forked from lijiext/lammps
63 lines
2.0 KiB
Plaintext
63 lines
2.0 KiB
Plaintext
"LAMMPS WWW Site"_lws - "LAMMPS Documentation"_ld - "LAMMPS Commands"_lc :c
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:link(lws,http://lammps.sandia.gov)
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:link(ld,Manual.html)
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:link(lc,Section_commands.html#comm)
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:line
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compute event/displace command :h3
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[Syntax:]
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compute ID group-ID event/displace threshold :pre
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ID, group-ID are documented in "compute"_compute.html command
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event/displace = style name of this compute command
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threshold = minimum distance anyparticle must move to trigger an event (distance units) :ul
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[Examples:]
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compute 1 all event/displace 0.5 :pre
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[Description:]
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Define a computation that flags an "event" if any particle in the
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group has moved a distance greater than the specified threshold
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distance when compared to a previously stored reference state
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(i.e. the previous event). This compute is typically used in
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conjunction with the "prd"_prd.html and "tad"_tad.html commands,
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to detect if a transition
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to a new minimum energy basin has occurred.
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This value calculated by the compute is equal to 0 if no particle has
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moved far enough, and equal to 1 if one or more particles have moved
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further than the threshold distance.
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NOTE: If the system is undergoing significant center-of-mass motion,
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due to thermal motion, an external force, or an initial net momentum,
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then this compute will not be able to distinguish that motion from
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local atom displacements and may generate "false postives."
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[Output info:]
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This compute calculates a global scalar (the flag). This value can be
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used by any command that uses a global scalar value from a compute as
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input. See "Section_howto 15"_Section_howto.html#howto_15 for an
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overview of LAMMPS output options.
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The scalar value calculated by this compute is "intensive". The
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scalar value will be a 0 or 1 as explained above.
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[Restrictions:]
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This command can only be used if LAMMPS was built with the REPLICA
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package. See the "Making LAMMPS"_Section_start.html#start_3 section
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for more info on packages.
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[Related commands:]
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"prd"_prd.html, "tad"_tad.html
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[Default:] none
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