Hi i am trying to find all 3 and 4-character length words in my file (which is huge and has alot of entries in it, a big fat wordlist!).

My attempt with this regular expression (which I thought should work, found something on length search here: http://www.gammon.com.au/mushclient/regexp.htm {n,m} )

cat sorted_noapostrophe.txt| grep '.{3,4}'

but it returns no results?

Also to find any words starting with 'f' which are between 3 and 5 characters (inclusive) long, how can this be done?

Any help would be greatly appreciated!

gvanto
regex noob :-)

You are on sort of the right track. The use of {3,4} is actually an extend regular expression syntax which means you either need to use egrep or grep -E.
The problem you will find is that as dot (.) matches anything your idea will also match the following:
All of these have 3 - 4 of any character.

Hi,

Hope this helps.

Thanks much guys! This ended up working fine (druuna slight mod to yours, I need stuff like this too: 'état' which :alpha doesn't return)

I actually used grep -e before (thinking it was extended grep issue) but should have been -E (and -o and -w)

oh hang on, just noticed, the above command also returns 2-letter words?!
(the file contains only single words, all terminated by a newline ... is newline then also considered a character?

This seems to work same as druuna's: grep -owE "\w{3,4}" sorted_noapostrophe.txt but now I dont have 'état' ... its OK)

Thanks a million!
gvanto

Hi,

\w equals [[:alnum:]] which equals [0-9A-Za-z]. That explains the inclusion of normal chars and not état.

You might want to look into equivalence classes, but I do believe they can only be assigned 1 letter at the time.... You end up with something like this:Needs to be expanded for the o/u/c/etc, but you get the idea, I hope

BTW the "pipes" (..|..|..) OR all the reg exp together.