#!/bin/awk -f

#it evaluates average and standard variation of the average
#col is the column we are interested into
#sum keeps the sum of all the values in this column
#sum2 keeps the sums of the squared values
#N keeps the number of lines

BEGIN{sum=sum2=N=0}
{
if (NF != 0)
{
	sum+=$col;
	sum2+=$col*$col;
	N++;
}
}
END{print sum/N, sqrt((sum2-sum*sum/N)/(N * (N-1)));}