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

Here is some calculation I've made on a grinder data output file for a long soak test which had to be interrupted:

Standard deviation(biased) + average:

cat  | grep -v "1$" | awk -F ', '  '{   sum=sum+$5 ; sumX2+=(($5)^2)} END { printf "Average: %f. Standard Deviation: %f \n", sum/NR, sqrt(sumX2/(NR) - ((sum/NR)^2) )}'

Standard deviation(non-biased) + average:

cat   | grep -v "1$" | awk -F ', '  '{   sum=sum+$5 ; sumX2+=(($5)^2)} END { avg=sum/NR; printf "Average: %f. Standard Deviation: %f \n", avg, sqrt(sumX2/(NR-1) - 2*avg*(sum/(NR-1)) + ((NR*(avg^2))/(NR-1)))}'