Question

I have quite large amount of text which include control charachters like \n \t and \r.
I need to replace them with a simple space–> ” “. What is the fastest way to do this?
Thanks

Answer 1

I think the fastest way is to use str.translate():

import string
s = "a\nb\rc\td"
print s.translate(string.maketrans("\n\t\r", "   "))

prints

a b c d

EDIT: As this once again turned into a discussion about performance, here some numbers. For long strings, translate() is way faster than using regular expressions:

s = "a\nb\rc\td " * 1250000

regex = re.compile(r'[\n\r\t]')
%timeit t = regex.sub(" ", s)
# 1 loops, best of 3: 1.19 s per loop

table = string.maketrans("\n\t\r", "   ")
%timeit s.translate(table)
# 10 loops, best of 3: 29.3 ms per loop

That’s about a factor 40.