Show HN: st – simple statistics from the command line

Re:Show HN: st – simple statistics from the command line by Doches on Wednesday September 04, 2013 @08:38AM (#6327067)

If you need numerical stability, I'd use Gary Perlmann's [|stat](http://oldwww.acm.org/perlman/stat/history.html). It's older and somewhat harder to get a copy of, but it's as reliably correct as a piece of software can be...

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Re:Show HN: st – simple statistics from the command line by imurray on Wednesday September 04, 2013 @10:14AM (#6327680)

I've just had a look at the |STAT source, and it computes the variance with

        double  M       = Sum/N;                /* mean */
        double  var     = (s2 - M*Sum)/(N-1);   /* variance */

where s2 is the sum of squares. In most reasonable situations, this approach will work fine. It just doesn't take as wide a variety of inputs as is easily possible to achieve with normal floating point doubles. In fairness, the |STAT terms and conditions state:

|STAT PROGRAMS HAVE NOT BEEN VALIDATED FOR LARGE DATASETS, HIGHLY VARIABLE DATA, NOR VERY LARGE NUMBERS.

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