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<li class="toctree-l1"><a class="reference internal" href="Section_intro.html">1. Introduction</a></li>
<li class="toctree-l1"><a class="reference internal" href="Section_start.html">2. Getting Started</a></li>
<li class="toctree-l1"><a class="reference internal" href="Section_commands.html">3. Commands</a></li>
<li class="toctree-l1"><a class="reference internal" href="Section_packages.html">4. Packages</a></li>
<li class="toctree-l1"><a class="reference internal" href="Section_accelerate.html">5. Accelerating LAMMPS performance</a></li>
<li class="toctree-l1"><a class="reference internal" href="Section_howto.html">6. How-to discussions</a></li>
<li class="toctree-l1"><a class="reference internal" href="Section_example.html">7. Example problems</a></li>
<li class="toctree-l1"><a class="reference internal" href="Section_perf.html">8. Performance &amp; scalability</a></li>
<li class="toctree-l1"><a class="reference internal" href="Section_tools.html">9. Additional tools</a></li>
<li class="toctree-l1"><a class="reference internal" href="Section_modify.html">10. Modifying &amp; extending LAMMPS</a></li>
<li class="toctree-l1"><a class="reference internal" href="Section_python.html">11. Python interface to LAMMPS</a></li>
<li class="toctree-l1"><a class="reference internal" href="Section_errors.html">12. Errors</a></li>
<li class="toctree-l1"><a class="reference internal" href="Section_history.html">13. Future and history</a></li>
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<p class="caption"><span class="caption-text">Index</span></p>
<ul class="current">
<li class="toctree-l1"><a class="reference internal" href="tutorials.html">Tutorials</a></li>
<li class="toctree-l1"><a class="reference internal" href="commands.html">Commands</a></li>
<li class="toctree-l1"><a class="reference internal" href="fixes.html">Fixes</a></li>
<li class="toctree-l1 current"><a class="reference internal" href="computes.html">Computes</a><ul class="current">
<li class="toctree-l2"><a class="reference internal" href="compute_ackland_atom.html">compute ackland/atom command</a></li>
<li class="toctree-l2"><a class="reference internal" href="compute_angle.html">compute angle command</a></li>
<li class="toctree-l2"><a class="reference internal" href="compute_angle_local.html">compute angle/local command</a></li>
<li class="toctree-l2"><a class="reference internal" href="compute_angmom_chunk.html">compute angmom/chunk command</a></li>
<li class="toctree-l2"><a class="reference internal" href="compute_basal_atom.html">compute basal/atom command</a></li>
<li class="toctree-l2"><a class="reference internal" href="compute_body_local.html">compute body/local command</a></li>
<li class="toctree-l2"><a class="reference internal" href="compute_bond.html">compute bond command</a></li>
<li class="toctree-l2"><a class="reference internal" href="compute_bond_local.html">compute bond/local command</a></li>
<li class="toctree-l2"><a class="reference internal" href="compute_centro_atom.html">compute centro/atom command</a></li>
<li class="toctree-l2"><a class="reference internal" href="compute_chunk_atom.html">compute chunk/atom command</a></li>
<li class="toctree-l2"><a class="reference internal" href="compute_cluster_atom.html">compute cluster/atom command</a></li>
<li class="toctree-l2"><a class="reference internal" href="compute_cna_atom.html">compute cna/atom command</a></li>
<li class="toctree-l2"><a class="reference internal" href="compute_com.html">compute com command</a></li>
<li class="toctree-l2"><a class="reference internal" href="compute_com_chunk.html">compute com/chunk command</a></li>
<li class="toctree-l2"><a class="reference internal" href="compute_contact_atom.html">compute contact/atom command</a></li>
<li class="toctree-l2"><a class="reference internal" href="compute_coord_atom.html">compute coord/atom command</a></li>
<li class="toctree-l2"><a class="reference internal" href="compute_damage_atom.html">compute damage/atom command</a></li>
<li class="toctree-l2"><a class="reference internal" href="compute_dihedral.html">compute dihedral command</a></li>
<li class="toctree-l2"><a class="reference internal" href="compute_dihedral_local.html">compute dihedral/local command</a></li>
<li class="toctree-l2"><a class="reference internal" href="compute_dilatation_atom.html">compute dilatation/atom command</a></li>
<li class="toctree-l2"><a class="reference internal" href="compute_dipole_chunk.html">compute dipole/chunk command</a></li>
<li class="toctree-l2"><a class="reference internal" href="compute_displace_atom.html">compute displace/atom command</a></li>
<li class="toctree-l2"><a class="reference internal" href="compute_dpd.html">compute dpd command</a></li>
<li class="toctree-l2"><a class="reference internal" href="compute_dpd_atom.html">compute dpd/atom command</a></li>
<li class="toctree-l2"><a class="reference internal" href="compute_erotate_asphere.html">compute erotate/asphere command</a></li>
<li class="toctree-l2"><a class="reference internal" href="compute_erotate_rigid.html">compute erotate/rigid command</a></li>
<li class="toctree-l2"><a class="reference internal" href="compute_erotate_sphere.html">compute erotate/sphere command</a></li>
<li class="toctree-l2"><a class="reference internal" href="compute_erotate_sphere_atom.html">compute erotate/sphere/atom command</a></li>
<li class="toctree-l2"><a class="reference internal" href="compute_event_displace.html">compute event/displace command</a></li>
<li class="toctree-l2"><a class="reference internal" href="compute_fep.html">compute fep command</a></li>
<li class="toctree-l2"><a class="reference internal" href="compute_group_group.html">compute group/group command</a></li>
<li class="toctree-l2"><a class="reference internal" href="compute_gyration.html">compute gyration command</a></li>
<li class="toctree-l2"><a class="reference internal" href="compute_gyration_chunk.html">compute gyration/chunk command</a></li>
<li class="toctree-l2"><a class="reference internal" href="compute_heat_flux.html">compute heat/flux command</a></li>
<li class="toctree-l2"><a class="reference internal" href="compute_hexorder_atom.html">compute hexorder/atom command</a></li>
<li class="toctree-l2"><a class="reference internal" href="compute_improper.html">compute improper command</a></li>
<li class="toctree-l2"><a class="reference internal" href="compute_improper_local.html">compute improper/local command</a></li>
<li class="toctree-l2"><a class="reference internal" href="compute_inertia_chunk.html">compute inertia/chunk command</a></li>
<li class="toctree-l2"><a class="reference internal" href="compute_ke.html">compute ke command</a></li>
<li class="toctree-l2"><a class="reference internal" href="compute_ke_atom.html">compute ke/atom command</a></li>
<li class="toctree-l2"><a class="reference internal" href="compute_ke_atom_eff.html">compute ke/atom/eff command</a></li>
<li class="toctree-l2"><a class="reference internal" href="compute_ke_eff.html">compute ke/eff command</a></li>
<li class="toctree-l2"><a class="reference internal" href="compute_ke_rigid.html">compute ke/rigid command</a></li>
<li class="toctree-l2"><a class="reference internal" href="compute_meso_e_atom.html">compute meso/e/atom command</a></li>
<li class="toctree-l2"><a class="reference internal" href="compute_meso_rho_atom.html">compute meso/rho/atom command</a></li>
<li class="toctree-l2"><a class="reference internal" href="compute_meso_t_atom.html">compute meso/t/atom command</a></li>
<li class="toctree-l2"><a class="reference internal" href="compute_msd.html">compute msd command</a></li>
<li class="toctree-l2"><a class="reference internal" href="compute_msd_chunk.html">compute msd/chunk command</a></li>
<li class="toctree-l2"><a class="reference internal" href="compute_msd_nongauss.html">compute msd/nongauss command</a></li>
<li class="toctree-l2"><a class="reference internal" href="compute_omega_chunk.html">compute omega/chunk command</a></li>
<li class="toctree-l2"><a class="reference internal" href="compute_orientorder_atom.html">compute orientorder/atom command</a></li>
<li class="toctree-l2"><a class="reference internal" href="compute_pair.html">compute pair command</a></li>
<li class="toctree-l2"><a class="reference internal" href="compute_pair_local.html">compute pair/local command</a></li>
<li class="toctree-l2"><a class="reference internal" href="compute_pe.html">compute pe command</a></li>
<li class="toctree-l2"><a class="reference internal" href="compute_pe_atom.html">compute pe/atom command</a></li>
<li class="toctree-l2"><a class="reference internal" href="compute_plasticity_atom.html">compute plasticity/atom command</a></li>
<li class="toctree-l2"><a class="reference internal" href="compute_pressure.html">compute pressure command</a></li>
<li class="toctree-l2"><a class="reference internal" href="compute_property_atom.html">compute property/atom command</a></li>
<li class="toctree-l2"><a class="reference internal" href="compute_property_chunk.html">compute property/chunk command</a></li>
<li class="toctree-l2"><a class="reference internal" href="compute_property_local.html">compute property/local command</a></li>
<li class="toctree-l2 current"><a class="current reference internal" href="#">compute rdf 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>
<li class="toctree-l3"><a class="reference internal" href="#restrictions">Restrictions</a></li>
<li class="toctree-l3"><a class="reference internal" href="#related-commands">Related commands</a></li>
</ul>
</li>
<li class="toctree-l2"><a class="reference internal" href="compute_reduce.html">compute reduce command</a></li>
<li class="toctree-l2"><a class="reference internal" href="compute_reduce.html#compute-reduce-region-command">compute reduce/region command</a></li>
<li class="toctree-l2"><a class="reference internal" href="compute_rigid_local.html">compute rigid/local command</a></li>
<li class="toctree-l2"><a class="reference internal" href="compute_saed.html">compute saed command</a></li>
<li class="toctree-l2"><a class="reference internal" href="compute_slice.html">compute slice command</a></li>
<li class="toctree-l2"><a class="reference internal" href="compute_smd_contact_radius.html">compute smd/contact/radius command</a></li>
<li class="toctree-l2"><a class="reference internal" href="compute_smd_damage.html">compute smd/damage command</a></li>
<li class="toctree-l2"><a class="reference internal" href="compute_smd_hourglass_error.html">compute smd/hourglass/error command</a></li>
<li class="toctree-l2"><a class="reference internal" href="compute_smd_internal_energy.html">compute smd/internal/energy command</a></li>
<li class="toctree-l2"><a class="reference internal" href="compute_smd_plastic_strain.html">compute smd/plastic/strain command</a></li>
<li class="toctree-l2"><a class="reference internal" href="compute_smd_plastic_strain_rate.html">compute smd/plastic/strain/rate command</a></li>
<li class="toctree-l2"><a class="reference internal" href="compute_smd_rho.html">compute smd/rho command</a></li>
<li class="toctree-l2"><a class="reference internal" href="compute_smd_tlsph_defgrad.html">compute smd/tlsph/defgrad command</a></li>
<li class="toctree-l2"><a class="reference internal" href="compute_smd_tlsph_dt.html">compute smd/tlsph/dt command</a></li>
<li class="toctree-l2"><a class="reference internal" href="compute_smd_tlsph_num_neighs.html">compute smd/tlsph/num/neighs command</a></li>
<li class="toctree-l2"><a class="reference internal" href="compute_smd_tlsph_shape.html">compute smd/tlsph/shape command</a></li>
<li class="toctree-l2"><a class="reference internal" href="compute_smd_tlsph_strain.html">compute smd/tlsph/strain command</a></li>
<li class="toctree-l2"><a class="reference internal" href="compute_smd_tlsph_strain_rate.html">compute smd/tlsph/strain/rate command</a></li>
<li class="toctree-l2"><a class="reference internal" href="compute_smd_tlsph_stress.html">compute smd/tlsph/stress command</a></li>
<li class="toctree-l2"><a class="reference internal" href="compute_smd_triangle_mesh_vertices.html">compute smd/triangle/mesh/vertices</a></li>
<li class="toctree-l2"><a class="reference internal" href="compute_smd_ulsph_num_neighs.html">compute smd/ulsph/num/neighs command</a></li>
<li class="toctree-l2"><a class="reference internal" href="compute_smd_ulsph_strain.html">compute smd/ulsph/strain command</a></li>
<li class="toctree-l2"><a class="reference internal" href="compute_smd_ulsph_strain_rate.html">compute smd/ulsph/strain/rate command</a></li>
<li class="toctree-l2"><a class="reference internal" href="compute_smd_ulsph_stress.html">compute smd/ulsph/stress command</a></li>
<li class="toctree-l2"><a class="reference internal" href="compute_smd_vol.html">compute smd/vol command</a></li>
<li class="toctree-l2"><a class="reference internal" href="compute_sna_atom.html">compute sna/atom command</a></li>
<li class="toctree-l2"><a class="reference internal" href="compute_sna_atom.html#compute-snad-atom-command">compute snad/atom command</a></li>
<li class="toctree-l2"><a class="reference internal" href="compute_sna_atom.html#compute-snav-atom-command">compute snav/atom command</a></li>
<li class="toctree-l2"><a class="reference internal" href="compute_stress_atom.html">compute stress/atom command</a></li>
<li class="toctree-l2"><a class="reference internal" href="compute_tally.html">compute force/tally command</a></li>
<li class="toctree-l2"><a class="reference internal" href="compute_tally.html#compute-heat-flux-tally-command">compute heat/flux/tally command</a></li>
<li class="toctree-l2"><a class="reference internal" href="compute_tally.html#compute-pe-tally-command">compute pe/tally command</a></li>
<li class="toctree-l2"><a class="reference internal" href="compute_tally.html#compute-pe-mol-tally-command">compute pe/mol/tally command</a></li>
<li class="toctree-l2"><a class="reference internal" href="compute_tally.html#compute-stress-tally-command">compute stress/tally command</a></li>
<li class="toctree-l2"><a class="reference internal" href="compute_temp.html">compute temp command</a></li>
<li class="toctree-l2"><a class="reference internal" href="compute_temp.html#compute-temp-kk-command">compute temp/kk command</a></li>
<li class="toctree-l2"><a class="reference internal" href="compute_temp_asphere.html">compute temp/asphere command</a></li>
<li class="toctree-l2"><a class="reference internal" href="compute_temp_body.html">compute temp/body command</a></li>
<li class="toctree-l2"><a class="reference internal" href="compute_temp_chunk.html">compute temp/chunk command</a></li>
<li class="toctree-l2"><a class="reference internal" href="compute_temp_com.html">compute temp/com command</a></li>
<li class="toctree-l2"><a class="reference internal" href="compute_temp_cs.html">compute temp/cs command</a></li>
<li class="toctree-l2"><a class="reference internal" href="compute_temp_deform.html">compute temp/deform command</a></li>
<li class="toctree-l2"><a class="reference internal" href="compute_temp_deform_eff.html">compute temp/deform/eff command</a></li>
<li class="toctree-l2"><a class="reference internal" href="compute_temp_drude.html">compute temp/drude command</a></li>
<li class="toctree-l2"><a class="reference internal" href="compute_temp_eff.html">compute temp/eff command</a></li>
<li class="toctree-l2"><a class="reference internal" href="compute_temp_partial.html">compute temp/partial command</a></li>
<li class="toctree-l2"><a class="reference internal" href="compute_temp_profile.html">compute temp/profile command</a></li>
<li class="toctree-l2"><a class="reference internal" href="compute_temp_ramp.html">compute temp/ramp command</a></li>
<li class="toctree-l2"><a class="reference internal" href="compute_temp_region.html">compute temp/region command</a></li>
<li class="toctree-l2"><a class="reference internal" href="compute_temp_region_eff.html">compute temp/region/eff command</a></li>
<li class="toctree-l2"><a class="reference internal" href="compute_temp_rotate.html">compute temp/rotate command</a></li>
<li class="toctree-l2"><a class="reference internal" href="compute_temp_sphere.html">compute temp/sphere command</a></li>
<li class="toctree-l2"><a class="reference internal" href="compute_ti.html">compute ti command</a></li>
<li class="toctree-l2"><a class="reference internal" href="compute_torque_chunk.html">compute torque/chunk command</a></li>
<li class="toctree-l2"><a class="reference internal" href="compute_vacf.html">compute vacf command</a></li>
<li class="toctree-l2"><a class="reference internal" href="compute_vcm_chunk.html">compute vcm/chunk command</a></li>
<li class="toctree-l2"><a class="reference internal" href="compute_voronoi_atom.html">compute voronoi/atom command</a></li>
<li class="toctree-l2"><a class="reference internal" href="compute_xrd.html">compute xrd command</a></li>
</ul>
</li>
<li class="toctree-l1"><a class="reference internal" href="pairs.html">Pair Styles</a></li>
<li class="toctree-l1"><a class="reference internal" href="bonds.html">Bond Styles</a></li>
<li class="toctree-l1"><a class="reference internal" href="angles.html">Angle Styles</a></li>
<li class="toctree-l1"><a class="reference internal" href="dihedrals.html">Dihedral Styles</a></li>
<li class="toctree-l1"><a class="reference internal" href="impropers.html">Improper Styles</a></li>
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<div class="section" id="compute-rdf-command">
<span id="index-0"></span><h1>compute rdf command</h1>
<div class="section" id="syntax">
<h2>Syntax</h2>
<div class="highlight-default"><div class="highlight"><pre><span></span><span class="n">compute</span> <span class="n">ID</span> <span class="n">group</span><span class="o">-</span><span class="n">ID</span> <span class="n">rdf</span> <span class="n">Nbin</span> <span class="n">itype1</span> <span class="n">jtype1</span> <span class="n">itype2</span> <span class="n">jtype2</span> <span class="o">...</span>
</pre></div>
</div>
<ul class="simple">
<li>ID, group-ID are documented in <a class="reference internal" href="compute.html"><span class="doc">compute</span></a> command</li>
<li>rdf = style name of this compute command</li>
<li>Nbin = number of RDF bins</li>
<li>itypeN = central atom type for Nth RDF histogram (see asterisk form below)</li>
<li>jtypeN = distribution atom type for Nth RDF histogram (see asterisk form below)</li>
</ul>
</div>
<div class="section" id="examples">
<h2>Examples</h2>
<pre class="literal-block">
compute 1 all rdf 100
compute 1 all rdf 100 1 1
compute 1 all rdf 100 * 3
compute 1 fluid rdf 500 1 1 1 2 2 1 2 2
compute 1 fluid rdf 500 1*3 2 5 *10
</pre>
</div>
<div class="section" id="description">
<h2>Description</h2>
<p>Define a computation that calculates the radial distribution function
(RDF), also called g(r), and the coordination number for a group of
particles. Both are calculated in histogram form by binning pairwise
distances into <em>Nbin</em> bins from 0.0 to the maximum force cutoff
defined by the <a class="reference internal" href="pair_style.html"><span class="doc">pair_style</span></a> command. The bins are of
uniform size in radial distance. Thus a single bin encompasses a thin
shell of distances in 3d and a thin ring of distances in 2d.</p>
<div class="admonition note">
<p class="first admonition-title">Note</p>
<p class="last">If you have a bonded system, then the settings of
<a class="reference internal" href="special_bonds.html"><span class="doc">special_bonds</span></a> command can remove pairwise
interactions between atoms in the same bond, angle, or dihedral. This
is the default setting for the <a class="reference internal" href="special_bonds.html"><span class="doc">special_bonds</span></a>
command, and means those pairwise interactions do not appear in the
neighbor list. Because this fix uses the neighbor list, it also means
those pairs will not be included in the RDF. This does not apply when
using long-range coulomb (<em>coul/long</em>, <em>coul/msm</em>, <em>coul/wolf</em> or
similar. One way to get around this would be to set special_bond
scaling factors to very tiny numbers that are not exactly zero
(e.g. 1.0e-50). Another workaround is to write a dump file, and use
the <a class="reference internal" href="rerun.html"><span class="doc">rerun</span></a> command to compute the RDF for snapshots in the
dump file. The rerun script can use a
<a class="reference internal" href="special_bonds.html"><span class="doc">special_bonds</span></a> command that includes all pairs in
the neighbor list.</p>
</div>
<p>The <em>itypeN</em> and <em>jtypeN</em> arguments are optional. These arguments
must come in pairs. If no pairs are listed, then a single histogram
is computed for g(r) between all atom types. If one or more pairs are
listed, then a separate histogram is generated for each
<em>itype</em>,<em>jtype</em> pair.</p>
<p>The <em>itypeN</em> and <em>jtypeN</em> settings can be specified in one of two
ways. An explicit numeric value can be used, as in the 4th example
above. Or a wild-card asterisk can be used to specify a range of atom
types. This takes the form &#8220;*&#8221; or &#8220;*n&#8221; or &#8220;n*&#8221; or &#8220;m*n&#8221;. If N = the
number of atom types, then an asterisk with no numeric values means
all types from 1 to N. A leading asterisk means all types from 1 to n
(inclusive). A trailing asterisk means all types from n to N
(inclusive). A middle asterisk means all types from m to n
(inclusive).</p>
<p>If both <em>itypeN</em> and <em>jtypeN</em> are single values, as in the 4th example
above, this means that a g(r) is computed where atoms of type <em>itypeN</em>
are the central atom, and atoms of type <em>jtypeN</em> are the distribution
atom. If either <em>itypeN</em> and <em>jtypeN</em> represent a range of values via
the wild-card asterisk, as in the 5th example above, this means that a
g(r) is computed where atoms of any of the range of types represented
by <em>itypeN</em> are the central atom, and atoms of any of the range of
types represented by <em>jtypeN</em> are the distribution atom.</p>
<p>Pairwise distances are generated by looping over a pairwise neighbor
list, just as they would be in a <a class="reference internal" href="pair_style.html"><span class="doc">pair_style</span></a>
computation. The distance between two atoms I and J is included in a
specific histogram if the following criteria are met:</p>
<ul class="simple">
<li>atoms I,J are both in the specified compute group</li>
<li>the distance between atoms I,J is less than the maximum force cutoff</li>
<li>the type of the I atom matches itypeN (one or a range of types)</li>
<li>the type of the J atom matches jtypeN (one or a range of types)</li>
</ul>
<p>It is OK if a particular pairwise distance is included in more than
one individual histogram, due to the way the <em>itypeN</em> and <em>jtypeN</em>
arguments are specified.</p>
<p>The g(r) value for a bin is calculated from the histogram count by
scaling it by the idealized number of how many counts there would be
if atoms of type <em>jtypeN</em> were uniformly distributed. Thus it
involves the count of <em>itypeN</em> atoms, the count of <em>jtypeN</em> atoms, the
volume of the entire simulation box, and the volume of the bin&#8217;s thin
shell in 3d (or the area of the bin&#8217;s thin ring in 2d).</p>
<p>A coordination number coord(r) is also calculated, which is the number
of atoms of type <em>jtypeN</em> within the current bin or closer, averaged
over atoms of type <em>itypeN</em>. This is calculated as the area- or
volume-weighted sum of g(r) values over all bins up to and including
the current bin, multiplied by the global average volume density of
atoms of type jtypeN.</p>
<p>The simplest way to output the results of the compute rdf calculation
to a file is to use the <a class="reference internal" href="fix_ave_time.html"><span class="doc">fix ave/time</span></a> command, for
example:</p>
<pre class="literal-block">
compute myRDF all rdf 50
fix 1 all ave/time 100 1 100 c_myRDF[*] file tmp.rdf mode vector
</pre>
<p><strong>Output info:</strong></p>
<p>This compute calculates a global array with the number of rows =
<em>Nbins</em>, and the number of columns = 1 + 2*Npairs, where Npairs is the
number of I,J pairings specified. The first column has the bin
coordinate (center of the bin), Each successive set of 2 columns has
the g(r) and coord(r) values for a specific set of <em>itypeN</em> versus
<em>jtypeN</em> interactions, as described above. These values can be used
by any command that uses a global values from a compute as input. See
<a class="reference internal" href="Section_howto.html#howto-15"><span class="std std-ref">Section 6.15</span></a> for an overview of
LAMMPS output options.</p>
<p>The array values calculated by this compute are all &#8220;intensive&#8221;.</p>
<p>The first column of array values will be in distance
<a class="reference internal" href="units.html"><span class="doc">units</span></a>. The g(r) columns of array values are normalized
numbers &gt;= 0.0. The coordination number columns of array values are
also numbers &gt;= 0.0.</p>
</div>
<div class="section" id="restrictions">
<h2>Restrictions</h2>
<p>The RDF is not computed for distances longer than the force cutoff,
since processors (in parallel) don&#8217;t know about atom coordinates for
atoms further away than that distance. If you want an RDF for larger
distances, you can use the <a class="reference internal" href="rerun.html"><span class="doc">rerun</span></a> command to post-process
a dump file and set the cutoff for the potential to be longer in the
rerun script. Note that in the rerun context, the force cutoff is
arbitrary, since you aren&#8217;t running dynamics and thus are not changing
your model. The definition of g(r) used by LAMMPS is only appropriate
for characterizing atoms that are uniformly distributed throughout the
simulation cell. In such cases, the coordination number is still
correct and meaningful. As an example, if a large simulation cell
contains only one atom of type <em>itypeN</em> and one of <em>jtypeN</em>, then g(r)
will register an arbitrarily large spike at whatever distance they
happen to be at, and zero everywhere else. Coord(r) will show a step
change from zero to one at the location of the spike in g(r).</p>
</div>
<div class="section" id="related-commands">
<h2>Related commands</h2>
<p><a class="reference internal" href="fix_ave_time.html"><span class="doc">fix ave/time</span></a></p>
<p><strong>Default:</strong> none</p>
</div>
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