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			<p class="caption"><span class="caption-text">User Documentation</span></p>
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			<li class="toctree-l1"><a class="reference internal" href="Section_intro.html">1. Introduction</a></li>
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			<li class="toctree-l1"><a class="reference internal" href="Section_modify.html">10. Modifying & extending LAMMPS</a></li>
			<li class="toctree-l1"><a class="reference internal" href="Section_python.html">11. Python interface to LAMMPS</a></li>
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			<p class="caption"><span class="caption-text">Index</span></p>
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			<li class="toctree-l2"><a class="reference internal" href="angle_coeff.html">angle_coeff command</a></li>
			<li class="toctree-l2"><a class="reference internal" href="angle_style.html">angle_style command</a></li>
			<li class="toctree-l2"><a class="reference internal" href="atom_modify.html">atom_modify command</a></li>
			<li class="toctree-l2"><a class="reference internal" href="atom_style.html">atom_style command</a></li>
			<li class="toctree-l2"><a class="reference internal" href="balance.html">balance command</a></li>
			<li class="toctree-l2"><a class="reference internal" href="bond_coeff.html">bond_coeff command</a></li>
			<li class="toctree-l2"><a class="reference internal" href="bond_style.html">bond_style command</a></li>
			<li class="toctree-l2"><a class="reference internal" href="bond_write.html">bond_write command</a></li>
			<li class="toctree-l2"><a class="reference internal" href="boundary.html">boundary command</a></li>
			<li class="toctree-l2"><a class="reference internal" href="box.html">box command</a></li>
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			<li class="toctree-l2"><a class="reference internal" href="clear.html">clear command</a></li>
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			<li class="toctree-l2"><a class="reference internal" href="compute.html">compute command</a></li>
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			<li class="toctree-l2"><a class="reference internal" href="delete_atoms.html">delete_atoms command</a></li>
			<li class="toctree-l2"><a class="reference internal" href="delete_bonds.html">delete_bonds command</a></li>
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			<li class="toctree-l2"><a class="reference internal" href="dimension.html">dimension command</a></li>
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			<li class="toctree-l2"><a class="reference internal" href="dump.html#dump-custom-vtk-command"><code class="docutils literal"><span class="pre">dump</span> <span class="pre">custom/vtk</span></code> command</a></li>
			<li class="toctree-l2"><a class="reference internal" href="dump.html#dump-h5md-command"><code class="docutils literal"><span class="pre">dump</span> <span class="pre">h5md</span></code> command</a></li>
			<li class="toctree-l2"><a class="reference internal" href="dump.html#dump-image-command"><code class="docutils literal"><span class="pre">dump</span> <span class="pre">image</span></code> command</a></li>
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			<li class="toctree-l2"><a class="reference internal" href="dump.html#dump-molfile-command"><code class="docutils literal"><span class="pre">dump</span> <span class="pre">molfile</span></code> command</a></li>
			<li class="toctree-l2"><a class="reference internal" href="dump_custom_vtk.html">dump custom/vtk command</a></li>
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			<li class="toctree-l2"><a class="reference internal" href="dump_modify.html">dump_modify command</a></li>
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			<li class="toctree-l2 current"><a class="current reference internal" href="#">read_data command</a><ul>
			<li class="toctree-l3"><a class="reference internal" href="#syntax">Syntax</a></li>
			<li class="toctree-l3"><a class="reference internal" href="#examples">Examples</a></li>
			<li class="toctree-l3"><a class="reference internal" href="#description">Description</a></li>
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			<div class="section" id="read-data-command">
			<span id="index-0"></span><h1>read_data command</h1>
			<div class="section" id="syntax">
			<h2>Syntax</h2>
			<pre class="literal-block">
			read_data file keyword args ...
			</pre>
			<ul>
			<li><p class="first">file = name of data file to read in</p>
			</li>
			<li><p class="first">zero or more keyword/arg pairs may be appended</p>
			</li>
			<li><p class="first">keyword = <em>add</em> or <em>offset</em> or <em>shift</em> or <em>extra/atom/types</em> or <em>extra/bond/types</em> or <em>extra/angle/types</em> or <em>extra/dihedral/types</em> or <em>extra/improper/types</em> or <em>group</em> or <em>nocoeff</em> or <em>fix</em></p>
			<pre class="literal-block">
			<em>add</em> arg = <em>append</em> or <em>Nstart</em> or <em>merge</em>
			append = add new atoms with IDs appended to current IDs
			Nstart = add new atoms with IDs starting with Nstart
			merge = add new atoms with their IDs unchanged
			<em>offset</em> args = toff boff aoff doff ioff
			toff = offset to add to atom types
			boff = offset to add to bond types
			aoff = offset to add to angle types
			doff = offset to add to dihedral types
			ioff = offset to add to improper types
			<em>shift</em> args = Sx Sy Sz
			Sx,Sy,Sz = distance to shift atoms when adding to system (distance units)
			<em>extra/atom/types</em> arg = # of extra atom types
			<em>extra/bond/types</em> arg = # of extra bond types
			<em>extra/angle/types</em> arg = # of extra angle types
			<em>extra/dihedral/types</em> arg = # of extra dihedral types
			<em>extra/improper/types</em> arg = # of extra improper types
			<em>group</em> args = groupID
			groupID = add atoms in data file to this group
			<em>nocoeff</em> = ignore force field parameters
			<em>fix</em> args = fix-ID header-string section-string
			fix-ID = ID of fix to process header lines and sections of data file
			header-string = header lines containing this string will be passed to fix
			section-string = section names with this string will be passed to fix
			</pre>
			</li>
			</ul>
			</div>
			<div class="section" id="examples">
			<h2>Examples</h2>
			<pre class="literal-block">
			read_data data.lj
			read_data ../run7/data.polymer.gz
			read_data data.protein fix mycmap crossterm CMAP
			read_data data.water add append offset 3 1 1 1 1 shift 0.0 0.0 50.0
			read_data data.water add merge 1 group solvent
			</pre>
			</div>
			<div class="section" id="description">
			<h2>Description</h2>
			<p>Read in a data file containing information LAMMPS needs to run a
			simulation. The file can be ASCII text or a gzipped text file
			(detected by a .gz suffix). This is one of 3 ways to specify initial
			atom coordinates; see the <a class="reference internal" href="read_restart.html"><span class="doc">read_restart</span></a> and
			<a class="reference internal" href="create_atoms.html"><span class="doc">create_atoms</span></a> commands for alternative methods.
			Also see the explanation of the <a class="reference internal" href="Section_start.html#start-7"><span class="std std-ref">-restart command-line switch</span></a> which can convert a restart file to
			a data file.</p>
			<p>This command can be used multiple times to add new atoms and their
			properties to an existing system by using the <em>add</em>, <em>offset</em>, and
			<em>shift</em> keywords. See more details below, which includes the use case
			for the <em>extra</em> keywords.</p>
			<p>The <em>group</em> keyword adds all the atoms in the data file to the
			specified group-ID. The group will be created if it does not already
			exist. This is useful if you are reading multiple data files and wish
			to put sets of atoms into different groups so they can be operated on
			later. E.g. a group of added atoms can be moved to new positions via
			the <a class="reference internal" href="displace_atoms.html"><span class="doc">displace_atoms</span></a> command. Note that atoms
			read from the data file are also always added to the “all” group. The
			<a class="reference internal" href="group.html"><span class="doc">group</span></a> command discusses atom groups, as used in LAMMPS.</p>
			<p>The <em>nocoeff</em> keyword tells read_data to ignore force field parameters.
			The various Coeff sections are still read and have to have the correct
			number of lines, but they are not applied. This also allows to read a
			data file without having any pair, bond, angle, dihedral or improper
			styles defined, or to read a data file for a different force field.</p>
			<p>The use of the <em>fix</em> keyword is discussed below.</p>
			<hr class="docutils" />
			<p><strong>Reading multiple data files</strong></p>
			<p>The read_data command can be used multiple times with the same or
			different data files to build up a complex system from components
			contained in individual data files. For example one data file could
			contain fluid in a confined domain; a second could contain wall atoms,
			and the second file could be read a third time to create a wall on the
			other side of the fluid. The third set of atoms could be rotated to
			an opposing direction using the <a class="reference internal" href="displace_atoms.html"><span class="doc">displace_atoms</span></a>
			command, after the third read_data command is used.</p>
			<p>The <em>add</em>, <em>offset</em>, <em>shift</em>, <em>extra</em>, and <em>group</em> keywords are
			useful in this context.</p>
			<p>If a simulation box does not yet exist, the <em>add</em> keyword
			cannot be used; the read_data command is being used for the first
			time. If a simulation box does exist, due to using the
			<a class="reference internal" href="create_box.html"><span class="doc">create_box</span></a> command, or a previous read_data command,
			then the <em>add</em> keyword must be used.</p>
			<div class="admonition note">
			<p class="first admonition-title">Note</p>
			<p class="last">The simulation box size (xlo to xhi, ylo to yhi, zlo to zhi) in
			the new data file will be merged with the existing simulation box to
			create a large enough box in each dimension to contain both the
			existing and new atoms. Each box dimension never shrinks due to this
			merge operation, it only stays the same or grows. Care must be used if
			you are growing the existing simulation box in a periodic dimension.
			If there are existing atoms with bonds that straddle that periodic
			boundary, then the atoms may become far apart if the box size grows.
			This will separate the atoms in the bond, which can lead to “lost”
			bond atoms or bad dynamics.</p>
			</div>
			<p>The three choices for the <em>add</em> argument affect how the IDs of atoms
			in the data file are treated. If <em>append</em> is specified, atoms in the
			data file are added to the current system, with their atom IDs reset
			so that an atomID = M in the data file becomes atomID = N+M, where N
			is the largest atom ID in the current system. This rule is applied to
			all occurrences of atom IDs in the data file, e.g. in the Velocity or
			Bonds section. If <em>Nstart</em> is specified, then <em>Nstart</em> is a numeric
			value is given, e.g. 1000, so that an atomID = M in the data file
			becomes atomID = 1000+M. If <em>merge</em> is specified, the data file atoms
			are added to the current system without changing their IDs. They are
			assumed to merge (without duplication) with the currently defined
			atoms. It is up to you to insure there are no multiply defined atom
			IDs, as LAMMPS only performs an incomplete check that this is the case
			by insuring the resulting max atomID >= the number of atoms.</p>
			<p>The <em>offset</em> and <em>shift</em> keywords can only be used if the <em>add</em>
			keyword is also specified.</p>
			<p>The <em>offset</em> keyword adds the specified offset values to the atom
			types, bond types, angle types, dihedral types, and improper types as
			they are read from the data file. E.g. if <em>toff</em> = 2, and the file
			uses atom types 1,2,3, then the added atoms will have atom types
			3,4,5. These offsets apply to all occurrences of types in the data
			file, e.g. for the Atoms or Masses or Pair Coeffs or Bond Coeffs
			sections. This makes it easy to use atoms and molecules and their
			attributes from a data file in different simulations, where you want
			their types (atom, bond, angle, etc) to be different depending on what
			other types already exist. All five offset values must be specified,
			but individual values will be ignored if the data file does not use
			that attribute (e.g. no bonds).</p>
			<p>The <em>shift</em> keyword can be used to specify an (Sx, Sy, Sz)
			displacement applied to the coordinates of each atom. Sz must be 0.0
			for a 2d simulation. This is a mechanism for adding structured
			collections of atoms at different locations within the simulation box,
			to build up a complex geometry. It is up to you to insure atoms do
			not end up overlapping unphysically which would lead to bad dynamics.
			Note that the <a class="reference internal" href="displace_atoms.html"><span class="doc">displace_atoms</span></a> command can be used
			to move a subset of atoms after they have been read from a data file.
			Likewise, the <a class="reference internal" href="delete_atoms.html"><span class="doc">delete_atoms</span></a> command can be used to
			remove overlapping atoms. Note that the shift values (Sx, Sy, Sz) are
			also added to the simulation box information (xlo, xhi, ylo, yhi, zlo,
			zhi) in the data file to shift its boundaries. E.g. xlo_new = xlo +
			Sx, xhi_new = xhi + Sx.</p>
			<p>The <em>extra</em> keywords can only be used the first time the read_data
			command is used. They are useful if you intend to add new atom, bond,
			angle, etc types later with additional read_data commands. This is
			because the maximum number of allowed atom, bond, angle, etc types is
			set by LAMMPS when the system is first initialized. If you do not use
			the <em>extra</em> keywords, then the number of these types will be limited
			to what appears in the first data file you read. For example, if the
			first data file is a solid substrate of Si, it will likely specify a
			single atom type. If you read a second data file with a different
			material (water molecules) that sit on top of the substrate, you will
			want to use different atom types for those atoms. You can only do
			this if you set the <em>extra/atom/types</em> keyword to a sufficiently large
			value when reading the substrate data file. Note that use of the
			<em>extra</em> keywords also allows each data file to contain sections like
			Masses or Pair Coeffs or Bond Coeffs which are sized appropriately for
			the number of types in that data file. If the <em>offset</em> keyword is
			used appropriately when each data file is read, the values in those
			sections will be stored correctly in the larger data structures
			allocated by the use of the <em>extra</em> keywords. E.g. the substrate file
			can list mass and pair coefficients for type 1 silicon atoms. The
			water file can list mass and pair coeffcients for type 1 and type 2
			hydrogen and oxygen atoms. Use of the <em>extra</em> and <em>offset</em> keywords
			will store those mass and pair coefficient values appropriately in
			data structures that allow for 3 atom types (Si, H, O). Of course,
			you would still need to specify coefficients for H/Si and O/Si
			interactions in your input script to have a complete pairwise
			interaction model.</p>
			<p>An alternative to using the <em>extra</em> keywords with the read_data
			command, is to use the <a class="reference internal" href="create_box.html"><span class="doc">create_box</span></a> command to
			initialize the simulation box and all the various type limits you need
			via its <em>extra</em> keywords. Then use the read_data command one or more
			times to populate the system with atoms, bonds, angles, etc, using the
			<em>offset</em> keyword if desired to alter types used in the various data
			files you read.</p>
			<hr class="docutils" />
			<p><strong>Format of a data file</strong></p>
			<p>The structure of the data file is important, though many settings and
			sections are optional or can come in any order. See the examples
			directory for sample data files for different problems.</p>
			<p>A data file has a header and a body. The header appears first. The
			first line of the header is always skipped; it typically contains a
			description of the file. Then lines are read one at a time. Lines
			can have a trailing comment starting with ‘#’ that is ignored. If the
			line is blank (only whitespace after comment is deleted), it is
			skipped. If the line contains a header keyword, the corresponding
			value(s) is read from the line. If it doesn’t contain a header
			keyword, the line begins the body of the file.</p>
			<p>The body of the file contains zero or more sections. The first line
			of a section has only a keyword. This line can have a trailing
			comment starting with ‘#’ that is either ignored or can be used to
			check for a style match, as described below. The next line is
			skipped. The remaining lines of the section contain values. The
			number of lines depends on the section keyword as described below.
			Zero or more blank lines can be used between sections. Sections can
			appear in any order, with a few exceptions as noted below.</p>
			<p>The keyword <em>fix</em> can be used one or more times. Each usage specifies
			a fix that will be used to process a specific portion of the data
			file. Any header line containing <em>header-string</em> and any section with
			a name containing <em>section-string</em> will be passed to the specified
			fix. See the <a class="reference internal" href="fix_property_atom.html"><span class="doc">fix property/atom</span></a> command for
			an example of a fix that operates in this manner. The doc page for
			the fix defines the syntax of the header line(s) and section(s) that
			it reads from the data file. Note that the <em>header-string</em> can be
			specified as NULL, in which case no header lines are passed to the
			fix. This means that it can infer the length of its Section from
			standard header settings, such as the number of atoms.</p>
			<p>The formatting of individual lines in the data file (indentation,
			spacing between words and numbers) is not important except that header
			and section keywords (e.g. atoms, xlo xhi, Masses, Bond Coeffs) must
			be capitalized as shown and can’t have extra white space between their
			words - e.g. two spaces or a tab between the 2 words in “xlo xhi” or
			the 2 words in “Bond Coeffs”, is not valid.</p>
			<hr class="docutils" />
			<p><strong>Format of the header of a data file</strong></p>
			<p>These are the recognized header keywords. Header lines can come in
			any order. The value(s) are read from the beginning of the line.
			Thus the keyword <em>atoms</em> should be in a line like “1000 atoms”; the
			keyword <em>ylo yhi</em> should be in a line like “-10.0 10.0 ylo yhi”; the
			keyword <em>xy xz yz</em> should be in a line like “0.0 5.0 6.0 xy xz yz”.
			All these settings have a default value of 0, except the lo/hi box
			size defaults are -0.5 and 0.5. A line need only appear if the value
			is different than the default.</p>
			<ul class="simple">
			<li><em>atoms</em> = # of atoms in system</li>
			<li><em>bonds</em> = # of bonds in system</li>
			<li><em>angles</em> = # of angles in system</li>
			<li><em>dihedrals</em> = # of dihedrals in system</li>
			<li><em>impropers</em> = # of impropers in system</li>
			<li><em>atom types</em> = # of atom types in system</li>
			<li><em>bond types</em> = # of bond types in system</li>
			<li><em>angle types</em> = # of angle types in system</li>
			<li><em>dihedral types</em> = # of dihedral types in system</li>
			<li><em>improper types</em> = # of improper types in system</li>
			<li><em>extra bond per atom</em> = leave space for this many new bonds per atom</li>
			<li><em>extra angle per atom</em> = leave space for this many new angles per atom</li>
			<li><em>extra dihedral per atom</em> = leave space for this many new dihedrals per atom</li>
			<li><em>extra improper per atom</em> = leave space for this many new impropers per atom</li>
			<li><em>extra special per atom</em> = leave space for this many new special bonds per atom</li>
			<li><em>ellipsoids</em> = # of ellipsoids in system</li>
			<li><em>lines</em> = # of line segments in system</li>
			<li><em>triangles</em> = # of triangles in system</li>
			<li><em>bodies</em> = # of bodies in system</li>
			<li><em>xlo xhi</em> = simulation box boundaries in x dimension</li>
			<li><em>ylo yhi</em> = simulation box boundaries in y dimension</li>
			<li><em>zlo zhi</em> = simulation box boundaries in z dimension</li>
			<li><em>xy xz yz</em> = simulation box tilt factors for triclinic system</li>
			</ul>
			<p>The initial simulation box size is determined by the lo/hi settings.
			In any dimension, the system may be periodic or non-periodic; see the
			<a class="reference internal" href="boundary.html"><span class="doc">boundary</span></a> command. When the simulation box is created
			it is also partitioned into a regular 3d grid of rectangular bricks,
			one per processor, based on the number of processors being used and
			the settings of the <a class="reference internal" href="processors.html"><span class="doc">processors</span></a> command. The
			partitioning can later be changed by the <a class="reference internal" href="balance.html"><span class="doc">balance</span></a> or
			<a class="reference internal" href="fix_balance.html"><span class="doc">fix balance</span></a> commands.</p>
			<p>If the <em>xy xz yz</em> line does not appear, LAMMPS will set up an
			axis-aligned (orthogonal) simulation box. If the line does appear,
			LAMMPS creates a non-orthogonal simulation domain shaped as a
			parallelepiped with triclinic symmetry. The parallelepiped has its
			“origin” at (xlo,ylo,zlo) and is defined by 3 edge vectors starting
			from the origin given by A = (xhi-xlo,0,0); B = (xy,yhi-ylo,0); C =
			(xz,yz,zhi-zlo). <em>Xy,xz,yz</em> can be 0.0 or positive or negative values
			and are called “tilt factors” because they are the amount of
			displacement applied to faces of an originally orthogonal box to
			transform it into the parallelepiped.</p>
			<p>By default, the tilt factors (xy,xz,yz) can not skew the box more than
			half the distance of the corresponding parallel box length. For
			example, if xlo = 2 and xhi = 12, then the x box length is 10 and the
			xy tilt factor must be between -5 and 5. Similarly, both xz and yz
			must be between -(xhi-xlo)/2 and +(yhi-ylo)/2. Note that this is not
			a limitation, since if the maximum tilt factor is 5 (as in this
			example), then configurations with tilt = ..., -15, -5, 5, 15, 25,
			... are all geometrically equivalent. If you wish to define a box
			with tilt factors that exceed these limits, you can use the <a class="reference internal" href="box.html"><span class="doc">box tilt</span></a> command, with a setting of <em>large</em>; a setting of
			<em>small</em> is the default.</p>
			<p>See <a class="reference internal" href="Section_howto.html#howto-12"><span class="std std-ref">Section 6.12</span></a> of the doc pages
			for a geometric description of triclinic boxes, as defined by LAMMPS,
			and how to transform these parameters to and from other commonly used
			triclinic representations.</p>
			<p>When a triclinic system is used, the simulation domain should normally
			be periodic in the dimension that the tilt is applied to, which is
			given by the second dimension of the tilt factor (e.g. y for xy tilt).
			This is so that pairs of atoms interacting across that boundary will
			have one of them shifted by the tilt factor. Periodicity is set by
			the <a class="reference internal" href="boundary.html"><span class="doc">boundary</span></a> command. For example, if the xy tilt
			factor is non-zero, then the y dimension should be periodic.
			Similarly, the z dimension should be periodic if xz or yz is non-zero.
			LAMMPS does not require this periodicity, but you may lose atoms if
			this is not the case.</p>
			<p>Also note that if your simulation will tilt the box, e.g. via the <a class="reference internal" href="fix_deform.html"><span class="doc">fix deform</span></a> command, the simulation box must be setup to
			be triclinic, even if the tilt factors are initially 0.0. You can
			also change an orthogonal box to a triclinic box or vice versa by
			using the <a class="reference internal" href="change_box.html"><span class="doc">change box</span></a> command with its <em>ortho</em> and
			<em>triclinic</em> options.</p>
			<p>For 2d simulations, the <em>zlo zhi</em> values should be set to bound the z
			coords for atoms that appear in the file; the default of -0.5 0.5 is
			valid if all z coords are 0.0. For 2d triclinic simulations, the xz
			and yz tilt factors must be 0.0.</p>
			<p>If the system is periodic (in a dimension), then atom coordinates can
			be outside the bounds (in that dimension); they will be remapped (in a
			periodic sense) back inside the box. Note that if the <em>add</em> option is
			being used to add atoms to a simulation box that already exists, this
			periodic remapping will be performed using simulation box bounds that
			are the union of the existing box and the box boundaries in the new
			data file.</p>
			<div class="admonition note">
			<p class="first admonition-title">Note</p>
			<p class="last">If the system is non-periodic (in a dimension), then all atoms
			in the data file must have coordinates (in that dimension) that are
			“greater than or equal to” the lo value and “less than or equal to”
			the hi value. If the non-periodic dimension is of style “fixed” (see
			the <a class="reference internal" href="boundary.html"><span class="doc">boundary</span></a> command), then the atom coords must be
			strictly “less than” the hi value, due to the way LAMMPS assign atoms
			to processors. Note that you should not make the lo/hi values
			radically smaller/larger than the extent of the atoms. For example,
			if your atoms extend from 0 to 50, you should not specify the box
			bounds as -10000 and 10000. This is because LAMMPS uses the specified
			box size to layout the 3d grid of processors. A huge (mostly empty)
			box will be sub-optimal for performance when using “fixed” boundary
			conditions (see the <a class="reference internal" href="boundary.html"><span class="doc">boundary</span></a> command). When using
			“shrink-wrap” boundary conditions (see the <a class="reference internal" href="boundary.html"><span class="doc">boundary</span></a>
			command), a huge (mostly empty) box may cause a parallel simulation to
			lose atoms when LAMMPS shrink-wraps the box around the atoms. The
			read_data command will generate an error in this case.</p>
			</div>
			<p>The “extra bond per atom” setting (angle, dihedral, improper) is only
			needed if new bonds (angles, dihedrals, impropers) will be added to
			the system when a simulation runs, e.g. by using the <a class="reference internal" href="fix_bond_create.html"><span class="doc">fix bond/create</span></a> command. This will pre-allocate
			space in LAMMPS data structures for storing the new bonds (angles,
			dihedrals, impropers).</p>
			<p>The “extra special per atom” setting is typically only needed if new
			bonds/angles/etc will be added to the system, e.g. by using the <a class="reference internal" href="fix_bond_create.html"><span class="doc">fix bond/create</span></a> command. Or if entire new molecules
			will be added to the system, e.g. by using the <a class="reference internal" href="fix_deposit.html"><span class="doc">fix deposit</span></a> or <a class="reference internal" href="fix_pour.html"><span class="doc">fix pour</span></a> commands, which
			will have more special 1-2,1-3,1-4 neighbors than any other molecules
			defined in the data file. Using this setting will pre-allocate space
			in the LAMMPS data structures for storing these neighbors. See the
			<a class="reference internal" href="special_bonds.html"><span class="doc">special_bonds</span></a> and <a class="reference internal" href="molecule.html"><span class="doc">molecule</span></a> doc
			pages for more discussion of 1-2,1-3,1-4 neighbors.</p>
			<div class="admonition note">
			<p class="first admonition-title">Note</p>
			<p class="last">All of the “extra” settings are only used if they appear in the
			first data file read; see the description of the <em>add</em> keyword above
			for reading multiple data files. If they appear in later data files,
			they are ignored.</p>
			</div>
			<p>The “ellipsoids” and “lines” and “triangles” and “bodies” settings are
			only used with <a class="reference internal" href="atom_style.html"><span class="doc">atom_style ellipsoid or line or tri or body</span></a> and specify how many of the atoms are
			finite-size ellipsoids or lines or triangles or bodies; the remainder
			are point particles. See the discussion of ellipsoidflag and the
			<em>Ellipsoids</em> section below. See the discussion of lineflag and the
			<em>Lines</em> section below. See the discussion of triangleflag and the
			<em>Triangles</em> section below. See the discussion of bodyflag and the
			<em>Bodies</em> section below.</p>
			<div class="admonition note">
			<p class="first admonition-title">Note</p>
			<p class="last">For <a class="reference internal" href="atom_style.html"><span class="doc">atom_style template</span></a>, the molecular
			topology (bonds,angles,etc) is contained in the molecule templates
			read-in by the <a class="reference internal" href="molecule.html"><span class="doc">molecule</span></a> command. This means you
			cannot set the <em>bonds</em>, <em>angles</em>, etc header keywords in the data
			file, nor can you define <em>Bonds</em>, <em>Angles</em>, etc sections as discussed
			below. You can set the <em>bond types</em>, <em>angle types</em>, etc header
			keywords, though it is not necessary. If specified, they must match
			the maximum values defined in any of the template molecules.</p>
			</div>
			<hr class="docutils" />
			<p><strong>Format of the body of a data file</strong></p>
			<p>These are the section keywords for the body of the file.</p>
			<ul class="simple">
			<li><em>Atoms, Velocities, Masses, Ellipsoids, Lines, Triangles, Bodies</em> = atom-property sections</li>
			<li><em>Bonds, Angles, Dihedrals, Impropers</em> = molecular topology sections</li>
			<li><em>Pair Coeffs, PairIJ Coeffs, Bond Coeffs, Angle Coeffs, Dihedral Coeffs, Improper Coeffs</em> = force field sections</li>
			<li><em>BondBond Coeffs, BondAngle Coeffs, MiddleBondTorsion Coeffs, EndBondTorsion Coeffs, AngleTorsion Coeffs, AngleAngleTorsion Coeffs, BondBond13 Coeffs, AngleAngle Coeffs</em> = class 2 force field sections</li>
			</ul>
			<p>These keywords will check an appended comment for a match with the
			currently defined style:</p>
			<ul class="simple">
			<li><em>Atoms, Pair Coeffs, PairIJ Coeffs, Bond Coeffs, Angle Coeffs, Dihedral Coeffs, Improper Coeffs</em></li>
			</ul>
			<p>For example, these lines:</p>
			<div class="highlight-default"><div class="highlight"><pre><span></span><span class="n">Atoms</span> <span class="c1"># sphere</span>
			<span class="n">Pair</span> <span class="n">Coeffs</span> <span class="c1"># lj/cut</span>
			</pre></div>
			</div>
			<p>will check if the currently-defined <a class="reference internal" href="atom_style.html"><span class="doc">atom_style</span></a> is
			<em>sphere</em>, and the current <a class="reference external" href="pair_style">pair_style</a> is <em>lj/cut</em>. If
			not, LAMMPS will issue a warning to indicate that the data file
			section likely does not contain the correct number or type of
			parameters expected for the currently-defined style.</p>
			<p>Each section is listed below in alphabetic order. The format of each
			section is described including the number of lines it must contain and
			rules (if any) for where it can appear in the data file.</p>
			<p>Any individual line in the various sections can have a trailing
			comment starting with “#” for annotation purposes. E.g. in the
			Atoms section:</p>
			<div class="highlight-default"><div class="highlight"><pre><span></span><span class="mi">10</span> <span class="mi">1</span> <span class="mi">17</span> <span class="o">-</span><span class="mf">1.0</span> <span class="mf">10.0</span> <span class="mf">5.0</span> <span class="mf">6.0</span> <span class="c1"># salt ion</span>
			</pre></div>
			</div>
			<hr class="docutils" />
			<p><em>Angle Coeffs</em> section:</p>
			<ul>
			<li><p class="first">one line per angle type</p>
			</li>
			<li><p class="first">line syntax: ID coeffs</p>
			<div class="highlight-default"><div class="highlight"><pre><span></span><span class="n">ID</span> <span class="o">=</span> <span class="n">angle</span> <span class="nb">type</span> <span class="p">(</span><span class="mi">1</span><span class="o">-</span><span class="n">N</span><span class="p">)</span>
			<span class="n">coeffs</span> <span class="o">=</span> <span class="nb">list</span> <span class="n">of</span> <span class="n">coeffs</span>
			</pre></div>
			</div>
			</li>
			<li><p class="first">example:</p>
			<div class="highlight-default"><div class="highlight"><pre><span></span><span class="mi">6</span> <span class="mi">70</span> <span class="mf">108.5</span> <span class="mi">0</span> <span class="mi">0</span>
			</pre></div>
			</div>
			</li>
			</ul>
			<p>The number and meaning of the coefficients are specific to the defined
			angle style. See the <a class="reference internal" href="angle_style.html"><span class="doc">angle_style</span></a> and
			<a class="reference internal" href="angle_coeff.html"><span class="doc">angle_coeff</span></a> commands for details. Coefficients can
			also be set via the <a class="reference internal" href="angle_coeff.html"><span class="doc">angle_coeff</span></a> command in the
			input script.</p>
			<hr class="docutils" />
			<p><em>AngleAngle Coeffs</em> section:</p>
			<ul>
			<li><p class="first">one line per improper type</p>
			</li>
			<li><p class="first">line syntax: ID coeffs</p>
			<pre class="literal-block">
			ID = improper type (1-N)
			coeffs = list of coeffs (see <a class="reference internal" href="improper_coeff.html"><span class="doc">improper_coeff</span></a>)
			</pre>
			</li>
			</ul>
			<hr class="docutils" />
			<p><em>AngleAngleTorsion Coeffs</em> section:</p>
			<ul>
			<li><p class="first">one line per dihedral type</p>
			</li>
			<li><p class="first">line syntax: ID coeffs</p>
			<pre class="literal-block">
			ID = dihedral type (1-N)
			coeffs = list of coeffs (see <a class="reference internal" href="dihedral_coeff.html"><span class="doc">dihedral_coeff</span></a>)
			</pre>
			</li>
			</ul>
			<hr class="docutils" />
			<p><em>Angles</em> section:</p>
			<ul>
			<li><p class="first">one line per angle</p>
			</li>
			<li><p class="first">line syntax: ID type atom1 atom2 atom3</p>
			<div class="highlight-default"><div class="highlight"><pre><span></span><span class="n">ID</span> <span class="o">=</span> <span class="n">number</span> <span class="n">of</span> <span class="n">angle</span> <span class="p">(</span><span class="mi">1</span><span class="o">-</span><span class="n">Nangles</span><span class="p">)</span>
			<span class="nb">type</span> <span class="o">=</span> <span class="n">angle</span> <span class="nb">type</span> <span class="p">(</span><span class="mi">1</span><span class="o">-</span><span class="n">Nangletype</span><span class="p">)</span>
			<span class="n">atom1</span><span class="p">,</span><span class="n">atom2</span><span class="p">,</span><span class="n">atom3</span> <span class="o">=</span> <span class="n">IDs</span> <span class="n">of</span> <span class="mi">1</span><span class="n">st</span><span class="p">,</span><span class="mi">2</span><span class="n">nd</span><span class="p">,</span><span class="mi">3</span><span class="n">rd</span> <span class="n">atoms</span> <span class="ow">in</span> <span class="n">angle</span>
			</pre></div>
			</div>
			</li>
			</ul>
			<p>example:</p>
			<blockquote>
			<div><div class="highlight-default"><div class="highlight"><pre><span></span><span class="mi">2</span> <span class="mi">2</span> <span class="mi">17</span> <span class="mi">29</span> <span class="mi">430</span>
			</pre></div>
			</div>
			</div></blockquote>
			<p>The 3 atoms are ordered linearly within the angle. Thus the central
			atom (around which the angle is computed) is the atom2 in the list.
			E.g. H,O,H for a water molecule. The <em>Angles</em> section must appear
			after the <em>Atoms</em> section. All values in this section must be
			integers (1, not 1.0).</p>
			<hr class="docutils" />
			<p><em>AngleTorsion Coeffs</em> section:</p>
			<ul>
			<li><p class="first">one line per dihedral type</p>
			</li>
			<li><p class="first">line syntax: ID coeffs</p>
			<pre class="literal-block">
			ID = dihedral type (1-N)
			coeffs = list of coeffs (see <a class="reference internal" href="dihedral_coeff.html"><span class="doc">dihedral_coeff</span></a>)
			</pre>
			</li>
			</ul>
			<hr class="docutils" />
			<p><em>Atoms</em> section:</p>
			<ul class="simple">
			<li>one line per atom</li>
			<li>line syntax: depends on atom style</li>
			</ul>
			<p>An <em>Atoms</em> section must appear in the data file if natoms > 0 in the
			header section. The atoms can be listed in any order. These are the
			line formats for each <a class="reference internal" href="atom_style.html"><span class="doc">atom style</span></a> in LAMMPS. As
			discussed below, each line can optionally have 3 flags (nx,ny,nz)
			appended to it, which indicate which image of a periodic simulation
			box the atom is in. These may be important to include for some kinds
			of analysis.</p>
			<table border="1" class="docutils">
			<colgroup>
			<col width="14%" />
			<col width="86%" />
			</colgroup>
			<tbody valign="top">
			<tr class="row-odd"><td>angle</td>
			<td>atom-ID molecule-ID atom-type x y z</td>
			</tr>
			<tr class="row-even"><td>atomic</td>
			<td>atom-ID atom-type x y z</td>
			</tr>
			<tr class="row-odd"><td>body</td>
			<td>atom-ID atom-type bodyflag mass x y z</td>
			</tr>
			<tr class="row-even"><td>bond</td>
			<td>atom-ID molecule-ID atom-type x y z</td>
			</tr>
			<tr class="row-odd"><td>charge</td>
			<td>atom-ID atom-type q x y z</td>
			</tr>
			<tr class="row-even"><td>dipole</td>
			<td>atom-ID atom-type q x y z mux muy muz</td>
			</tr>
			<tr class="row-odd"><td>dpd</td>
			<td>atom-ID atom-type theta x y z</td>
			</tr>
			<tr class="row-even"><td>electron</td>
			<td>atom-ID atom-type q spin eradius x y z</td>
			</tr>
			<tr class="row-odd"><td>ellipsoid</td>
			<td>atom-ID atom-type ellipsoidflag density x y z</td>
			</tr>
			<tr class="row-even"><td>full</td>
			<td>atom-ID molecule-ID atom-type q x y z</td>
			</tr>
			<tr class="row-odd"><td>line</td>
			<td>atom-ID molecule-ID atom-type lineflag density x y z</td>
			</tr>
			<tr class="row-even"><td>meso</td>
			<td>atom-ID atom-type rho e cv x y z</td>
			</tr>
			<tr class="row-odd"><td>molecular</td>
			<td>atom-ID molecule-ID atom-type x y z</td>
			</tr>
			<tr class="row-even"><td>peri</td>
			<td>atom-ID atom-type volume density x y z</td>
			</tr>
			<tr class="row-odd"><td>smd</td>
			<td>atom-ID atom-type molecule volume mass kernel-radius contact-radius x y z</td>
			</tr>
			<tr class="row-even"><td>sphere</td>
			<td>atom-ID atom-type diameter density x y z</td>
			</tr>
			<tr class="row-odd"><td>template</td>
			<td>atom-ID molecule-ID template-index template-atom atom-type x y z</td>
			</tr>
			<tr class="row-even"><td>tri</td>
			<td>atom-ID molecule-ID atom-type triangleflag density x y z</td>
			</tr>
			<tr class="row-odd"><td>wavepacket</td>
			<td>atom-ID atom-type charge spin eradius etag cs_re cs_im x y z</td>
			</tr>
			<tr class="row-even"><td>hybrid</td>
			<td>atom-ID atom-type x y z sub-style1 sub-style2 ...</td>
			</tr>
			</tbody>
			</table>
			<p>The per-atom values have these meanings and units, listed alphabetically:</p>
			<ul class="simple">
			<li>atom-ID = integer ID of atom</li>
			<li>atom-type = type of atom (1-Ntype)</li>
			<li>bodyflag = 1 for body particles, 0 for point particles</li>
			<li>contact-radius = ??? (distance units)</li>
			<li>cs_re,cs_im = real/imaginary parts of wavepacket coefficients</li>
			<li>cv = heat capacity (need units) for SPH particles</li>
			<li>density = density of particle (mass/distance^3 or mass/distance^2 or mass/distance units, depending on dimensionality of particle)</li>
			<li>diameter = diameter of spherical atom (distance units)</li>
			<li>e = energy (need units) for SPH particles</li>
			<li>ellipsoidflag = 1 for ellipsoidal particles, 0 for point particles</li>
			<li>eradius = electron radius (or fixed-core radius)</li>
			<li>etag = integer ID of electron that each wavepacket belongs to</li>
			<li>kernel-radius = ??? (distance units)</li>
			<li>lineflag = 1 for line segment particles, 0 for point or spherical particles</li>
			<li>mass = mass of particle (mass units)</li>
			<li>molecule-ID = integer ID of molecule the atom belongs to</li>
			<li>mux,muy,muz = components of dipole moment of atom (dipole units)</li>
			<li>q = charge on atom (charge units)</li>
			<li>rho = density (need units) for SPH particles</li>
			<li>spin = electron spin (+1/-1), 0 = nuclei, 2 = fixed-core, 3 = pseudo-cores (i.e. ECP)</li>
			<li>template-atom = which atom within a template molecule the atom is</li>
			<li>template-index = which molecule within the molecule template the atom is part of</li>
			<li>theta = internal temperature of a DPD particle</li>
			<li>triangleflag = 1 for triangular particles, 0 for point or sperhical particles</li>
			<li>volume = volume of Peridynamic particle (distance^3 units)</li>
			<li>x,y,z = coordinates of atom (distance units)</li>
			</ul>
			<p>The units for these quantities depend on the unit style; see the
			<a class="reference internal" href="units.html"><span class="doc">units</span></a> command for details.</p>
			<p>For 2d simulations specify z as 0.0, or a value within the <em>zlo zhi</em>
			setting in the data file header.</p>
			<p>The atom-ID is used to identify the atom throughout the simulation and
			in dump files. Normally, it is a unique value from 1 to Natoms for
			each atom. Unique values larger than Natoms can be used, but they
			will cause extra memory to be allocated on each processor, if an atom
			map array is used, but not if an atom map hash is used; see the
			<a class="reference internal" href="atom_modify.html"><span class="doc">atom_modify</span></a> command for details. If an atom map is
			not used (e.g. an atomic system with no bonds), and you don’t care if
			unique atom IDs appear in dump files, then the atom-IDs can all be set
			to 0.</p>
			<p>The molecule ID is a 2nd identifier attached to an atom. Normally, it
			is a number from 1 to N, identifying which molecule the atom belongs
			to. It can be 0 if it is an unbonded atom or if you don’t care to
			keep track of molecule assignments.</p>
			<p>The diameter specifies the size of a finite-size spherical particle.
			It can be set to 0.0, which means that atom is a point particle.</p>
			<p>The ellipsoidflag, lineflag, triangleflag, and bodyflag determine
			whether the particle is a finite-size ellipsoid or line or triangle or
			body of finite size, or whether the particle is a point particle.
			Additional attributes must be defined for each ellipsoid, line,
			triangle, or body in the corresponding <em>Ellipsoids</em>, <em>Lines</em>,
			<em>Triangles</em>, or <em>Bodies</em> section.</p>
			<p>The <em>template-index</em> and <em>template-atom</em> are only defined used by
			<a class="reference internal" href="atom_style.html"><span class="doc">atom_style template</span></a>. In this case the
			<a class="reference internal" href="molecule.html"><span class="doc">molecule</span></a> command is used to define a molecule template
			which contains one or more molecules. If an atom belongs to one of
			those molecules, its <em>template-index</em> and <em>template-atom</em> are both set
			to positive integers; if not the values are both 0. The
			<em>template-index</em> is which molecule (1 to Nmols) the atom belongs to.
			The <em>template-atom</em> is which atom (1 to Natoms) within the molecule
			the atom is.</p>
			<p>Some pair styles and fixes and computes that operate on finite-size
			particles allow for a mixture of finite-size and point particles. See
			the doc pages of individual commands for details.</p>
			<p>For finite-size particles, the density is used in conjunction with the
			particle volume to set the mass of each particle as mass = density *
			volume. In this context, volume can be a 3d quantity (for spheres or
			ellipsoids), a 2d quantity (for triangles), or a 1d quantity (for line
			segments). If the volume is 0.0, meaning a point particle, then the
			density value is used as the mass. One exception is for the body atom
			style, in which case the mass of each particle (body or point
			particle) is specified explicitly. This is because the volume of the
			body is unknown.</p>
			<p>For atom_style hybrid, following the 5 initial values (ID,type,x,y,z),
			specific values for each sub-style must be listed. The order of the
			sub-styles is the same as they were listed in the
			<a class="reference internal" href="atom_style.html"><span class="doc">atom_style</span></a> command. The sub-style specific values
			are those that are not the 5 standard ones (ID,type,x,y,z). For
			example, for the “charge” sub-style, a “q” value would appear. For
			the “full” sub-style, a “molecule-ID” and “q” would appear. These are
			listed in the same order they appear as listed above. Thus if</p>
			<pre class="literal-block">
			atom_style hybrid charge sphere
			</pre>
			<p>were used in the input script, each atom line would have these fields:</p>
			<div class="highlight-default"><div class="highlight"><pre><span></span><span class="n">atom</span><span class="o">-</span><span class="n">ID</span> <span class="n">atom</span><span class="o">-</span><span class="nb">type</span> <span class="n">x</span> <span class="n">y</span> <span class="n">z</span> <span class="n">q</span> <span class="n">diameter</span> <span class="n">density</span>
			</pre></div>
			</div>
			<p>Note that if a non-standard value is defined by multiple sub-styles,
			it must appear mutliple times in the atom line. E.g. the atom line
			for atom_style hybrid dipole full would list “q” twice:</p>
			<div class="highlight-default"><div class="highlight"><pre><span></span><span class="n">atom</span><span class="o">-</span><span class="n">ID</span> <span class="n">atom</span><span class="o">-</span><span class="nb">type</span> <span class="n">x</span> <span class="n">y</span> <span class="n">z</span> <span class="n">q</span> <span class="n">mux</span> <span class="n">muy</span> <span class="n">myz</span> <span class="n">molecule</span><span class="o">-</span><span class="n">ID</span> <span class="n">q</span>
			</pre></div>
			</div>
			<p>Atom lines specify the (x,y,z) coordinates of atoms. These can be
			inside or outside the simulation box. When the data file is read,
			LAMMPS wraps coordinates outside the box back into the box for
			dimensions that are periodic. As discussed above, if an atom is
			outside the box in a non-periodic dimension, it will be lost.</p>
			<p>LAMMPS always stores atom coordinates as values which are inside the
			simulation box. It also stores 3 flags which indicate which image of
			the simulation box (in each dimension) the atom would be in if its
			coordinates were unwrapped across periodic boundaries. An image flag
			of 0 means the atom is still inside the box when unwrapped. A value
			of 2 means add 2 box lengths to get the unwrapped coordinate. A value
			of -1 means subtract 1 box length to get the unwrapped coordinate.
			LAMMPS updates these flags as atoms cross periodic boundaries during
			the simulation. The <a class="reference internal" href="dump.html"><span class="doc">dump</span></a> command can output atom atom
			coordinates in wrapped or unwrapped form, as well as the 3 image
			flags.</p>
			<p>In the data file, atom lines (all lines or none of them) can
			optionally list 3 trailing integer values (nx,ny,nz), which are used
			to initialize the atom’s image flags. If nx,ny,nz values are not
			listed in the data file, LAMMPS initializes them to 0. Note that the
			image flags are immediately updated if an atom’s coordinates need to
			wrapped back into the simulation box.</p>
			<p>It is only important to set image flags correctly in a data file if a
			simulation model relies on unwrapped coordinates for some calculation;
			otherwise they can be left unspecified. Examples of LAMMPS commands
			that use unwrapped coordinates internally are as follows:</p>
			<ul class="simple">
			<li>Atoms in a rigid body (see <a class="reference internal" href="fix_rigid.html"><span class="doc">fix rigid</span></a>, <a class="reference internal" href="fix_rigid.html"><span class="doc">fix rigid/small</span></a>) must have consistent image flags, so that
			when the atoms are unwrapped, they are near each other, i.e. as a
			single body.</li>
			<li>If the <a class="reference internal" href="replicate.html"><span class="doc">replicate</span></a> command is used to generate a larger
			system, image flags must be consistent for bonded atoms when the bond
			crosses a periodic boundary. I.e. the values of the image flags
			should be different by 1 (in the appropriate dimension) for the two
			atoms in such a bond.</li>
			<li>If you plan to <a class="reference internal" href="dump.html"><span class="doc">dump</span></a> image flags and perform post-analysis
			that will unwrap atom coordinates, it may be important that a
			continued run (restarted from a data file) begins with image flags
			that are consistent with the previous run.</li>
			</ul>
			<div class="admonition note">
			<p class="first admonition-title">Note</p>
			<p class="last">If your system is an infinite periodic crystal with bonds then
			it is impossible to have fully consistent image flags. This is because
			some bonds will cross periodic boundaries and connect two atoms with the
			same image flag.</p>
			</div>
			<p>Atom velocities and other atom quantities not defined above are set to
			0.0 when the <em>Atoms</em> section is read. Velocities can be set later by
			a <em>Velocities</em> section in the data file or by a
			<a class="reference internal" href="velocity.html"><span class="doc">velocity</span></a> or <a class="reference internal" href="set.html"><span class="doc">set</span></a> command in the input
			script.</p>
			<hr class="docutils" />
			<p><em>Bodies</em> section:</p>
			<ul>
			<li><p class="first">one or more lines per body</p>
			</li>
			<li><p class="first">first line syntax: atom-ID Ninteger Ndouble</p>
			<div class="highlight-default"><div class="highlight"><pre><span></span><span class="n">Ninteger</span> <span class="o">=</span> <span class="c1"># of integer quantities for this particle</span>
			<span class="n">Ndouble</span> <span class="o">=</span> <span class="c1"># of floating-point quantities for this particle</span>
			</pre></div>
			</div>
			</li>
			<li><p class="first">0 or more integer lines with total of Ninteger values</p>
			</li>
			<li><p class="first">0 or more double lines with total of Ndouble values</p>
			</li>
			<li><p class="first">example:</p>
			<div class="highlight-default"><div class="highlight"><pre><span></span><span class="mi">12</span> <span class="mi">3</span> <span class="mi">6</span>
			<span class="mi">2</span> <span class="mi">3</span> <span class="mi">2</span>
			<span class="mf">1.0</span> <span class="mf">2.0</span> <span class="mf">3.0</span> <span class="mf">1.0</span> <span class="mf">2.0</span> <span class="mf">4.0</span>
			</pre></div>
			</div>
			</li>
			<li><p class="first">example:</p>
			<div class="highlight-default"><div class="highlight"><pre><span></span><span class="mi">12</span> <span class="mi">0</span> <span class="mi">14</span>
			<span class="mf">1.0</span> <span class="mf">2.0</span> <span class="mf">3.0</span> <span class="mf">1.0</span> <span class="mf">2.0</span> <span class="mf">4.0</span> <span class="mf">1.0</span>
			<span class="mf">2.0</span> <span class="mf">3.0</span> <span class="mf">1.0</span> <span class="mf">2.0</span> <span class="mf">4.0</span> <span class="mf">4.0</span> <span class="mf">2.0</span>
			</pre></div>
			</div>
			</li>
			</ul>
			<p>The <em>Bodies</em> section must appear if <a class="reference internal" href="atom_style.html"><span class="doc">atom_style body</span></a>
			is used and any atoms listed in the <em>Atoms</em> section have a bodyflag =
			1. The number of bodies should be specified in the header section via
			the “bodies” keyword.</p>
			<p>Each body can have a variable number of integer and/or floating-point
			values. The number and meaning of the values is defined by the body
			style, as described in the <a class="reference internal" href="body.html"><span class="doc">body</span></a> doc page. The body style
			is given as an argument to the <a class="reference internal" href="atom_style.html"><span class="doc">atom_style body</span></a>
			command.</p>
			<p>The Ninteger and Ndouble values determine how many integer and
			floating-point values are specified for this particle. Ninteger and
			Ndouble can be as large as needed and can be different for every body.
			Integer values are then listed next on subsequent lines. Lines are
			read one at a time until Ninteger values are read. Floating-point
			values follow on subsequent lines, Again lines are read one at a time
			until Ndouble values are read. Note that if there are no values of a
			particular type, no lines appear for that type.</p>
			<p>The <em>Bodies</em> section must appear after the <em>Atoms</em> section.</p>
			<hr class="docutils" />
			<p><em>Bond Coeffs</em> section:</p>
			<ul>
			<li><p class="first">one line per bond type</p>
			</li>
			<li><p class="first">line syntax: ID coeffs</p>
			<div class="highlight-default"><div class="highlight"><pre><span></span><span class="n">ID</span> <span class="o">=</span> <span class="n">bond</span> <span class="nb">type</span> <span class="p">(</span><span class="mi">1</span><span class="o">-</span><span class="n">N</span><span class="p">)</span>
			<span class="n">coeffs</span> <span class="o">=</span> <span class="nb">list</span> <span class="n">of</span> <span class="n">coeffs</span>
			</pre></div>
			</div>
			</li>
			<li><p class="first">example:</p>
			<div class="highlight-default"><div class="highlight"><pre><span></span><span class="mi">4</span> <span class="mi">250</span> <span class="mf">1.49</span>
			</pre></div>
			</div>
			</li>
			</ul>
			<p>The number and meaning of the coefficients are specific to the defined
			bond style. See the <a class="reference internal" href="bond_style.html"><span class="doc">bond_style</span></a> and
			<a class="reference internal" href="bond_coeff.html"><span class="doc">bond_coeff</span></a> commands for details. Coefficients can
			also be set via the <a class="reference internal" href="bond_coeff.html"><span class="doc">bond_coeff</span></a> command in the input
			script.</p>
			<hr class="docutils" />
			<p><em>BondAngle Coeffs</em> section:</p>
			<ul>
			<li><p class="first">one line per angle type</p>
			</li>
			<li><p class="first">line syntax: ID coeffs</p>
			<pre class="literal-block">
			ID = angle type (1-N)
			coeffs = list of coeffs (see class 2 section of <a class="reference internal" href="angle_coeff.html"><span class="doc">angle_coeff</span></a>)
			</pre>
			</li>
			</ul>
			<hr class="docutils" />
			<p><em>BondBond Coeffs</em> section:</p>
			<ul>
			<li><p class="first">one line per angle type</p>
			</li>
			<li><p class="first">line syntax: ID coeffs</p>
			<pre class="literal-block">
			ID = angle type (1-N)
			coeffs = list of coeffs (see class 2 section of <a class="reference internal" href="angle_coeff.html"><span class="doc">angle_coeff</span></a>)
			</pre>
			</li>
			</ul>
			<hr class="docutils" />
			<p><em>BondBond13 Coeffs</em> section:</p>
			<ul>
			<li><p class="first">one line per dihedral type</p>
			</li>
			<li><p class="first">line syntax: ID coeffs</p>
			<pre class="literal-block">
			ID = dihedral type (1-N)
			coeffs = list of coeffs (see class 2 section of <a class="reference internal" href="dihedral_coeff.html"><span class="doc">dihedral_coeff</span></a>)
			</pre>
			</li>
			</ul>
			<hr class="docutils" />
			<p><em>Bonds</em> section:</p>
			<ul>
			<li><p class="first">one line per bond</p>
			</li>
			<li><p class="first">line syntax: ID type atom1 atom2</p>
			<div class="highlight-default"><div class="highlight"><pre><span></span><span class="n">ID</span> <span class="o">=</span> <span class="n">bond</span> <span class="n">number</span> <span class="p">(</span><span class="mi">1</span><span class="o">-</span><span class="n">Nbonds</span><span class="p">)</span>
			<span class="nb">type</span> <span class="o">=</span> <span class="n">bond</span> <span class="nb">type</span> <span class="p">(</span><span class="mi">1</span><span class="o">-</span><span class="n">Nbondtype</span><span class="p">)</span>
			<span class="n">atom1</span><span class="p">,</span><span class="n">atom2</span> <span class="o">=</span> <span class="n">IDs</span> <span class="n">of</span> <span class="mi">1</span><span class="n">st</span><span class="p">,</span><span class="mi">2</span><span class="n">nd</span> <span class="n">atoms</span> <span class="ow">in</span> <span class="n">bond</span>
			</pre></div>
			</div>
			</li>
			<li><p class="first">example:</p>
			<div class="highlight-default"><div class="highlight"><pre><span></span><span class="mi">12</span> <span class="mi">3</span> <span class="mi">17</span> <span class="mi">29</span>
			</pre></div>
			</div>
			</li>
			</ul>
			<p>The <em>Bonds</em> section must appear after the <em>Atoms</em> section. All values
			in this section must be integers (1, not 1.0).</p>
			<hr class="docutils" />
			<p><em>Dihedral Coeffs</em> section:</p>
			<ul>
			<li><p class="first">one line per dihedral type</p>
			</li>
			<li><p class="first">line syntax: ID coeffs</p>
			<div class="highlight-default"><div class="highlight"><pre><span></span><span class="n">ID</span> <span class="o">=</span> <span class="n">dihedral</span> <span class="nb">type</span> <span class="p">(</span><span class="mi">1</span><span class="o">-</span><span class="n">N</span><span class="p">)</span>
			<span class="n">coeffs</span> <span class="o">=</span> <span class="nb">list</span> <span class="n">of</span> <span class="n">coeffs</span>
			</pre></div>
			</div>
			</li>
			<li><p class="first">example:</p>
			<div class="highlight-default"><div class="highlight"><pre><span></span><span class="mi">3</span> <span class="mf">0.6</span> <span class="mi">1</span> <span class="mi">0</span> <span class="mi">1</span>
			</pre></div>
			</div>
			</li>
			</ul>
			<p>The number and meaning of the coefficients are specific to the defined
			dihedral style. See the <a class="reference internal" href="dihedral_style.html"><span class="doc">dihedral_style</span></a> and
			<a class="reference internal" href="dihedral_coeff.html"><span class="doc">dihedral_coeff</span></a> commands for details.
			Coefficients can also be set via the
			<a class="reference internal" href="dihedral_coeff.html"><span class="doc">dihedral_coeff</span></a> command in the input script.</p>
			<hr class="docutils" />
			<p><em>Dihedrals</em> section:</p>
			<ul>
			<li><p class="first">one line per dihedral</p>
			</li>
			<li><p class="first">line syntax: ID type atom1 atom2 atom3 atom4</p>
			<div class="highlight-default"><div class="highlight"><pre><span></span><span class="n">ID</span> <span class="o">=</span> <span class="n">number</span> <span class="n">of</span> <span class="n">dihedral</span> <span class="p">(</span><span class="mi">1</span><span class="o">-</span><span class="n">Ndihedrals</span><span class="p">)</span>
			<span class="nb">type</span> <span class="o">=</span> <span class="n">dihedral</span> <span class="nb">type</span> <span class="p">(</span><span class="mi">1</span><span class="o">-</span><span class="n">Ndihedraltype</span><span class="p">)</span>
			<span class="n">atom1</span><span class="p">,</span><span class="n">atom2</span><span class="p">,</span><span class="n">atom3</span><span class="p">,</span><span class="n">atom4</span> <span class="o">=</span> <span class="n">IDs</span> <span class="n">of</span> <span class="mi">1</span><span class="n">st</span><span class="p">,</span><span class="mi">2</span><span class="n">nd</span><span class="p">,</span><span class="mi">3</span><span class="n">rd</span><span class="p">,</span><span class="mi">4</span><span class="n">th</span> <span class="n">atoms</span> <span class="ow">in</span> <span class="n">dihedral</span>
			</pre></div>
			</div>
			</li>
			<li><p class="first">example:</p>
			<div class="highlight-default"><div class="highlight"><pre><span></span><span class="mi">12</span> <span class="mi">4</span> <span class="mi">17</span> <span class="mi">29</span> <span class="mi">30</span> <span class="mi">21</span>
			</pre></div>
			</div>
			</li>
			</ul>
			<p>The 4 atoms are ordered linearly within the dihedral. The <em>Dihedrals</em>
			section must appear after the <em>Atoms</em> section. All values in this
			section must be integers (1, not 1.0).</p>
			<hr class="docutils" />
			<p><em>Ellipsoids</em> section:</p>
			<ul>
			<li><p class="first">one line per ellipsoid</p>
			</li>
			<li><p class="first">line syntax: atom-ID shapex shapey shapez quatw quati quatj quatk</p>
			<div class="highlight-default"><div class="highlight"><pre><span></span><span class="n">atom</span><span class="o">-</span><span class="n">ID</span> <span class="o">=</span> <span class="n">ID</span> <span class="n">of</span> <span class="n">atom</span> <span class="n">which</span> <span class="ow">is</span> <span class="n">an</span> <span class="n">ellipsoid</span>
			<span class="n">shapex</span><span class="p">,</span><span class="n">shapey</span><span class="p">,</span><span class="n">shapez</span> <span class="o">=</span> <span class="mi">3</span> <span class="n">diameters</span> <span class="n">of</span> <span class="n">ellipsoid</span> <span class="p">(</span><span class="n">distance</span> <span class="n">units</span><span class="p">)</span>
			<span class="n">quatw</span><span class="p">,</span><span class="n">quati</span><span class="p">,</span><span class="n">quatj</span><span class="p">,</span><span class="n">quatk</span> <span class="o">=</span> <span class="n">quaternion</span> <span class="n">components</span> <span class="k">for</span> <span class="n">orientation</span> <span class="n">of</span> <span class="n">atom</span>
			</pre></div>
			</div>
			</li>
			<li><p class="first">example:</p>
			<div class="highlight-default"><div class="highlight"><pre><span></span><span class="mi">12</span> <span class="mi">1</span> <span class="mi">2</span> <span class="mi">1</span> <span class="mi">1</span> <span class="mi">0</span> <span class="mi">0</span> <span class="mi">0</span>
			</pre></div>
			</div>
			</li>
			</ul>
			<p>The <em>Ellipsoids</em> section must appear if <a class="reference internal" href="atom_style.html"><span class="doc">atom_style ellipsoid</span></a> is used and any atoms are listed in the
			<em>Atoms</em> section with an ellipsoidflag = 1. The number of ellipsoids
			should be specified in the header section via the “ellipsoids”
			keyword.</p>
			<p>The 3 shape values specify the 3 diameters or aspect ratios of a
			finite-size ellipsoidal particle, when it is oriented along the 3
			coordinate axes. They must all be non-zero values.</p>
			<p>The values <em>quatw</em>, <em>quati</em>, <em>quatj</em>, and <em>quatk</em> set the orientation
			of the atom as a quaternion (4-vector). Note that the shape
			attributes specify the aspect ratios of an ellipsoidal particle, which
			is oriented by default with its x-axis along the simulation box’s
			x-axis, and similarly for y and z. If this body is rotated (via the
			right-hand rule) by an angle theta around a unit vector (a,b,c), then
			the quaternion that represents its new orientation is given by
			(cos(theta/2), asin(theta/2), bsin(theta/2), c*sin(theta/2)). These
			4 components are quatw, quati, quatj, and quatk as specified above.
			LAMMPS normalizes each atom’s quaternion in case (a,b,c) is not
			specified as a unit vector.</p>
			<p>The <em>Ellipsoids</em> section must appear after the <em>Atoms</em> section.</p>
			<hr class="docutils" />
			<p><em>EndBondTorsion Coeffs</em> section:</p>
			<ul>
			<li><p class="first">one line per dihedral type</p>
			</li>
			<li><p class="first">line syntax: ID coeffs</p>
			<pre class="literal-block">
			ID = dihedral type (1-N)
			coeffs = list of coeffs (see class 2 section of <a class="reference internal" href="dihedral_coeff.html"><span class="doc">dihedral_coeff</span></a>)
			</pre>
			</li>
			</ul>
			<hr class="docutils" />
			<p><em>Improper Coeffs</em> section:</p>
			<ul>
			<li><p class="first">one line per improper type</p>
			</li>
			<li><p class="first">line syntax: ID coeffs</p>
			<div class="highlight-default"><div class="highlight"><pre><span></span><span class="n">ID</span> <span class="o">=</span> <span class="n">improper</span> <span class="nb">type</span> <span class="p">(</span><span class="mi">1</span><span class="o">-</span><span class="n">N</span><span class="p">)</span>
			<span class="n">coeffs</span> <span class="o">=</span> <span class="nb">list</span> <span class="n">of</span> <span class="n">coeffs</span>
			</pre></div>
			</div>
			</li>
			<li><p class="first">example:</p>
			<div class="highlight-default"><div class="highlight"><pre><span></span><span class="mi">2</span> <span class="mi">20</span> <span class="mf">0.0548311</span>
			</pre></div>
			</div>
			</li>
			</ul>
			<p>The number and meaning of the coefficients are specific to the defined
			improper style. See the <a class="reference internal" href="improper_style.html"><span class="doc">improper_style</span></a> and
			<a class="reference internal" href="improper_coeff.html"><span class="doc">improper_coeff</span></a> commands for details.
			Coefficients can also be set via the
			<a class="reference internal" href="improper_coeff.html"><span class="doc">improper_coeff</span></a> command in the input script.</p>
			<hr class="docutils" />
			<p><em>Impropers</em> section:</p>
			<ul>
			<li><p class="first">one line per improper</p>
			</li>
			<li><p class="first">line syntax: ID type atom1 atom2 atom3 atom4</p>
			<div class="highlight-default"><div class="highlight"><pre><span></span><span class="n">ID</span> <span class="o">=</span> <span class="n">number</span> <span class="n">of</span> <span class="n">improper</span> <span class="p">(</span><span class="mi">1</span><span class="o">-</span><span class="n">Nimpropers</span><span class="p">)</span>
			<span class="nb">type</span> <span class="o">=</span> <span class="n">improper</span> <span class="nb">type</span> <span class="p">(</span><span class="mi">1</span><span class="o">-</span><span class="n">Nimpropertype</span><span class="p">)</span>
			<span class="n">atom1</span><span class="p">,</span><span class="n">atom2</span><span class="p">,</span><span class="n">atom3</span><span class="p">,</span><span class="n">atom4</span> <span class="o">=</span> <span class="n">IDs</span> <span class="n">of</span> <span class="mi">1</span><span class="n">st</span><span class="p">,</span><span class="mi">2</span><span class="n">nd</span><span class="p">,</span><span class="mi">3</span><span class="n">rd</span><span class="p">,</span><span class="mi">4</span><span class="n">th</span> <span class="n">atoms</span> <span class="ow">in</span> <span class="n">improper</span>
			</pre></div>
			</div>
			</li>
			<li><p class="first">example:</p>
			<div class="highlight-default"><div class="highlight"><pre><span></span><span class="mi">12</span> <span class="mi">3</span> <span class="mi">17</span> <span class="mi">29</span> <span class="mi">13</span> <span class="mi">100</span>
			</pre></div>
			</div>
			</li>
			</ul>
			<p>The ordering of the 4 atoms determines the definition of the improper
			angle used in the formula for each <a class="reference internal" href="improper_style.html"><span class="doc">improper style</span></a>. See the doc pages for individual styles
			for details.</p>
			<p>The <em>Impropers</em> section must appear after the <em>Atoms</em> section. All
			values in this section must be integers (1, not 1.0).</p>
			<hr class="docutils" />
			<p><em>Lines</em> section:</p>
			<ul>
			<li><p class="first">one line per line segment</p>
			</li>
			<li><p class="first">line syntax: atom-ID x1 y1 x2 y2</p>
			<div class="highlight-default"><div class="highlight"><pre><span></span><span class="n">atom</span><span class="o">-</span><span class="n">ID</span> <span class="o">=</span> <span class="n">ID</span> <span class="n">of</span> <span class="n">atom</span> <span class="n">which</span> <span class="ow">is</span> <span class="n">a</span> <span class="n">line</span> <span class="n">segment</span>
			<span class="n">x1</span><span class="p">,</span><span class="n">y1</span> <span class="o">=</span> <span class="mi">1</span><span class="n">st</span> <span class="n">end</span> <span class="n">point</span>
			<span class="n">x2</span><span class="p">,</span><span class="n">y2</span> <span class="o">=</span> <span class="mi">2</span><span class="n">nd</span> <span class="n">end</span> <span class="n">point</span>
			</pre></div>
			</div>
			</li>
			<li><p class="first">example:</p>
			<div class="highlight-default"><div class="highlight"><pre><span></span><span class="mi">12</span> <span class="mf">1.0</span> <span class="mf">0.0</span> <span class="mf">2.0</span> <span class="mf">0.0</span>
			</pre></div>
			</div>
			</li>
			</ul>
			<p>The <em>Lines</em> section must appear if <a class="reference internal" href="atom_style.html"><span class="doc">atom_style line</span></a>
			is used and any atoms are listed in the <em>Atoms</em> section with a
			lineflag = 1. The number of lines should be specified in the header
			section via the “lines” keyword.</p>
			<p>The 2 end points are the end points of the line segment. The ordering
			of the 2 points should be such that using a right-hand rule to cross
			the line segment with a unit vector in the +z direction, gives an
			“outward” normal vector perpendicular to the line segment.
			I.e. normal = (c2-c1) x (0,0,1). This orientation may be important
			for defining some interactions.</p>
			<p>The <em>Lines</em> section must appear after the <em>Atoms</em> section.</p>
			<hr class="docutils" />
			<p><em>Masses</em> section:</p>
			<ul>
			<li><p class="first">one line per atom type</p>
			</li>
			<li><p class="first">line syntax: ID mass</p>
			<div class="highlight-default"><div class="highlight"><pre><span></span><span class="n">ID</span> <span class="o">=</span> <span class="n">atom</span> <span class="nb">type</span> <span class="p">(</span><span class="mi">1</span><span class="o">-</span><span class="n">N</span><span class="p">)</span>
			<span class="n">mass</span> <span class="o">=</span> <span class="n">mass</span> <span class="n">value</span>
			</pre></div>
			</div>
			</li>
			<li><p class="first">example:</p>
			<div class="highlight-default"><div class="highlight"><pre><span></span><span class="mi">3</span> <span class="mf">1.01</span>
			</pre></div>
			</div>
			</li>
			</ul>
			<p>This defines the mass of each atom type. This can also be set via the
			<a class="reference internal" href="mass.html"><span class="doc">mass</span></a> command in the input script. This section cannot be
			used for atom styles that define a mass for individual atoms -
			e.g. <a class="reference internal" href="atom_style.html"><span class="doc">atom_style sphere</span></a>.</p>
			<hr class="docutils" />
			<p><em>MiddleBondTorsion Coeffs</em> section:</p>
			<ul>
			<li><p class="first">one line per dihedral type</p>
			</li>
			<li><p class="first">line syntax: ID coeffs</p>
			<pre class="literal-block">
			ID = dihedral type (1-N)
			coeffs = list of coeffs (see class 2 section of <a class="reference internal" href="dihedral_coeff.html"><span class="doc">dihedral_coeff</span></a>)
			</pre>
			</li>
			</ul>
			<hr class="docutils" />
			<p><em>Pair Coeffs</em> section:</p>
			<ul>
			<li><p class="first">one line per atom type</p>
			</li>
			<li><p class="first">line syntax: ID coeffs</p>
			<div class="highlight-default"><div class="highlight"><pre><span></span><span class="n">ID</span> <span class="o">=</span> <span class="n">atom</span> <span class="nb">type</span> <span class="p">(</span><span class="mi">1</span><span class="o">-</span><span class="n">N</span><span class="p">)</span>
			<span class="n">coeffs</span> <span class="o">=</span> <span class="nb">list</span> <span class="n">of</span> <span class="n">coeffs</span>
			</pre></div>
			</div>
			</li>
			<li><p class="first">example:</p>
			<div class="highlight-default"><div class="highlight"><pre><span></span><span class="mi">3</span> <span class="mf">0.022</span> <span class="mf">2.35197</span> <span class="mf">0.022</span> <span class="mf">2.35197</span>
			</pre></div>
			</div>
			</li>
			</ul>
			<p>The number and meaning of the coefficients are specific to the defined
			pair style. See the <a class="reference internal" href="pair_style.html"><span class="doc">pair_style</span></a> and
			<a class="reference internal" href="pair_coeff.html"><span class="doc">pair_coeff</span></a> commands for details. Since pair
			coefficients for types I != J are not specified, these will be
			generated automatically by the pair style’s mixing rule. See the
			individual pair_style doc pages and the <a class="reference internal" href="pair_modify.html"><span class="doc">pair_modify mix</span></a> command for details. Pair coefficients can also
			be set via the <a class="reference internal" href="pair_coeff.html"><span class="doc">pair_coeff</span></a> command in the input
			script.</p>
			<hr class="docutils" />
			<p><em>PairIJ Coeffs</em> section:</p>
			<ul>
			<li><p class="first">one line per pair of atom types for all I,J with I <= J</p>
			</li>
			<li><p class="first">line syntax: ID1 ID2 coeffs</p>
			<div class="highlight-default"><div class="highlight"><pre><span></span><span class="n">ID1</span> <span class="o">=</span> <span class="n">atom</span> <span class="nb">type</span> <span class="n">I</span> <span class="o">=</span> <span class="mi">1</span><span class="o">-</span><span class="n">N</span>
			<span class="n">ID2</span> <span class="o">=</span> <span class="n">atom</span> <span class="nb">type</span> <span class="n">J</span> <span class="o">=</span> <span class="n">I</span><span class="o">-</span><span class="n">N</span><span class="p">,</span> <span class="k">with</span> <span class="n">I</span> <span class="o"><=</span> <span class="n">J</span>
			<span class="n">coeffs</span> <span class="o">=</span> <span class="nb">list</span> <span class="n">of</span> <span class="n">coeffs</span>
			</pre></div>
			</div>
			</li>
			<li><p class="first">examples:</p>
			<div class="highlight-default"><div class="highlight"><pre><span></span><span class="mi">3</span> <span class="mi">3</span> <span class="mf">0.022</span> <span class="mf">2.35197</span> <span class="mf">0.022</span> <span class="mf">2.35197</span>
			<span class="mi">3</span> <span class="mi">5</span> <span class="mf">0.022</span> <span class="mf">2.35197</span> <span class="mf">0.022</span> <span class="mf">2.35197</span>
			</pre></div>
			</div>
			</li>
			</ul>
			<p>This section must have N*(N+1)/2 lines where N = # of atom types. The
			number and meaning of the coefficients are specific to the defined
			pair style. See the <a class="reference internal" href="pair_style.html"><span class="doc">pair_style</span></a> and
			<a class="reference internal" href="pair_coeff.html"><span class="doc">pair_coeff</span></a> commands for details. Since pair
			coefficients for types I != J are all specified, these values will
			turn off the default mixing rule defined by the pair style. See the
			individual pair_style doc pages and the <a class="reference internal" href="pair_modify.html"><span class="doc">pair_modify mix</span></a> command for details. Pair coefficients can also
			be set via the <a class="reference internal" href="pair_coeff.html"><span class="doc">pair_coeff</span></a> command in the input
			script.</p>
			<hr class="docutils" />
			<p><em>Triangles</em> section:</p>
			<ul>
			<li><p class="first">one line per triangle</p>
			</li>
			<li><p class="first">line syntax: atom-ID x1 y1 z1 x2 y2 z2 x3 y3 z3</p>
			<div class="highlight-default"><div class="highlight"><pre><span></span><span class="n">atom</span><span class="o">-</span><span class="n">ID</span> <span class="o">=</span> <span class="n">ID</span> <span class="n">of</span> <span class="n">atom</span> <span class="n">which</span> <span class="ow">is</span> <span class="n">a</span> <span class="n">line</span> <span class="n">segment</span>
			<span class="n">x1</span><span class="p">,</span><span class="n">y1</span><span class="p">,</span><span class="n">z1</span> <span class="o">=</span> <span class="mi">1</span><span class="n">st</span> <span class="n">corner</span> <span class="n">point</span>
			<span class="n">x2</span><span class="p">,</span><span class="n">y2</span><span class="p">,</span><span class="n">z2</span> <span class="o">=</span> <span class="mi">2</span><span class="n">nd</span> <span class="n">corner</span> <span class="n">point</span>
			<span class="n">x3</span><span class="p">,</span><span class="n">y3</span><span class="p">,</span><span class="n">z3</span> <span class="o">=</span> <span class="mi">3</span><span class="n">rd</span> <span class="n">corner</span> <span class="n">point</span>
			</pre></div>
			</div>
			</li>
			<li><p class="first">example:</p>
			<div class="highlight-default"><div class="highlight"><pre><span></span><span class="mi">12</span> <span class="mf">0.0</span> <span class="mf">0.0</span> <span class="mf">0.0</span> <span class="mf">2.0</span> <span class="mf">0.0</span> <span class="mf">1.0</span> <span class="mf">0.0</span> <span class="mf">2.0</span> <span class="mf">1.0</span>
			</pre></div>
			</div>
			</li>
			</ul>
			<p>The <em>Triangles</em> section must appear if <a class="reference internal" href="atom_style.html"><span class="doc">atom_style tri</span></a> is used and any atoms are listed in the <em>Atoms</em>
			section with a triangleflag = 1. The number of lines should be
			specified in the header section via the “triangles” keyword.</p>
			<p>The 3 corner points are the corner points of the triangle. The
			ordering of the 3 points should be such that using a right-hand rule
			to go from point1 to point2 to point3 gives an “outward” normal vector
			to the face of the triangle. I.e. normal = (c2-c1) x (c3-c1). This
			orientation may be important for defining some interactions.</p>
			<p>The <em>Triangles</em> section must appear after the <em>Atoms</em> section.</p>
			<hr class="docutils" />
			<p><em>Velocities</em> section:</p>
			<ul class="simple">
			<li>one line per atom</li>
			<li>line syntax: depends on atom style</li>
			</ul>
			<table border="1" class="docutils">
			<colgroup>
			<col width="42%" />
			<col width="58%" />
			</colgroup>
			<tbody valign="top">
			<tr class="row-odd"><td>all styles except those listed</td>
			<td>atom-ID vx vy vz</td>
			</tr>
			<tr class="row-even"><td>electron</td>
			<td>atom-ID vx vy vz ervel</td>
			</tr>
			<tr class="row-odd"><td>ellipsoid</td>
			<td>atom-ID vx vy vz lx ly lz</td>
			</tr>
			<tr class="row-even"><td>sphere</td>
			<td>atom-ID vx vy vz wx wy wz</td>
			</tr>
			<tr class="row-odd"><td>hybrid</td>
			<td>atom-ID vx vy vz sub-style1 sub-style2 ...</td>
			</tr>
			</tbody>
			</table>
			<p>where the keywords have these meanings:</p>
			<p>vx,vy,vz = translational velocity of atom
			lx,ly,lz = angular momentum of aspherical atom
			wx,wy,wz = angular velocity of spherical atom
			ervel = electron radial velocity (0 for fixed-core):ul</p>
			<p>The velocity lines can appear in any order. This section can only be
			used after an <em>Atoms</em> section. This is because the <em>Atoms</em> section
			must have assigned a unique atom ID to each atom so that velocities
			can be assigned to them.</p>
			<p>Vx, vy, vz, and ervel are in <a class="reference internal" href="units.html"><span class="doc">units</span></a> of velocity. Lx, ly,
			lz are in units of angular momentum (distance-velocity-mass). Wx, Wy,
			Wz are in units of angular velocity (radians/time).</p>
			<p>For atom_style hybrid, following the 4 initial values (ID,vx,vy,vz),
			specific values for each sub-style must be listed. The order of the
			sub-styles is the same as they were listed in the
			<a class="reference internal" href="atom_style.html"><span class="doc">atom_style</span></a> command. The sub-style specific values
			are those that are not the 5 standard ones (ID,vx,vy,vz). For
			example, for the “sphere” sub-style, “wx”, “wy”, “wz” values would
			appear. These are listed in the same order they appear as listed
			above. Thus if</p>
			<pre class="literal-block">
			atom_style hybrid electron sphere
			</pre>
			<p>were used in the input script, each velocity line would have these
			fields:</p>
			<div class="highlight-default"><div class="highlight"><pre><span></span><span class="n">atom</span><span class="o">-</span><span class="n">ID</span> <span class="n">vx</span> <span class="n">vy</span> <span class="n">vz</span> <span class="n">ervel</span> <span class="n">wx</span> <span class="n">wy</span> <span class="n">wz</span>
			</pre></div>
			</div>
			<p>Translational velocities can also be set by the
			<a class="reference internal" href="velocity.html"><span class="doc">velocity</span></a> command in the input script.</p>
			</div>
			<hr class="docutils" />
			<div class="section" id="restrictions">
			<h2>Restrictions</h2>
			<p>To read gzipped data files, you must compile LAMMPS with the
			-DLAMMPS_GZIP option - see the <a class="reference internal" href="Section_start.html#start-2"><span class="std std-ref">Making LAMMPS</span></a> section of the documentation.</p>
			</div>
			<div class="section" id="related-commands">
			<h2>Related commands</h2>
			<p><a class="reference internal" href="read_dump.html"><span class="doc">read_dump</span></a>, <a class="reference internal" href="read_restart.html"><span class="doc">read_restart</span></a>,
			<a class="reference internal" href="create_atoms.html"><span class="doc">create_atoms</span></a>, <a class="reference internal" href="write_data.html"><span class="doc">write_data</span></a></p>
			</div>
			<div class="section" id="default">
			<h2>Default</h2>
			<p>The default for all the <em>extra</em> keywords is 0.</p>
			</div>
			</div>


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