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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>
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			<HR>

			<H3>dump command
			</H3>
			<H3><A HREF = "dump_h5md.html">dump h5md</A> command
			</H3>
			<H3><A HREF = "dump_image.html">dump image</A> command
			</H3>
			<H3><A HREF = "dump_image.html">dump movie</A> command
			</H3>
			<H3><A HREF = "dump_molfile.html">dump molfile</A> command
			</H3>
			<P><B>Syntax:</B>
			</P>
			<PRE>dump ID group-ID style N file args
			</PRE>
			<UL><LI>ID = user-assigned name for the dump

			<LI>group-ID = ID of the group of atoms to be dumped

			<LI>style = <I>atom</I> or <I>atom/gz</I> or <I>atom/mpiio</I> or <I>cfg</I> or <I>cfg/gz</I> or <I>cfg/mpiio</I> or <I>dcd</I> or <I>xtc</I> or <I>xyz</I> or <I>xyz/gz</I> or <I>xyz/mpiio</I> or <I>h5md</I> or <I>image</I> or <I>movie</I> or <I>molfile</I> or <I>local</I> or <I>custom</I> or <I>custom/gz</I> or <I>custom/mpiio</I>

			<LI>N = dump every this many timesteps

			<LI>file = name of file to write dump info to

			<LI>args = list of arguments for a particular style

			<PRE> <I>atom</I> args = none
			<I>atom/gz</I> args = none
			<I>atom/mpiio</I> args = none
			<I>cfg</I> args = same as <I>custom</I> args, see below
			<I>cfg/gz</I> args = same as <I>custom</I> args, see below
			<I>cfg/mpiio</I> args = same as <I>custom</I> args, see below
			<I>dcd</I> args = none
			<I>xtc</I> args = none
			<I>xyz</I> args = none
			</PRE>
			<PRE> <I>xyz/gz</I> args = none
			</PRE>
			<PRE> <I>xyz/mpiio</I> args = none
			</PRE>
			<PRE> <I>h5md</I> args = discussed on <A HREF = "dump_h5md.html">dump h5md</A> doc page
			</PRE>
			<PRE> <I>image</I> args = discussed on <A HREF = "dump_image.html">dump image</A> doc page
			</PRE>
			<PRE> <I>movie</I> args = discussed on <A HREF = "dump_image.html">dump image</A> doc page
			</PRE>
			<PRE> <I>molfile</I> args = discussed on <A HREF = "dump_molfile.html">dump molfile</A> doc page
			</PRE>
			<PRE> <I>local</I> args = list of local attributes
			possible attributes = index, c_ID, c_ID[N], f_ID, f_ID[N]
			index = enumeration of local values
			c_ID = local vector calculated by a compute with ID
			c_ID[N] = Nth column of local array calculated by a compute with ID
			f_ID = local vector calculated by a fix with ID
			f_ID[N] = Nth column of local array calculated by a fix with ID
			</PRE>
			<PRE> <I>custom</I> or <I>custom/gz</I> or <I>custom/mpiio</I> args = list of atom attributes
			possible attributes = id, mol, proc, procp1, type, element, mass,
			x, y, z, xs, ys, zs, xu, yu, zu,
			xsu, ysu, zsu, ix, iy, iz,
			vx, vy, vz, fx, fy, fz,
			q, mux, muy, muz, mu,
			radius, diameter, omegax, omegay, omegaz,
			angmomx, angmomy, angmomz, tqx, tqy, tqz,
			c_ID, c_ID[N], f_ID, f_ID[N], v_name
			</PRE>
			<PRE> id = atom ID
			mol = molecule ID
			proc = ID of processor that owns atom
			procp1 = ID+1 of processor that owns atom
			type = atom type
			element = name of atom element, as defined by <A HREF = "dump_modify.html">dump_modify</A> command
			mass = atom mass
			x,y,z = unscaled atom coordinates
			xs,ys,zs = scaled atom coordinates
			xu,yu,zu = unwrapped atom coordinates
			xsu,ysu,zsu = scaled unwrapped atom coordinates
			ix,iy,iz = box image that the atom is in
			vx,vy,vz = atom velocities
			fx,fy,fz = forces on atoms
			q = atom charge
			mux,muy,muz = orientation of dipole moment of atom
			mu = magnitude of dipole moment of atom
			radius,diameter = radius,diameter of spherical particle
			omegax,omegay,omegaz = angular velocity of spherical particle
			angmomx,angmomy,angmomz = angular momentum of aspherical particle
			tqx,tqy,tqz = torque on finite-size particles
			c_ID = per-atom vector calculated by a compute with ID
			c_ID[N] = Nth column of per-atom array calculated by a compute with ID
			f_ID = per-atom vector calculated by a fix with ID
			f_ID[N] = Nth column of per-atom array calculated by a fix with ID
			v_name = per-atom vector calculated by an atom-style variable with name
			d_name = per-atom floating point vector with name, managed by fix property/atom
			i_name = per-atom integer vector with name, managed by fix property/atom
			</PRE>

			</UL>
			<P><B>Examples:</B>
			</P>
			<PRE>dump myDump all atom 100 dump.atom
			dump myDump all atom/mpiio 100 dump.atom.mpiio
			dump myDump all atom/gz 100 dump.atom.gz
			dump 2 subgroup atom 50 dump.run.bin
			dump 2 subgroup atom 50 dump.run.mpiio.bin
			dump 4a all custom 100 dump.myforce.* id type x y vx fx
			dump 4b flow custom 100 dump.%.myforce id type c_myF[3] v_ke
			dump 2 inner cfg 10 dump.snap.*.cfg mass type xs ys zs vx vy vz
			dump snap all cfg 100 dump.config.*.cfg mass type xs ys zs id type c_Stress[2]
			dump 1 all xtc 1000 file.xtc
			</PRE>
			<P><B>Description:</B>
			</P>
			<P>Dump a snapshot of atom quantities to one or more files every N
			timesteps in one of several styles. The <I>image</I> and <I>movie</I> styles are
			the exception: the <I>image</I> style renders a JPG, PNG, or PPM image file
			of the atom configuration every N timesteps while the <I>movie</I> style
			combines and compresses them into a movie file; both are discussed in
			detail on the <A HREF = "dump_image.html">dump image</A> doc page. The timesteps on
			which dump output is written can also be controlled by a variable.
			See the <A HREF = "dump_modify.html">dump_modify every</A> command.
			</P>
			<P>Only information for atoms in the specified group is dumped. The
			<A HREF = "dump_modify.html">dump_modify thresh and region</A> commands can also
			alter what atoms are included. Not all styles support all these
			options; see details below.
			</P>
			<P>As described below, the filename determines the kind of output (text
			or binary or gzipped, one big file or one per timestep, one big file
			or multiple smaller files).
			</P>
			<P>IMPORTANT NOTE: Because periodic boundary conditions are enforced only
			on timesteps when neighbor lists are rebuilt, the coordinates of an
			atom written to a dump file may be slightly outside the simulation
			box.
			</P>
			<P>IMPORTANT NOTE: Unless the <A HREF = "dump_modify.html">dump_modify sort</A> option
			is invoked, the lines of atom information written to dump files
			(typically one line per atom) will be in an indeterminate order for
			each snapshot. This is even true when running on a single processor,
			if the <A HREF = "atom_modify.html">atom_modify sort</A> option is on, which it is
			by default. In this case atoms are re-ordered periodically during a
			simulation, due to spatial sorting. It is also true when running in
			parallel, because data for a single snapshot is collected from
			multiple processors, each of which owns a subset of the atoms.
			</P>
			<P>For the <I>atom</I>, <I>custom</I>, <I>cfg</I>, and <I>local</I> styles, sorting is off by
			default. For the <I>dcd</I>, <I>xtc</I>, <I>xyz</I>, and <I>molfile</I> styles, sorting by
			atom ID is on by default. See the <A HREF = "dump_modify.html">dump_modify</A> doc
			page for details.
			</P>
			<P>The <I>atom/gz</I>, <I>cfg/gz</I>, <I>custom/gz</I>, and <I>xyz/gz</I> styles are identical
			in command syntax to the corresponding styles without "gz", however,
			they generate compressed files using the zlib library. Thus the filename
			suffix ".gz" is mandatory. This is an alternative approach to writing
			compressed files via a pipe, as done by the regular dump styles, which
			may be required on clusters where the interface to the high-speed network
			disallows using the fork() library call (which is needed for a pipe).
			For the remainder of this doc page, you should thus consider the <I>atom</I>
			and <I>atom/gz</I> styles (etc) to be inter-changeable, with the exception
			of the required filename suffix.
			</P>
			<P>As explained below, the <I>atom/mpiio</I>, <I>cfg/mpiio</I>, <I>custom/mpiio</I>, and
			<I>xyz/mpiio</I> styles are identical in command syntax and in the format
			of the dump files they create, to the corresponding styles without
			"mpiio", except the single dump file they produce is written in
			parallel via the MPI-IO library. For the remainder of this doc page,
			you should thus consider the <I>atom</I> and <I>atom/mpiio</I> styles (etc) to
			be inter-changeable. The one exception is how the filename is
			specified for the MPI-IO styles, as explained below.
			</P>
			<HR>

			<P>The <I>style</I> keyword determines what atom quantities are written to the
			file and in what format. Settings made via the
			<A HREF = "dump_modify.html">dump_modify</A> command can also alter the format of
			individual values and the file itself.
			</P>
			<P>The <I>atom</I>, <I>local</I>, and <I>custom</I> styles create files in a simple text
			format that is self-explanatory when viewing a dump file. Many of the
			LAMMPS <A HREF = "Section_tools.html">post-processing tools</A>, including
			<A HREF = "http://www.sandia.gov/~sjplimp/pizza.html">Pizza.py</A>, work with this
			format, as does the <A HREF = "rerun.html">rerun</A> command.
			</P>
			<P>For post-processing purposes the <I>atom</I>, <I>local</I>, and <I>custom</I> text
			files are self-describing in the following sense.
			</P>
			<P>The dimensions of the simulation box are included in each snapshot.
			For an orthogonal simulation box this information is is formatted as:
			</P>
			<PRE>ITEM: BOX BOUNDS xx yy zz
			xlo xhi
			ylo yhi
			zlo zhi
			</PRE>
			<P>where xlo,xhi are the maximum extents of the simulation box in the
			x-dimension, and similarly for y and z. The "xx yy zz" represent 6
			characters that encode the style of boundary for each of the 6
			simulation box boundaries (xlo,xhi and ylo,yhi and zlo,zhi). Each of
			the 6 characters is either p = periodic, f = fixed, s = shrink wrap,
			or m = shrink wrapped with a minimum value. See the
			<A HREF = "boundary.html">boundary</A> command for details.
			</P>
			<P>For triclinic simulation boxes (non-orthogonal), an orthogonal
			bounding box which encloses the triclinic simulation box is output,
			along with the 3 tilt factors (xy, xz, yz) of the triclinic box,
			formatted as follows:
			</P>
			<PRE>ITEM: BOX BOUNDS xy xz yz xx yy zz
			xlo_bound xhi_bound xy
			ylo_bound yhi_bound xz
			zlo_bound zhi_bound yz
			</PRE>
			<P>The presence of the text "xy xz yz" in the ITEM line indicates that
			the 3 tilt factors will be included on each of the 3 following lines.
			This bounding box is convenient for many visualization programs. The
			meaning of the 6 character flags for "xx yy zz" is the same as above.
			</P>
			<P>Note that the first two numbers on each line are now xlo_bound instead
			of xlo, etc, since they repesent a bounding box. See <A HREF = "Section_howto.html#howto_12">this
			section</A> of the doc pages for a geometric
			description of triclinic boxes, as defined by LAMMPS, simple formulas
			for how the 6 bounding box extents (xlo_bound,xhi_bound,etc) are
			calculated from the triclinic parameters, and how to transform those
			parameters to and from other commonly used triclinic representations.
			</P>
			<P>The "ITEM: ATOMS" line in each snapshot lists column descriptors for
			the per-atom lines that follow. For example, the descriptors would be
			"id type xs ys zs" for the default <I>atom</I> style, and would be the atom
			attributes you specify in the dump command for the <I>custom</I> style.
			</P>
			<P>For style <I>atom</I>, atom coordinates are written to the file, along with
			the atom ID and atom type. By default, atom coords are written in a
			scaled format (from 0 to 1). I.e. an x value of 0.25 means the atom
			is at a location 1/4 of the distance from xlo to xhi of the box
			boundaries. The format can be changed to unscaled coords via the
			<A HREF = "dump_modify.html">dump_modify</A> settings. Image flags can also be
			added for each atom via dump_modify.
			</P>
			<P>Style <I>custom</I> allows you to specify a list of atom attributes to be
			written to the dump file for each atom. Possible attributes are
			listed above and will appear in the order specified. You cannot
			specify a quantity that is not defined for a particular simulation -
			such as <I>q</I> for atom style <I>bond</I>, since that atom style doesn't
			assign charges. Dumps occur at the very end of a timestep, so atom
			attributes will include effects due to fixes that are applied during
			the timestep. An explanation of the possible dump custom attributes
			is given below.
			</P>
			<P>For style <I>local</I>, local output generated by <A HREF = "compute.html">computes</A>
			and <A HREF = "fix.html">fixes</A> is used to generate lines of output that is
			written to the dump file. This local data is typically calculated by
			each processor based on the atoms it owns, but there may be zero or
			more entities per atom, e.g. a list of bond distances. An explanation
			of the possible dump local attributes is given below. Note that by
			using input from the <A HREF = "compute_property_local.html">compute
			property/local</A> command with dump local,
			it is possible to generate information on bonds, angles, etc that can
			be cut and pasted directly into a data file read by the
			<A HREF = "read_data.html">read_data</A> command.
			</P>
			<P>Style <I>cfg</I> has the same command syntax as style <I>custom</I> and writes
			extended CFG format files, as used by the
			<A HREF = "http://mt.seas.upenn.edu/Archive/Graphics/A">AtomEye</A> visualization
			package. Since the extended CFG format uses a single snapshot of the
			system per file, a wildcard "*" must be included in the filename, as
			discussed below. The list of atom attributes for style <I>cfg</I> must
			begin with either "mass type xs ys zs" or "mass type xsu ysu zsu"
			since these quantities are needed to write the CFG files in the
			appropriate format (though the "mass" and "type" fields do not appear
			explicitly in the file). Any remaining attributes will be stored as
			"auxiliary properties" in the CFG files. Note that you will typically
			want to use the <A HREF = "dump_modify.html">dump_modify element</A> command with
			CFG-formatted files, to associate element names with atom types, so
			that AtomEye can render atoms appropriately. When unwrapped
			coordinates <I>xsu</I>, <I>ysu</I>, and <I>zsu</I> are requested, the nominal AtomEye
			periodic cell dimensions are expanded by a large factor UNWRAPEXPAND =
			10.0, which ensures atoms that are displayed correctly for up to
			UNWRAPEXPAND/2 periodic boundary crossings in any direction. Beyond
			this, AtomEye will rewrap the unwrapped coordinates. The expansion
			causes the atoms to be drawn farther away from the viewer, but it is
			easy to zoom the atoms closer, and the interatomic distances are
			unaffected.
			</P>
			<P>The <I>dcd</I> style writes DCD files, a standard atomic trajectory format
			used by the CHARMM, NAMD, and XPlor molecular dynamics packages. DCD
			files are binary and thus may not be portable to different machines.
			The number of atoms per snapshot cannot change with the <I>dcd</I> style.
			The <I>unwrap</I> option of the <A HREF = "dump_modify.html">dump_modify</A> command
			allows DCD coordinates to be written "unwrapped" by the image flags
			for each atom. Unwrapped means that if the atom has passed through
			a periodic boundary one or more times, the value is printed for what
			the coordinate would be if it had not been wrapped back into the
			periodic box. Note that these coordinates may thus be far outside
			the box size stored with the snapshot.
			</P>
			<P>The <I>xtc</I> style writes XTC files, a compressed trajectory format used
			by the GROMACS molecular dynamics package, and described
			<A HREF = "http://manual.gromacs.org/current/online/xtc.html">here</A>.
			The precision used in XTC files can be adjusted via the
			<A HREF = "dump_modify.html">dump_modify</A> command. The default value of 1000
			means that coordinates are stored to 1/1000 nanometer accuracy. XTC
			files are portable binary files written in the NFS XDR data format,
			so that any machine which supports XDR should be able to read them.
			The number of atoms per snapshot cannot change with the <I>xtc</I> style.
			The <I>unwrap</I> option of the <A HREF = "dump_modify.html">dump_modify</A> command allows
			XTC coordinates to be written "unwrapped" by the image flags for each
			atom. Unwrapped means that if the atom has passed thru a periodic
			boundary one or more times, the value is printed for what the
			coordinate would be if it had not been wrapped back into the periodic
			box. Note that these coordinates may thus be far outside the box size
			stored with the snapshot.
			</P>
			<P>The <I>xyz</I> style writes XYZ files, which is a simple text-based
			coordinate format that many codes can read. Specifically it has
			a line with the number of atoms, then a comment line that is
			usually ignored followed by one line per atom with the atom type
			and the x-, y-, and z-coordinate of that atom. You can use the
			<A HREF = "dump_modify.html">dump_modify element</A> option to change the output
			from using the (numerical) atom type to an element name (or some
			other label). This will help many visualization programs to guess
			bonds and colors.
			</P>
			<P>Note that <I>atom</I>, <I>custom</I>, <I>dcd</I>, <I>xtc</I>, and <I>xyz</I> style dump files
			can be read directly by <A HREF = "http://www.ks.uiuc.edu/Research/vmd">VMD</A>, a
			popular molecular viewing program. See <A HREF = "Section_tools.html#vmd">Section
			tools</A> of the manual and the
			tools/lmp2vmd/README.txt file for more information about support in
			VMD for reading and visualizing LAMMPS dump files.
			</P>
			<HR>

			<P>Dumps are performed on timesteps that are a multiple of N (including
			timestep 0) and on the last timestep of a minimization if the
			minimization converges. Note that this means a dump will not be
			performed on the initial timestep after the dump command is invoked,
			if the current timestep is not a multiple of N. This behavior can be
			changed via the <A HREF = "dump_modify.html">dump_modify first</A> command, which
			can also be useful if the dump command is invoked after a minimization
			ended on an arbitrary timestep. N can be changed between runs by
			using the <A HREF = "dump_modify.html">dump_modify every</A> command (not allowed
			for <I>dcd</I> style). The <A HREF = "dump_modify.html">dump_modify every</A> command
			also allows a variable to be used to determine the sequence of
			timesteps on which dump files are written. In this mode a dump on the
			first timestep of a run will also not be written unless the
			<A HREF = "dump_modify.html">dump_modify first</A> command is used.
			</P>
			<P>The specified filename determines how the dump file(s) is written.
			The default is to write one large text file, which is opened when the
			dump command is invoked and closed when an <A HREF = "undump.html">undump</A>
			command is used or when LAMMPS exits. For the <I>dcd</I> and <I>xtc</I> styles,
			this is a single large binary file.
			</P>
			<P>Dump filenames can contain two wildcard characters. If a "*"
			character appears in the filename, then one file per snapshot is
			written and the "*" character is replaced with the timestep value.
			For example, tmp.dump.* becomes tmp.dump.0, tmp.dump.10000,
			tmp.dump.20000, etc. This option is not available for the <I>dcd</I> and
			<I>xtc</I> styles. Note that the <A HREF = "dump_modify.html">dump_modify pad</A>
			command can be used to insure all timestep numbers are the same length
			(e.g. 00010), which can make it easier to read a series of dump files
			in order with some post-processing tools.
			</P>
			<P>If a "%" character appears in the filename, then each of P processors
			writes a portion of the dump file, and the "%" character is replaced
			with the processor ID from 0 to P-1. For example, tmp.dump.% becomes
			tmp.dump.0, tmp.dump.1, ... tmp.dump.P-1, etc. This creates smaller
			files and can be a fast mode of output on parallel machines that
			support parallel I/O for output. This option is not available for the
			<I>dcd</I>, <I>xtc</I>, and <I>xyz</I> styles.
			</P>
			<P>By default, P = the number of processors meaning one file per
			processor, but P can be set to a smaller value via the <I>nfile</I> or
			<I>fileper</I> keywords of the <A HREF = "dump_modify.html">dump_modify</A> command.
			These options can be the most efficient way of writing out dump files
			when running on large numbers of processors.
			</P>
			<P>Note that using the "*" and "%" characters together can produce a
			large number of small dump files!
			</P>
			<P>For the <I>atom/mpiio</I>, <I>cfg/mpiio</I>, <I>custom/mpiio</I>, and <I>xyz/mpiio</I>
			styles, a single dump file is written in parallel via the MPI-IO
			library, which is part of the MPI standard for versions 2.0 and above.
			Using MPI-IO requires two steps. First, build LAMMPS with its MPIIO
			package installed, e.g.
			</P>
			<PRE>make yes-mpiio # installs the MPIIO package
			make g++ # build LAMMPS for your platform
			</PRE>
			<P>Second, use a dump filename which contains ".mpiio". Note that it
			does not have to end in ".mpiio", just contain those characters.
			Unlike MPI-IO restart files, which must be both written and read using
			MPI-IO, the dump files produced by these MPI-IO styles are identical
			in format to the files produced by their non-MPI-IO style
			counterparts. This means you can write a dump file using MPI-IO and
			use the <A HREF = "read_dump.html">read_dump</A> command or perform other
			post-processing, just as if the dump file was not written using
			MPI-IO.
			</P>
			<P>Note that MPI-IO dump files are one large file which all processors
			write to. You thus cannot use the "%" wildcard character described
			above in the filename since that specifies generation of multiple
			files. You can use the ".bin" suffix described below in an MPI-IO
			dump file; again this file will be written in parallel and have the
			same binary format as if it were written without MPI-IO.
			</P>
			<P>If the filename ends with ".bin", the dump file (or files, if "*" or
			"%" is also used) is written in binary format. A binary dump file
			will be about the same size as a text version, but will typically
			write out much faster. Of course, when post-processing, you will need
			to convert it back to text format (see the <A HREF = "Section_tools.html#binary">binary2txt
			tool</A>) or write your own code to read the
			binary file. The format of the binary file can be understood by
			looking at the tools/binary2txt.cpp file. This option is only
			available for the <I>atom</I> and <I>custom</I> styles.
			</P>
			<P>If the filename ends with ".gz", the dump file (or files, if "*" or "%"
			is also used) is written in gzipped format. A gzipped dump file will
			be about 3x smaller than the text version, but will also take longer
			to write. This option is not available for the <I>dcd</I> and <I>xtc</I>
			styles.
			</P>
			<HR>

			<P>This section explains the local attributes that can be specified as
			part of the <I>local</I> style.
			</P>
			<P>The <I>index</I> attribute can be used to generate an index number from 1
			to N for each line written into the dump file, where N is the total
			number of local datums from all processors, or lines of output that
			will appear in the snapshot. Note that because data from different
			processors depend on what atoms they currently own, and atoms migrate
			between processor, there is no guarantee that the same index will be
			used for the same info (e.g. a particular bond) in successive
			snapshots.
			</P>
			<P>The <I>c_ID</I> and <I>c_ID[N]</I> attributes allow local vectors or arrays
			calculated by a <A HREF = "compute.html">compute</A> to be output. The ID in the
			attribute should be replaced by the actual ID of the compute that has
			been defined previously in the input script. See the
			<A HREF = "compute.html">compute</A> command for details. There are computes for
			calculating local information such as indices, types, and energies for
			bonds and angles.
			</P>
			<P>Note that computes which calculate global or per-atom quantities, as
			opposed to local quantities, cannot be output in a dump local command.
			Instead, global quantities can be output by the <A HREF = "thermo_style.html">thermo_style
			custom</A> command, and per-atom quantities can be
			output by the dump custom command.
			</P>
			<P>If <I>c_ID</I> is used as a attribute, then the local vector calculated by
			the compute is printed. If <I>c_ID[N]</I> is used, then N must be in the
			range from 1-M, which will print the Nth column of the M-length local
			array calculated by the compute.
			</P>
			<P>The <I>f_ID</I> and <I>f_ID[N]</I> attributes allow local vectors or arrays
			calculated by a <A HREF = "fix.html">fix</A> to be output. The ID in the attribute
			should be replaced by the actual ID of the fix that has been defined
			previously in the input script.
			</P>
			<P>If <I>f_ID</I> is used as a attribute, then the local vector calculated by
			the fix is printed. If <I>f_ID[N]</I> is used, then N must be in the
			range from 1-M, which will print the Nth column of the M-length local
			array calculated by the fix.
			</P>
			<P>Here is an example of how to dump bond info for a system,
			including the distance and energy of each bond:
			</P>
			<PRE>compute 1 all property/local batom1 batom2 btype
			compute 2 all bond/local dist eng
			dump 1 all local 1000 tmp.dump index c_1[1] c_1[2] c_1[3] c_2[1] c_2[2]
			</PRE>
			<HR>

			<P>This section explains the atom attributes that can be specified as
			part of the <I>custom</I> and <I>cfg</I> styles.
			</P>
			<P>The <I>id</I>, <I>mol</I>, <I>proc</I>, <I>procp1</I>, <I>type</I>, <I>element</I>, <I>mass</I>, <I>vx</I>,
			<I>vy</I>, <I>vz</I>, <I>fx</I>, <I>fy</I>, <I>fz</I>, <I>q</I> attributes are self-explanatory.
			</P>
			<P><I>Id</I> is the atom ID. <I>Mol</I> is the molecule ID, included in the data
			file for molecular systems. <I>Proc</I> is the ID of the processor (0 to
			Nprocs-1) that currently owns the atom. <I>Procp1</I> is the proc ID+1,
			which can be convenient in place of a <I>type</I> attribute (1 to Ntypes)
			for coloring atoms in a visualization program. <I>Type</I> is the atom
			type (1 to Ntypes). <I>Element</I> is typically the chemical name of an
			element, which you must assign to each type via the <A HREF = "dump_modify.html">dump_modify
			element</A> command. More generally, it can be any
			string you wish to associated with an atom type. <I>Mass</I> is the atom
			mass. <I>Vx</I>, <I>vy</I>, <I>vz</I>, <I>fx</I>, <I>fy</I>, <I>fz</I>, and <I>q</I> are components of
			atom velocity and force and atomic charge.
			</P>
			<P>There are several options for outputting atom coordinates. The <I>x</I>,
			<I>y</I>, <I>z</I> attributes write atom coordinates "unscaled", in the
			appropriate distance <A HREF = "units.html">units</A> (Angstroms, sigma, etc). Use
			<I>xs</I>, <I>ys</I>, <I>zs</I> if you want the coordinates "scaled" to the box size,
			so that each value is 0.0 to 1.0. If the simulation box is triclinic
			(tilted), then all atom coords will still be between 0.0 and 1.0. Use
			<I>xu</I>, <I>yu</I>, <I>zu</I> if you want the coordinates "unwrapped" by the image
			flags for each atom. Unwrapped means that if the atom has passed thru
			a periodic boundary one or more times, the value is printed for what
			the coordinate would be if it had not been wrapped back into the
			periodic box. Note that using <I>xu</I>, <I>yu</I>, <I>zu</I> means that the
			coordinate values may be far outside the box bounds printed with the
			snapshot. Using <I>xsu</I>, <I>ysu</I>, <I>zsu</I> is similar to using <I>xu</I>, <I>yu</I>, <I>zu</I>,
			except that the unwrapped coordinates are scaled by the box size. Atoms
			that have passed through a periodic boundary will have the corresponding
			cooordinate increased or decreased by 1.0.
			</P>
			<P>The image flags can be printed directly using the <I>ix</I>, <I>iy</I>, <I>iz</I>
			attributes. For periodic dimensions, they specify which image of the
			simulation box the atom is considered to be in. An image of 0 means
			it is inside the box as defined. A value of 2 means add 2 box lengths
			to get the true value. A value of -1 means subtract 1 box length to
			get the true value. LAMMPS updates these flags as atoms cross
			periodic boundaries during the simulation.
			</P>
			<P>The <I>mux</I>, <I>muy</I>, <I>muz</I> attributes are specific to dipolar systems
			defined with an atom style of <I>dipole</I>. They give the orientation of
			the atom's point dipole moment. The <I>mu</I> attribute gives the
			magnitude of the atom's dipole moment.
			</P>
			<P>The <I>radius</I> and <I>diameter</I> attributes are specific to spherical
			particles that have a finite size, such as those defined with an atom
			style of <I>sphere</I>.
			</P>
			<P>The <I>omegax</I>, <I>omegay</I>, and <I>omegaz</I> attributes are specific to
			finite-size spherical particles that have an angular velocity. Only
			certain atom styles, such as <I>sphere</I> define this quantity.
			</P>
			<P>The <I>angmomx</I>, <I>angmomy</I>, and <I>angmomz</I> attributes are specific to
			finite-size aspherical particles that have an angular momentum. Only
			the <I>ellipsoid</I> atom style defines this quantity.
			</P>
			<P>The <I>tqx</I>, <I>tqy</I>, <I>tqz</I> attributes are for finite-size particles that
			can sustain a rotational torque due to interactions with other
			particles.
			</P>
			<P>The <I>c_ID</I> and <I>c_ID[N]</I> attributes allow per-atom vectors or arrays
			calculated by a <A HREF = "compute.html">compute</A> to be output. The ID in the
			attribute should be replaced by the actual ID of the compute that has
			been defined previously in the input script. See the
			<A HREF = "compute.html">compute</A> command for details. There are computes for
			calculating the per-atom energy, stress, centro-symmetry parameter,
			and coordination number of individual atoms.
			</P>
			<P>Note that computes which calculate global or local quantities, as
			opposed to per-atom quantities, cannot be output in a dump custom
			command. Instead, global quantities can be output by the
			<A HREF = "thermo_style.html">thermo_style custom</A> command, and local quantities
			can be output by the dump local command.
			</P>
			<P>If <I>c_ID</I> is used as a attribute, then the per-atom vector calculated
			by the compute is printed. If <I>c_ID[N]</I> is used, then N must be in
			the range from 1-M, which will print the Nth column of the M-length
			per-atom array calculated by the compute.
			</P>
			<P>The <I>f_ID</I> and <I>f_ID[N]</I> attributes allow vector or array per-atom
			quantities calculated by a <A HREF = "fix.html">fix</A> to be output. The ID in the
			attribute should be replaced by the actual ID of the fix that has been
			defined previously in the input script. The <A HREF = "fix_ave_atom.html">fix
			ave/atom</A> command is one that calculates per-atom
			quantities. Since it can time-average per-atom quantities produced by
			any <A HREF = "compute.html">compute</A>, <A HREF = "fix.html">fix</A>, or atom-style
			<A HREF = "variable.html">variable</A>, this allows those time-averaged results to
			be written to a dump file.
			</P>
			<P>If <I>f_ID</I> is used as a attribute, then the per-atom vector calculated
			by the fix is printed. If <I>f_ID[N]</I> is used, then N must be in the
			range from 1-M, which will print the Nth column of the M-length
			per-atom array calculated by the fix.
			</P>
			<P>The <I>v_name</I> attribute allows per-atom vectors calculated by a
			<A HREF = "variable.html">variable</A> to be output. The name in the attribute
			should be replaced by the actual name of the variable that has been
			defined previously in the input script. Only an atom-style variable
			can be referenced, since it is the only style that generates per-atom
			values. Variables of style <I>atom</I> can reference individual atom
			attributes, per-atom atom attributes, thermodynamic keywords, or
			invoke other computes, fixes, or variables when they are evaluated, so
			this is a very general means of creating quantities to output to a
			dump file.
			</P>
			<P>The <I>d_name</I> and <I>i_name</I> attributes allow to output custom per atom
			floating point or integer properties that are managed by
			<A HREF = "fix_property_atom.html">fix property/atom</A>.
			</P>
			<P>See <A HREF = "Section_modify.html">Section_modify</A> of the manual for information
			on how to add new compute and fix styles to LAMMPS to calculate
			per-atom quantities which could then be output into dump files.
			</P>
			<HR>

			<P><B>Restrictions:</B>
			</P>
			<P>To write gzipped dump files, you must either compile LAMMPS with the
			-DLAMMPS_GZIP option or use the styles from the COMPRESS package
			- see the <A HREF = "Section_start.html#start_2">Making LAMMPS</A> section of
			the documentation.
			</P>
			<P>The <I>atom/gz</I>, <I>cfg/gz</I>, <I>custom/gz</I>, and <I>xyz/gz</I> styles are part
			of the COMPRESS package. They are only enabled if LAMMPS was built
			with that package. See the <A HREF = "Section_start.html#start_3">Making
			LAMMPS</A> section for more info.
			</P>
			<P>The <I>atom/mpiio</I>, <I>cfg/mpiio</I>, <I>custom/mpiio</I>, and <I>xyz/mpiio</I> styles
			are part of the MPIIO package. They are only enabled if LAMMPS was
			built with that package. See the <A HREF = "Section_start.html#start_3">Making
			LAMMPS</A> section for more info.
			</P>
			<P>The <I>xtc</I> style is part of the XTC package. It is only enabled if
			LAMMPS was built with that package. See the <A HREF = "Section_start.html#start_3">Making
			LAMMPS</A> section for more info. This is
			because some machines may not support the low-level XDR data format
			that XTC files are written with, which will result in a compile-time
			error when a low-level include file is not found. Putting this style
			in a package makes it easy to exclude from a LAMMPS build for those
			machines. However, the XTC package also includes two compatibility
			header files and associated functions, which should be a suitable
			substitute on machines that do not have the appropriate native header
			files. This option can be invoked at build time by adding
			-DLAMMPS_XDR to the CCFLAGS variable in the appropriate low-level
			Makefile, e.g. src/MAKE/Makefile.foo. This compatibility mode has
			been tested successfully on Cray XT3/XT4/XT5 and IBM BlueGene/L
			machines and should also work on IBM BG/P, and Windows XP/Vista/7
			machines.
			</P>
			<P><B>Related commands:</B>
			</P>
			<P><A HREF = "dump_h5md.html">dump h5md</A>, <A HREF = "dump_image.html">dump image</A>,
			<A HREF = "dump_molfile.html">dump molfile</A>, <A HREF = "dump_modify.html">dump_modify</A>,
			<A HREF = "undump.html">undump</A>
			</P>
			<P><B>Default:</B>
			</P>
			<P>The defaults for the <I>image</I> and <I>movie</I> styles are listed on the
			<A HREF = "dump_image.html">dump image</A> doc page.
			</P>
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