ASE vs MDTraj vs nothing

[OndrejMarsalek]

It would be nice if ILI could work with an MDTraj trajectory, rather than ASE atoms. For processing trajectories, constructing ASE atoms for each frame seems wasteful. I don't mind atoms as an alternative if you think it's useful. Possibly even better - we could again separate specific "formats" of input from just feeding individual arguments to the constructor.

[OndrejMarsalek]

In any case, not really a priority, but I'd like to come back to it at some point.

[fuulish]

AFAICT, you need not construct individual atoms objects for each snapshot in a trajectory. It should work by just updating the positions. However, I agree that working on and MDTraj object would have some advantages.
Let's keep the issue open, so that we don't forget and can come back to it, later

[OndrejMarsalek]

Fair, that should work, though ASE atoms are still relatively heavyweight. It would be best if both are supported, eventually.