a spherical geometry, so Pythagoras is no longer valid; maybe length/width would work?)

Done.

• Doing a live demo of the parallelised downloads example is scary; I’ve had a brief network glitch the first time I tried it, so I got a bunch of error messages. It worked a few seconds later when I tried a second time; but oof … That probably deserves an instructor note.

Improved exception handling so network glitches don’t lead to printing a full stack trace any more. Should now cause much less of an adrenaline spike if the demo fails; so I think this is okay.

[github-actions]

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⏱️ Updated at 2026-03-17 12:58:13 +0000

[Robadob]

I'm happy with this in principle.

Do let me know if you would like me to write a longer summary of the model (and ABM), it wouldn't be too difficult to draft, though it will probably end up being several hundred words.

[JostMigenda]

I think several hundred words of explanation in the main text would be too much. But a slightly longer summary of the model, to help people looking at the code get an overview over the structure, could be good as a module-level docstring in predprey.py itself.

That’s independent of this PR, though; so I’ll merge this one now. Thanks for the review!

[Robadob]

I think several hundred words of explanation in the main text would be too much. But a slightly longer summary of the model, to help people looking at the code get an overview over the structure, could be good as a module-level docstring in predprey.py itself.

That’s independent of this PR, though; so I’ll merge this one now. Thanks for the review!

Thanks, I'll add it to my private todo list and hopefully find time before next week.