Get the averaged total of the volumetric data a certain axis direction.
        For example, useful for visualizing Hartree Potentials from a LOCPOT
        file.

        Args:
            ind (int): Index of axis.

        Returns:
            Average total along axis

def get_average_along_axis(self, ind):
        """
        Get the averaged total of the volumetric data a certain axis direction.
        For example, useful for visualizing Hartree Potentials from a LOCPOT
        file.

        Args:
            ind (int): Index of axis.

        Returns:
            Average total along axis
        """
        m = self.data["total"]
        ng = self.dim
        if ind == 0:
            total = np.sum(np.sum(m, axis=1), 1)
        elif ind == 1:
            total = np.sum(np.sum(m, axis=0), 1)
        else:
            total = np.sum(np.sum(m, axis=0), 0)
        return total / ng[(ind + 1) % 3] / ng[(ind + 2) % 3]