How to check how many times an element exists in a list [duplicate]

Question

I have a list like this:

[5,6,7,2,4,8,5,2,3]

and I want to check how many times each element exists in this list.

what is the best way to do it in Python?

Jud · Accepted Answer · 2018-12-19 22:13:05Z

14

The count() method counts the number of times an object appears in a list:

a = [5,6,7,2,4,8,5,2,3]
print a.count(5)  # prints 2

But if you're interested in the total of every object in the list, you could use the following code:

counts = {}
for n in a:
    counts[n] = counts.get(n, 0) + 1
print counts

answered Nov 23, 2013 at 19:56

Jud

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2 Comments

Why is total = counts.get(n,0) included? I get the same result either way with, or without it, so it seems like an extra step.

You're right, it is a superfluous item. I'll edit to correct.

Akavall · Accepted Answer · 2013-11-23 19:56:42Z

10

>>> from collections import Counter
>>> Counter([5,6,7,2,4,8,5,2,3])
Counter({2: 2, 5: 2, 3: 1, 4: 1, 6: 1, 7: 1, 8: 1}

answered Nov 23, 2013 at 19:56

Akavall

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