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<head><title>isAffineRing -- whether something is an affine ring</title>
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<div><h1>isAffineRing -- whether something is an affine ring</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>isAffineRing R</tt></div>
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<li><div class="single">Inputs:<ul><li><span><tt>R</tt>, <span>a <a href="___Ring.html">ring</a></span></span></li>
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<li><div class="single">Outputs:<ul><li><span><span>a <a href="___Boolean.html">Boolean value</a></span>, <a href="_true.html" title="">true</a> if <tt>R</tt> is an affine ring and <a href="_false.html" title="">false</a> otherwise</span></li>
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<div class="single"><h2>Description</h2>
<div>For our purposes, an affine ring is a quotient of a (not necessarily commutative) <a href="___Polynomial__Ring.html">polynomial ring</a> over a field.<table class="examples"><tr><td><pre>i1 : isAffineRing (ZZ[a,b,c,d])
o1 = false</pre>
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<tr><td><pre>i2 : isAffineRing (ZZ/101[a,b,c,d])
o2 = true</pre>
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<tr><td><pre>i3 : isAffineRing (ZZ/2[x,y,z]/(x^2-y*z))
o3 = true</pre>
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<tr><td><pre>i4 : isAffineRing (QQ[x,dx, WeylAlgebra => {x => dx}])
o4 = true</pre>
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<div class="single"><h2>See also</h2>
<ul><li><span><a href="_coefficient__Ring.html" title="get the coefficient ring">coefficientRing</a> -- get the coefficient ring</span></li>
<li><span><a href="_is__Field.html" title="whether something is a field">isField</a> -- whether something is a field</span></li>
<li><span><a href="_ambient.html" title="ambient free module of a subquotient, or ambient ring">ambient</a> -- ambient free module of a subquotient, or ambient ring</span></li>
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<div class="waystouse"><h2>Ways to use <tt>isAffineRing</tt> :</h2>
<ul><li>isAffineRing(PolynomialRing)</li>
<li>isAffineRing(QuotientRing)</li>
<li>isAffineRing(Ring)</li>
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