Develop test set and package it for conda-forge and bring it to python3

[jochym]

@farhi, @protik77 let us have the discussion on further development here.

[jochym]

Hi Pawel. I'm using QE-util only for its PWscf module so that ASE can basically compute phonons with it.

However, the ASE Phonon module is currently not very useful as it lacks plenty of stuff and is very slow (and I think it is also wrong in the way it stores the force constants).

So, these days I use QE-util together with PhonoPy, and the whole stuff within ASE. A kind of Russian puppet infrastructure, which takes the best of all packages for my peculiar use.

Having interacted with the ASE guys for some time, I think that QE-util should first be simplified so that it brings a minimalistic calculator. The gap for merge into ASE is then small. Afterwards, one can enrich the calculator with other capabilities that are today in QE-util.

Regarding the phonon code in ase I have a similar experience @farhi . Phonopy is much better.
I agree, it would be much better to have a proper calculator for ase. When I was writing qe-util it was too complicated for the time I had to complete the project - thus qe-util. But I think the file-io calculator of present ASE will be a good base class for QE calculator. The problem for me is still - I do not use QE at the moment so have no test cases and to little experience.

[harishpvv]

Sir, can you make it a full pledged wrapper for QE (including pp, dos, ph, matdyn, epw etc.,) compatible with python3 and ase. Though I've a little experiance with python, I can help you if possible and needed.

Thanks.