Help with sort command

Corrado · 06-26-2016, 07:06 PM

I've been struggling to sort a file with multiple columns. Maybe somebody could help me out?

What I am trying to do is sort the times in the last column numerically in reverse. The delimiter being spaces between columns is not always equal in number.

Does anyone know a good website with explains and gives examples of various commands? The man pages are sometimes Greek to me.

Quote:

DATE & TIME HOST RELEASE LS TIME
06-26 16:12:02 349 rhel-6.6 0:03.00
06-26 16:12:08 351 rhel-6.6 0:05.65
06-26 16:12:15 352 rhel-6.6 0:06.09
06-26 16:12:22 353 rhel-6.7 0:06.38
06-26 16:12:29 355 rhel-6.6 0:05.33
06-26 16:12:36 356 rhel-6.6 0:02.60
06-26 16:12:39 357 rhel-6.6 0:06.35
06-26 16:12:46 358 rhel-6.6 0:03.21

tayfie · 06-26-2016, 09:11 PM

If you don't care about preserving the spaces, it makes everything easier to get rid of the extras. Otherwise, you are looking at some scripting in the language of your choice.

Code:

tr -s ' ' < file.txt >newfile.txt

The two important commands for dealing with column manipulation are cut and paste.

Code:

cut -d ' ' -f5 newfile.txt | paste - newfile.txt | sort -r | cut -d ' ' -f 2- >sorted.txt

sorted.txt contains the result you want.

What this does is paste the desired column on the front, sort that, and cut it off again.

As for web examples, I'm not sure how advanced you had in mind. Mostly I just google the command name I want to know about.

syg00 · 06-26-2016, 09:16 PM

I can't believe a search on "linux sort examples" didn't turn up a bunch of useful sites.

Sort doesn't care about the number of consecutive separators - it senses the transition from whitespace to non. Sort fields are called "keys", so you use -k for that, and -r to reverse the sort. All in the manpage, although as is normally the case "info sort" is more expansive.
Header/footer lines are usually a problem, but you might get lucky.

Edit: ... ahh, now I see the problem. Check out the "-V" parameter. Very useful on occasions.

Turbocapitalist · 06-27-2016, 07:25 AM

Quote:

Originally Posted by Corrado

The delimiter being spaces between columns is not always equal in number.

Can you post some examples of the rows with different spacings? With "sort" the amount of whitespace is not as important as if there are empty columns.

Otherwise, syg00 suggests there is -r and -k. The manual page for "sort" is quite hard to follow, but with the data above you would use -rk 5,5 because the colons throw off any use of the numeric option (-n) and the numbers are in order.

sundialsvcs · 06-27-2016, 07:53 AM

Yes, it would be very helpful if you could post both a (of course, "sanitized") version of the actual data, showing any "different in number" differences that you speak of.

Then, show us the actual sort command that you are using, and carefully tell us, in your own words, how you intend for this file to be correctly sorted.

HMW · 06-27-2016, 09:43 AM

I don't get it... as long as the actual columns are not different, this seems to work (or?!?):

Code:

echo "06-26 16:12:02 349 rhel-6.6 0:03.00
06-26 16:12:08 351 rhel-6.6 0:05.65
06-26 16:12:15 352 rhel-6.6 0:06.09
06-26 16:12:22 353 rhel-6.7 0:06.38
06-26 16:12:29 355 rhel-6.6 0:05.33
06-26 16:12:36 356 rhel-6.6 0:02.60
06-26 16:12:39 357 rhel-6.6 0:06.35
06-26 16:12:46 358 rhel-6.6 0:03.21" | sort -k 5 -r
06-26 16:12:22 353 rhel-6.7 0:06.38
06-26 16:12:39 357 rhel-6.6 0:06.35
06-26 16:12:15 352 rhel-6.6 0:06.09
06-26 16:12:08 351 rhel-6.6 0:05.65
06-26 16:12:29 355 rhel-6.6 0:05.33
06-26 16:12:46 358 rhel-6.6 0:03.21
06-26 16:12:02 349 rhel-6.6 0:03.00
06-26 16:12:36 356 rhel-6.6 0:02.60

Then again, I am probably missing what the OP really wants here.

Best regards,
HMW