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<head><title>new ChainComplex -- make a new chain complex from scratch</title>
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<div><h1>new ChainComplex -- make a new chain complex from scratch</h1>
<div class="single"><h2>Description</h2>
<div><tt>C = new ChainComplex</tt> -- make a new chain complex.<p/>
The new chain complex is initialized with a differential of degree <tt>-1</tt> accessible as <tt>C.dd</tt> and of type <a href="___Chain__Complex__Map.html" title="the class of all maps between chain complexes">ChainComplexMap</a>. You can take the new chain complex and fill in the ring, the modules, and the differentials.<table class="examples"><tr><td><pre>i1 : C = new ChainComplex;</pre>
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<tr><td><pre>i2 : C.ring = ZZ;</pre>
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<tr><td><pre>i3 : C#2 = ZZ^1;</pre>
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<tr><td><pre>i4 : C#3 = ZZ^2;</pre>
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<tr><td><pre>i5 : C.dd#3 = matrix {{3,-11}};
1 2
o5 : Matrix ZZ <--- ZZ</pre>
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<tr><td><pre>i6 : C
1 2
o6 = ZZ <-- ZZ
2 3
o6 : ChainComplex</pre>
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<tr><td><pre>i7 : C.dd
1 2
o7 = 2 : ZZ <------------- ZZ : 3
| 3 -11 |
o7 : ChainComplexMap</pre>
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