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<head><title>compare -- returns boolean value for whether an element is less than another</title>
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<div><h1>compare -- returns boolean value for whether an element is less than another</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>compare(P,a,b)</tt></div>
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<li><div class="single">Inputs:<ul><li><span><tt>P</tt>, <span>an object of class <a href="___Poset.html" title="a class for partially ordered sets (posets)">Poset</a></span></span></li>
<li><span><tt>a</tt>, <span>a <a href="../../Macaulay2Doc/html/___Thing.html">thing</a></span></span></li>
<li><span><tt>b</tt>, <span>a <a href="../../Macaulay2Doc/html/___Thing.html">thing</a></span>, a and b are elements of P</span></li>
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<li><div class="single">Outputs:<ul><li><span><tt>true</tt>, <span>a <a href="../../Macaulay2Doc/html/___Boolean.html">Boolean value</a></span>, if a is less than or equal to b</span></li>
<li><span><tt>false</tt>, <span>a <a href="../../Macaulay2Doc/html/___Boolean.html">Boolean value</a></span>, otherwise</span></li>
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<div class="single"><h2>Description</h2>
<div><div>This function simply looks at two elements in P, and determines what if any relation exists between them.</div>
<table class="examples"><tr><td><pre>i1 : P = poset ({a,b,c}, {(a,b), (a,c)});</pre>
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<tr><td><pre>i2 : compare (P,a,c)
o2 = true</pre>
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<tr><td><pre>i3 : compare (P,c,a)
o3 = false</pre>
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<tr><td><pre>i4 : compare (P,b,c)
o4 = false</pre>
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<div class="single"><h2>Caveat</h2>
<div><p>Note that if two elements are not comparable, compare still returns a value of false.</p>
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<div class="waystouse"><h2>Ways to use <tt>compare</tt> :</h2>
<ul><li>compare(Poset,Thing,Thing)</li>
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