How do you count values in a list python?

In this tutorial, we will learn about the Python List count[] method with the help of examples.

The count[] method returns the number of times the specified element appears in the list.

Example

# create a list
numbers = [2, 3, 5, 2, 11, 2, 7]

# check the count of 2
count = numbers.count[2]


print['Count of 2:', count]

# Output: Count of 2: 3

Syntax of List count[]

The syntax of the count[] method is:

list.count[element]

count[] Parameters

The count[] method takes a single argument:

element - the element to be counted

Return value from count[]

The count[] method returns the number of times element appears in the list.

Example 1: Use of count[]

# vowels list
vowels = ['a', 'e', 'i', 'o', 'i', 'u']

# count element 'i'
count = vowels.count['i']


# print count
print['The count of i is:', count]

# count element 'p'
count = vowels.count['p']


# print count
print['The count of p is:', count]

Output

The count of i is: 2
The count of p is: 0

Example 2: Count Tuple and List Elements Inside List

# random list
random = ['a', ['a', 'b'], ['a', 'b'], [3, 4]]

# count element ['a', 'b']
count = random.count[['a', 'b']]


# print count
print["The count of ['a', 'b'] is:", count]

# count element [3, 4]
count = random.count[[3, 4]]


# print count
print["The count of [3, 4] is:", count]

Output

The count of ['a', 'b'] is: 2
The count of [3, 4] is: 1

The count[] is a built-in function in Python. It will return the total count of a given element in a list. The count[] function is used to count elements on a list as well as a string.

In this Python tutorial, you will learn:

Python count
Python List count[]
Example 1: List Count
Example 2: Find the count of elements [Duplicates] in a givenlist

Python List count[]

The count[] is a built-in function in Python. It will return you the count of a given element in the list.

Syntax:

list.count[element]

Parameters:

element: The element you want to find the count.

ReturnValue:

The count[] method will return an integer value, i.e., the count of the given element from the given list. It returns a 0 if the value is not found in the given list.

Example 1: List Count

Following example shows the working of count[] function on a list:

list1 = ['red', 'green', 'blue', 'orange', 'green', 'gray', 'green']
color_count = list1.count['green']
print['The count of color: green is ', color_count]

Output:

The count of color: green is  3

Example 2: Find the count of elements [Duplicates] in a givenlist

list1 = [2,3,4,3,10,3,5,6,3]
elm_count = list1.count[3]
print['The count of element: 3 is ', elm_count]

Output:

The count of element: 3 is  4

Summary:

The count[] is a built-in function in Python. It will return you the count of a given element in a list or a string.
In the case of a list, the element to be counted needs to be given to the count[] function, and it will return the count of the element.
The count[] method returns an integer value.

Below are the three solutions:

Fastest is using a for loop and storing it in a Dict.

import time
from collections import Counter


def countElement[a]:
    g = {}
    for i in a:
        if i in g: 
            g[i] +=1
        else: 
            g[i] =1
    return g


z = [1,1,1,1,2,2,2,2,3,3,4,5,5,234,23,3,12,3,123,12,31,23,13,2,4,23,42,42,34,234,23,42,34,23,423,42,34,23,423,4,234,23,42,34,23,4,23,423,4,23,4]


#Solution 1 - Faster
st = time.monotonic[]
for i in range[1000000]:
    b = countElement[z]
et = time.monotonic[]
print[b]
print['Simple for loop and storing it in dict - Duration: {}'.format[et - st]]

#Solution 2 - Fast
st = time.monotonic[]
for i in range[1000000]:
    a = Counter[z]
et = time.monotonic[]
print [a]
print['Using collections.Counter - Duration: {}'.format[et - st]]

#Solution 3 - Slow
st = time.monotonic[]
for i in range[1000000]:
    g = dict[[[i, z.count[i]] for i in set[z]]]
et = time.monotonic[]
print[g]
print['Using list comprehension - Duration: {}'.format[et - st]]

Result

#Solution 1 - Faster

{1: 4, 2: 5, 3: 4, 4: 6, 5: 2, 234: 3, 23: 10, 12: 2, 123: 1, 31: 1, 13: 1, 42: 5, 34: 4, 423: 3}
Simple for loop and storing it in dict - Duration: 12.032000000000153

#Solution 2 - Fast

Counter[{23: 10, 4: 6, 2: 5, 42: 5, 1: 4, 3: 4, 34: 4, 234: 3, 423: 3, 5: 2, 12: 2, 123: 1, 31: 1, 13: 1}]
Using collections.Counter - Duration: 15.889999999999418

#Solution 3 - Slow

{1: 4, 2: 5, 3: 4, 4: 6, 5: 2, 34: 4, 423: 3, 234: 3, 42: 5, 12: 2, 13: 1, 23: 10, 123: 1, 31: 1}
Using list comprehension - Duration: 33.0

Is there a count function for lists in Python?

Python List count[] method returns the count of how many times a given object occurs in a List.

How do you count occurrences in a list?

Using the count[] Function The "standard" way [no external libraries] to get the count of word occurrences in a list is by using the list object's count[] function. The count[] method is a built-in function that takes an element as its only argument and returns the number of times that element appears in the list.

What does count [] do in Python?

Count[] is a Python built-in function that returns the number of times an object appears in a list. The count[] method is one of Python's built-in functions. It returns the number of times a given value occurs in a string or a list, as the name implies.

How do I count multiple values in a list Python?

If you want to count multiple items in a list, you can call count[] in a loop. This approach, however, requires a separate pass over the list for every count[] call; which can be catastrophic for performance. Use couter[] method from class collections , instead.