👀 Views: 37 💬 Answers: 1 📅 Created: 2025-06-05

python arrays list Python

I'm a bit lost with I'm collaborating on a project where Quick question that's been bugging me - I'm working on a personal project and I'm working on a Python project where I need to dynamically resize a nested list (2D array) to accommodate new data. I'm working with `IndexError: list assignment index out of range` when trying to assign values to indices that I expect to be valid. I initialized a 2D list with a specific size but when I try to append new rows or modify existing ones, the code fails. Here's a snippet of what I've tried: ```python # Initializing a 2D list with 3 rows and 4 columns array_2d = [[0 for _ in range(4)] for _ in range(3)] # Attempting to update the value in a specific row and column array_2d[2][3] = 5 # Works fine # Now, trying to add a new row new_row = [1, 2, 3] array_2d[3] = new_row # This line throws IndexError ``` What I want to achieve is to be able to add new rows to the existing `array_2d` without running into index issues. I thought Python lists could dynamically resize, but I seem to be misunderstanding how this works. I've seen examples where lists are appended, but I need to maintain a specific structure. How can I safely append new rows to my 2D array and avoid this `IndexError`? Am I missing something fundamental about list operations in Python? I'm working on a CLI tool that needs to handle this. This is part of a larger web app I'm building. I'd really appreciate any guidance on this. Am I approaching this the right way? The project is a web app built with Python. Thanks for your help in advance!