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np.vstack gives ValueError when stacking arrays of different shapes in NumPy 1.24.3

๐Ÿ‘€ Views: 32 ๐Ÿ’ฌ Answers: 1 ๐Ÿ“… Created: 2025-06-23
numpy vstack array concatenation python

I'm updating my dependencies and I've hit a wall trying to I just started working with I'm working with a `ValueError` when trying to stack multiple arrays vertically using `np.vstack`. The behavior message I receive is: `ValueError: all the input array dimensions for the concatenation axis must match exactly`. I have checked the shapes of the arrays I'm trying to stack, and they are indeed different, but I expected `np.vstack` to automatically pad them with zeros or something similar. Hereโ€™s a minimal example of what Iโ€™m trying to do: ```python import numpy as np a = np.array([[1, 2], [3, 4]]) # shape (2, 2) b = np.array([5, 6, 7]) # shape (3,) # Attempting to stack these arrays result = np.vstack((a, b)) ``` When I run this code, I get the aforementioned `ValueError`. I need to combine these arrays into a single 2D array for further processing, but I'm not sure how to handle the mismatch in their shapes. Whatโ€™s the best way to achieve this? Should I be reshaping or padding them first? Any insights on how to stack arrays of different shapes without running into this scenario would be greatly appreciated! How would you solve this? I've been using Python for about a year now. I recently upgraded to Python LTS. I'd really appreciate any guidance on this.