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<head><title>isPurePower -- determine whether a ring element is a pure power of a variable</title>
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<div><h1>isPurePower -- determine whether a ring element is a pure power of a variable</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=isPurePower f</tt></div>
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<li><div class="single">Inputs:<ul><li><span><tt>f</tt>, <span>a <a href="../../Macaulay2Doc/html/___Ring__Element.html">ring element</a></span>, an element of a polynomial ring</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> if <tt>f</tt> is a nonzero power of a variable and <tt>false</tt> otherwise</span></li>
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<div class="single"><h2>Description</h2>
<div><div><tt>isPurePower</tt> tests a ring element in a polynomial ring to determine whether or not it is nonzero and a power of a variable. <tt>isPurePower</tt> is used in the lex-plus-powers <a href="___L__P__P.html" title="return the lex-plus-powers (LPP) ideal corresponding to a given Hilbert function and power sequence">LPP</a> code.</div>
<table class="examples"><tr><td><pre>i1 : R=ZZ/32003[a..c];</pre>
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<tr><td><pre>i2 : isPurePower a^4
o2 = true</pre>
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<tr><td><pre>i3 : isPurePower (a*b^5)
o3 = false</pre>
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<tr><td><pre>i4 : isPurePower (a^3-b^3)
o4 = false</pre>
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<div class="single"><h2>See also</h2>
<ul><li><span><a href="___L__P__P.html" title="return the lex-plus-powers (LPP) ideal corresponding to a given Hilbert function and power sequence">LPP</a> -- return the lex-plus-powers (LPP) ideal corresponding to a given Hilbert function and power sequence</span></li>
<li><span><a href="_is__L__P__P.html" title="determine whether an ideal is an LPP ideal">isLPP</a> -- determine whether an ideal is an LPP ideal</span></li>
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<div class="waystouse"><h2>Ways to use <tt>isPurePower</tt> :</h2>
<ul><li>isPurePower(RingElement)</li>
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