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<head><title>isExact -- Test to see if the ChainComplex is exact.</title>
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<div><h1>isExact -- Test to see if the ChainComplex is exact.</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>isExact(F)</tt></div>
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<li><div class="single">Inputs:<ul><li><span><tt>F</tt>, </span></li>
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<li><div class="single">Outputs:<ul><li><span>Boolean</span></li>
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<div class="single"><h2>Description</h2>
<div><table class="examples"><tr><td><pre>i1 : R = ZZ/101[a,b,c]
o1 = R
o1 : PolynomialRing</pre>
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<tr><td><pre>i2 : k = coker vars R
o2 = cokernel | a b c |
1
o2 : R-module, quotient of R</pre>
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<tr><td><pre>i3 : kRes = res k
1 3 3 1
o3 = R <-- R <-- R <-- R <-- 0
0 1 2 3 4
o3 : ChainComplex</pre>
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<tr><td><pre>i4 : isExact kRes
o4 = false</pre>
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<tr><td><pre>i5 : trivialCx = chainComplex matrix {{1_R}}
1 1
o5 = R <-- R
0 1
o5 : ChainComplex</pre>
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<tr><td><pre>i6 : isExact trivialCx
o6 = true</pre>
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<div class="waystouse"><h2>Ways to use <tt>isExact</tt> :</h2>
<ul><li>isExact(ChainComplex)</li>
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