lammps-users Digest, Vol 99, Issue 72


Thank you for your reply,

What I want to do is , to dump the velocity of a single particle (Say in every 100 steeps) .

First I create group ID as

group group-1 id [Atom-ID]

then used dump

dump 11 group1 custom 100 test1.* vx vy vz

So what this does is, printing vx, vy and vz at each 100 time steps in separate file (for the fist 100 steps one file…another files for the next 100 steeps)
What I want is to dump all velocities in one single file.


In that case you need to take the wildcard out of the filename (it can’t have any *'s in it). So test1.dump would work perfectly well, for example.

dump 11 group1 custom 100 test1.* vx vy vz

   Oh okay. This is unusual. (To my eyes. This is the first time I
have seen anyone use a wildcard character * in a LAMMPS dump file
   If you don't want to create multiple files, then remove the *
(wildcard character) from the file name.
    For example, try this instead:

dump 11 group1 custom 100 test1.lammpstrj vx vy vz

For more information, check the documentation for the dump command:


(Incidentally, dump files ending in .lammpstrj can be recognized more
easily by VMD)

Thanks Niall

That solves the problem !