Commands by 123nor (1)

  • Display the standard deviation of a column of numbers with awk

    I was concerned that the other scripts didn't use the correct order of operations for the calculation. Variance needs to be squared before being summed, then divided by NR and then square rooted. Not sure if this method is correct but this is what I came up with. I think it works correctly but I'm not totally sure. If anyone could critique it that would be great.


    0
    awk '{delta=$1; avg+=$1/NR;} END {print "stdev = " sqrt(((delta-avg)^2)/NR);}'
    123nor · 2016-04-19 08:49:49 12

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