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<head><title>isEdge -- determines if an edge is in a (hyper)graph</title>
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<div><h1>isEdge -- determines if an edge is in a (hyper)graph</h1>
<div class="single"><h2>Synopsis</h2>
<ul><li><div class="list"><dl class="element"><dt class="heading">Usage: </dt><dd class="value"><div><tt>b = isEdge(H,E)</tt><br/><tt>b = isEdge(H,M)</tt></div>
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<li><div class="single">Inputs:<ul><li><span><tt>H</tt>, <span>a <a href="___Hyper__Graph.html">hypergraph</a></span></span></li>
<li><span><tt>E</tt>, <span>a <a href="../../Macaulay2Doc/html/___List.html">list</a></span>, of vertices</span></li>
<li><span><tt>M</tt>, <span>a <a href="../../Macaulay2Doc/html/___Ring__Element.html">ring element</a></span>, a monomial representing an edge</span></li>
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<li><div class="single">Outputs:<ul><li><span><tt>b</tt>, <span>a <a href="../../Macaulay2Doc/html/___Boolean.html">Boolean value</a></span>, <tt>true</tt> iff <tt>E</tt> (or <tt>support M</tt>) is an edge of <tt>H</tt></span></li>
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<div class="single"><h2>Description</h2>
<div><div>This function checks if a given edge, represented either as a list or monomial, belongs to a given (hyper)graph.</div>
<table class="examples"><tr><td><pre>i1 : S = QQ[z_1..z_8];</pre>
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<tr><td><pre>i2 : h = hyperGraph {z_2*z_3*z_4,z_6*z_8,z_7*z_5,z_1*z_6*z_7,z_2*z_4*z_8};</pre>
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<tr><td><pre>i3 : edges h
o3 = {{z , z , z }, {z , z }, {z , z , z }, {z , z , z }, {z , z }}
2 3 4 5 7 1 6 7 2 4 8 6 8
o3 : List</pre>
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<tr><td><pre>i4 : isEdge (h,{z_2,z_4,z_8})
o4 = true</pre>
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<tr><td><pre>i5 : isEdge (h,z_2*z_3*z_4)
o5 = true</pre>
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<tr><td><pre>i6 : isEdge (h,{z_1,z_2})
o6 = false</pre>
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<div class="single"><h2>See also</h2>
<ul><li><span><a href="_get__Edge__Index.html" title="finds the index of an edge in a HyperGraph">getEdgeIndex</a> -- finds the index of an edge in a HyperGraph</span></li>
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<div class="waystouse"><h2>Ways to use <tt>isEdge</tt> :</h2>
<ul><li>isEdge(HyperGraph,List)</li>
<li>isEdge(HyperGraph,RingElement)</li>
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