this post was submitted on 19 Jan 2024
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xkcd

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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.

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[–] kbal@fedia.io 11 points 7 months ago

It seems plausible enough to me. Many comp sci undergrads would be dimly aware that floating point arithmetic is notoriously difficult to get right and can often lead to surprising errors if you get it slightly wrong, and also dumb enough to believe that e^π^−π is exactly 20.