Coverage for gpaw/test/pw/test_si_stress.py: 100%

1import numpy as np 

2import pytest 

3from ase.build import bulk 

4 

5from gpaw import GPAW, PW, Mixer 

6from gpaw.mpi import world 

7 

8 

9@pytest.mark.stress 

10def test_pw_si_stress(in_tmp_dir, gpaw_new): 

11 xc = 'PBE' 

12 si = bulk('Si') 

13 si.calc = GPAW(mode=PW(200), 

14 mixer=Mixer(0.7, 5, 50.0), 

15 xc=xc, 

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

17 convergence={'energy': 1e-8}, 

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

19 txt='si_stress.txt') 

20 

21 si.set_cell(np.dot(si.cell, 

22 [[1.02, 0, 0.03], 

23 [0, 0.99, -0.02], 

24 [0.2, -0.01, 1.03]]), 

25 scale_atoms=True) 

26 

27 si.get_potential_energy() 

28 

29 if not gpaw_new: 

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

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

32 

33 s_analytical = si.get_stress() 

34 s_ref = [-0.16569446, -0.07630128, -0.1266625, 

35 -0.06144752, -0.02055657, 0.04574812] 

36 # si.calc.calculate_numerical_stress(si, 1e-5) 

37 print(s_analytical) 

38 s_err = s_analytical - s_ref 

39 assert np.all(abs(s_err) < 1e-4)