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np.concatenate raises ValueError on joining arrays with incompatible shapes in NumPy 1.24

๐Ÿ‘€ Views: 35 ๐Ÿ’ฌ Answers: 1 ๐Ÿ“… Created: 2025-06-16
numpy arrays concatenation Python

I'm working on a personal project and I'm relatively new to this, so bear with me. I'm trying to use `np.concatenate` to join two NumPy arrays along a specific axis, but I'm running into a `ValueError`. I'm attempting to concatenate arrays of shapes (3, 4) and (2, 4) along axis 0, which I expected to work since they have compatible dimensions in the other axis. Hereโ€™s the code Iโ€™m using: ```python import numpy as np a = np.random.rand(3, 4) b = np.random.rand(2, 4) result = np.concatenate((a, b), axis=0) ``` When I run this, I get the following behavior: ``` ValueError: all the input arrays must have the same number of dimensions ``` Iโ€™ve checked the shapes of the arrays, and they seem correct. I also tried reshaping the arrays to (3, 4) and (2, 4) explicitly before concatenation but still faced the same scenario. Iโ€™m unsure why Iโ€™m receiving this behavior, as the shapes seem compatible for concatenation. Can someone guide to understand whatโ€™s going wrong here? Are there any additional considerations I should be aware of when using `np.concatenate`? Thanks! What am I doing wrong? I'm working on a API that needs to handle this. What am I doing wrong? I'm on Ubuntu 22.04 using the latest version of Python. Thanks, I really appreciate it!