I have a file full of data in columns
sarah mark john
10 20 5
x y z
I want to sort the data so the columns stay intact but the second row is in increasing order so it looks like this:
john sarah mark
5 10 20
z x y
I've been looking at the sort command but have only been able to find vertical sorting, not horizontal. I'm happy to use any tool, any help is appreciated. Thank you!
Let's create a function to transpose a file (make rows become columns, and columns become rows):
transpose () {
awk '{for (i=1; i<=NF; i++) a[i,NR]=$i; max=(max<NF?NF:max)}
END {for (i=1; i<=max; i++)
{for (j=1; j<=NR; j++)
printf "%s%s", a[i,j], (j<NR?OFS:ORS)
}
}'
}
This just loads all the data into a bidimensional array a[line,column] and then prints it back as a[column,line], so that it transposes the given input. The wrapper transpose () { } is used to store it as a bash function. You just need to copy paste it in your shell (or in ~/.bashrc if you want it to be a permanent function, available any time you open a session).
Then, by using it, we can easily solve the problem by using sort -n -k2: sort numerically based on column 2. Then, transpose back.
$ cat a | transpose | sort -n -k2 | transpose
john sarah mark
5 10 20
z x y
In case you want to have a nice format as final output, just pipe to column like this:
$ cat a | transpose | sort -n -k2 | transpose | column -t
john sarah mark
5 10 20
z x y
Step by step:
$ cat a | transpose
sarah 10 x
mark 20 y
john 5 z
$ cat a | transpose | sort -n -k2
john 5 z
sarah 10 x
mark 20 y
$ cat a | transpose | sort -n -k2 | transpose
john sarah mark
5 10 20
z x y
Coming from a duplicate question, this would sort the columns by the first row:
#!/bin/bash
input="$1"
order=$((for i in $(head -1 $input); do echo $i; done) | nl | sort -k2 | cut -f1)
grep ^ $input | (while read line
do
read -a columns <<< "${line%"${line##*[![:space:]]}"}"
orderedline=()
for i in ${order[@]}
do
orderedline+=("${columns[$i - 1]}")
done
line=$(printf "\t%s" "${orderedline[@]}")
echo ${line:1}
done)
To sort by second row, replace head -1 $input with head -2 $input | tail -1. If the sort should be numeric, put in sort -n -k2 instead of sort -k2.
Good one-liner gets the job done:
perl -ane '$,=" "; print sort @F; print "\n";' file
I found it here: http://www.unix.com/unix-for-advanced-and-expert-users/36039-horizontal-sorting-lines-file-sed-implementation.html
