Problem with lpp on post processing

Submitted by Narendra Akiti on Thu, 06/12/2014 - 12:18

Hi All,

After completion of LIGGGHTS simulation, to see the results on paraview, i am trying to convert the output files into vtk format
in the post folder. But it is giving the following error.

naren@ubuntu:~/LIGGGHTS/LIGGGHTS-PUBLIC/examples/LIGGGHTS/Tutorials_public/chute_wear/post$ lpp dump*.chute
aborting due to errors: Invalid or no argument given for cpunum

It worked well till now, suddenly i come across this problem.

Please help...

Thanks,

aaigner's picture

aaigner | Thu, 06/12/2014 - 15:46

Hi,

you can try to run lpp with the option '--cpunum', for instance
lpp --cpunum 2 dump*.chute

If it doesn't work, contact us again.

Bests,
Andreas

Narendra Akiti | Fri, 06/13/2014 - 02:17

Thanks a lot. It's working with "lpp --cpunum 2 dump*.chute" command.
What do you mean by "--cpunum 2"?
Also, can you please tell which is the best software to draw the geometry and generate the mesh files?

Kind Regards,
Narendra

ting.hu@monash.edu | Sun, 07/05/2020 - 04:58

Hi Andreas,
I got the same problem and I run lpp --cpunum 2 dump*.chute, it's still the same error
Could you please help me out with this? Thank you
Regards
Ting

msandli | Fri, 06/13/2014 - 05:07

the --cpunum flag tells lpp how many cpu's to use - literally, cpu number. so, --cpunum 2 means use 2 cpu's on whatever hardware you're running lpp on. if it's a single desktop/laptop or a small simulation, --cpunum 2 is actually fairly reasonable. on the other hand, if you have access to super-computing (hpc) resources, --cpunum can be as many cpu's as you can request (devs, i'm assuming --cpunum should be equal to the number of nodes * number of CPU's per node in a shared HPC envrionment?).

as far as your second question, when are you drawing the geometry and mesh files? if you need to draw geometry before you import them into liggghts, anything that can generate an .stl file should work. I use Solidworks because that's what I have access to. If you mean during/after a simulation, liggghts can generate mesh files by using various dump commands

Narendra Akiti | Sat, 06/14/2014 - 03:05

Hi msandli,

Thanks a lot. I need to draw the geometry before import them into liggghts. I am trying to use gmsh for this.