from a column, take each 3 values and put them in a row

Question

I’d like to accomplish this with a shell script. Here’s what my file looks like:

1
2
3
4
5
6
7
8
9

I want to convert it to be:

1 2 3
4 5 6
7 8 9

It's bigger than that, so I need something generic that works for a long file.

Thanks!

Answer 1

Here is one way:

awk 'NR%3!=0{printf "%s ",$1;next}1' inputFile

Answer 2

You can do that with paste, for example:

seq 9 | paste - - - -d ' '

The 3 dashes are to have 3 columns. You add or remove dashes to have more or fewer columns.

The -d ' ' is to separate the columns by space, because the default is tab.