Python strip() multiple characters?

Python

Python Problem Overview


I want to remove any brackets from a string. Why doesn't this work properly?

>>> name = "Barack (of Washington)"
>>> name = name.strip("(){}<>")
>>> print name
Barack (of Washington

Python Solutions


Solution 1 - Python

Because that's not what strip() does. It removes leading and trailing characters that are present in the argument, but not those characters in the middle of the string.

You could do:

name= name.replace('(', '').replace(')', '').replace ...

or:

name= ''.join(c for c in name if c not in '(){}<>')

or maybe use a regex:

import re
name= re.sub('[(){}<>]', '', name)

Solution 2 - Python

I did a time test here, using each method 100000 times in a loop. The results surprised me. (The results still surprise me after editing them in response to valid criticism in the comments.)

Here's the script:

import timeit

bad_chars = '(){}<>'

setup = """import re
import string
s = 'Barack (of Washington)'
bad_chars = '(){}<>'
rgx = re.compile('[%s]' % bad_chars)"""

timer = timeit.Timer('o = "".join(c for c in s if c not in bad_chars)', setup=setup)
print "List comprehension: ",  timer.timeit(100000)


timer = timeit.Timer("o= rgx.sub('', s)", setup=setup)
print "Regular expression: ", timer.timeit(100000)

timer = timeit.Timer('for c in bad_chars: s = s.replace(c, "")', setup=setup)
print "Replace in loop: ", timer.timeit(100000)

timer = timeit.Timer('s.translate(string.maketrans("", "", ), bad_chars)', setup=setup)
print "string.translate: ", timer.timeit(100000)

Here are the results:

List comprehension:  0.631745100021
Regular expression:  0.155561923981
Replace in loop:  0.235936164856
string.translate:  0.0965719223022

Results on other runs follow a similar pattern. If speed is not the primary concern, however, I still think string.translate is not the most readable; the other three are more obvious, though slower to varying degrees.

Solution 3 - Python

string.translate with table=None works fine.

>>> name = "Barack (of Washington)"
>>> name = name.translate(None, "(){}<>")
>>> print name
Barack of Washington

Solution 4 - Python

Because strip() only strips trailing and leading characters, based on what you provided. I suggest:

>>> import re
>>> name = "Barack (of Washington)"
>>> name = re.sub('[\(\)\{\}<>]', '', name)
>>> print(name)
Barack of Washington

Solution 5 - Python

strip only strips characters from the very front and back of the string.

To delete a list of characters, you could use the string's translate method:

import string
name = "Barack (of Washington)"
table = string.maketrans( '', '', )
print name.translate(table,"(){}<>")
# Barack of Washington

Solution 6 - Python

For example string s="(U+007c)"

To remove only the parentheses from s, try the below one:

import re
a=re.sub("\\(","",s)
b=re.sub("\\)","",a)
print(b)

Attributions

All content for this solution is sourced from the original question on Stackoverflow.

The content on this page is licensed under the Attribution-ShareAlike 4.0 International (CC BY-SA 4.0) license.

Content TypeOriginal AuthorOriginal Content on Stackoverflow
QuestionAP257View Question on Stackoverflow
Solution 1 - PythonbobinceView Answer on Stackoverflow
Solution 2 - PythonJasonFruitView Answer on Stackoverflow
Solution 3 - PythoncherishView Answer on Stackoverflow
Solution 4 - PythonRuelView Answer on Stackoverflow
Solution 5 - PythonunutbuView Answer on Stackoverflow
Solution 6 - PythonSiva KumarView Answer on Stackoverflow