Compute average and standard deviation with awk

Question

I have a \'file.dat\' with 24 (rows) x 16 (columns) data.

I have already tested the following awk script that computes de average of each column.

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Answer 1

To simply calculate the population standard deviation of a list of numbers, you can use a command like this:

awk '{x+=$0;y+=$0^2}END{print sqrt(y/NR-(x/NR)^2)}'

Or this calculates the sample standard deviation:

awk '{sum+=$0;a[NR]=$0}END{for(i in a)y+=(a[i]-(sum/NR))^2;print sqrt(y/(NR-1))}'

^ is in POSIX. ** is supported by gawk and nawk but not by mawk.