def _get_kpoints(kpoint_mesh: Union[float, int, List[int]],
structure: Structure,
symprec: float = 0.01,
return_full_kpoints: bool = False
) -> Tuple[np.ndarray, ...]:
"""Gets the symmetry inequivalent k-points from a k-point mesh.
Follows the same process as SpacegroupAnalyzer.get_ir_reciprocal_mesh
but is faster and allows returning of the full k-point mesh and mapping.
Args:
kpoint_mesh: The k-point mesh as a 1x3 array. E.g.,``[6, 6, 6]``.
Alternatively, if a single value is provided this will be
treated as a reciprocal density and the k-point mesh dimensions
generated automatically.
structure: A structure.
symprec: Symmetry tolerance used when determining the symmetry
inequivalent k-points on which to interpolate.
return_full_kpoints: Whether to return the full list of k-points
covering the entire Brillouin zone and the indices of
inequivalent k-points.
Returns:
The irreducible k-points and their weights as tuple, formatted as::
(ir_kpoints, weights)
If return_full_kpoints, the data will be returned as::
(ir_kpoints, weights, full_kpoints, ir_kpoints_idx, ir_to_full_idx)
Where ``ir_kpoints_idx`` is the index of the unique irreducible k-points
in ``full_kpoints``. ``ir_to_full_idx`` is a list of indices that can be
used to construct the full Brillouin zone from the ir_mesh. Note the
ir -> full conversion will only work with calculated scalar properties
such as energy (not vector properties such as velocity).
"""
if isinstance(kpoint_mesh, (int, float)):
# TODO: Update this to use reciprocal length as in kgrid
kpoint_mesh = Kpoints.automatic_density_by_vol(structure, kpoint_mesh)
atoms = AseAtomsAdaptor().get_atoms(structure)
if not symprec:
symprec = 0.1
mapping, grid = spglib.get_ir_reciprocal_mesh(
kpoint_mesh, atoms, symprec=symprec)
full_kpoints = grid / kpoint_mesh
ir_kpoints_idx, ir_to_full_idx, weights = np.unique(
mapping, return_inverse=True, return_counts=True)
ir_kpoints = full_kpoints[ir_kpoints_idx]
if return_full_kpoints:
return ir_kpoints, weights, full_kpoints, ir_kpoints_idx, ir_to_full_idx
else:
return ir_kpoints, weights
