Coverage for gpaw/test/vdw/test_libvdwxc_mbeef.py: 100%

1import pytest 

2from gpaw.utilities import compiled_with_libvdwxc 

3 

4from ase.build import bulk 

5 

6from gpaw import GPAW, Davidson, Mixer, PW 

7from gpaw.xc.libvdwxc import vdw_mbeef 

8 

9from gpaw.test import gen 

10 

11pytestmark = pytest.mark.skipif(not compiled_with_libvdwxc(), 

12 reason='not compiled_with_libvdwxc()') 

13 

14 

15@pytest.mark.old_gpaw_only 

16@pytest.mark.mgga 

17def test_vdw_libvdwxc_mbeef(): 

18 setup = gen('Si', xcname='PBEsol') 

19 

20 system = bulk('Si') 

21 calc = GPAW(mode=PW(200), xc=vdw_mbeef(), 

22 kpts=(2, 2, 2), 

23 nbands=4, 

24 convergence=dict(density=1e-6), 

25 mixer=Mixer(1.0), 

26 eigensolver=Davidson(4), 

27 setups={'Si': setup}) 

28 system.calc = calc 

29 e = system.get_potential_energy() 

30 ref = -60.53662105617721 

31 err = abs(e - ref) 

32 print('e=%r ref=%r err=%r' % (e, ref, err)) 

33 # It would be reasonable to put 1e-6 as tolerance, 

34 # but the value changes by 4e-4 depending on libxc version. 

35 # See https://gitlab.com/gpaw/gpaw/issues/161 . 

36 assert err < 1e-3, err