Python OrderedDict iterable over int

Question

I'm learning about dictionaries and I wrote a small bit of code and built it.

from collections import OrderedDict

d1 = OrderedDict([('a',0),('b',9),('c',8),('d',7),('e',6)])
d2 = OrderedDict([(1),(2),(3),(4),(5)])

I get the following error:

d2 = OrderedDict([(1),(2),(3),(4),(5)])
TypeError: 'int' object is not iterable

I don't understand why it isn't iterable? And what has 'int' got to do with the problem?

Thanks

`(1)` is the integer 1. OrderedDict expects two-element iterables (with a key and a value). — RemcoGerlich, Apr 02 '17 at 08:57

score 4 · Accepted Answer · answered Apr 02 '17 at 08:59

As documented here you need to provide key-value pairs to OrderedDict.

At its core, OrderedDict is a dictionary and thus needs a value to store at a key. Passing it (1) is wrong because:

>>a = (1)
>>type(a)
<class 'int'>

So, (1) is not a tuple but an integer object.

frederick99 · Answer 2 · 2017-04-02T09:07:11.223

3

OrderedDicts (or any sub-class of dict for that matter) are a set of key-value pairs.

>>> d1 = OrderedDict([('a',0),('b',9),('c',8),('d',7),('e',6)])
>>> d1['b']
9

The following statement does not provide any such pairs.

d2 = OrderedDict([(1),(2),(3),(4),(5)])

Also note that
(1) is an int.
(1,) is a tuple.

edited Apr 02 '17 at 09:07

answered Apr 02 '17 at 08:57

frederick99

score 1 · Answer 3 · answered Apr 02 '17 at 08:59

1

The list elements should be a tuple of 2 items (one key and another value).

(1) becomes 1 an int. So what python is doing is it is trying to split it into key-value pair. So you get that error.

answered Apr 02 '17 at 08:59

3 Answers3