pythonic dictionary counter?

Question

Easiest explained by example:

events = ['foo', 'bar', 'biz', 'foo', 'foo']
events_counter = {}
for event in events:
    if event not in events_counter: # {
        events_counter[event] = 1   # {
    else:                           # {
        events_counter[event] += 1  # {
print events_counter

# {'biz': 1, 'foo': 3, 'bar': 1}

Is there a way to implement the highlighted code in a more pythonic way? I feel like there should be a built-in function, i.e:

events_counter.count_up(event)

And yes, I do know I could just write my own procedure, thanks.

`collections.Counter` is your friend. The question is too easy — RomanPerekhrest, Jun 11 '17 at 18:33
@RomanPerekhrest The question is well formatted and clear, just because OP isn't aware of that doesn't make it a bad question necessarily. That said yeah the OP really should of found it googling. — Spencer Wieczorek, Jun 11 '17 at 18:34
@SpencerWieczorek, where did I say that it's bad? It's duplicate — RomanPerekhrest, Jun 11 '17 at 18:35
The `collections` module is fantastic and built-in to Python. One of the things it contains is a great `Counter` class, which is very flexible. You can read about the module here: https://docs.python.org/3/library/collections.html — Eric Fulmer, Jun 11 '17 at 20:38

score 7 · Accepted Answer · answered Jun 11 '17 at 18:33

7

Python has a built in Counter data structure for this:

from collections import Counter
events = ['foo', 'bar', 'biz', 'foo', 'foo']
cc = Counter(events)
print(cc)

Output:

Counter({'foo': 3, 'bar': 1, 'biz': 1})

answered Jun 11 '17 at 18:33

GWW

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ahaha apologies, I did briefly look at collections but must've missed it. – Raven Jun 11 '17 at 19:13

pythonic dictionary counter?

1 Answers1