[Wien] basic questions

[Gavin Abo]

See below for my comments.

> I am running my job on remote server with 2 nodes with multi cores.
> scf was conversed successfully.
>
> I have few basic questions:
>
> 1. Is it possible to run all further calculation on a single PC/laptop 
> using previous server files? I think no.

The answer should be "maybe".  It depends on number of different things 
like:

a) what the further calculations are
b) what the calculation setup was
c) what software/hardware is used

For example, you might be able to transfer files from a calculation 
where the parallel setup used four processors on the server and it might 
run fine a PC with four processors.  If the PC only had two processors, 
there would not be enough processors for it to work. Some calculations 
might need the binary files produced by WIEN2k. If the server and PC 
software/hardware is similar enough, the binary files might work.  Say 
the server is using a 64 bit Linux but the PC is using a 32 bit Linux, 
then the 64 bit binary file will not work on the 32 bit system.  Servers 
typically have better hardware (larger disk storage and RAM).  On the 
server, GB/TB sized calculation files could be easily generated, whereas 
the PC might only be able to handle MB/GB calculation files.

> (For example, I want to run x lapw2 -fermi -p/x optic -p/ x joint -p/ 
> x karam -p on local PC and I want  single case.scf, case.energy and 
> case.mat_* files ti run on my local PC.

For that, it should be better to do those calculations on the server, 
then copy any output files that you need over to your local PC.

There are some parallel files that can be combined.  Search the mailing 
list archive or Internet, I think examples were given that used the 
'cat' command.  For energy files, there is the gather_energy.pl script 
in the BoltzTraP package [ 
http://www.icams.de/content/departments/cmat/boltztrap/ , 
http://www.mail-archive.com/wien%40zeus.theochem.tuwien.ac.at/msg13418.html 
].  Another script that combines vector files is described in the WIEN2k 
usersguide (section "9.15 join_vectorfiles") [ 
http://www.wien2k.at/reg_user/textbooks/usersguide.pdf ].

> 2. how to generated case.klist_band file on terminal (for each core)?
>     I do it as: take files from server to local PC and then generate 
> it using xcrysden and then load all files on server again.

You should just need a copy of the case.struct file on your local PC for 
that.  Open the case directory with case.struct in XCrySDen (File->Open 
WIEN2k->Select k-path), select the k-path, and save the file as 
case.klist_band.  After that, copy it from the local PC to the case 
directory on the server.  You shouldn't need one for each core or node, 
I believe the WIEN2k scripts take care of that or it is handled by the 
common NFS file system.

> 3. After run_lapw I always submit a separate job for each command 
> after finishing previous one. Is there any way so that I can write all 
> steps for a particular job (i.e. for band or DOSs of Optical 
> properties) and submit the job? or I have to submit a separate job for 
> each command as I am doing now?

Yes, you should be able to do multiple steps using one job.  Just 
program your job file to do it.  Since some files that you might need 
could be overwritten between steps, you will have to use save_lapw or a 
command like cp/mv in your job file to backup the needed files between 
steps.