CODEWITHSUNDEEP
shellunixawk
mikro098
mikro098

Reputation: 2353

Multiple arguments in shell script using awk

I've to make a script which will be able to sum the columns. The file looks like that:

1 2 3
1 2 
1

While executing script without the argument ./sum.sh I get the sum of all the columns so the answer is 10. But I have to make it add only certain columns. For example ./sum.sh 1 3 should sum first and third column and give 6.

My code:

sum=0

if [[ $# -eq 0 ]]; then
  awk '{for(i=1;i<=NF;i++) sum+=$i;}; END {print sum}' plik.txt
  else
    exit 0;
fi

while [ $# -gt 0 ]
do
    awk '{sum +="$1"} END {print sum}' plik.txt
    shift
done

I think that I'm quite close to the solution, but something must be missing.

Upvotes: 0

Views: 95

Answers (3)

karakfa
karakfa

Reputation: 67547

here is a combination of your script and Kent's solution

#!/bin/bash

file=plik.txt

if [ $# -eq 0 ];
    then
        awk     '{for(i=1;i<=NF;i++) sum+=$i} 
             END {print sum}' "$file"
    else
        awk -v cols="$*" 'BEGIN {split(cols,cs)}
                                {for(c in cs) sum+=$cs[c]}
                          END   {print sum}' "$file"    
fi

in action

$ ./sum.sh 1
3

$ ./sum.sh
10

$ ./sum.sh 1 3
6

$ ./sum.sh 1 2
7

$ ./sum.sh 1 2 3 4
10

$ ./sum.sh 1 2 3
10

Upvotes: 1

Kent
Kent

Reputation: 195229

This one liner should work:

awk -v c="1 3" 'BEGIN{split(c,cols)}
               {for(x in cols)s+=$cols[x]}END{print "Sum:"s}' file

Note the c="1 3" means the columns you want to do sum, space separated. It could be set by shell script variable: -v c="$var", the awk will do the calculation and output.

With your example file, the above one-liner outputs:

Sum:6

Upvotes: 2

Yaron
Yaron

Reputation: 1242

This is what I came up with, no bash conditions required:

awk 'BEGIN{sum=0} {if(NF==1) sum+=$1;else for(i=1;i<=NF;i++) sum+=$i;} END{print sum}' plik.txt

Upvotes: 0

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