def test_apply_transformation(self):
trans = MagOrderingTransformation({"Fe": 5})
p = Poscar.from_file(os.path.join(test_dir, 'POSCAR.LiFePO4'),
check_for_POTCAR=False)
s = p.structure
alls = trans.apply_transformation(s, 10)
self.assertEqual(len(alls), 3)
f = SpacegroupAnalyzer(alls[0]["structure"], 0.1)
self.assertEqual(f.get_spacegroup_number(), 31)
model = IsingModel(5, 5)
trans = MagOrderingTransformation({"Fe": 5}, energy_model=model)
alls2 = trans.apply_transformation(s, 10)
#Ising model with +J penalizes similar neighbor magmom.
self.assertNotEqual(alls[0]["structure"], alls2[0]["structure"])
self.assertEqual(alls[0]["structure"], alls2[2]["structure"])
s = self.get_structure('Li2O')
#Li2O doesn't have magnetism of course, but this is to test the
# enumeration.
trans = MagOrderingTransformation({"Li+": 1}, max_cell_size=3)
alls = trans.apply_transformation(s, 100)
self.assertEqual(len(alls), 10)
def test_to_from_dict(self):
m = IsingModel(5, 4)
d = m.as_dict()
o = IsingModel.from_dict(d)
self.assertIsInstance(o, IsingModel)
self.assertAlmostEqual(o.j, 5)
idx = int(np.where(np.isclose(self.distances, dist))[0])
energy -= self.j[idx] * s1 * getattr(site.specie, "spin", 0)
return energy
#atoms = read_vasp('POSCAR2')
#write_vasp('POSCAR', sort(atoms), vasp5=True, direct=True, label=atoms.get_chemical_formula())
if __name__ == '__main__':
"""
J = [0.00240319, 0.00224361, 0.00146472, 0.00125072, 0.00122649]
model_uuu = MultiIsingModel(J, 5.0, Structure.from_file('2FEPOSCAR'), [3, 3])
model_uuu.recommended_j()
model_uud = MultiIsingModel(J, 5.0, Structure.from_file('2FEPOSCAR'), [3, -3])
uuu = model_uuu.get_energy()
uud = model_uud.get_energy()
print(uuu - uud)
"""
J = -0.03489
uu = Structure.from_file('2FEPOSCAR')
ud = uu.copy()
uu.add_spin_by_site([3.291, 3.291])
ud.add_spin_by_site([3.285, -3.285])
model = IsingModel(J, 5.0)
print(model.get_energy(uu) - model.get_energy(ud))
uuu = Structure.from_file('POSCAR3')
uud = uu.copy()
uuu.add_spin_by_site([3, 3, 3])
uud.add_spin_by_site([3, 3, -3])
model = IsingModel(J, 5.0)
print(model.get_energy(uuu) - model.get_energy(uud))
