#!/bin/bash
for n in {0..50}; do sleep 1; aika1=$(date +%s.%N); sleep .1; aika2=$(date +%s.%N); Ero[$n]=$(echo "$aika2 - $aika1" | bc); echo ${Ero[$n] }; done 
echo -e ${Ero[@]/%/\\n} | awk '{sum+=$1; sumsq+=$1*$1} END {print "keskipoikkeama=" sqrt(sumsq/NR - (sum/NR)^2)}'
