def test_equality(self):
""" Test that __eq__ works as expected """
c1 = Crystal.from_database("Pu-alpha")
c2 = deepcopy(c1)
self.assertEqual(c1, c2)
c3 = Crystal.from_database("Pu-epsilon")
self.assertNotEqual(c1, c3)
def test_equality():
"""Test that __eq__ works as expected"""
c1 = Crystal.from_database("Pu-alpha")
c2 = deepcopy(c1)
assert c1 == c2
c3 = Crystal.from_database("Pu-epsilon")
assert c1 != c3
def test_powdersim_peak_alignment():
""" Test that the diffraction peaks align with what is expected. """
crystal = Crystal.from_database("C")
for reflection in [(0, 1, 1), (1, 2, 0), (-1, 2, 0)]:
qknown = np.linalg.norm(crystal.scattering_vector((0, 1, 1)))
# Range of scattering vectors is tightly centered around a particular reflection
# So that the maximum of the diffraction pattern MUST be at reflection (010)
q = np.linspace(qknown - 0.1, qknown + 0.1, 256)
pattern = powdersim(Crystal.from_database("C"), q)
assert abs(q[np.argmax(pattern)] - qknown) < q[1] - q[0]
def test_constructors(self):
""" Test Supercell constructors for varyous 'builtin' structures """
for name in islice(Crystal.builtins, 20):
with self.subTest(name):
s = Crystal.from_database(name).supercell(2, 2, 2)
self.assertEqual(len(s), 8 * len(s.crystal))
def get_pendulossung(name='Si', miller=[0, 0, 0], keV=200, opt='p'):
''' give the theorertical 2-beam approximation Pendullosung thickness
- `name` : compound
- `miller` : [h,k,l]
- `keV` : wavelength (keV)
RETURN
- xi : Pendullosung thickness (A)
'''
# compute structure factor
from crystals import Crystal
crys = Crystal.from_database(name)
lat_vec = crys.reciprocal_vectors
pattern = np.array(
[list(a.coords_fractional) + [a.atomic_number] for a in crys.atoms])
hkl, Fhkl = structure_factor3D(pattern,
lat_vec,
hklMax=max(miller),
sym=0,
v='')
ax, by, cz = crys.lattice_parameters[:3]
Vcell = crys.volume
# compute Pendullosung
h, k, l = miller
Ug, K = np.abs(Fhkl[h, k, l]) / Vcell, 1 / scatf.wavelength(keV)
xi = K / Ug
if 'p' in opt:
print(green + "\tPendullosung thickness " + name + '[%d%d%d]' %
(h, k, l) + black)
print('%-5s= %.2f\n%-5s= %.2f\n%-5s= %.2f' %
('K', K, 'Ug', Ug, 'xi', xi))
return xi
def test_return_shape():
""" Test that the return shape of pelectrostatic is the same as input arrays """
crystal = Crystal.from_database("C")
xx, yy = np.meshgrid(np.linspace(-10, 10, 32), np.linspace(-10, 10, 32))
potential = pelectrostatic(crystal, xx, yy)
assert xx.shape == potential.shape
def test_simulation_3_peaks(self):
"""
Test calibration from simulation, down to 1% error . Peaks (200) and (220) from monoclinic VO2 are used,
"""
s = np.linspace(0.11, 0.8, 1024)
q = 4 * np.pi * s
c = Crystal.from_database("vo2-m1")
I = powdersim(c, s)
peak1 = (2, 0, 0)
Gx1, Gy1, Gz1 = c.scattering_vector(peak1)
q1 = np.sqrt(Gx1 ** 2 + Gy1 ** 2 + Gz1 ** 2)
arr_index1 = np.argmin(np.abs(q - q1))
peak2 = (2, 2, 0)
Gx2, Gy2, Gz2 = c.scattering_vector(peak2)
q2 = np.sqrt(Gx2 ** 2 + Gy2 ** 2 + Gz2 ** 2)
arr_index2 = np.argmin(np.abs(q - q2))
peak3 = (3, 0, -2)
Gx2, Gy2, Gz2 = c.scattering_vector(peak3)
q3 = np.sqrt(Gx2 ** 2 + Gy2 ** 2 + Gz2 ** 2)
arr_index3 = np.argmin(np.abs(q - q3))
calibrated = powder_calq(
I,
c,
peak_indices=(arr_index1, arr_index2, arr_index3),
miller_indices=(peak1, peak2, peak3),
)
self.assertTupleEqual(I.shape, calibrated.shape)
self.assertTrue(np.allclose(q, calibrated, rtol=0.01))
def gen_xyz(file, n=[0, 0, 1], rep=[1, 1, 1], pad=0, xyz='', **kwargs):
''' convert cif file into autoslic .xyz input file
- file : cif_file
- rep : super cell repeat
- n : reorient of the z axis into n
- pad : amount of padding on each side (in unit of super cell size)
'''
if isinstance(file, str):
tail = ''.join(np.array(n, dtype=str)) + '.xyz'
if file.split('.')[-1] == 'cif':
crys = Crystal.from_cif(file)
if not xyz: xyz = file.replace('.cif', tail)
elif sum(np.array(list(Crystal.builtins)) == file):
crys = Crystal.from_database(file)
if not xyz: xyz = file + tail
lat_vec = np.array(crys.lattice_vectors)
lat_params = crys.lattice_parameters[:3]
pattern = np.array([[a.atomic_number] + list(a.coords_cartesian) +
[a.occupancy, 1.0] for a in crys.atoms])
else:
if not xyz: raise Exception('xyz filename required')
pattern = file
pattern, lat = make_xyz(xyz,
pattern,
lat_vec,
lat_params,
n=n,
pad=pad,
rep=rep,
**kwargs)
npy_file = xyz.replace('.xyz', '.npy')
np.save(npy_file, [lat, pattern])
print(colors.green + 'binary coords file saved :' + colors.yellow +
npy_file + colors.black)
def setUp(self):
self.crystal = Crystal.from_database("C")
self.reflections = list(combinations_with_replacement(range(-3, 4), 3))
self.intensities = [
np.abs(structure_factor(self.crystal, *reflection))**2
for reflection in self.reflections
]
def test_side_effects():
""" Test that mesh arrays are not written to in pelectrostatic """
crystal = Crystal.from_database("C")
xx, yy = np.meshgrid(np.linspace(-10, 10, 32), np.linspace(-10, 10, 32))
xx.setflags(write=False)
yy.setflags(write=False)
potential = pelectrostatic(crystal, xx, yy)
def Li_rots():
crys = Crystal.from_database('Li')
coords = np.array([a.coords_cartesian for a in crys.atoms])
# files = rcc.rotate_xyz(crys,Nrot=8,name='dat/Lithium/rots/',opt='p')
files = rcc.orient_crystal(coords,ez=[0,0,1],n_u=[0,,1])
for file in files[:4] : rcc.show_grid(file,title=file,equal=1)#,xyTicks=3.49,xylims=[0,100,0,100])
def test_reciprocal_symmetry_operations(name):
"""Test that the reciprocal symmetry operations output makes sense"""
identity = np.eye(4)
c = Crystal.from_database(name)
symops = c.reciprocal_symmetry_operations()
assert np.allclose(identity, symops[0])
def test_primitive_for_builtins(self):
""" Test that all built-in crystal have a primitive cell """
for name in Crystal.builtins:
with self.subTest(name):
c = Crystal.from_database(name)
prim = c.primitive(symprec=0.1)
self.assertLessEqual(len(prim), len(c))
def test_builtins(self):
""" Test that all names in Crystal.builtins build without errors,
and that Crystal.source is correctly recorded. """
for name in Crystal.builtins:
with self.subTest(name):
c = Crystal.from_database(name)
self.assertIn(name, c.source)
def import_crys(file):
if file.split('.')[-1] == 'cif':
crys = Crystal.from_cif(file)
elif sum(np.array(list(Crystal.builtins)) == file):
crys = Crystal.from_database(file)
else:
raise Exception('cannot import %s' % file)
return crys
def test_chemical_composition_add_to_unity(self):
""" Test that AtomicStructure.chemical_composition always adds up to 1 """
# Faster to create a large atomic structure from a Crystal object
# Testing for 10 crystal structures only
for name in islice(Crystal.builtins, 10):
with self.subTest("Chemical composition: " + name):
structure = AtomicStructure(atoms=Crystal.from_database(name))
self.assertAlmostEqual(sum(structure.chemical_composition.values()), 1)
def test_reciprocal_symmetry_operations(self):
""" Test that the reciprocal symmetry operations output makes sense """
identity = np.eye(4)
for name in Crystal.builtins:
with self.subTest(name):
c = Crystal.from_database(name)
symops = c.reciprocal_symmetry_operations()
self.assertTrue(np.allclose(identity, symops[0]))
def Li_xyz(path,n=[0,0,1],dopt=1,lfact=1.0,wobble=0,tail=''):
file = path+'Li%s%s.xyz' %(''.join(np.array(n,dtype=str)),tail)
crys = Crystal.from_database('Li')
pattern = np.array([
[a.atomic_number]+list(lfact*a.coords_cartesian)+[a.occupancy,wobble] for a in crys.atoms])
# lat_params = tuple(lfact*np.array(crys.lattice_parameters[:3]))
lat_params = lfact*np.array(crys.lattice_vectors)
coords,lat = rcc.make_xyz(file,pattern,lat_params,n,fmt='%.4f',dopt='s')
return file
def test_shape_and_dtype():
"""Test that output of structure_factor is same shape as input,
and that the dtype is complex"""
crystal = Crystal.from_database(next(iter(Crystal.builtins)))
h, k, l = np.meshgrid([1, 2, 3], [1, 2, 3], [1, 2, 3])
sf = structure_factor(crystal, h, k, l)
assert sf.shape == h.shape
assert sf.dtype == complex
def test_str_vs_repr(name):
"""Test that str and repr are workign as expected"""
c = Crystal.from_database(name)
# If small crystal, repr and str should be the same
if len(c) <= 10:
assert repr(c) == str(c)
else:
assert repr(c) != str(c)
def test_ase_atoms_back_and_forth(name):
""" Test conversion to and from ase Atoms """
crystal = Crystal.from_database(name)
to_ase = crystal.to_ase()
crystal2 = Crystal.from_ase(to_ase)
# ase has different handling of coordinates which can lead to
# rounding beyond 1e-3. Therefore, we cannot compare directly sets
# assertSetEqual(set(crystal), set(crystal2))
assert len(crystal) == len(crystal2)
def test_cif_writer_idempotence(name):
""" Test that conversion to CIF of a structure loaded from CIF is idempotent. """
# Testing on all built-in structure assures us that corner cases
# are taken care of.
cryst = Crystal.from_database(name)
with tempfile.TemporaryDirectory() as temp_dir:
f = Path(temp_dir) / "temp.cif"
cryst.to_cif(f)
cryst2 = Crystal.from_cif(f)
assert cryst == cryst2
def test_lattice_parameters_back_and_forth(name):
"""Test that the conversion between lattice vectors and lattice parameters
is working"""
c = Crystal.from_database(name)
lv1 = c.lattice_vectors
params = c.lattice_parameters
lv2 = lattice_vectors_from_parameters(*params)
assert np.allclose(lv1, lv2)
def test_output_shape(self):
""" Test that the output shape is as expected. """
# Simulate a powder pattern first
crystal = Crystal.from_database("vo2-m1")
q = np.linspace(0.2, 10, 1024)
I = powdersim(crystal=crystal, q=q)
radii = np.arange(0.1, 5, 1 / 50)
pairdist = patterson(q=q, I=I, crystal=crystal, radii=radii)
self.assertEqual(radii.shape, pairdist.shape)
def test_str_vs_repr(self):
""" Test that str and repr are workign as expected """
for name in Crystal.builtins:
with self.subTest(name):
c = Crystal.from_database(name)
# If small crystal, repr and str should be the same
if len(c) <= 10:
self.assertEqual(repr(c), str(c))
else:
self.assertNotEqual(repr(c), str(c))
def test_powder_calq(self):
""" Test scattering vector calibration """
crystal = Crystal.from_database("vo2-m1")
self.dataset.powder_calq(crystal, (10, 100), [(1, 0, 0), (2, 0, 0)])
# Check that shapes match
self.assertTupleEqual(self.dataset.powder_eq().shape,
self.dataset.scattering_vector.shape)
# Check that scattering_vector is strictly increasing
self.assertTrue(
np.all(np.greater(np.diff(self.dataset.scattering_vector), 0)))
def test_reciprocity_with_symmetry_expansion(self):
""" Test that symmetry_reduction is reciprocal to symmetry_expansion """
structures = ["vo2-m1", "Os", "Na"] # , 'Nb', 'Pd', 'Zn']
for s in structures:
with self.subTest("Crystal " + s):
cryst = Crystal.from_database(s)
asym_cell = symmetry_reduction(cryst.unitcell,
cryst.symmetry_operations())
ucell = set(
symmetry_expansion(asym_cell, cryst.symmetry_operations()))
self.assertEqual(set(cryst.unitcell), ucell)
def test_dirax_indexing_initial_guess(name):
"""
Test that indexing succeeds with an initial guess and very few reflections.
"""
cryst = Crystal.from_database(name)
# We restrict the number of reflections to a single (0,0,0); with
# the initial guess, indexing should still succeed!
lat, _ = index_dirax([(0, 0, 0)], initial=cryst)
assert np.allclose(lat.lattice_parameters,
cryst.lattice_parameters,
atol=1)
def test_equality(self):
""" Test that AtomicStructure is equal to itself but not others """
self.assertEqual(self.structure, self.structure)
self.assertEqual(self.structure, deepcopy(self.structure))
self.assertNotEqual(self.structure, self.substructure)
# Special case: make structures from Crystals
c1 = Crystal.from_database("vo2-m1")
c2 = deepcopy(c1)
s1 = AtomicStructure(atoms=c1)
s2 = AtomicStructure(atoms=c2.atoms)
self.assertEqual(s1, s2)
def test_dirax_indexing_ideal(name, bound):
"""
Test that indexing always succeeds with an ideal
set of reflections: no noise, no alien reflections.
"""
cryst = Crystal.from_database(name)
refls = [
cryst.scattering_vector(r)
for r in cryst.bounded_reflections(bound=bound)
]
lat, hkls = index_dirax(refls)
assert np.allclose(hkls - np.rint(hkls), 0, atol=0.001)