How to sort keys of a dictionnary posted in url?

Question

I have this dict posted in request.POST:

<QueryDict: {u'csrfmiddlewaretoken': [u'fhvpUorGAl7LMv4JIJRd0WOEHPkKn6iN'], u'actor_1': [u'first_actor'], u'actor_5': [u'second_actor'], u'actor_55': [u'third_actor'], u'actor_2': [u'fourth_actor']}>

i want to sort it by the keys to have

<QueryDict: {u'actor_1': [u'first_actor'], u'actor_2': [u'fourth_actor'], u'actor_5': [u'second_actor'], u'actor_55': [u'third_actor'], u'csrfmiddlewaretoken': [u'fhvpUorGAl7LMv4JIJRd0WOEHPkKn6iN']}>

Is there a way to sort keys (not values) of a dictionnary ?

@tea2code that is sorting a dictionary by the values, not the keys? So not quite the same question as far as I can see — Will, Sep 05 '13 at 10:58
I copied the wrong link sorry. The correct one: http://stackoverflow.com/questions/9001509/python-dictionary-sort-by-key — tea2code, Sep 05 '13 at 10:59

score 4 · Accepted Answer · answered Sep 05 '13 at 11:05

4

Common dicts are, as mentioned, unordered by nature, but you can use OrderedDicts.

import collections

d = {
    u'csrfmiddlewaretoken': [u'fhvpUorGAl7LMv4JIJRd0WOEHPkKn6iN'], 
    u'actor_1': [u'first_actor'], 
    u'actor_2': [u'fourth_actor']
}

collections.OrderedDict(sorted(d.items()))

answered Sep 05 '13 at 11:05

Xevelion

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The simple way is listed in the seconde link given by tea2code: `req_posts = request.POST` `sorted_posts = sorted(req_posts.iterkeys())` – Drwhite Sep 05 '13 at 11:10

Michel Keijzers · Answer 2 · 2013-09-05T11:02:11.817

Dictionaries cannot be sorted. Instead use for example a list.

However you can print out the values sorted by using:

d = {u'csrfmiddlewaretoken': [u'fhvpUorGAl7LMv4JIJRd0WOEHPkKn6iN'], 
 u'actor_1'            : [u'first_actor'], 
 u'actor_5'            : [u'second_actor'], 
 u'actor_55'           : [u'third_actor'], 
 u'actor_2'            : [u'fourth_actor']}

keys = d.keys()
keys.sort()
for key in keys:
   print d[key]

print keys

Result:

[u'first_actor']
[u'fourth_actor']
[u'second_actor']
[u'third_actor']
[u'fhvpUorGAl7LMv4JIJRd0WOEHPkKn6iN']
[u'actor_1', u'actor_2', u'actor_5', u'actor_55', u'csrfmiddlewaretoken']

Which displays all sorted values and last line displaying the sorted keys.

score 0 · Answer 3 · edited Sep 05 '13 at 11:06

0

No. Fundamentally, the keys in a Python dictionary are unordered. check the dictionary documentation here

edited Sep 05 '13 at 11:06

a14m

7,808
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answered Sep 05 '13 at 10:57

Will

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No ! they are, see tea2code's link in comment :) – Drwhite Sep 05 '13 at 11:05
2

@Drwhite **in** a `dict`ionary keys are **not** sorted(i.e. the order in which they are displayed when printing, or yielded when iterating is pseudo-random). tea2code shows a *different* data structure, which does *not* "sort" the keys. It simply keeps track of the order in which the keys were *added* (not their alphabetical order!) – Bakuriu Sep 05 '13 at 11:31

How to sort keys of a dictionnary posted in url?

3 Answers3