# how do you find the n'th digit in a quotient of division

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### #1paul0n0n

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Posted 31 August 2009 - 03:13 AM

How do you do it?
Here is an example of what I mean.
q = "0.2893798172383982716"
other then doing long division how do you find, say, 7 in q. Or rather is there a formula for finding, if n = 5 the outcome would then be 3 in q. or if n = 13 the outcome would be 8.

why would i want to do this? just cause, i guess, asking and looking at things.

### #2Reedbeta

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Posted 31 August 2009 - 05:41 AM

Well, you know how to do long division, don't you? Just start dividing and keep going until you get to the desired digit.
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Posted 31 August 2009 - 07:20 PM

Depends on how far in you want to go. Reedbeta's idea is KISS for low n's. But, if you want mathematical formula (cuz it's getz the chicks, right? Right!?!) a fancy way to get it is that the nth digit of a/b is the 1st digit of (10^(n-1)a mod /b, a.k.a. floor(10 * (10^(n-1)a mod / mod 10.
Hyperbole is, like, the absolute best, most wonderful thing ever! However, you'd be an idiot to not think dogmatism is always bad.

### #4paul0n0n

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Posted 01 September 2009 - 02:32 AM

That is what I was looking for. And yes it gets chicks!

### #5poita

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Posted 07 September 2009 - 11:20 AM

Convert to a string and then just index it :)

I can't imagine any situation where this would actually be a performance bottleneck.

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