2006-09-22 00:22:34 +08:00
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"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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fix drag command :h3
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[Syntax:]
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fix ID group-ID drag x y z fmag delta :pre
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ID, group-ID are documented in "fix"_fix.html command
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drag = style name of this fix command
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x,y,z = coord to drag atoms towards
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fmag = magnitude of force to apply to each atom (force units)
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delta = cutoff distance inside of which force \
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is not applied (distance units) :ul
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[Examples:]
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fix center small-molecule drag 0.0 10.0 0.0 5.0 2.0 :pre
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[Description:]
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Apply a force to each atom in a group to drag it towards the point
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(x,y,z). The magnitude of the force is specified by fmag. If an atom
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is closer than a distance delta to the point, then the force is not
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applied.
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Any of the x,y,z values can be specified as NULL which means do not
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include that dimension in the distance calculation or force
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application.
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This command can be used to steer one or more atoms to a new location
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in the simulation.
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2007-06-26 08:03:39 +08:00
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[Restart, fix_modify, thermo output, run start/stop, minimize info:]
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No information about this fix is written to "binary restart
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files"_restart.html. None of the "fix_modify"_fix_modify.html options
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are relevant to this fix. No quantities calculated by this fix can be
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output by the "thermo_style custom"_thermo_style.html command. No
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parameter of this fix can be used with the {start/stop} keywords of
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the "run"_run.html command. This fix is not invoked during "energy
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minimization"_minimize.html.
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2006-09-22 00:22:34 +08:00
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[Restrictions:] none
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[Related commands:]
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"fix spring"_fix_spring.html
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[Default:] none
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