Why does sorted() put 9 after 84 and 878?

Question

numbers = ['3','1','6','5','4','4','3','2','1','4','3','5','4','9','84','7','878','6']
counts = dict()
for number in numbers:
    counts[number] = counts.get(number, 0) + 1
print counts

for k,v in sorted(counts.items()):
    print k,v

Output:

{'878': 1, '1': 2, '3': 3, '2': 1, '5': 2, '4': 4, '7': 1, '6': 2, '9': 1, '84': 1}
1 2
2 1
3 3
4 4
5 2
6 2
7 1
84 1
878 1
9 1

Why is 9 the last one instead of 84 and 878?

Because `'9' > '878'` is True. You need to convert keys to integers first. — vaultah, Apr 20 '16 at 15:24
You're sorting strings, not numbers. If you want a numeric sort, convert the strings to numbers first. — Tom Karzes, Apr 20 '16 at 15:28
Not an answer to the question, but you could also use `collections.Counter` — tobias_k, Apr 20 '16 at 15:29

score 3 · Accepted Answer · answered Apr 20 '16 at 15:25

3

Because it compares lexicograhically. And '8' of '878' comes before '9' in lexicographical order. You are comparing as strings and not integers.

answered Apr 20 '16 at 15:25

Priyansh Goel

2,660
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score 0 · Answer 2 · answered Apr 20 '16 at 15:28

Because you have put your numbers in as strings they are sorted lexicographically which puts things in order by the characters of the string. So '9' is compared to the first '8' of '898' and thus comes after it.

You can get a more natural sort order by using a package such as Natsort which can be installed via PyPi.

score -1 · Answer 3 · answered Apr 20 '16 at 15:27

-1

Because you are comparing strings and you want to compare numbers.

answered Apr 20 '16 at 15:27

Mad Wombat

14,490
14
73
109

Why does sorted() put 9 after 84 and 878?

3 Answers3