Well, I also like the way the tasks are distributed, it is conceptually very clear. I know a different code that saves a DOS file after a band calculation and the newbies come to me with strange peaks in DOS that are caused by a flat band along a line. Calling dos from pw.x or pw from dos.x masks that conceptual clarity. However, we have to be practical and run the frequent calculations as easily as possible. I would prepend a nscf calculation with "standard options" , and give warning in the otput file that non-standard options can be done doing the nscf calculation separately.
Also, I would alway make pw.x to write the self-consistent DOS in a file after an scf calculation, no matter how coarse is the k-points grid. I find this useful for checking purposes (e.g. to know if an impurity have levels in the gaps). Also, for simple metals the k-points grid needed to have converged energies and forces also is enough to have a good DOS. Then let the user the choice to do post processing if want a DOS with an occupation scheme different than the SCF. I would put this file in the .save directory and name it prefix.scfdos or something like that. Boris, thank for your script. I will soon test it. Maybe it can be embedded in PWGUI. Best regards Eduardo ---------- Mensaje reenviado ---------- > From: Paolo Giannozzi <giannozz at democritos.it> > To: PWSCF Forum <pw_forum at pwscf.org> > Date: Thu, 26 Feb 2009 10:34:30 +0100 > Subject: Re: [Pw_forum] band and dos input files in xcrysden > > On Feb 21, 2009, at 17:05 , Eduardo Ariel Menendez Proupin wrote: > > Let me remind how is the process to obtain the DOS. It has three >> calculations >> and 3 input files >> >> pw.x < si.scf.in > si.scf.out # self consistent >> pw.x <si.dos.in > si.dos.out # non selfconsistent dense k-points mesh >> and a few options >> dos.x <si.dos2.in > si.dos2.out # postprocessing >> > > Hi Eduardo, the issue you raise is a serious one and requires some though. > Right now several standard calculations in q-e are clumsy because they > require separate steps. While I think that it is a good idea to keep > separate > steps separate, I also think that at least the most common calculations > might > be streamlined. I am not convinced that the PWGui is the right tool for > this, > though, at least not in the present form (a tool to produce input data). > The ideal solution would be the usage of a high-level scripting language > like > python to "glue" the various pieces together, but this is highly nontrivial > (at least for me and for 99% of q-e users). > A simpler option could be to collapse some calculations into the same > executable: > for instance > - add a call to dos after a nscf calculation in pw.x, > add a call to bands after a bands calculation in pw.x > or > - prepend a nscf calculation to dos.x, > prepend a band calculation to bands.x > Suggestions are welcome > > Paolo > --- > Paolo Giannozzi, Democritos and University of Udine, Italy > > > > > -------------- next part -------------- An HTML attachment was scrubbed... URL: http://www.democritos.it/pipermail/pw_forum/attachments/20090305/e9b64e3d/attachment-0001.htm