Script to find the average of a given column and also for specified number of rows??

Shell Programming and Scripting
1

Hi friends
I have 100 files in my directory. Each file look like this..

     Temp1 Temp2 Temp3

MAS 1 2 3
MAS 4 5 6
MAS 7 8 9
Delhi 10 11 12
Delhi 13 14 15
Delhi 16 17 18
Delhi 20 21 19
Mumbai 22 46 56
Mumbai 67 34 54
..................................
.................................. so on.

I need a script which gives gives average of the column2 Temp2 for a given row(s) e.g. Delhi or MAS
I got an awk script some thing like below from this unix forum but it is giving the average of all the rows.

$ (cd awkdir ; ls | while read filename ; do awk '{sum+=$3} END { print "Average for " FILENAME " = ",sum/NR}' $filename ; done)

Can anyone please add the grep " MAS/Delhi/.... so on" command to the existing script so that I will get my desired output...

Many thanks in advance to evryone.. This is my first posting..

2

Hope this helps:

awk '/Delhi/ {sum+=$3; divby++} END { print "Average for " FILENAME " = ",sum/divby}' FILENAME=foo foo

For a little flexibility, you can also try this:

awk '$1==searchme {sum+=$3; divby++} END { print "Average for " FILENAME " = ",sum/divby}' FILENAME=foo searchme=Delhi foo
3 
for filename in *
do
  printf "Average for %s = " "$filename"
  awk '/^MAS/ || /^Delhi/ { ++n; sum += $3 }
        END { print sum / n }
  ' "$filename"
done
4

Hi Johnson Thanks for your quick reply...
But there is one correction in my input data..
My data looks like this..

SNO Day CITY Col1 Col2 Col3 ........... So on
1 02/01/09 MAS 1 2 3
2 02/01/09 MAS 4 5 6
3 02/01/09 MAS 7 8 9
4 02/01/09 Delhi 10 11 12
5 02/01/09 Delhi 13 14 15
6 02/01/09 Delhi 16 17 18
7 02/01/09 Delhi 20 21 19
8 02/01/09 Mumbai 22 46 56
9 02/01/09 Mumbai 67 34 54
......................................................................... an so on.

I need to find the average of column 6(for example, there are around 40 columns in my files) for only the rows which contains Delhi in a given column(in this case it is col3). I hope you understand what I am asking.. It will be a great help for me if you can modified your previous script...

5

Hi Reddy,
Johnson's script absolutely fine :
for filename in *
do
printf "Average for %s = " "$filename"
awk '/^MAS/ || /^Delhi/ { ++n; sum += $3 }
END { print sum / n }
' "$filename"
done

For the change in your file content just change the line :
awk '/^MAS/ || /^Delhi/ { ++n; sum += $3 }with
awk '/^MAS/ || /^Delhi/ { ++n; sum += $6 } #as u need average of column 6....So that part of the code is dealing with the column number....as u should understand from the Average formula.....:slight_smile: