1def test_cfg():
2    import numpy as np
3
4    from ase.build import molecule
5    from ase.io import read, write
6
7    a = molecule('CO2')
8    f = np.array([[1, 2, 3], [4, 5, 6], [7, 8, 9]])
9    a.set_array('test', f)
10
11    write('test.cfg', a)
12
13    b = read('test.cfg')
14    assert np.all(b.get_array('test') == f)
15
16    a.set_momenta(2 * f)
17    write('test.cfg', a)
18
19    b = read('test.cfg')
20    assert np.all(np.abs(a.get_momenta() - b.get_momenta()) < 1e-3)
21