def test_strain_mapping_affine_transform():
latt = diffpy.structure.lattice.Lattice(3, 3, 3, 90, 90, 90)
atom = diffpy.structure.atom.Atom(atype='Zn', xyz=[0, 0, 0], lattice=latt)
structure = diffpy.structure.Structure(atoms=[atom], lattice=latt)
ediff = DiffractionGenerator(300., 0.025)
affines = [[[1, 0, 0], [0, 1, 0], [0, 0, 1]],
[[1.04, 0, 0], [0, 1, 0], [0, 0, 1]],
[[1.08, 0, 0], [0, 1, 0], [0, 0, 1]],
[[1.12, 0, 0], [0, 1, 0], [0, 0, 1]]]
data = []
for affine in affines:
# same coords as used for latt above
latt_rot = diffpy.structure.lattice.Lattice(3, 3, 3, 90, 90, 90, baserot=affine)
structure.placeInLattice(latt_rot)
diff_dat = ediff.calculate_ed_data(structure, 2.5)
dpi = sim_as_signal(diff_dat, 64, 0.02, 2.5)
data.append(dpi.data)
data = np.array(data)
dp = ElectronDiffraction2D(data.reshape((2, 2, 64, 64)))
m = dp.create_model()
ref = ScalableReferencePattern(dp.inav[0, 0])
m.append(ref)
m.multifit()
disp_grad = ref.construct_displacement_gradient()
assert disp_grad.data.shape == np.asarray(affines).reshape(2, 2, 3, 3).shape
def test_function(diffraction_pattern):
ref = ScalableReferencePattern(diffraction_pattern)
x, y = _index_coords(diffraction_pattern.data)
func = ref.function(x=x, y=y)
np.testing.assert_almost_equal(func, diffraction_pattern.data)
def test_scalable_reference_pattern_init(diffraction_pattern):
ref = ScalableReferencePattern(diffraction_pattern)
assert isinstance(ref, ScalableReferencePattern)