def _get_stddevs(self, C, stddev_types, num_sites):
        """
        Return standard deviations as defined in tables below
        """
        assert all(stddev_type in self.DEFINED_FOR_STANDARD_DEVIATION_TYPES
            for stddev_type in stddev_types)
        stddevs = [np.zeros(num_sites) + C['SigmaTot'] for _ in stddev_types]
        return stddevs
Return standard deviations as defined in tables below