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What field do you work in, and how many digits of pi do you use? (self.asklemmy)

submitted 8 months ago by nycki to c/[email protected]

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This article says that NASA uses 15 digits after the decimal point, which I'm counting as 16 in total, since that's how we count significant digits in scientific notation. If you round pi to 3, that's one significant digit, and if you round it to 1, that's zero digits.

I know that 22/7 is an extremely good approximation for pi, since it's written with 3 digits, but is accurate to almost 4 digits. Another good one is √10, which is accurate to a little over 2 digits.

I've heard that 'field engineers' used to use these approximations to save time when doing math by hand. But what field, exactly? Can anyone give examples of fields that use fewer than 16 digits? In the spirit of something like xkcd: Purity, could you rank different sciences by how many digits of pi they require?

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[–] [email protected] 5 points 8 months ago (1 children)

I don't use Pi but I do use GPS fairly often and try to get down to 7 digits after the decimal point. Our equipment probably isn't quite that accurate though lol so the seventh digit is likely a guess. Probably even the 6th digit.

[–] [email protected] 6 points 8 months ago

Well I’m an uber driver and I’m requesting you start using 9 or 10 digits because my passengers are all over the place when I’m supposed to be able to see where they are.