In this tutorial, we will go through several methods to convert a Nested list to flat list using `Python`.

Lists are probably the most used data type in Python. Lists being mutable offer a lot of flexibility to perform a number of operations on the items of the list.

A list contains items separated by commas and enclosed within square brackets [ ].Â  Lists in `Python` can also have items of different `data types` together in a single list. A nested list is nothing but a list containing several lists for exampleÂ `[1,2,[3],[4,[5,6]]`

Often we need to convert these `nested lists to flat list` to perform regular list operations on the data. Fortunately, in Python, there are many ways to achieve this.

#### Convert Nested List To Flat List In Python

Output: `[1, 2, 3, 4, 5, 6]`

#### Flatten List using Inbuilt reduce Function

##### Method 1:

Output: `[14, 215, 383, 87, 298, 374, 2, 3, 4, 5, 6, 7]`

##### Method 2:

Output: `[14, 215, 383, 87, 298, 374, 2, 3, 4, 5, 6, 7]`

##### Method 3:

This is one of the most efficient ways to flatten a large list.

Output: `[14, 215, 383, 87, 298, 374, 2, 3, 4, 5, 6, 7]`

#### Flatten List Using List Compression

Output: `[14, 215, 383, 87, 298, 374, 2, 3, 4, 5, 6, 7]`

#### Flatten List Using NumPy

Note that, NumPy doesnâ€™t come bundled with Python Installation you have to install it which can be done simply using Pip Installer.

Once the installation is done you can run the code below,

Output: `[14, 215, 383, 87, 298, 374, 2, 3, 4, 5, 6, 7]`

The article was published on October 11, 2020 @ 1:42 PM