Today, we’re revealing a Python superpower:** list comprehensions! **These are clever techniques to make lists that are both succinct and efficient. List comprehension in Python is a single line of code that allows you to construct lists from other lists or iterables. This allows you to perform operations on each item in a list quickly and efficiently. Python’s approach of condensing a for loop, a condition, and an output expression into a single line. The following is the basic structure of list comprehension:
new_list = [expression for item in old_list if condition]
In this structure:- expression is the operation performed on the item.
itemrefers to each item in the old list.conditionis optional, and filters the items that satisfy a certain condition. Let’s take an example:
squares = [number**2 for number in range(1, 11)]
print(squares) # Outputs: [1, 4, 9, 16, 25, 36, 49, 64, 81, 100]
In this example, we used a list comprehension to create a list of the squares of the numbers from** 1 to 10**.
Exercise
Now, it’s time for you to flex your Python muscles! Write a list comprehension that performs the following tasks:- Takes the list **numbers = [1, 2, 3, 4, 5, 6, 7, 8, 9, 10]**.
- Returns a new list containing only the even numbers from the “numbers” list.
Conclusion
And just like that, you’ve learned how to use list comprehensions in Python! This Pythonic feature not only simplifies but also speeds up your code. Continue to practice and explore different expressions and conditions. Are you ready to continue your Python journey? Pythonistas, march on!