test_neighbors.py 文件源码

def test_k_and_radius_neighbors_train_is_not_query():
    # Test kneighbors et.al when query is not training data

    for algorithm in ALGORITHMS:

        nn = neighbors.NearestNeighbors(n_neighbors=1, algorithm=algorithm)

        X = [[0], [1]]
        nn.fit(X)
        test_data = [[2], [1]]

        # Test neighbors.
        dist, ind = nn.kneighbors(test_data)
        assert_array_equal(dist, [[1], [0]])
        assert_array_equal(ind, [[1], [1]])
        dist, ind = nn.radius_neighbors([[2], [1]], radius=1.5)
        check_object_arrays(dist, [[1], [1, 0]])
        check_object_arrays(ind, [[1], [0, 1]])

        # Test the graph variants.
        assert_array_equal(
            nn.kneighbors_graph(test_data).A, [[0., 1.], [0., 1.]])
        assert_array_equal(
            nn.kneighbors_graph([[2], [1]], mode='distance').A,
            np.array([[0., 1.], [0., 0.]]))
        rng = nn.radius_neighbors_graph([[2], [1]], radius=1.5)
        assert_array_equal(rng.A, [[0, 1], [1, 1]])