Nested list comprehension in Python

List comprehensions are a concise and powerful feature in Python that allows you to create lists in a single line of code. Nested list comprehensions take this concept further by allowing you to create lists of lists in a compact and readable way. In this tutorial, we'll explore the syntax and usage of nested list comprehensions with code examples.
Before diving into nested list comprehensions, let's briefly review the basic syntax of a list comprehension.
Nested list comprehensions allow you to create lists of lists in a concise manner. The syntax for a nested list comprehension is as follows:
Here, the outer comprehension iterates over the outer iterable, and for each item in the outer iterable, the inner comprehension iterates over the inner iterable. The expression_inner is evaluated for each combination of items from the outer and inner iterables.
Let's use nested list comprehensions to transpose a matrix. Transposing a matrix involves switching its rows and columns.
In this example, the outer comprehension (for i in range(len(matrix[0]))) iterates over the columns of the original matrix, and the inner comprehension ([row[i] for row in matrix]) collects the elements from the corresponding column. The result is a transposed matrix.
Nested list comprehensions provide a concise and readable way to create lists of lists in Python. Understanding the syntax and practicing with examples will help you leverage this feature effectively in your code.
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