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xkcd #217: e to the pi Minus pi (31 Jan 2007)
(programming.dev)
cross-posted from: https://programming.dev/post/8653164
Transcript:
Cueball: Hey, check it out: e^π^−π is 19.999099979. That's weird.
Black Hat: Yeah. That's how I got kicked out of the ACM in college.
Cueball: ...what?Black Hat: During a competition, I told the programmers on our team that e^π^−π was a standard test of floating-point handlers -- it would come out to 20 unless they had rounding errors.
Cueball: That's awful.
Black Hat: Yeah, they dug through half their algorithms looking for the bug before they figured it out.
Hover text:
Also, I hear the 4th root of (9^2^ + 19^2^/22) is pi.
That's sort of part of the joke. ACM is the "Association for Computing Machinery" one of the biggest and oldest and nerdiest computer clubs.
ACM hosts all kinds of SIGs (special interest groups) - clubs dedicated to interest in (sometimes deeply esoteric) aspects of computer science. For a few of them, hand-coding a new specialized fast floating point calculation code during a contest could easily come up.
And ACM has a code of ethics, so it is technically possible to get kicked out.
So there's technically a situation where lying to a peer, on purpose, in a particularly mean context (such as a competition) about a floating point number computation - could actually get someone kicked out of ACM.
Edit: Additonal context that helps the joke - my experiences with ACM have all been super chill , relaxed and friendly. So "I got kicked out of ACM" is also a "you did what?!" setup for the joke.
Thanks for the context on ACM saving me a search. I would like to add that I wouldn’t characterize it as ‘mean’ but moreso trolling them for being unaware of Gelfond’s Constant.