Find Length of List in Python (3 Examples)
Hi! This tutorial will demonstrate how to determine the length of a list in the Python programming language.
Here is an overview:
Let’s dive into the Python code!
Create Example List
We will create an example Python list of strings whose length will be calculated in this tutorial. Therefore, in your preferred Python coding IDE, run the line of code below to create the example list of strings:
my_list = ["apple","orange","pear","banana","grape"] print(my_list) # ['apple', 'orange', 'pear', 'banana', 'grape'] print(type(my_list)) # <class 'list'>
Now that the example list has been created, we will look at examples of how to get its length.
Example 1: Get Length of List Using len() Function
In this first example, we will use Python’s len() function to find the length of the list:
list_length = len(my_list) print(list_length) # 5 print(type(list_length)) # <class 'int'>
len() function in the above example simply counts the number of elements in the list and returns it. Using this function is a very easy and quick way to get the length of a list in Python.
Example 2: Get Length of List Using List Comprehension & sum() Function
list_length = sum(1 for x in my_list) print(list_length) # 5 print(type(list_length)) # <class 'int'>
We used list comprehension inside the
sum() function to run an iteration through the elements in the list, which were then counted.
sum() function can only take integer values, we used 1 to represent the count of the elements inside the list.
Example 3: Get Length of List Using For Loop
In this last example, we will use a for loop to determine the length of the list:
list_length = 0 for i in my_list: list_length += 1 print(list_length) # 5 print(type(list_length)) # <class 'int'>
In the above example, the for loop iterates through all the elements inside the list and stops when it gets to the last element.
We used the
list_length variable, whose initial value is set to 0, to count the number of the items in the list by incrementing its value by one inside the for loop.
This means that with each iteration, the value of
list_length increases by 1. Note that in Python,
list_length += 1 is the same as
list_length = list_length + 1.
With these simple examples, we have demonstrated how to find the length of a list in Python. I do hope you found this tutorial helpful!
Video, Further Resources & Summary
Do you need more explanations on how to find the length of a list in Python? Then you should have a look at the following YouTube video of the Statistics Globe YouTube channel.
In the video, we explain in some more detail how to find the length of a list in Python.
The YouTube video will be added soon.
Furthermore, I encourage you to check out other interesting Python list tutorials on Statistics Globe, starting with these ones:
- Transpose 2D List in Python (3 Examples)
- Append 2D List in Python (3 Examples)
- Learn Python Programming
- count() Method for Lists in Python (2 Examples)
- Convert List of Tuples to List of Lists in Python (3 Examples)
This post has shown how to find the length of a list in Python. In case you have further questions, you may leave a comment below.
This page was created in collaboration with Ifeanyi Idiaye. You might check out Ifeanyi’s personal author page to read more about his academic background and the other articles he has written for the Statistics Globe website.
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