fast way to remove lowercase substrings from string?

Question

What\'s an efficient way in Python (plain or using numpy) to remove all lowercase substring from a string s?

s = \"FOObarFOOObBAR\"
remove_lowe         


        

Answer 1

My first approach would be ''.join(x for x in s if not x.islower())

If you need speed use mgilson answer, it is a lot faster.

>>> timeit.timeit("''.join(x for x in 'FOOBarBaz' if not x.islower())")
3.318969964981079

>>> timeit.timeit("'FOOBarBaz'.translate(None, string.ascii_lowercase)", "import string")
0.5369198322296143

>>> timeit.timeit("re.sub('[a-z]', '', 'FOOBarBaz')", "import re")
3.631659984588623

>>> timeit.timeit("r.sub('', 'FOOBarBaz')", "import re; r = re.compile('[a-z]')")
1.9642360210418701

>>> timeit.timeit("''.join(x for x in 'FOOBarBaz' if x not in lowercase)", "lowercase = set('abcdefghijklmnopqrstuvwxyz')")
2.9605889320373535