def from_band_structure(
cls,
band_structure: BandStructure,
energy_cutoff=defaults["energy_cutoff"],
symprec=defaults["symprec"],
):
kpoints = np.array([k.frac_coords for k in band_structure.kpoints])
efermi = band_structure.efermi
structure = band_structure.structure
full_kpoints, _, _, _, _, ir_to_full_idx = expand_kpoints(
structure,
kpoints,
symprec=symprec,
return_mapping=True,
time_reversal=True)
ibands = get_ibands(energy_cutoff, band_structure)
vb_idx = get_vb_idx(energy_cutoff, band_structure)
energies = {s: e[ibands[s]] for s, e in band_structure.bands.items()}
energies = {s: e[:, ir_to_full_idx] for s, e in energies.items()}
projections = {
s: p[ibands[s]]
for s, p in band_structure.projections.items()
}
band_centers = get_band_centers(full_kpoints, energies, vb_idx, efermi)
rotation_mask = get_rotation_mask(projections)
full_projections = {}
for spin, spin_projections in projections.items():
nbands = spin_projections.shape[0]
nkpoints = len(full_kpoints)
spin_projections = spin_projections[:, ir_to_full_idx].reshape(
(nbands, nkpoints, -1), order="F")
spin_projections /= np.linalg.norm(spin_projections, axis=2)[...,
None]
spin_projections[np.isnan(spin_projections)] = 0
full_projections[spin] = spin_projections
return cls.from_data(
full_kpoints,
full_projections,
rotation_mask=rotation_mask,
band_centers=band_centers,
)
def from_coefficients(
cls, coefficients, gpoints, kpoints, structure, symprec=defaults["symprec"]
):
logger.info("Initializing wavefunction overlap calculator")
mesh_dim = get_mesh_from_kpoint_numbers(kpoints)
if np.product(mesh_dim) == len(kpoints):
return cls(kpoints, coefficients, gpoints)
full_kpoints, *symmetry_mapping = expand_kpoints(
structure, kpoints, time_reversal=True, return_mapping=True, symprec=symprec
)
coefficients = desymmetrize_coefficients(
coefficients, gpoints, kpoints, structure, *symmetry_mapping
)
return cls(full_kpoints, coefficients, gpoints)
def test_expand_kpoints(symmetry_structure, shift, mesh):
def _kpoints_to_first_bz(kp):
"""helper function to map k-points to 1st BZ"""
kp = np.array(kp)
kp = kp - np.round(kp)
kp[kp.round(8) == -0.5] = 0.5
return kp
def _sort_kpoints(kp):
"""Helper function to put k-points in a consistent order"""
kp = kp.round(8)
sort_idx = np.lexsort((kp[:, 2], kp[:, 1], kp[:, 0]))
return kp[sort_idx]
# generate true k-points and IR k-points using spglib
atoms = AseAtomsAdaptor.get_atoms(symmetry_structure)
mapping, addresses = get_ir_reciprocal_mesh(mesh, atoms, is_shift=shift)
true_kpoints = addresses / mesh + shift / (mesh * 2)
true_kpoints = _kpoints_to_first_bz(true_kpoints)
true_kpoints_sort = _sort_kpoints(true_kpoints)
ir_mapping = np.unique(mapping, return_index=False)
ir_kpoints = true_kpoints[ir_mapping]
# try to expand the irreducible k-points back to the full BZ
full_kpoints, rots, _, _, op_mapping, kp_mapping = expand_kpoints(
symmetry_structure, ir_kpoints, return_mapping=True
)
full_kpoints = _kpoints_to_first_bz(full_kpoints)
full_kpoints_sort = _sort_kpoints(full_kpoints)
# assert final k-points match the expected true k-points
diff = np.linalg.norm(full_kpoints_sort - true_kpoints_sort, axis=1)
assert np.max(diff) == 0
# now ensure that the rotation mapping actually works
rotated_kpoints = []
for r, k in zip(op_mapping, kp_mapping):
rotated_kpoints.append(np.dot(rots[r], ir_kpoints[k]))
rotated_kpoints = _kpoints_to_first_bz(rotated_kpoints)
rotated_kpoints_sort = _sort_kpoints(rotated_kpoints)
# assert rotated k-points match the expected true k-points
diff = np.linalg.norm(rotated_kpoints_sort - true_kpoints_sort, axis=1)
assert np.max(diff) == 0
def from_deformation_potentials(cls,
deformation_potentials,
kpoints,
structure,
symprec=defaults["symprec"]):
logger.info("Initializing deformation potential interpolator")
mesh_dim = get_mesh_from_kpoint_numbers(kpoints)
if np.product(mesh_dim) == len(kpoints):
return cls.from_data(kpoints, deformation_potentials)
full_kpoints, rotations, _, _, op_mapping, kp_mapping = expand_kpoints(
structure,
kpoints,
time_reversal=True,
return_mapping=True,
symprec=symprec)
logger.warning(
"Desymmetrizing deformation potentials, this could go wrong.")
deformation_potentials = desymmetrize_deformation_potentials(
deformation_potentials, structure, rotations, op_mapping,
kp_mapping)
return cls.from_data(full_kpoints, deformation_potentials)