[gpaw-users] trajectory file

[Ask Hjorth Larsen]

Hi Daniel Torres

On Tue, 2 Mar 2010, Daniel Torres wrote:

> Hi guys!
> Im using the following Py file. I notice that the trajectory file generated 
> is empty. Is this normal?
(...)

> bulk.set_calculator(calc)
> traj = PickleTrajectory('cell.traj', 'w', bulk)
> relax = QuasiNewton(bulk)
> relax.run(fmax=0.01)
> energy = bulk.get_potential_energy()

You need to do QuasiNewton(..., trajectory=traj, ...) for anything to be 
written to the trajectory file.  In other words, yes, this is normal :)

(It would technically be possible for the PickleTrajectory constructor to 
'attach itself' to the atoms object and automatically write whenever the 
atoms object changes, and I guess you expected that to happen, but that's 
not the way they work.)

Best regards
Ask