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<head><title>isCommutative -- whether a ring is commutative</title>
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<div><h1>isCommutative -- whether a ring is commutative</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>isCommutative 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 the <a href="___Ring.html">ring</a> <tt>R</tt> is commutative and <a href="_false.html" title="">false</a> otherwise</span></li>
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<div class="single"><h2>Description</h2>
<div><table class="examples"><tr><td><pre>i1 : isCommutative(QQ[x,y])
o1 = true</pre>
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<tr><td><pre>i2 : isCommutative(QQ[x,y, SkewCommutative => true])
o2 = false</pre>
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<tr><td><pre>i3 : isCommutative(QQ[x,dx, WeylAlgebra => {x => dx}])
o3 = false</pre>
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<div class="single"><h2>See also</h2>
<ul><li><span><a href="___Weyl__Algebra.html" title="name for an optional argument">WeylAlgebra</a> -- name for an optional argument</span></li>
<li><span><a href="_monoid.html" title="make or retrieve a monoid">SkewCommutative</a> -- make or retrieve a monoid</span></li>
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<div class="waystouse"><h2>Ways to use <tt>isCommutative</tt> :</h2>
<ul><li>isCommutative(Ring)</li>
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