3 ms·

More interesting question: how do you keep a running standard deviation?

• fgimenez 18y ago
  Here's Knuth's way to keep a running variance: http://en.wikipedia.org/wiki/Algorithms_for_calculating_variance#III._On-line_algorithm http://en.wikipedia.org/wiki/Algorithms_for_calculating_vari...
  • andreyf 18y ago
    Cheater.
    • fgimenez 18y ago
      Technically, I didn't give away how to do the standard deviation ;)