Coverage for gpaw/test/lcao/test_bulk.py: 100%

1import numpy as np 

2from ase import Atoms 

3from gpaw import GPAW 

4import pytest 

5 

6 

7def test_lcao_bulk(in_tmp_dir): 

8 bulk = Atoms('Li', pbc=True) 

9 k = 4 

10 g = 8 

11 calc = GPAW(gpts=(g, g, g), kpts=(k, k, k), 

12 mode='lcao', basis='dzp') 

13 bulk.calc = calc 

14 e = [] 

15 niter = [] 

16 A = [2.6, 2.65, 2.7, 2.75, 2.8] 

17 for a in A: 

18 bulk.set_cell((a, a, a)) 

19 e.append(bulk.get_potential_energy()) 

20 niter.append(calc.get_number_of_iterations()) 

21 

22 a = np.roots(np.polyder(np.polyfit(A, e, 2), 1))[0] 

23 print('a =', a) 

24 assert a == pytest.approx(2.6378, abs=0.0003) 

25 

26 e_ref = [-1.8677343236247692, -1.8690343169380492, -1.8654175796625045, 

27 -1.8566274574918875, -1.8432374955346396] 

28 niter_ref = [6, 6, 6, 6, 6] 

29 

30 print(e) 

31 energy_tolerance = 0.0003 

32 niter_tolerance = 0 

33 

34 for i in range(len(A)): 

35 assert e[i] == pytest.approx(e_ref[i], abs=energy_tolerance) 

36 assert niter[i] == pytest.approx(niter_ref[i], abs=niter_tolerance) 

37 

38 wf1 = calc.get_pseudo_wave_function(kpt=3, band=0) 

39 calc.write('Li', mode='all') 

40 calc2 = GPAW('Li') 

41 # calc2.initialize_positions() 

42 wf2 = calc2.get_pseudo_wave_function(kpt=3, band=0) 

43 assert abs(wf1 - wf2).max() == pytest.approx(0, abs=1e-9)