Extracting all strings of length 2 with Re.Findall

Question

I would like to extract all 2-letter strings from a text with a regular expression, for example :

just a test

would get me ju, us, st, te, es, st

I tried using : re.findall(r'\w{2}',text) but it only divides the words into 2-letter strings and gives me ju, st, te, st

Thank you very much in advance for your help.

Use [`re.findall(r'(?=(\w{2}))',text)`](http://ideone.com/XucVPm). — Wiktor Stribiżew, Feb 26 '17 at 22:10
without regex: `print(["".join(x) for w in "just a test".split() if len(w)>1 for x in zip(w,w[1:])])` — Jean-François Fabre, Feb 26 '17 at 22:13
@sin: he marked as duplicate then commented (not answered) to help the OP in his specific question. I just wished I could post my non-regex solution. — Jean-François Fabre, Feb 26 '17 at 22:14
@BillBell actually I could have reopened the question by myself, but I tend to avoid that by respect of other python gold badge holders. I guess Wiktor did that, so now I posted my answer. — Jean-François Fabre, Feb 26 '17 at 22:59
@WiktorStribiżew since it's not a dupe anymore why don't you answer? you commented first with a valid snippet. — Jean-François Fabre, Feb 26 '17 at 23:00
Possible duplicate of [Python regex find all overlapping matches?](http://stackoverflow.com/questions/5616822/python-regex-find-all-overlapping-matches) — 4castle, Feb 26 '17 at 23:13

score 2 · Answer 1 · answered Feb 26 '17 at 22:57

I'll leave the regex solutions to regex experts (which I'm not), since it can be done without regex quite simply in a one-liner list comprehension:

s = "just a test"
result = ["".join(x)  for w in s.split() if len(w)>1 for x in zip(w,w[1:])]

print(result)

result:

['ju', 'us', 'st', 'te', 'es', 'st']

Just split the words, filtering out words with less than 2 characters, and interleave them against their shifted copy using zip

only works if there's no punctuation of course.

1 Answers1