How to sort a dictionary in Python?

A dictionary is a data structure that consists of key and value pairs. We can sort a dictionary using two criteria −

Sort by key − The dictionary is sorted in ascending order of its keys. The values are not taken care of.

Sort by value − The dictionary is sorted in ascending order of the values.

Method 1 − Sort the dictionary by key

In this approach, the dictionary is sorted in ascending order of its keys.

Input:

{2:90, 1: 100, 8: 3, 5: 67, 3: 5}

Output:

{1:100, 2:90, 3:5, 5:67, 8:3}

As shown above, we can see the dictionary is sorted according to its keys.

dic={2:90, 1: 100, 8: 3, 5: 67, 3: 5}
dic2={}
for i in sorted(dic):
   dic2[i]=dic[i]
print(dic2)

{1: 100, 2: 90, 3: 5, 5: 67, 8: 3}

Declare a dictionary which is to be sorted
Declare an empty dictionary where sorted key value pairs are to be added
sorted(dic) has all the keys of dic in sorted order.It only has the keys and not keyvalue pairs. sorted(dic) will have [1,2,3,5,8]
For each key in sorted order, add the key and the corresponding value into dic2.
dic2 has all the key-value pairs in sorted order of keys

In this approach, the dictionary is sorted in ascending order of values.

Input:

{2:90, 1: 100, 8: 3, 5: 67, 3: 5}

Output:

{8:3, 3:5 ,5:67 , 2:90, 1:100}

As shown above, we can see the dictionary is sorted according to its values.

We use the sorted() and items() methods together to sort the dictionary by value.
The items() is used to retrieve the items or values of the dictionary.
The key=lambda x: x[1] is a sorting mechanism that uses a lambda function.
This gives us key value pairs ehich are then converted into a dictionary using dict().

dic={2:90, 1: 100, 8: 3, 5: 67, 3: 5}
dic2=dict(sorted(dic.items(),key= lambda x:x[1]))
print(dic2)

{8: 3, 3: 5, 5: 67, 2: 90, 1: 100}

Published on 11-Mar-2021 09:15:54