def test_crystal_structure_handling(self): sample = self._ws.sample() self.assertEquals(sample.hasCrystalStructure(), False) self.assertRaises(RuntimeError, sample.getCrystalStructure) cs = CrystalStructure('5.43 5.43 5.43', 'F d -3 m', 'Si 0 0 0 1.0 0.01') sample.setCrystalStructure(cs) self.assertEquals(sample.hasCrystalStructure(), True) cs_from_sample = sample.getCrystalStructure() self.assertEquals(cs.getSpaceGroup().getHMSymbol(), cs_from_sample.getSpaceGroup().getHMSymbol()) self.assertEquals(cs.getUnitCell().a(), cs_from_sample.getUnitCell().a()) self.assertEquals(len(cs.getScatterers()), len(cs_from_sample.getScatterers())) self.assertEquals(cs.getScatterers()[0], cs_from_sample.getScatterers()[0]) sample.clearCrystalStructure() self.assertEquals(sample.hasCrystalStructure(), False) self.assertRaises(RuntimeError, sample.getCrystalStructure)
def _update_distributions_and_weights(self): crystal_structure = CrystalStructure(str(self._unit_cell), str(self._space_group), str(self._atoms)) reflection_generator = ReflectionGenerator(crystal_structure) # Calculate all unique reflections within the specified resolution limits, including structure factors unique_hkls = reflection_generator.getUniqueHKLs(self.d_min, self.d_max) structure_factors = reflection_generator.getFsSquared(unique_hkls) # Calculate multiplicities of the reflections point_group = crystal_structure.getSpaceGroup().getPointGroup() multiplicities = [len(point_group.getEquivalents(hkl)) for hkl in unique_hkls] # Calculate weights as F^2 * multiplicity and normalize so that Sum(weights) = 1 weights = np.array([x * y for x, y in zip(structure_factors, multiplicities)]) self._parameter_lock.acquire() self._peak_weights = weights / sum(weights) d_values = reflection_generator.getDValues(unique_hkls) self._peak_distributions = [partial(np.random.normal, loc=d, scale=self._relative_sigma * d) for d in d_values] self._parameter_lock.release()
def test_SpaceGroup(self): structure = CrystalStructure("5.43 5.42 5.41", "F d -3 m", "Al 1/3 0.454 1/12 1.0 0.01") spaceGroup = structure.getSpaceGroup() self.assertEqual(spaceGroup.getHMSymbol(), "F d -3 m")