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Split list of names into alphabetic dictionary, in Python

List.

['Chro开发者_开发技巧me', 'Chromium', 'Google', 'Python']

Result.

{'C': ['Chrome', 'Chromium'], 'G': ['Google'], 'P': ['Python']}

I can make it work like this.

alphabet = dict()
for name in ['Chrome', 'Chromium', 'Google', 'Python']:
  character = name[:1].upper()
  if not character in alphabet:
    alphabet[character] = list()
  alphabet[character].append(name)

It is probably a bit faster to pre-populate the dictionary with A-Z, to save the key check on every name, and then afterwards delete keys with empty lists. I'm not sure either is the best solution though.

Is there a pythonic way to do this?


Anything wrong with this? I agree with Antoine, the oneliner solution is rather cryptic.

import collections

alphabet = collections.defaultdict(list)
for word in words:
    alphabet[word[0].upper()].append(word)


I don't know if it's Pythonic, but it's more succinct:

import itertools
def keyfunc(x):
   return x[:1].upper()
l = ['Chrome', 'Chromium', 'Google', 'Python']
l.sort(key=keyfunc)
dict((key, list(value)) for (key,value) in itertools.groupby(l, keyfunc))

EDIT 2 made it less succinct than previous version, more readable and more correct (groupby works as intended only on sorted lists)

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