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<head><title>isPointed -- checks if a Cone or Fan is pointed</title>
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<div><h1>isPointed -- checks if a Cone or Fan is pointed</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 = isPointed C </tt><br/><tt>b = isPointed F</tt></div>
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<li><div class="single">Inputs:<ul><li><span><tt>C</tt>, <span>a <a href="___Cone.html">convex rational cone</a></span></span></li>
<li><span><tt>F</tt>, <span>an object of class <a href="___Fan.html" title="the class of all fans">Fan</a></span></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>, <a href="../../Macaulay2Doc/html/_true.html" title="">true</a> if the <a href="___Cone.html" title="the class of all rational convex polyhedral cones">Cone</a> or the <a href="___Fan.html" title="the class of all fans">Fan</a> is pointed, false otherwise</span></li>
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<div class="single"><h2>Description</h2>
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Tests if a Cone is pointed, i.e. the lineality space is 0. A Fan is pointed if one of its
Cones is pointed. This is equivalent to all Cones being pointed.<table class="examples"><tr><td><pre>i1 : C = intersection(matrix{{1,1,-1},{-1,-1,-1}})
o1 = {ambient dimension => 3 }
dimension of lineality space => 1
dimension of the cone => 3
number of facets => 2
number of rays => 2
o1 : Cone</pre>
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<tr><td><pre>i2 : isPointed C
o2 = false</pre>
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<tr><td><pre>i3 : C = intersection{C,(matrix{{1,-1,-1}},0)}
o3 = {ambient dimension => 3 }
dimension of lineality space => 0
dimension of the cone => 3
number of facets => 3
number of rays => 3
o3 : Cone</pre>
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<tr><td><pre>i4 : isPointed C
o4 = true</pre>
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<div class="waystouse"><h2>Ways to use <tt>isPointed</tt> :</h2>
<ul><li>isPointed(Cone)</li>
<li>isPointed(Fan)</li>
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