👀 Views: 28 💬 Answers: 1 📅 Created: 2025-06-10

numpy unique strings sorting Python

I can't seem to get I'm working on a personal project and I'm working with an scenario with `np.unique` when trying to get unique values from a custom string array. My input array contains a mix of strings with varying cases and some strings that are numerical but still in string format. I expected `np.unique` to handle these correctly and return them sorted in a case-insensitive manner, but it doesn't seem to behave as I anticipated. Here’s a snippet of what I’m working with: ```python import numpy as np my_array = np.array(['apple', 'Banana', 'cherry', 'banana', 'Apple', 'cherry', '123', '456', '123']) unique_values = np.unique(my_array) print(unique_values) ``` When I run this code, it returns: ``` ['123' '456' 'Banana' 'Apple' 'apple' 'banana' 'cherry'] ``` I expected the output to be sorted in a case-insensitive manner, resulting in: ``` ['123' '456' 'apple' 'Banana' 'cherry'] ``` I’ve tried using the `return_inverse` argument as well as converting the strings to a common case before using `np.unique`, but I still get the same sorted output based on ASCII values. Is there a built-in way in NumPy to achieve case-insensitive unique sorting, or do I need to implement a custom solution? Any help would be greatly appreciated! For context: I'm using Python on macOS. Is there a better approach?