(NewMethod,ChainComplex)

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

o7 = 1 : 0 <----- ZZ  : 2

              0

     

           1                  2

     2 : ZZ  <------------- ZZ  : 3

                | 3 -11 |



o7 : ChainComplexMap