Function get_checker_board

tests/recommender_base_test.py:20–28

Returns a 'checkerboard' matrix: where every even userid has liked every even itemid and every odd userid has liked every odd itemid. The diagonal is withheld for testing recommend methods

(X)

def get_checker_board(X):
    """Returns a 'checkerboard' matrix: where every even userid has liked
    every even itemid and every odd userid has liked every odd itemid.
    The diagonal is withheld for testing recommend methods"""
    ret = np.zeros((X, X))
    for i in range(X):
        for j in range(i % 2, X, 2):
            ret[i, j] = 1.0
    return csr_matrix(ret - np.eye(X))


class RecommenderBaseTestMixin: