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<head><title>chainComplex(Ring) -- make an empty chain complex over a ring</title>
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<div><h1>chainComplex(Ring) -- make an empty chain complex over a 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>chainComplex R</tt></div>
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<li><span>Function: <a href="_chain__Complex.html" title="make a chain complex">chainComplex</a></span></li>
<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="___Chain__Complex.html">chain complex</a></span>, an empty chain complex over <tt>R</tt></span></li>
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<div class="single"><h2>Description</h2>
<div>The resulting chain complex can be further populated with modules and maps.<table class="examples"><tr><td><pre>i1 : C = chainComplex ZZ
o1 = 0
o1 : ChainComplex</pre>
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<tr><td><pre>i2 : C.dd_101 = random(ZZ^2,ZZ^3)
o2 = | 6 2 3 |
| 8 1 9 |
2 3
o2 : Matrix ZZ <--- ZZ</pre>
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<tr><td><pre>i3 : C.dd_105 = id_(ZZ^2)
o3 = | 1 0 |
| 0 1 |
2 2
o3 : Matrix ZZ <--- ZZ</pre>
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<tr><td><pre>i4 : C
2 3 2 2
o4 = ZZ <-- ZZ <-- 0 <-- 0 <-- ZZ <-- ZZ
100 101 102 103 104 105
o4 : ChainComplex</pre>
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<tr><td><pre>i5 : C.dd
2 3
o5 = 100 : ZZ <------------- ZZ : 101
| 6 2 3 |
| 8 1 9 |
2 2
104 : ZZ <----------- ZZ : 105
| 1 0 |
| 0 1 |
o5 : ChainComplexMap</pre>
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