Working with lists is a fundamental aspect of Python and data manipulation. One such manipulation skill is the ability to add elements to nested lists in Python. A nested list in Python refers to a list inside another list.

This tutorial will guide you through the process of adding elements to a nested list in Python, whether it’s at the beginning, at the end, or at a specific index in the nested list.

Creating a Nested List

Before we dive into adding elements, we need to know how to create a nested list. This can be done by simply declaring a list with other lists as its elements. Here’s an example:

Adding Elements to the Nested List

There are several methods to add elements to a nested list, such as using the built-in append() and insert() functions.

Use the append() Function

The append() function is used to add an element at the end of the list. Here is an example of how to use the append() function:

This will add the number 10 to the end of the last list in the nested list.

Use the insert() Function

Conversely, the insert() function lets you add elements at a specific index in the list. The function takes two parameters: the index, and the element. Here is an example:

This code adds the number 15 to the second position of the first list in the nested list.

Full Python Code

Output

[[1, 2, 3], [4, 5, 6], [7, 8, 9, 10]]
[[1, 15, 2, 3], [4, 5, 6], [7, 8, 9, 10]]

Conclusion

Adding elements to a nested list in Python can be accomplished using built-in list methods. The append() function allows you to add elements to the end of a list, while the insert() function gives you the flexibility to add elements at any index in the list. Utilizing these tools effectively can greatly enhance your data manipulation abilities in Python.