Python List Comprehensions

List comprehensions provide a concise way to create lists in Python. They allow you to combine and transform elements from existing lists into a new list.

Let’s consider an example where we have a list called numbers:

1	numbers = [1, 2, 3, 4, 5]

We can use a list comprehension to create a new list called numbers_power_2, which contains the elements of numbers raised to the power of 2:

1 2	numbers_power_2 = [n ** 2 for n in numbers] # [1, 4, 9, 16, 25]

Compared to using traditional loops or the map() function, list comprehensions offer a more readable and concise syntax, especially when the operation can be written on a single line.

Here’s an example of how the same transformation could be done using a loop:

1
2
3

numbers_power_2 = []
for n in numbers:
    numbers_power_2.append(n ** 2)

And using the map() function along with a lambda function:

1	numbers_power_2 = list(map(lambda n: n ** 2, numbers))

List comprehensions can simplify your code and make it more intuitive and expressive. They are often a preferred choice when dealing with list transformations.

tags: [“Python”, “List Comprehensions”, “Looping”, “Transforming Lists”]