"LAMMPS WWW Site"_lws - "LAMMPS Documentation"_ld - "LAMMPS Commands"_lc :c :link(lws,http://lammps.sandia.gov) :link(ld,Manual.html) :link(lc,Section_commands.html#comm) :line reset_timestep command :h3 [Syntax:] reset_timestep N :pre N = timestep number :ul [Examples:] reset_timestep 0 reset_timestep 4000000 :pre [Description:] Set the timestep counter to the specified value. This command normally comes after the timestep has been set by reading it in from a file or a previous simulation advanced the timestep. The "read_data"_read_data.html and "create_box"_create_box.html commands set the timestep to 0; the "read_restart"_read_restart.html command sets the timestep to the value it had when the restart file was written. [Restrictions:] none This command cannot be used when a dump file is defined via the "dump"_dump.html command and has already been written to. It also cannot be used when a "restart frequency"_restart.html has been set, and a restart file has already been written. This is because the changed timestep can mess up the planned timestep for the next file write. See the "undump"_undump.html command or "restart 0"_restart.html command for info on how to turn off these definitions if necessary. New specifications for dump and restart files can be given after the reset_timestep command is used. This command cannot be used when any fixes are defined that keep track of elapsed time to perform time-dependent operations. Examples include the "ave" fixes such as "fix ave/spatial"_fix_ave_spatial.html. Also "fix dt/reset"_fix_dt_reset.html and "fix deposit"_fix_deposit.html. This command cannot be used when any dynamic regions are defined via the "region"_region.html command, which have time-dependent position and orientation. There are other fixes which use the current timestep which may produce unexpected behavior, but LAMMPS allows them to be in place when resetting the timestep. For example, commands which thermostat the system, e.g. "fix nvt"_fix_nh.html, allow you to specify a target temperature which ramps from Tstart to Tstop which may persist over several runs. If you change the timestep, you may change the target temperature. Resetting the timestep will clear the flags for "computes"_compute.html that may have calculated some quantity from a previous run. This means that quantity cannot be accessed by a variable in between runs until a new run is performed. See the "variable"_variable.html command for more details. [Related commands:] none [Default:] none