Summing up an array inside of awk?

Hello Developer, Hope you guys are doing great. Today at Tutorial Guruji Official website, we are sharing the answer of Summing up an array inside of awk? without wasting too much if your time.

The question is published on September 16, 2013 by Tutorial Guruji team.

I have the following piece of code:

sum1=
sum2=    
declare -a a
echo $temp | awk '{split($0,a,","); name=a[1] ; for(i=2;i<=4;i++) sum1+=a[i] ; for(i=5;i<=7;i++) sum2+=a[i] }'

This code is not working. Here temp is a string of type:

abc,1,2,3,4,5,6

Actually I am parsing data from a file. The input file is like:

abc,1,2,3,4,5,6
de,3,5,7,8,4,2
xyz,6,5,3,7,8,2

I am reading it using

while  read temp
do
 #do something
done < sample.csv

And expected output is of the form:

Name   Sum1  Sum2
abc      6    15
de      15    14
xyz     14    17

Answer

Setting up $temp

First be sure that you’ve set up the $temp variable properly:

$ temp="abc,1,2,3,4,5,6"
$ echo "$temp"
abc,1,2,3,4,5,6

Simple example

I used the following approach to do it:

$ echo "$temp" | tr ',' 'n' | grep -v abc | awk '{sum+=$1};END{print sum}'
21

Your example

Regarding your approach you forgot to print the arrays you accumulated with an END{...} block:

$ echo "$temp" | awk '{split($0,a,","); name=a[1]
      for(i=2;i<=4;i++) sum1+=a[i] ; for(i=5;i<=7;i++) sum2+=a[i] }
      END{print sum1; print sum2}'
6
15

Saving for later

Awk doesn’t have a method for injecting results back into the parent’s shell from where it was called, so you’ll have to get a bit crafty and save it’s results to an array in Bash.

Example

$ myarr=($(echo "$temp" | awk '{split($0,a,","); name=a[1]
      for(i=2;i<=4;i++) sum1+=a[i] ; for(i=5;i<=7;i++) sum2+=a[i] }
      END{ print sum1; print sum2}'))

The above is doing this:

$ myarr=($(...awk command...))

This will result in your values from sum1 and sum2 being saved into array $myarr.

Accessing the array $myarr

They’re accessible like so:

$ echo "${myarr[@]}"
6 15

$ echo "${myarr[0]}"
6

$ echo "${myarr[1]}"
15

We are here to answer your question about   Summing up an array inside of awk?  - If you find the proper solution, please don't forgot to share this with your team members.

Summing up an array inside of awk? Code Answer