Edit Text format (probably with shell script)

Question

I'm trying to write a script to edit the format of a text file. I got a file with coordinates in the form

x: 123
y: 456
x: 789
y: 012
...

but need it in the form

123 456 i
789 012 i
...

Kind of like here Edit text format with shell script , just the other way round and a little more ;)

Do u guys have any ideas how i can achieve this?

Answer 1

A simple bash script using a counter to toggle printing after read of every 2 lines can suit your need. Just pass the data file as argument 1:

#!/bin/bash

declare -i cnt=0

while read -r line || [ -n "$line" ]; do
    array+=( ${line##* } )                              # read values into array
    ((cnt++))                                           # increase counter
    if [ "$cnt" -eq 2 ]; then                           # if count = 2
        printf "%s %s i\n" "${array[0]}" "${array[1]}"  # print both array values
        cnt=0                                           # reset count to 0
        unset array                                     # unset array
    fi
done <"$1"

output

123 456 i
789 012 i

Answer 2

You could use something like this:

awk 'NR>1&&NR%2{print a[1],a[2],"i";i=0}{a[++i]=$2}END{print a[1],a[2],"i"}' file

The array a contains the contents of the previous two lines. Ignoring the first line, when the line number is odd (ie when NR%2 is 1), print the last two lines, followed by "i". At the end, print the last two lines.

Testing it out:

$ awk 'NR>1&&NR%2{print a[1],a[2],"i";i=0}{a[++i]=$2}END{print a[1],a[2],"i"}' file
123 456 i
789 012 i

Answer 3

You could use awk :

$ awk '$1 == "x:"{line=$2}$1 == "y:"{line=line FS $2 FS "i"; print line}' file
123 456 i
789 012 i

Alternatively, a read loop:

while read -ra line; do
    case ${line[0]} in 
        x:)
            new_line=${line[1]}
            ;;
        y:)
            new_line+=" ${line[1]} i"
            echo $new_line
            ;;
    esac
done < file