def test_get_feature_names_out(): """Check get_feature_names_out uses class name as prefix.""" est = LinearDiscriminantAnalysis().fit(X, y) names_out = est.get_feature_names_out() class_name_lower = "LinearDiscriminantAnalysis".lower() expected_names_out = np.array( [ f"{class_name_lower}{i}" for i in range(est.explained_variance_ratio_.shape[0]) ], dtype=object, ) assert_array_equal(names_out, expected_names_out)