Sort list by frequency in python

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How do I sort a list by its frequency in Python?

For example, I have the list:

[1,2,3,4,3,3,3,6,7,1,1,9,3,2]
 

The above list would be sorted in the order of the frequency of its values to create the following list, where the item with the greatest frequency is placed at the front:

[3,3,3,3,3,1,1,1,2,2,4,6,7,9]
May 13, 2019 in Python by ana1504.k
• 7,910 points
4,245 views

1 answer to this question.

0 votes
You can try the following for a collections.Counter:

counts = collections.Counter(lst)
new_list = sorted(lst, key=lambda x: -counts[x])
 

Alternatively, you could write the second line without a lambda:

counts = collections.Counter(lst)
new_list = sorted(lst, key=counts.get, reverse=True)
answered May 13, 2019 by SDeb
• 13,300 points

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