Wrong alat used if ibrav != 0

[giovannipizzi]

Here: https://github.com/aiidateam/qe-tools/blob/develop/qe_tools/parsers/qeinputparser.py#L1107

we are assuming that alat is np.linalg.norm(cell[0]). This is true only for ibrav = 0. For the other cases, we should use the value already stored above in alat.

Here is an example input file that gives the wrong result:

scf.in.txt

[giovannipizzi]

See #18 on how to run the example