[lammps-users] Dump the position of a wall with wiggle movement

Dear Sirs,

I'm running some cases of granular dynamics regarding segregation with
vibration. I would like to know if there is a way to save in each time
step the position of a wall that moves with the wall/gran wiggle fix.
If not directly possible, how can be done ? I mean, I do not have yet
good knowledge of how it's structured Lammps, so if possible, could you
point me where can I add/change the code so this information can be
saved along with the atom data ?

Thanks in advance, best regards from,

Diego Peinado Martín.
Intrame S.A.

Since the position of the wall is given by an analytic
formula as a function of time (see the fix wall/gran doc
page), why do you need to save/print it? If you wanted
you could duplicate the formula with the variable command,
and print it out with thermo output, but you already know
the answer for what it's going to be.


2009/11/2 Diego Peinado Martín <[email protected]>:

Thanks for your early reply. Well, of course you are right. The reason
for trying to have this value with the data files is for doing some
automatic postprocessing. Sometimes there is an initial run without
shaking for having the particles packed and at rest. Also I modified the
code for the wall/gran fix to include an initial ramp, so the amplitud
do not rise so quick. The final purpose is to make at postprocesing
somekind of phase averages on the particles properties, without having
to cut the beggining of files manually. Nevertheless, it is not much
important. As you pointed out, if you write the input file, you shall
now how the wall will move. This question was also for trying to learn
more how the code is written.
Thanks again for your quick answer. As far as I know, Lammps is a great
code, thanks for having it public and to share your knowledge about it.