.. todo:: docstring for get_data

def get_data(self, datatype, mode, disp):
        """ .. todo:: docstring for get_data
        """

        # Imports
        import os
        from ..const import EnumDispDirection as _E_DD
        from ..const import EnumAnharmRepoData
        from ..error import RepoError as RErr

        # Must be valid mode
        if not (mode >=0 and isinstance(mode, int)):
            raise ValueError("Mode must be a non-negative integer")
        ## end if

        # Must be a valid disp direction
        if not disp in _E_DD:
            raise ValueError("'{0}' is not a valid " +
                    "displacement enum value".format(disp))
        ## end if

        # Must be a valid data type
        if not datatype in EnumAnharmRepoData:
            raise ValueError("'{0}' is not a valid " +
                    "repository data type enum value".format(datatype))
        ## end if

        # Get the appropriate geom group name
        if disp == _E_DD.NO_DISP:
            grpname = self.G_geom_ref
        else:
            grpname = self.F_mode_fmt % \
                                    (mode, self.dircode[disp])
        ## end if

        # Get the group, complaining if repo not bound
        try:
            grp = self._repo.get(grpname)
        except AttributeError:
            raise RErr(RErr.STATUS,
                        "Cannot load; no repository open", "")
        ## end try

        # If succeeded, check if group not found
        if grp is None:
            raise RErr(RErr.GROUP,
                    "Group '" + grpname + "' not found",
                    self.fname)
        ## end if

        # Group found, try loading the data object; complain if not found
        try:
            out_data = grp.get(datatype).value
        except AttributeError:
            raise RErr(RErr.DATA,
                    "Dataset '" + datatype + "' not found",
                    self.fname)
        ## end try

        # Return as-is (h5py creates NumPy arrays of appropriate dimensions)
        return out_data