How to remove all the punctuation in a string? (Python)

Question

For example:

asking="hello! what's your name?"

Can I just do this?

asking.strip("!'?")

Have you looked at http://stackoverflow.com/questions/3939361/remove-specific-characters-from-a-string-in-python ? — Garrett Hyde, Apr 17 '13 at 03:34

score 22 · Accepted Answer · edited May 23 '17 at 12:10

22

A really simple implementation is:

out = "".join(c for c in asking if c not in ('!','.',':'))

and keep adding any other types of punctuation.

A more efficient way would be

import string
stringIn = "string.with.punctuation!"
out = stringIn.translate(stringIn.maketrans("",""), string.punctuation)

Edit: There is some more discussion on efficiency and other implementations here: Best way to strip punctuation from a string in Python

edited May 23 '17 at 12:10

Community

answered Apr 17 '13 at 03:36

Øyvind Robertsen

1

`strip()` won't work. See http://docs.python.org/2/library/stdtypes.html#str.strip – Brenden Brown Apr 17 '13 at 03:47
@BrendenBrown You are indeed correct. Half a year without looking at python and what do you know. Shameful edit ensuing. – Øyvind Robertsen Apr 17 '13 at 03:51
For deleting you can simplify the last line to `out = stringIn.translate(None, string.punctuation)` (see https://docs.python.org/2/library/stdtypes.html#str.translate) – asmaier Aug 06 '15 at 13:14
For Python 3, https://stackoverflow.com/a/34294398/343215 – xtian Oct 07 '18 at 22:09

score 15 · Answer 2 · answered Apr 17 '13 at 03:31

15

import string

asking = "".join(l for l in asking if l not in string.punctuation)

answered Apr 17 '13 at 03:31

thkang

score 0 · Answer 3 · answered Apr 17 '13 at 03:35

0

This works, but there might be better solutions.

asking="hello! what's your name?"
asking = ''.join([c for c in asking if c not in ('!', '?')])
print asking

answered Apr 17 '13 at 03:35

marcin_koss

you don't need the inner list in this scenario, and this will return `'hellowhat'syourname'`. – Burhan Khalid Apr 17 '13 at 04:36
@BurhanKhalid You're right inner list is not needed but the output is correct. – marcin_koss Apr 20 '13 at 02:06

score 0 · Answer 4 · answered Apr 17 '13 at 03:43

0

Strip won't work. It only removes leading and trailing instances, not everything in between: http://docs.python.org/2/library/stdtypes.html#str.strip

Having fun with filter:

import string
asking = "hello! what's your name?"
predicate = lambda x:x not in string.punctuation
filter(predicate, asking)

answered Apr 17 '13 at 03:43

Brenden Brown

.It is important to wrap `list()` around the entire `filter()` function if you're using Python 3.x, as many built-in functions no longer return `lists` but special `iterable` objects. Also, you seem to have overlooked putting `input` (or `raw_input` for Python 2.x) around the string in the second line, and you should have put something like `asking = ...` for the final line. – SimonT Apr 17 '13 at 03:45
1

Looks like this approach is discouraged in 3.x: http://stackoverflow.com/questions/13638898/how-to-use-filter-map-and-reduce-in-python-3-3-0 – Brenden Brown Apr 17 '13 at 03:49
`filter` is ugly and slow when you have to use a `lambda` with it, unfortunately your alternative is `''.join(ifilterfalse(partial(contains, punctuation), asking))` – jamylak Apr 17 '13 at 05:03

4 Answers4