Count the digits in a Numpy array

Question

How do you Count The Number Of Times Each Value Appears In An Array Of
Integers?
[0, 5, 4, 0, 4, 4, 3, 0, 0, 5, 2, 1, 1, 9]
Answer should be array([4, 2, 1, 1, 3, 2, 0, 0, 0, 1]) which means 0 comes 4 times,
1 comes 2 times, 2 comes 1 time, 3 comes 1 time and so on.python

Answer 1

Hey, @Sourav,

We can solve this with the collection module, which refers to count frequencies of all elements in the array link. 

import collections #Function to count frequency of each element it returns a dictionary data structure whose keys are array elements and values are their corresponding frequencies {0: 4,  1: 2,  2: 1,  3: 1]

def CountFrequency(arr):

    return collections.Counter(arr)  

if __name__ == "__main__": #Driver Function

 arr = [0, 5, 4, 0, 4, 4, 3, 0, 0, 5, 2, 1, 1, 9]

    freq = CountFrequency(arr)

for key, value in freq.iteritems():

        print key, " -> ", value

Output:

0-> 4

1->2

2->1

3->1

Hope this will help you.

Comments

Thanks Gitika,

It Works.