Using "fix move" with randomly varying period time

LAMMPS LAMMPS Mailing List Mirror
1

Hello lammps users,
I would like to use the following command:

fix 1 GroupName move wiggle 0 1 0 $period_time units box

So in each time step the $period_time would vary randomly, generating a white noise.
Is it possible to do that by using variable command, or does it require changes/additions to lammps core?

Thank you very much,
Shahar

2

Hello lammps users,
I would like to use the following command:

fix 1 GroupName move wiggle 0 1 0 $period_time units box

So in each time step the $period_time would vary randomly, generating a
white noise.
Is it possible to do that by using variable command, or does it require
changes/additions to lammps core?

how you would use fix move with a variable is explained in the documentation:

http://lammps.sandia.gov/doc/fix_move.html

please have a closer look and see that the way how you propose to do
it, is not very meaningful. just use a variable directly. please also
note that there are two ways of variable expansion

http://lammps.sandia.gov/doc/variable.html

and that you have chose the "immediate expansion" using the $ sign and
that in this case, the fix move command would not even know that you
are handing in a variable. and on top of that, you are not using the
correct syntax for that. your input cannot work. again, please see the
documentation.

axel.