Files
lammps/doc/write_dump.txt

90 lines
3.6 KiB
Plaintext

"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
write_dump command :h3
[Syntax:]
write_dump ID group-ID style N file dump-args modify dump-modify-args :pre
ID = user-assigned name for the dump (ignored) :ulb,l
group-ID = ID of the group of atoms to be dumped :l
style = any of the supported "dump styles"_dump.html :l
N = dump every this many timesteps (ignored) :l
file = name of file to write dump info to :l
dump-args = any additional args needed for a particular "dump style"_dump.html :l
modify = all args after this keyword are passed to "dump_modify"_dump_modify.html (optional) :l
dump-modify-args = args for "dump_modify"_dump_modify.html (optional) :l,ule
[Examples:]
write_dump 1 all atom 0 dump.atom
write_dump 1 subgroup atom 0 dump.run.bin
write_dump 1 all custom 0 dump.myforce.* id type x y vx fx
write_dump 1 flow custom 0 dump.%.myforce id type c_myF\[3\] v_ke modify sort id
write_dump 1 all xyz 0 system.xyz modify sort id elements O H
write_dump 1 all image 0 snap*.jpg type type size 960 960 modify backcolor white
write_dump 1 all image 0 snap*.jpg element element &
bond atom 0.3 shiny 0.1 ssao yes 6345 0.2 size 1600 1600 &
modify backcolor white element C C O H N C C C O H H S O H :pre
[Description:]
Dump a single snapshot of atom quantities to one or more files for the
current state of the system. This is a one-time operation, in
contrast to the "dump"_dump.html command which will write out multiple
snapshots periodically during a running simulation.
The syntax for this command is identical to that of the
"dump"_dump.html and "dump_modify"_dump_modify.html commands as if
they were concatenated together, with one exception. This is so that
the full range of "dump_modify"_dump_modify.html options can be
specified for the single snapshot, just as they can be for multiple
snapshots. The syntax exception is that if a second set of
dump-modify-args is specified, they must be preceeded by the "modify"
keyword, so that LAMMPS can cleanly separate the two sets of args.
Note that the dump ID and frequency {N} arguments are ignored, since
they are irrelevant when only a single snapshot is being written.
Also note that if the specified filename uses the wildcard characters
"*" or "%", as supported by the "dump"_dump.html commmand, they will
operate in the same fashion to create the new filename(s).
:line
[Restrictions:]
All restrictions for the "dump"_dump.html and
"dump_modify"_dump_modify.html commands apply to this command as well.
For the "dump image"_dump_image.html dump style, this means the
filename is required to contain a '*' character, which will be
replaced by the current timestep.
Since dumps are normally written during a "run"_run.html or "energy
minimization"_minimize.html, the simulation has to be ready to run
before this command can be used. Similarly, if the dump requires
information from a compute, fix, or variable, the information needs to
have been calculated for the current timestep (e.g. by a prior run),
else LAMMPS will generate an error message.
For example, it is not possible to dump per-atom energy with this
command before a run has been performed, since no energies and forces
have yet been calculated. See the "variable"_variable.html doc page
sectinn on Variable Accuracy for more information on this topic.
[Related commands:]
"dump"_dump.html, "dump image"_dump_image.html, "dump_modify"_dump_modify.html
[Default:]
The defaults are listed on the doc pages for the "dump"_dump.html and
"dump image"_dump_image.html and "dump_modify"_dump_modify.html
commands.