List comprehension is a concise and efficient way to create lists in Python. It allows you to iterate over an existing sequence (such as a list) and apply an expression to each item in a single line.

Syntax

new_list = [expression for element in old_list if condition]

• expression → Operation to perform on each element.
• element → Represents each item in old_list.
• old_list → The original list used for iteration.
• condition (optional) → Filters elements before applying expression.

Example 1: Creating a List of Squares

Using a for loop:

squares = []
for x in range(1, 11):
    squares.append(x**2)

Using list comprehension:

squares = [x**2 for x in range(1, 11)]
print(squares)  
# Output: [1, 4, 9, 16, 25, 36, 49, 64, 81, 100]

List comprehension reduces code complexity while maintaining readability.

Example 2: Selecting Even Numbers

Using a for loop:

numbers = [1, 2, 3, 4, 5, 6, 7, 8, 9, 10]
even_numbers = []
for number in numbers:
    if number % 2 == 0:
        even_numbers.append(number)

Using list comprehension:

even_numbers = [number for number in numbers if number % 2 == 0]
print(even_numbers)  
# Output: [2, 4, 6, 8, 10]

Why Use List Comprehension?

✔ More readable than traditional loops.
✔ Faster execution as it leverages Python’s optimized list operations.
✔ Less code without losing clarity.

Use it whenever you need to generate lists concisely while maintaining readability! 🚀

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