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

<LI>style = <I>atom</I> or <I>bond</I> or <I>cfg</I> or <I>dcd</I> or <I>xtc</I> or <I>xyz</I> or <I>custom</I> 

<LI>style = <I>atom</I> or <I>cfg</I> or <I>dcd</I> or <I>xtc</I> or <I>xyz</I> or <I>local</I> or <I>custom</I> 

<LI>N = dump every this many timesteps 

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

<PRE>  <I>atom</I> args = none

  <I>bond</I> args = none

  <I>cfg</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 

  <I>custom</I> args = list of atom attributes

</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> args = list of atom attributes

    possible attributes = id, mol, type, mass,

			  x, y, z, xs, ys, zs, xu, yu, zu, ix, iy, iz,

			  vx, vy, vz, fx, fy, fz,

      angmomx,angmomy,angmomz = angular momentum of extended particle

      quatw,quati,quatj,quatk = quaternion components for aspherical particles

      tqx,tqy,tqz = torque on extended particles

      c_ID = per-atom vector value calculated by a compute with ID

      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 value calculated by a fix 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 

</PRE>

dump files (typically one line per atom) may be written in an

indeterminate order.  This is because data for a single snapshot is

collected from multiple processors.  This is always the case for the

<I>atom</I>, <I>bond</I>, and <I>custom</I> styles.  It is also the case for the

<I>atom</I>, <I>local</I>, and <I>custom</I> styles.  It is also the case for the

<I>xyz</I> style if the dump group is not <I>all</I>.  It is not the case for

the <I>dcd</I> and <I>xtc</I> styles which always write atoms in sorted order.

So does the <I>xyz</I> style if the dump group is <I>all</I>.  The <I>cfg</I> style

<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>bond</I>, and <I>custom</I> styles create files in a simple text

<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.cs.sandia.gov/~sjplimp/pizza.html">Pizza.py</A>, work with

<A HREF = "dump_modify.html">dump_modify</A> settings.  Image flags can also be

added for each atom via dump_modify.

</P>

<P>For style <I>bond</I>, the bond topology between atoms is written, in the

same format specified in data files read in by the

<A HREF = "read_data.html">read_data</A> command.  Both atoms in the bond must be in

the dump group for the bond to be written.  Any bonds that have been

broken (see the <A HREF = "bond_style.html">bond_style</A> command) by setting their

bond type to 0 are not written.  Bonds that have been turned off (see

the <A HREF = "fix_shake.html">fix shake</A> or <A HREF = "delete_bonds.html">delete_bonds</A>

commands) by setting their bond type negative are written into the

file.

</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

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 dump custom quantities is given

below.

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 gnerate 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

</P>

<HR>

<P>This section explains the atom quantities that can be specified as

<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>

<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>type</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> keywords are self-explanatory.

<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>Type</I> is the atom type.  <I>Mass</I> is the

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> keywords write atom coordinates "unscaled", in the

<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 simluation box is triclinic

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.  The image flags can be printed directly using the <I>ix</I>,

<I>iy</I>, <I>iz</I> keywords. The <A HREF = "dump_modify.html">dump_modify</A> command

<I>iy</I>, <I>iz</I> attributes. The <A HREF = "dump_modify.html">dump_modify</A> command

describes in more detail what is meant by scaled vs unscaled

coordinates and the image flags.

</P>

<P>The <I>mux</I>, <I>muy</I>, <I>muz</I> keywords are specific to dipolar systems

<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.

</P>

<P>The <I>radius</I> keyword is specific to extended spherical particles

<P>The <I>radius</I> attribute is specific to extended spherical particles

that have a finite size, such as granular particles defined with

an atom style of <I>granular</I>.

</P>

<P>The <I>omegax</I>, <I>omegay</I>, and <I>omegaz</I> keywords are specific to extended

<P>The <I>omegax</I>, <I>omegay</I>, and <I>omegaz</I> attributes are specific to extended

spherical or aspherical particles that have an angular velocity.  Only

certain atom styles, such as <I>granular</I> or <I>dipole</I> define this

quantity.

</P>

<P>The <I>angmomx</I>, <I>angmomy</I>, and <I>angmomz</I> keywords are specific to

<P>The <I>angmomx</I>, <I>angmomy</I>, and <I>angmomz</I> attributes are specific to

extended aspherical particles that have an angular momentum.  Only

the <I>ellipsoid</I> atom style defines this quantity.

</P>

<P>The <I>quatw</I>, <I>quati</I>, <I>quatj</I>, <I>quatk</I> keywords are for aspherical

<P>The <I>quatw</I>, <I>quati</I>, <I>quatj</I>, <I>quatk</I> attributes are for aspherical

particles defined with an atom style of <I>ellipsoid</I>.  They are the

components of the quaternion that defines the orientation of the

particle.

</P>

<P>The <I>tqx</I>, <I>tqy</I>, <I>tqz</I> keywords are for extended spherical or

<P>The <I>tqx</I>, <I>tqy</I>, <I>tqz</I> attributes are for extended spherical or

aspherical 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> keywords allow scalar or vector per-atom

quantities calculated by a <A HREF = "compute.html">compute</A> to be output.  The

ID in the keyword 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 per-atom

computes for calculating the energy, stress, centro-symmetry

parameter, and coordination number of individual atoms.

</P>

<P>Note that computes which calculate global scalar and vector

quantities, as opposed to per-atom quantities, cannot be output in a

dump.  Instead, these quantities can be output by the <A HREF = "thermo_style.html">thermo_style

custom</A> command.

</P>

<P>If <I>c_ID</I> is used as a keyword, then the scalar per-atom quantity

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> keywords allow scalar or vector per-atom

<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

keyword should be replaced by the actual ID of the fix that has been

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

<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 keyword, then the scalar per-atom quantity

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> keyword allows per-atom quantities calculated by a

<A HREF = "variable.html">variable</A> to be output.  The name in the keyword 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>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>See <A HREF = "Section_modify.html">this section</A> of the manual for information

on how to add new compute and fix styles to LAMMPS to calculate

-DLAMMPS_GZIP option - see the <A HREF = "Section_start.html#2_2">Making LAMMPS</A>

section of the documentation.

</P>

<P>The <I>bond</I> style is part of the "molecular" package.  It is only

enabled if LAMMPS was built with that package.  See the <A HREF = "Section_start.html#2_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#2_3">Making

LAMMPS</A> section for more info.  This is because