forked from lijiext/lammps
71 lines
2.0 KiB
Plaintext
71 lines
2.0 KiB
Plaintext
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.. index:: reset_timestep
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reset_timestep command
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======================
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Syntax
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""""""
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.. parsed-literal::
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reset_timestep N
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* N = timestep number
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Examples
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""""""""
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.. parsed-literal::
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reset_timestep 0
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reset_timestep 4000000
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Description
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"""""""""""
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Set the timestep counter to the specified value. This command
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normally comes after the timestep has been set by reading a restart
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file via the :doc:`read_restart <read_restart>` command, or a previous
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simulation advanced the timestep.
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The :doc:`read_data <read_data>` and :doc:`create_box <create_box>`
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commands set the timestep to 0; the :doc:`read_restart <read_restart>`
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command sets the timestep to the value it had when the restart file
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was written.
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Restrictions
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""""""""""""
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none
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This command cannot be used when any fixes are defined that keep track
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of elapsed time to perform certain kinds of time-dependent operations.
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Examples are the :doc:`fix deposit <fix_deposit>` and :doc:`fix dt/reset <fix_dt_reset>` commands. The former adds atoms on
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specific timesteps. The latter keeps track of accumulated time.
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Various fixes use the current timestep to calculate related
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quantities. If the timestep is reset, this may produce unexpected
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behavior, but LAMMPS allows the fixes to be defined even if the
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timestep is reset. For example, commands which thermostat the system,
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e.g. :doc:`fix nvt <fix_nh>`, allow you to specify a target temperature
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which ramps from Tstart to Tstop which may persist over several runs.
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If you change the timestep, you may induce an instantaneous change in
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the target temperature.
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Resetting the timestep clears flags for :doc:`computes <compute>` that
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may have calculated some quantity from a previous run. This means
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these quantity cannot be accessed by a variable in between runs until
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a new run is performed. See the :doc:`variable <variable>` command for
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more details.
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Related commands
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""""""""""""""""
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:doc:`rerun <rerun>`
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**Default:** none
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.. _lws: http://lammps.sandia.gov
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.. _ld: Manual.html
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.. _lc: Section_commands.html#comm
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