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<CENTER><A HREF = "http://lammps.sandia.gov">LAMMPS WWW Site</A> - <A HREF = "Manual.html">LAMMPS Documentation</A> - <A HREF = "Section_commands.html#comm">LAMMPS Commands</A>
</CENTER>
<HR>
<H3>reset_timestep command
</H3>
<P><B>Syntax:</B>
</P>
<PRE>reset_timestep N
</PRE>
<UL><LI>N = timestep number
</UL>
<P><B>Examples:</B>
</P>
<PRE>reset_timestep 0
reset_timestep 4000000
</PRE>
<P><B>Description:</B>
</P>
<P>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.
</P>
<P>The <A HREF = "read_data.html">read_data</A> and <A HREF = "create_box.html">create_box</A>
commands set the timestep to 0; the <A HREF = "read_restart.html">read_restart</A>
command sets the timestep to the value it had when the restart file
was written.
</P>
<P><B>Restrictions:</B> none
</P>
<P>This command cannot be used when a dump file is defined via the
<A HREF = "dump.html">dump</A> command and has already been written to. It also
cannot be used when a <A HREF = "restart.html">restart frequency</A> 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 <A HREF = "undump.html">undump</A> command or <A HREF = "restart.html">restart
0</A> 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.
</P>
<P>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 <A HREF = "fix_ave_spatial.html">fix
ave/spatial</A>. Also <A HREF = "fix_dt_reset.html">fix
dt/reset</A> and <A HREF = "fix_deposit.html">fix deposit</A>.
</P>
<P>This command cannot be used when any dynamic regions are defined via
the <A HREF = "region.html">region</A> command, which have time-dependent position
and orientation.
</P>
<P>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. <A HREF = "fix_nh.html">fix nvt</A>, 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.
</P>
<P>Resetting the timestep will clear the flags for <A HREF = "compute.html">computes</A>
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 <A HREF = "variable.html">variable</A>
command for more details.
</P>
<P><B>Related commands:</B> none
</P>
<P><B>Default:</B> none
</P>
</HTML>
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