Coverage for gpaw/test/pw/test_si_stress_libvdwxc.py: 45%

1import numpy as np 

2import pytest 

3from ase.build import bulk 

4from ase.calculators.fd import calculate_numerical_stress 

5 

6from gpaw.utilities import compiled_with_libvdwxc 

7from gpaw import GPAW, PW, Mixer 

8from gpaw.mpi import world 

9from gpaw.test import gen 

10from gpaw.xc.libvdwxc import vdw_df, libvdwxc_has_spin, libvdwxc_has_stress 

11 

12 

13skip_reason = "libvdwxc version does not implement stress" 

14if compiled_with_libvdwxc(): 

15 try: 

16 skip_cond = not libvdwxc_has_stress() 

17 except SystemError: 

18 skip_cond = True 

19else: 

20 skip_cond = True 

21 

22 

23def _check_libvdwxc_stress(in_tmp_dir, gpaw_new, xc, setups, s_ref): 

24 assert libvdwxc_has_spin() and libvdwxc_has_stress() 

25 si = bulk('Si') 

26 si.calc = GPAW(mode=PW(200), 

27 mixer=Mixer(0.7, 5, 50.0), 

28 xc=xc, 

29 kpts=(1, 1, 2), # Run (1, 1, 2) to avoid gamma pt code 

30 convergence={'energy': 1e-8}, 

31 parallel={'domain': min(2, world.size)}, 

32 setups=setups, 

33 txt='si_stress.txt') 

34 

35 si.set_cell(np.dot(si.cell, 

36 [[1.02, 0, 0.03], 

37 [0, 0.99, -0.02], 

38 [0.2, -0.01, 1.03]]), 

39 scale_atoms=True) 

40 

41 si.get_potential_energy() 

42 

43 if not gpaw_new: 

44 # Trigger nasty bug (fixed in !486): 

45 si.calc.wfs.pt.blocksize = si.calc.wfs.pd.maxmyng - 1 

46 

47 s_analytical = si.get_stress() 

48 if s_ref is None: 

49 s_ref = calculate_numerical_stress(si, 1e-5) 

50 print("REF", s_ref) 

51 print(s_analytical) 

52 s_err = s_analytical - s_ref 

53 assert np.all(abs(s_err) < 1e-4) 

54 

55 

56@pytest.mark.stress 

57@pytest.mark.skipif(skip_cond, reason=skip_reason) 

58def test_pw_si_stress_libvdwxc_gga(in_tmp_dir, gpaw_new): 

59 s_ref = [-0.17538969, -0.08992427, -0.14401403, 

60 -0.05984851, -0.00058295, 0.04351124] 

61 xc = vdw_df() 

62 _check_libvdwxc_stress(in_tmp_dir, gpaw_new, xc, "paw", s_ref) 

63 

64 

65@pytest.mark.stress 

66@pytest.mark.skipif(skip_cond, reason=skip_reason) 

67def test_pw_si_stress_libvdwxc_mgga(in_tmp_dir, gpaw_new): 

68 setups = {'Si': gen('Si', xcname='PBEsol')} 

69 s_ref = [-0.13724147, -0.05995537, -0.11039066, 

70 -0.05893786, 0.01830188, 0.04031258] 

71 xc = {'name': 'mBEEF-vdW', 'backend': 'libvdwxc'} 

72 _check_libvdwxc_stress(in_tmp_dir, gpaw_new, xc, setups, s_ref)