Illegal fix nvt/npt/nph command

I am new to lammps and I am working on tutorial. I am facing problem with nanowire deformation example, i am using LAMMPS (11 Nov 2013)

I get this ERROR: Illegal fix nvt/npt/nph command (…/fix_nh.cpp:324)

#-----------------Pressure Equilibriation-----------------------
fix 1 all npt 100.0 100.0 10.0 aniso NULL NULL NULL NULL 0.0 0.0 10 drag 0.3
run 10000
unfix 1
undump 1
shell cd ..
shell mkdir deform
shell cd deform

I made search and realized the syntax npt is updated but I am stuck I don’t know how to change the cod to make it work

please help me to fix it.

thank you

If you are asking how to find the documentation for an older

version of LAMMPS, then that version should have a “doc”

dir with the documentation in it. Failing that,

download one of the older tarballs from the web site,

unpack it, and look at the doc dir in that distro.


I was working on the same tutorial a couple of months ago. So i am a beginner too. I overcame the problem by changing the npt command to this form.
fix 1 all npt temp 100.0 100.0 10.0 aniso 0.0 0.0 10 drag 0.3

It was shown in the lammps manual, i think it’s escaped your notice. I strongly recommend the manual, it has most answers you need.