Reset_timestep shows error with compute temperature command

Respected lammps users, When I try to melt iron and calculate temperature using compute command ; After I perform equilibration and use reset_time step 0 to continue the system for another simulation it gives error of not using it with compute temperature command.
Secondly when I continue simulation without using reset timestep and just unfix nvt ensemble, it gives different results of thermostyle variables. Is it necessary to use reset_time step?
What command should I use to use the previous simulation state to be continued?

Thanks for cooperation

You are not making it easy to help you. A few suggestions:

  • always state which version of LAMMPS you are using
  • keep in mind that people know nothing about you, your expertise/experience and your research
  • when you get error messages , please quote the exact error message and best provide a minimal input example that reproduces it. Especially, if you believe that this error should not happen and is in conflict with the documentation.
  • when you describe what you do, you leave out a lot of important context. Best practice, again, is to construct a minimal input and post it. It doesn’t have to be for your research simulation but could just be some input that has as few atoms and commands needed to reproduce the observed situation. If you don’t provide it, you force people to construct one by themselves and that is a lot of extra effort, so your chances of getting help drops exponentially with the complexity of the situation you are describing.

Without the context of your complete input, it is impossible to make sense of what you are asking. Generally, there should be no difference in a simulation whether you using reset_timestep or not unless you are using a command that has time dependent settings. If you say “different”, that can mean a lot of things. Since we don’t have the benefit of seeing what you see on your computer and knowing what you are doing, it is impossible to understand what is going on.

LAMMPS preserves the current state. If the simulation does not continue unchanged, there must be something that you have changed in between that has an impact.