Python - Capitalize only first letter of each word in a string

Question

I want to check if the first character of first word is capitalized, if not, then capitalize it leaving rest of the string's casing intact.

I've tried the following method:

import re
p = re.compile(r'((?<=[\.\?!]\s)(\w+)|(^\w+))')
def cap(match):
    return(match.group().capitalize())

p.sub(cap, 'CBH1 protein was analyzed. to evaluate the report')

>>> Output : Cbh1 protein was analyzed. To evaluate the report

While this output is nearly correct, I expect the initial Cbh1 to be CBH1. Any suggestions?

Answer 1

This isn't a perfect match for any of the builtin str methods: .title() and .capitalize() will lowercase all letters after the first, while .upper() will capitalize everything.

It's not elegant, but you can just explicitly capitalize the first letter and append the rest:

def cap(match):
    grp = match.group()
    return grp[0].upper() + grp[1:]

>>> p.sub(cap, 'CBH1 protein was analyzed. to evaluate the report')
'CBH1 protein was analyzed. To evaluate the report'