[MRG] Replaced coo_matrix with coo_array better compatability and added tes… by nathanneike · Pull Request #782

[MRG] Replaced coo_matrix with coo_array better compatability and added tes… by nathanneike · Pull Request #782 · PythonOT/POT

Types of changes

Bug fix (non-breaking change which fixes an issue)
Improvement (non-breaking change which improves the codebase)

Motivation and context / Related issue

Modernizes the POT backend by migrating from the deprecated scipy.sparse.coo_matrix to the modern scipy.sparse.coo_array API. This ensures future compatibility as SciPy moves away from matrix-based sparse classes in favor of array-based ones.

How has this been tested (if it applies)

Updated NumPy backend coo_matrix() method to return coo_array instead of coo_matrix
Updated sparse_coo_data() to handle both coo_array and coo_matrix for backward compatibility
Added test case verifying coo_array element-wise multiplication functionality
All 2972 tests pass successfully

PR checklist

I have read the CONTRIBUTING document.
The documentation is up-to-date with the changes I made (check build artifacts).
All tests passed, and additional code has been covered with new tests.
I have added the PR and Issue fix to the RELEASES.md file.