Bash text matching and writing

Question

I have multiple sequenced txt-files. They have specific data which I need to gather in one output file.

For Example:

1.txt

     Colour:    Red

     Hight:     10

2.txt

     Colour:    Blue

     Hight:     12

How can I use bash commands, such as sed/grep, to search for specific words and ignore some charachters in order to get the data, and put them in one output file.

For example:

out.txt

     Colour    Hight

      Red        10

      Blue       12

Thanks for helping Anees

Answer 1

Assuming there are always 2 fields per file and always in the same order, Here's one way to do it with sed:

#!/bin/sh

printf '%s\t%s\n' Colour Hight

sed '

    / *Colour: */ {
        s///
        h
        n
    }

    / *Hight: */ {
        s///
        G
        s/\n/\t/g
    }

' "$@"

This answer uses the hold space feature of sed to save the data values from one line to the next.

We use statement grouping with { and }. All the commands in the group apply only to the addressed lines, in this case the lines selected by the patterns / *Colour */ and / *Hight */.

On both the Colour and Hight lines, we first delete the text that was matched (*Colour * or *Higth *) with s///.

On the Colour line, we then hold h the remaining text in the hold space, and then skip to the next line of input without printing (n).

On the Hight line, we get/append G the contents of the hold space to the pattern space, concatenated with a newline '\n' by sed. We then subsitute a tab \t for this newline and sed prints the output.

This answer should work with all versions of sed, whether on Linux, FreeBSD, or OS X.

Answer 2

You can put the header of the output file like
echo 'Colour Hight' > out.txt
And then for each file you can do something like:
awk '{printf $2" ";next;}' 1.txt >> out.txt
Or for all the txt files you can do:
ls *.txt | xargs awk '{printf $2" ";if (++onr%2 == 0) print "";next;}' >> out.txt