How to get a sorted list from this dictionary with conditions?

Question

So i have this dictionary in (Python 3.x) :

dict = {
    "Gryffindor": gryffcount,
    "Ravenclaw": ravencount,
    "Hufflepuff": hufflecount,
    "Slytherin": slycount
}

gryffcount, ravencount, hufflecount and slycount are int variables.

And I want to output a list in which : - the first item should be the key for which the value is the highest - the second one should be the key for which the value is the second highest - and so on... EDIT : but if two counts are equal then the one that was mentioned first in the dictionary should appear first.

So if gryffcount == 0, ravencount == 2, hufflecount == 0, slycount == 4

I should get this list :

["Slytherin","Ravenclaw","Gryffindor","Hufflepuff"]

Assuming your dictionary is “dct”: sorted_keys = map(operator.itemgetter(0), sorted(dct.items(), key=operator.itemgetter(1))) — randomir, Jan 14 '19 at 02:18
Did you mean `["Slytherin","Ravenclaw","Gryffindor","Hufflepuff"]`? — Mad Physicist, Jan 14 '19 at 02:18
yes, and I fogot to add an additional condition. I just edited the question — Michael, Jan 14 '19 at 02:37
Hi I took time to answer your [question](https://math.stackexchange.com/questions/3196310/fundamental-theorem-of-algebra-and-quaternions) don't delete it without showing you understood and render thanks — reuns, Apr 21 '19 at 21:07

score 5 · Accepted Answer · answered Jan 14 '19 at 02:19

5

This should do it

sorted(dict, key=dict.get, reverse=True)

answered Jan 14 '19 at 02:19

BugCatcherJoe

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This is definitely the cleanest answer. – Mad Physicist Jan 14 '19 at 02:21

dtanabe · Answer 2 · 2019-01-14T02:25:05.137

0

Renaming dict to my_data to avoid clashing with the builtin dict:

my_data = {
    "Gryffindor": gryffcount,
    "Ravenclaw": ravencount,
    "Hufflepuff": hufflecount,
    "Slytherin": slycount
}

# create a new dictionary, sorted by value
# For Python 3.6+ if you're using CPython, or any version of Python 3.7+
my_data_sorted_by_value = dict(sorted(my_data.items(), key=lambda t: t[1]))

# older Pythons:
import collections
my_data_sorted_by_value = collections.OrderedDict(sorted(my_data.items(), key=lambda t: t[1]))

# and here are the keys
print(list(my_data_sorted_by_value.keys()))

edited Jan 14 '19 at 02:25

answered Jan 14 '19 at 02:16

dtanabe

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what makes you think dict(sorted_data) stays sorted? – randomir Jan 14 '19 at 02:18
1

In CPython 3.6+, they are ordered; in Python 3.7, they're ordered as part of the spec: https://stackoverflow.com/questions/39980323/are-dictionaries-ordered-in-python-3-6 – dtanabe Jan 14 '19 at 02:19
But good point; added clarifying comments and a variant that works in older Pythons. – dtanabe Jan 14 '19 at 02:20
not everybody uses cpython 3.7. and you should mention that in your answer. – randomir Jan 14 '19 at 02:20
also, result should be a list of keys, not dict. – randomir Jan 14 '19 at 02:24

How to get a sorted list from this dictionary with conditions?

2 Answers2