#037 by Numbers
Sorting text numerically in the shell using the special “version sort” mode of the sort utility.
Notes
Version strings and other text with embedded integers don’t sort nicely by default, so natural alphabetical sorting will mess us up.
Generating some version numbers to be sorted:
$ printf "v1.%d.0\n" $(seq 20 -1 0) > version_strings.txt
$ cat version_strings.txt
v1.20.0
v1.19.0
v1.18.0
v1.17.0
v1.16.0
v1.15.0
v1.14.0
v1.13.0
v1.12.0
v1.11.0
v1.10.0
v1.9.0
v1.8.0
v1.7.0
v1.6.0
v1.5.0
v1.4.0
v1.3.0
v1.2.0
v1.1.0
v1.0.0
Piping this through sort mixes this up as would be expected:
$ cat version_strings.txt | sort
v1.0.0
v1.1.0
v1.10.0
v1.11.0
v1.12.0
v1.13.0
v1.14.0
v1.15.0
v1.16.0
v1.17.0
v1.18.0
v1.19.0
v1.2.0
v1.20.0
v1.3.0
v1.4.0
v1.5.0
v1.6.0
v1.7.0
v1.8.0
v1.9.0
Howerver sort has a special “version sort” mode --version-sort or -V that
magically handles this correctly:
$ cat version_strings.txt | sort -V
v1.0.0
v1.1.0
v1.2.0
v1.3.0
v1.4.0
v1.5.0
v1.6.0
v1.7.0
v1.8.0
v1.9.0
v1.10.0
v1.11.0
v1.12.0
v1.13.0
v1.14.0
v1.15.0
v1.16.0
v1.17.0
v1.18.0
v1.19.0
v1.20.0
Although intend for sorting version srtings, it handles many simple integer sort tasks:
$ printf "dog-%d.txt\n" $(seq 20 -1 0) > numbered_strings.txt
$ printf "cat-%d.txt\n" $(seq 20 -1 0) >> numbered_strings.txt
$ cat numbered_strings.txt
dog-20.txt
dog-19.txt
dog-18.txt
dog-17.txt
dog-16.txt
dog-15.txt
dog-14.txt
dog-13.txt
dog-12.txt
dog-11.txt
dog-10.txt
dog-9.txt
dog-8.txt
dog-7.txt
dog-6.txt
dog-5.txt
dog-4.txt
dog-3.txt
dog-2.txt
dog-1.txt
dog-0.txt
cat-20.txt
cat-19.txt
cat-18.txt
cat-17.txt
cat-16.txt
cat-15.txt
cat-14.txt
cat-13.txt
cat-12.txt
cat-11.txt
cat-10.txt
cat-9.txt
cat-8.txt
cat-7.txt
cat-6.txt
cat-5.txt
cat-4.txt
cat-3.txt
cat-2.txt
cat-1.txt
cat-0.txt
Sorting by version produces the expected result:
$ cat numbered_strings.txt | sort -V
cat-0.txt
cat-1.txt
cat-2.txt
cat-3.txt
cat-4.txt
cat-5.txt
cat-6.txt
cat-7.txt
cat-8.txt
cat-9.txt
cat-10.txt
cat-11.txt
cat-12.txt
cat-13.txt
cat-14.txt
cat-15.txt
cat-16.txt
cat-17.txt
cat-18.txt
cat-19.txt
cat-20.txt
dog-0.txt
dog-1.txt
dog-2.txt
dog-3.txt
dog-4.txt
dog-5.txt
dog-6.txt
dog-7.txt
dog-8.txt
dog-9.txt
dog-10.txt
dog-11.txt
dog-12.txt
dog-13.txt
dog-14.txt
dog-15.txt
dog-16.txt
dog-17.txt
dog-18.txt
dog-19.txt
dog-20.txt
Credits and References
- sort man page
- bash: sorting strings with numbers