Thanks for Alex’s kind help.

I’m sorry about the bad description for my question. Actually I want to calculate the thermal conductivity, I adopt the Green-Kubo method, by this method the total energy should keep in a small fluctuation. But for my simulation, I ran the simulation for 10 million steps and the total energy increased about 0.2%. Also I ran the example for calculating thermal conductivity , after I ran 10million steps, the total energy of example also increased about 0.2%, is that normal? If the energy increased a little, is the result reliable? Or can I only count the smooth part of total energy (the total energy is in a fluctuation range) and do the thermal conductivity calculation? For example , if I want to calculate the average of temperature between line 50 to 200, how can I do in Lammps? I can use the matlab to do it, but I don’t how to do in the lammps input. Sorry for these stupid questions, I have bothered by these question for a week, but I can’t found any answer online. It is highly appreciate if anyone can recommend any reference information to me.

Thanks for Alex's kind help.

I'm sorry about the bad description for my question. Actually I want to

calculate the thermal conductivity, I adopt the Green-Kubo method, by this

method the total energy should keep in a small fluctuation. But for my

simulation, I ran the simulation for 10 million steps and the total energy

increased about 0.2%. Also I ran the example for calculating thermal

conductivity , after I ran 10million steps, the total energy of example

also increased about 0.2%, is that normal? If the energy increased a

little, is the result reliable? Or can I only count the smooth part of

total energy (the total energy is in a fluctuation range) and do the

thermal conductivity calculation? For example , if I want to calculate the

average of temperature between line 50 to 200, how can I do in Lammps? I

can use the matlab to do it, but I don't how to do in the lammps input.

Sorry for these stupid questions, I have bothered by these question for a

week, but I can't found any answer online. It is highly appreciate if

anyone can recommend any reference information to me.

nobody can answer these questions in such generality without knowing the

details of your simulations, as mentioned before, this is something to be

discussed with your adviser. please keep in mind, that the fact, that your

adviser is not available to you at the moment, does not entitle you to any

kind of special treatment, or that somebody fills here fills in.

axel.