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dual(ChainComplexMap) -- dual of a chain complex

Synopsis

Function: dual
Usage:

dual C
Inputs:
- C, a chain complex map
Outputs:
- a chain complex map, the dual of the chain complex C

Description

i1 : R = QQ[a..f]

o1 = R

o1 : PolynomialRing

i2 : M = coker genericMatrix(R,a,2,3)

o2 = cokernel | a c e |
              | b d f |

                            2
o2 : R-module, quotient of R

i3 : res M

      2      3      1
o3 = R  <-- R  <-- R  <-- 0
                           
     0      1      2      3

o3 : ChainComplex

i4 : dual oo

             1      3      2
o4 = 0  <-- R  <-- R  <-- R
                           
     -3     -2     -1     0

o4 : ChainComplex

Ways to use this method:

dual(ChainComplexMap) -- dual of a chain complex