frequency of items in list python code example

Example 1: list count frequency python

import collections
a = [1,1,1,1,2,2,2,2,3,3,4,5,5]
counter=collections.Counter(a)
print(counter)
# Counter({1: 4, 2: 4, 3: 2, 5: 2, 4: 1})
print(counter.values())
# [4, 4, 2, 1, 2]
print(counter.keys())
# [1, 2, 3, 4, 5]
print(counter.most_common(3))
# [(1, 4), (2, 4), (3, 2)]

Example 2: freq count in python

freq = {} 
    for item in my_list: 
        if (item in freq): 
            freq[item] += 1
        else: 
            freq[item] = 1

Example 3: find frequency of numbers in list python

from collections import Counter

def frequency_table(n):
    table = Counter(n)
    print('Number\tFrequency')
    for number in table.most_common() :
        print('{0}\t{1}'.format(number[0], number[1]))
        
# src : Doing Math With Python