How does Python’s list comprehension work?

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ICSM Computer · Answer

Python’s list comprehension is a concise way to create lists by applying an expression to each item in an iterable, optionally filtering elements with a condition—all in a single, readable line.
Basic Syntax
[expression for item in iterable if condition]
expression — what you want to produce for each item (can be just the item itself or a transformed version)item — a variable representing each element from the iterableiterable — any sequence or iterable (like a list, range, string, etc.)if condition — optional filter to include only items that satisfy the condition
Example 1: Square numbers from 0 to 4
squares = [x**2 for x in range(5)]
print(squares)  # Output: [0, 1, 4, 9, 16]
Example 2: Filter even numbers and double them
evens_doubled = [x * 2 for x in range(10) if x % 2 == 0]
print(evens_doubled)  # Output: [0, 4, 8, 12, 16]
How it works:
Iterates over each element in iterable.Applies the optional if condition to filter elements.Evaluates the expression for each filtered element.Collects all results into a new list.
Benefits
More concise and readable than using loops to build lists.Often faster than equivalent for loops in Python due to internal optimizations.

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How does Python’s list comprehension work?

ICSM Computer

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1 Answers

Basic Syntax

Example 1: Square numbers from 0 to 4

Example 2: Filter even numbers and double them

How it works:

Benefits

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