[lammps-users] How to use fix ave/time and thermo_style costom


I want to obtain the time-averaged themodynamics quantities.

The instantaneous thermodynamics quantities is obtained by
using the command "thermo_style" as follows

  thermo_style custom step etotal pe ke press temp
  thermo_modify norm no
  thermo 1

To obtain the time-averaged quantities,
according to the manual,
I understand that I have to use the fix ave/time command.

But I cannot treat it in an appropriate mannar.

Could you give me the sample command ?


Add these lines to bench/in.lj

fix 2 all ave/time 1 10 10 c_thermo_temp
thermo 10
thermo_style custom step temp f_2


Dear Steve Plimpton

Thank you for teaching.

Can I ask an additional question?

When I use the fix ave/time command,
how to print other thermodynamic quantities,
such as pe, evdwl, ke, etc written
in the thermo_style command in the manual?

Sincerely yours.


Try adding the following lines to bench/in.lj

compute my_temp all temp
compute my_pe all pe
compute my_ke all ke
compute my_evdw all pe pair
fix 2 all ave/time 1 10 10 c_my_temp
fix 3 all ave/time 1 10 10 c_my_pe
fix 4 all ave/time 1 10 10 c_my_ke
fix 5 all ave/time 1 10 10 c_my_evdw
thermo 10
thermo_style custom step temp f_2 pe f_3 ke f_4 evdwl f_5


Dear Paul,
I provided him with variable command alternative. It seems that worked for him. I am replying to you and forum in case anybody else is interested.

variable vd equal evdwl
fix 2 all ave/time 1 10 10 v_vd
thermo_style custom f_2

I think this may be more general as compute is not defined for all thermodynamic keywords.


2008/9/22 Crozier, Paul S <[email protected]>

Dear Crozier, Paul S and Vikas Varshney

I try both method.
And I can obtain what I want.

Both recipes is possible to use.
So, I can learn two method for my purpose.
Thank you for your kindness!

Sincerely yours.

Takenobu Nakamura