next | previous | forward | backward | up | top | index | toc | Macaulay2 website
Macaulay2Doc :: new ChainComplex

new ChainComplex -- make a new chain complex from scratch

Description

C = new ChainComplex -- make a new chain complex.

The new chain complex is initialized with a differential of degree -1 accessible as C.dd and of type ChainComplexMap. You can take the new chain complex and fill in the ring, the modules, and the differentials.

i1 : C = new ChainComplex;
i2 : C.ring = ZZ;
i3 : C#2 = ZZ^1;
i4 : C#3 = ZZ^2;
i5 : C.dd#3 = matrix {{3,-11}};

              1        2
o5 : Matrix ZZ  <--- ZZ
i6 : C

       1       2
o6 = ZZ  <-- ZZ
              
     2       3

o6 : ChainComplex
i7 : C.dd

           1                  2
o7 = 2 : ZZ  <------------- ZZ  : 3
                | 3 -11 |

o7 : ChainComplexMap