UNIX for Dummies Questions & Answers

How to use cut when your delimeter is either space (could be one or more) or tab.

example :-
See the data below.

Code:

A                       B                            C
                         E                            F

The first column of the second row is blank (NULL).

say, I want to cut the second field. The fields are seprated by either one or more blank space or one or more tab.

Do, I have use tr command first on the file and then pass the result to the cut command or there is any easy way in cut command itself.

Thanks
Sanjay

Personally, I would try to use awk instead of cut, especially if the data in the columns ins't lined up. If the data is lined up, why not just use cut -c?

I agree, awk would be the way to go:

awk '{print $2 }' file1 > file2

this will pull out your column B from file1 and put it into file2
(for other columns, change the $2 to what ever column # you need. (you can even pull multiple columms

If this won't work, and you still need to use cut, you can replace the spaces with a comma, or what ever delimiter you need.

Search & Replace in VI

in vi type

:%s/ /,/g This will replace all tabs with a comma

to replace multiple spaces, or multiple tabs, just put the number of spaces or tabs in the first part of the search & replace


RECON

Thanks Guys,
I guess awk command will not work perfectly here.

cat y | awk '{ print $2 }'

where y is

Code:

A       B       C
         D       E

the output is B and E, what I want is B and D.
You are right that cut -c will work perfect , If positions are known.

Change the delimiter to be a single tab. Then use cut. Below, where I type TAB, hit your TAB key.

sed 's/[ TAB][ TAB]*/TAB/g' | cut -f1-2

You can still use awk, you just need the -F option. awk -F\t '{print $2}' will give you the second column if it is truely tab delimited.

Thanks guys.