Remove word from string start with specific characters

Question

I have the following string:

my_string = "This is an example string, ex , excatly , index , hyperextension"

I want to remove all words that start with ex in Python.

So the result I want would be:

remove_words_that_start_with_ex("my_string")
print(my_string)

Desired result:

This is an string, , , index , hyperextension

I tried doing something like this:

main_str = " ".join(filter(lambda x:x[0,1]!='ex', main_str.split()))

but it only works with one character, not 2 ("ex").

Answer 1

You can use python's built-in startswith method like so:

>>> my_string = "This is an example string, ex , excatly , index , hyperextension"
>>>
>>> print ' '.join(x for x in my_string.split() if not x.startswith('ex'))
This is an string, , , index , hyperextension

Now in case you just want to fix your lambda, here is a fix:

>>> print " ".join(filter(lambda x: x[0:2]!='ex', my_string.split()))
This is an string, , , index , hyperextension

Answer 2

You can use re.sub to do this

>>> import re
>>> my_string = "This is an example string, ex , excatly , index , hyperextension"
>>> re.sub('(?:\s)ex[^, ]*', '', my_string)
'This is an string, , , index , hyperextension'

Answer 3

You can use re.sub :

import re
my_string = "This is an example string, ex , excatly , index , hyperextension"
final_string = re.sub('(?<=\s)ex[\w]+|(?<=^)ex[\w]+', '', my_string)

Output:

'This is an  string, ex ,  , index , hyperextension'

Or, by providing a lambda :

final_string = re.sub('\w+', lambda x:'' if x.group().startswith('ex') else x.group(), my_string)

Output:

'This is an  string,  ,  , index , hyperextension'