Comment by tantalor

1 month ago

Pick a digit, repeat, don't stop.

Exactly right. You can pick and use real numbers, as long as they are only queried to finite precision. There are lots of super cool algorithms for doing this!

  • That's just saying that you can pick and use rational numbers (which are a subset of the reals.)

    • Kind of, but you're not just picking rationals, you're picking rationals that are known to converge to a real number with some continuous property.

      You might be interested in this paper [1] which builds on top of this approach to simulate arbitrarily precise samples from the continuous normal distribution.

      [1] https://dl.acm.org/doi/10.1145/2710016

    • Not really. You can simulate a probability of 1/x by expanding 1/x in binary and flipping a coin repeatedly, once for each digit, until the coin matches the digit (assign heads and tails to 0 and 1 consistently). If the match happened on 1, then it's a positive result, otherwise negative. This only requires arbitrary but finite precision but the probability is exactly equal to 1/x which isn't rational.

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