def test_bandsexport_single_kp(self):
"""
Plot band for single k-point (issue #2462).
"""
kpnts = KpointsData()
kpnts.set_kpoints([[0., 0., 0.]])
bands = BandsData()
bands.set_kpointsdata(kpnts)
bands.set_bands([[1.0, 2.0]])
bands.store()
# matplotlib
options = [str(bands.id), '--format', 'mpl_singlefile']
res = self.cli_runner.invoke(cmd_bands.bands_export,
options,
catch_exceptions=False)
self.assertIn(
b'p.scatter', res.stdout_bytes,
'The string p.scatter was not found in the bands mpl export')
# gnuplot
with self.cli_runner.isolated_filesystem():
options = [str(bands.id), '--format', 'gnuplot', '-o', 'bands.gnu']
self.cli_runner.invoke(cmd_bands.bands_export,
options,
catch_exceptions=False)
with open('bands.gnu', 'r') as gnu_file:
res = gnu_file.read()
self.assertIn(
'vectors nohead', res,
'The string "vectors nohead" was not found in the gnuplot script'
)
def test_spin_unpolarized():
"""Test the function for a non spin-polarized calculation meaning there will be a single spin channel."""
from aiida.orm import BandsData
occupations = numpy.array([
[2., 2., 2., 2., 0.],
[2., 2., 2., 2., 0.],
[2., 2., 2., 2., 0.],
[2., 2., 2., 2., 0.],
])
bands = BandsData()
bands.set_array('occupations', occupations)
bands.store()
h**o = get_highest_occupied_band(bands)
assert h**o == 4
def test_spin_polarized(self, fixture_database):
"""Test the function for a spin-polarized calculation meaning there will be two spin channels."""
from aiida.orm import BandsData
occupations = numpy.array([
[
[2., 2., 2., 2., 0.],
[2., 2., 2., 2., 0.],
],
[
[2., 2., 2., 2., 0.],
[2., 2., 2., 2., 0.],
]
])
bands = BandsData()
bands.set_array('occupations', occupations)
bands.store()
h**o = get_highest_occupied_band(bands)
assert h**o == 4
def test_threshold(self, fixture_database):
"""Test the `threshold` parameter."""
from aiida.orm import BandsData
threshold = 0.002
bands = BandsData()
bands.set_array('occupations', numpy.array([[2., 2., 2., 2., 0.001, 0.0015]]))
bands.store()
# All bands above the LUMO (occupation of 0.001) are below `2 * threshold`
h**o = get_highest_occupied_band(bands, threshold=threshold)
assert h**o == 4
bands = BandsData()
bands.set_array('occupations', numpy.array([[2., 2., 2., 2., 0.001, 0.003]]))
bands.store()
# A band above the LUMO (occupation of 0.001) has an occupation above `2 * threshold`
with pytest.raises(ValueError):
get_highest_occupied_band(bands, threshold=threshold)
def create_structure_bands():
"""Create bands structure object."""
alat = 4. # angstrom
cell = [
[
alat,
0.,
0.,
],
[
0.,
alat,
0.,
],
[
0.,
0.,
alat,
],
]
strct = StructureData(cell=cell)
strct.append_atom(position=(0., 0., 0.), symbols='Fe')
strct.append_atom(position=(alat / 2., alat / 2., alat / 2.),
symbols='O')
strct.store()
@calcfunction
def connect_structure_bands(strct): # pylint: disable=unused-argument
alat = 4.
cell = np.array([
[alat, 0., 0.],
[0., alat, 0.],
[0., 0., alat],
])
kpnts = KpointsData()
kpnts.set_cell(cell)
kpnts.set_kpoints([[0., 0., 0.], [0.1, 0.1, 0.1]])
bands = BandsData()
bands.set_kpointsdata(kpnts)
bands.set_bands([[1.0, 2.0], [3.0, 4.0]])
return bands
bands = connect_structure_bands(strct)
bands_isolated = BandsData()
bands_isolated.store()
# Create 2 groups and add the data to one of them
g_ne = Group(label='non_empty_group')
g_ne.store()
g_ne.add_nodes(bands)
g_ne.add_nodes(bands_isolated)
g_e = Group(label='empty_group')
g_e.store()
return {
DummyVerdiDataListable.NODE_ID_STR: bands.id,
DummyVerdiDataListable.NON_EMPTY_GROUP_ID_STR: g_ne.id,
DummyVerdiDataListable.EMPTY_GROUP_ID_STR: g_e.id
}