Need to learn how to calculate averages for scripting

[Wilson David]

I have some sar data which looks like this:

c39t1d1 10.1
c39t1d1 10.7
c39t1d1 11.0
c39t1d4 10.6
c39t1d4 10.8
c39t1d7 11.1
c39t1d7 11.4
c39t1d7 11.5
c39t1d7 16.3
c40t1d3 10.0
c40t1d3 10.1
c40t1d3 10.2
c40t1d3 10.2
c40t1d3 10.3
c40t1d3 10.1

I am not able to figure out how to calculate averages for each cXtXdX. Can somebody help a
newbie?

[Dennis Handly · Accepted solution]

If they are not sorted, you'll need to sort the input:
sort sar_data | awk '
BEGIN { getline; disk=$1; sum=$2; count=1 }
{
if ($1 == disk) {
sum += $2
++count
} else {
print disk, sum / count
disk=$1; sum=$2; count=1
}
}
END { print disk, sum / count } '

[Wilson David]

Perfect !! It solves a big headache for me. Thank you. Assigning 10 points.

[Suraj K Sankari]

Hi,

If you want to take the average of all data
so here is the solution:

awk '{ print $2}'tmp1.out
ln=`wc -l tmp1.out| awk '{print $1}'`
if test $ln -ne 0
then
tot=0
for i in `cat tmp1.out`
do
tot=`echo $tot + $i | bc -l`
done
avg=`echo $tot / $ln | bc -l`
fi
printf "SAR : %.2f\n" $avg
rm tmp1.out

Suraj

[Dennis Handly]

>Suraj: If you want to take the average of all data

awk handles that too:
awk '
{
sum += $2
}
END { print sum / NR } ' sar_data

[Suraj K Sankari]

Hi Dennis,

Really it is a nice code.

Suraj