Flattening a list of lists is a common task in Python, often encountered when dealing with nested data structures. Here, we’ll explore some widely-used methods to flatten a list of lists, employing both simple and effective techniques.

How To Flatten A List Of Lists In Python?

Below, are the methods for How To Flatten A List Of Lists In Python.

• Using Nested Loops
• Using List Comprehension
• Using itertools.chain()
• Using functools.reduce()

Using Nested Loops

In this example, below code initializes a nested list and flattens it using nested loops, iterating through each sublist and item to create a flattened list. The result is then printed using print("Flattened List:", flattened_list).

Flattened List: [1, 2, 3, 4, 5, 6, 7, 8, 9]

Using List Comprehension

In this example, below code starts with a nested list and uses list comprehension to flatten it into a single list. The result, a flattened list, is displayed using `print(“Flattened List:”, flattened_list)`.

Flattened List: [1, 2, 3, 4, 5, 6, 7, 8, 9]

Using itertools.chain()

The itertools.chain() function is another efficient method for flattening. The chain() function takes multiple iterables and flattens them into a single iterable.

Flattened List: [1, 2, 3, 4, 5, 6, 7, 8, 9]

Using functools.reduce()

Using functools.reduce() with the operator concat function is another option. reduce() applies concat successively to the elements of the list, achieving flattening.

Flattened List: [1, 2, 3, 4, 5, 6, 7, 8, 9]