[Python] Counting the frequency of elements in a list using a dictionary

Question

I want to count the frequency of all elements in a list using a dictionary. How can I do it?

Answer 1

You need to create a dictionary with each element of the list as keys and their frequency as values. Then you can find the frequency of any element by accessing its value.

Here is an example:

>>> aa=[1, 2, 3, 2, 1, 3, 1, 2, 3, 3]
>>> freq={}
>>> for v in aa:
...     freq[v]=freq.get(v,0)+1
...
>>> freq
{1: 3, 2: 3, 3: 4}

Now you can find the frequency of any element using the dictionary 'freq'.