Find total of a column of numbers with BASH

Problem: Find total of numbers in a file.

File 1:

aaa:23
bb:2
ccc:98
.
.
.

File 2:

23,aaa
2,bb
98,ccc
.
.
.

File 3:

aaa,23,aaa
ccc,2,bb
bb,98,ccc
.
.
.

Function to find the total

#!/usr/bin/env bash
 
function sum_it_up(){
  file="${1}"
  delimiter=${2:-":"}
  field=${3:-"2"}
  sum=0
  ints=($(cut -d ${delimiter} -f"${field}" "${file}"))
  for num in "${ints[@]}";do ((sum+=num)); done; echo $sum;
}

sum_up "${1}" "${2}" "${3}"

Usage for File 1:

$ ./sum_it_up.sh to_sum_up.txt

Usage for file 2:

$ to_sum_up.txt "," 1

Usage for file 3:

$ ./sum_it_up.sh to_sum_up.txt "," 2

Parameters the function accepts are: file to process, [delimiter to split columns in the file at] (default is ":"), [column number to sum up] (default is 2).

Use loop to find the total

# initial total
total=0
# column separator 
ifs=,
# column to find total of
col=col2
# data file
data_file=data

while IFS="$ifs" read -r col1 col2 col3 ; do
  (( total+=$"$col" ))
done < "$data_file"

echo $total

Use an array

# initial total
total=0
# column separator 
ifs=,
# column to find total of
index=2
# data file
data_file=data

while IFS="$ifs" read -r -a cols ; do
  (( total+=${cols[ $index - 1 ]} ))
done < "$data_file"