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by infogulch 782 days ago
Are you sure? Maybe this isn't a good test but it seems pretty evenly distributed to me:

https://go.dev/play/p/IeJQEAclBCU

Edit: maybe this shows the bias better: https://go.dev/play/p/3eKJibIlF1a
1 comments
cmeacham98 782 days ago
UInt32Max (i.e. 4294967295) is divisible by 3, so your code actually is perfectly random (or more accurately, as random as go's rand package). It would be biased with N=4, for example.

Regardless, with small values of N, the bias is very slight so you would need many many iterations to see the imperfection in a statically significant way.

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infogulch 782 days ago
That makes sense.

A quick search didn't reveal any good resources for how to test the quality of a random number generator in a number range. Is what I came up with the best strategy, and you just need to run it for much longer (and compare to a known-good implementation) to see the difference?

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codeflo 782 days ago
Why would you need to “see” it? Unlike the distribution of the RNG itself, this is trivial to solve analytically.
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