visualize forces and velocities in Paraview

Submitted by carlesbp on Sat, 04/05/2014 - 21:30

Hi everyone!

This may be a simple question and probably I am missing something obvious but, after converting the files to vtk using the pizza tool, I am able to visualise the simulation with no problem, but I cannot find the way of seeing the forces, velocities or different radius in the particles. I try to insert the Glyph to try some suggestions that I have seen in the forum, but I am just able to select atom type.
What can I do? do I have to transform the files in pizza to another format? I am dumping all velocities and forces!

Thanks!!!

Forums:

carlesbp | Mon, 04/07/2014 - 14:58

I am not 100% sure, but I think I have to convert the files with pizza after doing the regular convertion to vtk format, specifying the characteristis of the atom that I want to convert, for example:

t = d.time()
return vector of selected timestep values
fx,fy,... = d.atom(100,"fx","fy",...)
return vector(s) for atom ID N
fx,fy,... = d.vecs(1000,"fx","fy",...) return vector(s) for timestep N
atom() returns vectors with one value for each selected timestep
vecs() returns vectors with one value for each selected atom in the timestep

this is from the pizza.py documentation. Am I looking at the right place? any instructions on how to operate with these commands?

Thanks again!!

Daniel Queteschiner | Tue, 04/08/2014 - 09:52

It should be sufficient to post-process your dump files (typically generated via the dump custom command) using the lpp tool. After importing, ParaView should then allow you to select any dumped atom properties from the combo box next to the color bar/range settings.

carlesbp | Tue, 04/08/2014 - 12:05

Hi Daniel!! thanks for your answer!! I see what you mean, but I think my problem is that I can only show atom type. I am missing something to be able to show the velocities and forces option in Paraview.
When you say using the dump custom command, how do you use it? because I am using that one.
I hope you can help me!

carlesbp | Fri, 04/11/2014 - 20:57

Hi Daniel thanks for your answer! I think that my version of pizza was not the right one, I have downloaded the one from the github link you provided but I am facing the same problem. When I am in the post folder and i call pizza with python i type:

d=dump("dump*.xxx")
and then
v=vtk(d) to transform to vtk file
v.many() to write the files.

Which is the command that I have to use in LPP to get the file that paraview can open? I have been trying after d=dump with the tselect.all and aselect.all commands and then d.write() but it only writes one file!

Cheers

Daniel Queteschiner | Sun, 04/13/2014 - 18:27

You don't need all that stuff.
On the console just go to the folder containing your dump* files and type:

python $HOME/path/to/lpp/src/lpp.py dump*

You may want to set up an alias in your .bashrc file for that, e.g.

alias lpp="python $HOME/path/to/lpp/src/lpp.py"

and than just use

lpp dump*

on the console.

carlesbp | Tue, 04/15/2014 - 11:25

Hi Daniel finally I got the results and all the visualization wanted. As you said, I was doing a different process...
Thank you so much!!! I was getting a bit desperated about it!!
Manhy thanks
Carles