def test_type(self):
        rset = event.ResultSet()
        with pytest.raises(NotImplementedError):
            rset.extend([])
        with pytest.raises(NotImplementedError):
            rset.extend(False)
def __get_stop_condition(self):
        for covariance in self.__variances:
            if numpy.linalg.norm(covariance) == 0.0:
                return True