Apply Function to All Elements in List in Python

To apply a function to a list in Python, the easiest way is to use list comprehension to apply a function to each element in a list.

def add_one(x):
    return x + 1

example_list = [0, 1, 2, 3, 4, 5]

print([add_one(i) for i in example_list])

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

You can also use the map() function.

def add_one(x):
    return x + 1

example_list = [0, 1, 2, 3, 4, 5]

print(list(map(add_one, example_list)))

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

When working with collections of data in Python, the ability to easily manipulate and change these collections can be very valuable.

One example of this might be if you have a function you want to apply to each of the elements of a list.

We can easily apply a function to all elements in a list.

The easiest way is with list comprehension.

Below is an example of how to use list comprehension to apply a function to a list.

def add_one(x):
    return x + 1

example_list = [0, 1, 2, 3, 4, 5]

print([add_one(i) for i in example_list])

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

Using map() to Apply a Function to a List in Python

The Python map() function is very useful and allows us to apply a function to a list.

To use map(), we just need to pass a function and a list to map, and then convert the returned value back to a list.

Below is a simple example of using map() to apply a function to a list of integers in Python.

def add_one(x):
    return x + 1

example_list = [0, 1, 2, 3, 4, 5]

print(list(map(add_one, example_list)))

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

Using a Lambda Expression inside map() to Apply a Function to a List in Python

The map() function can take both regular functions and lambda functions. Let’s do the same operation as above but instead let’s use a lambda expression in map().

Below shows you how you can use a lambda function in map() to apply a function to a list in your Python code.

example_list = [0, 1, 2, 3, 4, 5]

print(list(map(lambda x: x+1, example_list)))

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

Hopefully this article has been useful for you to learn how to apply functions to lists in your Python code.