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<head><title>possibleDenominators -- Possible denominators of deformations.</title>
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<div><h1>possibleDenominators -- Possible denominators of deformations.</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>possibleDenominators(I)</tt><br/><tt>possibleDenominators(I,v)</tt></div>
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<li><div class="single">Inputs:<ul><li><span><tt>I</tt>, <span>an <a href="../../Macaulay2Doc/html/___Ideal.html">ideal</a></span>, monomial, reduced.</span></li>
<li><span><tt>v</tt>, <span>a <a href="../../Macaulay2Doc/html/___List.html">list</a></span>, of variables of <a href="../../Macaulay2Doc/html/_ring.html" title="get the associated ring of an object">ring</a> I.</span></li>
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<li><div class="single">Outputs:<ul><li><span><tt>L</tt>, <span>a <a href="../../Macaulay2Doc/html/___List.html">list</a></span></span></li>
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<div class="single"><h2>Description</h2>
<div><p>Computes a list L of possible denominators of Laurent monomials representing <a href="___First__Order__Deformation.html" title="The class of all first order deformations of monomial ideals.">FirstOrderDeformation</a>s of I. The list L is stratified into lists with ascending degree of the denominators. Each denominator is represented as a list of variables.</p>
<p>If the second argument v is given, one obtains only denominators contained (as a list) in v.</p>
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<table class="examples"><tr><td><pre>i1 : R=QQ[x_0..x_4];</pre>
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<tr><td><pre>i2 : I=ideal(x_0*x_1,x_1*x_2,x_2*x_3,x_3*x_4,x_4*x_0);
o2 : Ideal of R</pre>
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<tr><td><pre>i3 : possibleDenominators(I)
o3 = {{{x }, {x }, {x }, {x }, {x }}, {{x , x }, {x , x }, {x , x }, {x ,
0 1 2 3 4 0 1 1 2 2 3 0
------------------------------------------------------------------------
x }, {x , x }}}
4 3 4
o3 : List</pre>
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<tr><td><pre>i4 : possibleDenominators(I,{x_0,x_1,x_2});</pre>
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<div class="single"><h2>See also</h2>
<ul><li><span><a href="_deformations__Face.html" title="Compute the deformations associated to a face.">deformationsFace</a> -- Compute the deformations associated to a face.</span></li>
<li><span><a href="_deform.html" title="Compute the deformations associated to a Stanley-Reisner complex.">deform</a> -- Compute the deformations associated to a Stanley-Reisner complex.</span></li>
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<div class="waystouse"><h2>Ways to use <tt>possibleDenominators</tt> :</h2>
<ul><li>possibleDenominators(Ideal)</li>
<li>possibleDenominators(Ideal,List)</li>
<li>possibleDenominators(List,List)</li>
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