Test 2

Everything's just been hunky-dorey.


...

I guess that wouldn't be an acceptably meaty Slog post, would it? Really though, I've just been sailing through. I love the material, I love the assignments and the problem sets, I have nothing to complain about.

I just came back from term test 2, so I suppose I'll talk about that briefly, for lack of anything better to pontificate on. It went pretty well, except for the last question, which was about proving the termination of a loop. I think my logic was correct, but I leapt into the proof without looking first, and so I know the approach I took was inelegant (and probably had some gaps). For some reason, I decided to make a function that takes valid loop indices as its domain, and spits out the value of n at that index. Then I proved that it was decreasing, and always natural. I only mentioned loop invariants in passing, which was kind of silly.

It's a mistake that I've made a lot in tests, of getting antsy about the time limit, and feeling obliged to start writing stuff down as soon as I see the question, not wanting to "waste time" planning out a proof. For that reason, I often end up writing out base cases that turn out to be redundant, or make some claims without the appropriate intermediate steps, and turn my paper into a roadmap of arrows, inserting lines in the cracks where they're needed. So I suppose something to work on in the future would be remembering to take time to make a quick mental plan of where I want the proof to go, rather than blindly filling in a predicate and some base cases, and hoping that they'll lead me to inferences, that will lead me to inferences, that will lead me to the conclusion I want.