Re: [lammps-users] average position particles

Dear Axel,

I try to do the following in order to obtain the x,y,z average positions of each atom

compute myAveConf all property/atom ix iy iz
#dump ID group-ID style N file args
dump myAveConf all atom 100 dump.position id type x,y,z
fix all_myAveConf all ave/atom 1 100 100 x y z c_myAveConf[*]

#final equilibration
fix 1 all nve temp 300 300 100
run 1000000
unfix 1

but it does not work

ERROR: Illegal dump atom command (../dump_atom.cpp:32)
Last command: dump myAveConf all atom 100 dump.position id type x,y,z

I tried to read the dump instructions but they are not clear to me, I appreciate if you can help me

it doesn’t work because it is not correct and not done how the documentation describes it.

if you say the documentation is not clear, then you have to explain in detail what is not clear. there are examples and detailed descriptions of what to do.
you cannot expect from a documentation for a software as complex and with so many features to have all details explained and laid out exactly like you need it in your specific case. you have to look up the pieces and put them together yourself. there is the general syntax and then the detailed use of keywords with individual meaning and functionality.
from what you quote, it doesn’t look like you have done much of that and that is why it fails since you are not even meeting the minimum syntax requirements (hence the error).

there isn’t much else that I can explain in an e-mail that would be different from what is written in the manual, short of doing your work and your thinking and telling you exactly what to do. this may be frustrating for you now, but will pay off a lot in the future.