How to iterate over a 2D array in Python

A 2D array, also known as a matrix, is a collection of elements arranged in rows and columns. In Python, you can use nested loops to iterate over a 2D array, making it easy to access and manipulate individual elements. In this tutorial, we will guide you through the process of iterating over a 2D array with code examples.
Before you can iterate over a 2D array, you need to create one. You can use nested lists to represent a 2D array in Python. Here's an example of creating a simple 3x3 matrix:
There are two common approaches to iterate over a 2D array in Python: using nested loops and using list comprehensions. We'll cover both methods in this tutorial.
Nested loops are a straightforward way to iterate over a 2D array. The outer loop iterates over rows, and the inner loop iterates over columns. Here's how you can do it:
Output:
In this example, the outer loop iterates over each row, and the inner loop iterates over the elements in that row.
List comprehensions provide a more concise way to iterate over a 2D array and create a new list based on the elements. For example, if you want to create a flattened list from a 2D array:
Output:
In this example, the list comprehension iterates over the rows and elements in the 2D array, creating a flattened list.
You can modify the iteration process by adding conditional statements or performing specific operations on the elements during the iteration. For example, you can find specific elements, calculate the sum of rows or columns, or apply functions to each element in the 2D array.
Here's an example of finding the sum of each row in a 2D array:
Output:
You can customize the iteration to suit your specific needs.
In this tutorial, we have covered how to create and iterate over a 2D array in Python using nested loops and list comprehensions. These techniques are essential for working with matrices, images, and other grid-like data structures in Python.
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