<spanid="index-0"></span><h1>compute contact/atom command<aclass="headerlink"href="#compute-contact-atom-command"title="Permalink to this headline">¶</a></h1>
<divclass="section"id="syntax">
<h2>Syntax<aclass="headerlink"href="#syntax"title="Permalink to this headline">¶</a></h2>
<divclass="highlight-python"><divclass="highlight"><pre>compute ID group-ID contact/atom
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<ulclass="simple">
<li>ID, group-ID are documented in <aclass="reference internal"href="compute.html"><em>compute</em></a> command</li>
<li>contact/atom = style name of this compute command</li>
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<divclass="section"id="examples">
<h2>Examples<aclass="headerlink"href="#examples"title="Permalink to this headline">¶</a></h2>
<divclass="highlight-python"><divclass="highlight"><pre>compute 1 all contact/atom
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<divclass="section"id="description">
<h2>Description<aclass="headerlink"href="#description"title="Permalink to this headline">¶</a></h2>
<p>Define a computation that calculates the number of contacts
for each atom in a group.</p>
<p>The contact number is defined for finite-size spherical particles as
the number of neighbor atoms which overlap the central particle,
meaning that their distance of separation is less than or equal to the
sum of the radii of the two particles.</p>
<p>The value of the contact number will be 0.0 for atoms not in the
specified compute group.</p>
<p><strong>Output info:</strong></p>
<p>This compute calculates a per-atom vector, whose values can be
accessed by any command that uses per-atom values from a compute as
input. See <aclass="reference internal"href="Section_howto.html#howto-15"><span>Section_howto 15</span></a> for an
overview of LAMMPS output options.</p>
<p>The per-atom vector values will be a number >= 0.0, as explained
above.</p>
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<divclass="section"id="restrictions">
<h2>Restrictions<aclass="headerlink"href="#restrictions"title="Permalink to this headline">¶</a></h2>
<p>This compute requires that atoms store a radius as defined by the
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