Introduction:

In Python, lists are a form of sequential data. This mutable array-like data structure makes it simple to store a group of objects. Finding a list’s length, or the number of elements it contains, is frequently important when working with lists in Python. It can be useful to know this information when checking input data or when looping through the list to do computations based on list size. If you looking to understand the central tendency of data or summarize large data into single-value do find Average of List in Python.

Len(), a built-in function in Python, thankfully makes it simple to determine a list’s length. The total number of entries in a list, often known as the list length, can be determined using various techniques in Python. This article demonstrates three different approaches to determining the list length in Python.

Python Code to Determine List Length

A list’s length in Python can be found in several different methods, and the task is straightforward. You can determine a list’s length using one of three approaches, depending on the task at hand:

  • Using programming logic without the use of functions.
  • Use an integrated function (recommended).
  • Importing a third-party library function.

The sections that follow provide examples of each of the three approaches.

Practice 1: Simple Counter Technique

Using a for loop and a counter is the first method of calculating the length of a list in Python. There are no imported or built-in functions needed for this approach.

The for loop and a counter is used to determine the list length in the following piece of code:

my_list = [0,1,2,3,4]
counter = 0
for element in my_list:
counter += 1
print(counter)

loop counter to determine list length

The number increases by one each time the loop traverses a list element. The list length is the counter’s ultimate value

Practice 2:

Len(), a built-in method in Python, can be used to determine a list’s length. The simplest and most used approach for calculating list length is this one.

Give the list as input to the len() method to use it. For instance:

my_list = [0,1,2,3,4]
print(len(my_list))

len() function to find list of length

Practice 3:

A function named length_hint() in the Python operator library can be used to determine the length of iterable objects. For lists and objects with known lengths, the function returns the actual length. As an alternative, it offers the approximate length.

Import the operator library method and supply the list as input to use the length_hint() function. For instance:

from operator import length_hint
my_list = [0,1,2,3,4]
print(length_hint(my_list))

operator list length_hint terminal output

Final Thoughts on How to Find the List Length in Python

It is typically advised to utilize the built-in len() function to determine the length of a list because of its dependability, simplicity, and performance. Alternative approaches, however, are always a good idea to be aware of because they could be useful in particular circumstances.

In Python programming, figuring out a list’s length is a fundamental operation, and the len() function offers a quick and effective way to do so. In this article, we looked at the len() function’s application and highlighted its importance in a number of programming contexts.