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Macaulay2Doc :: ChainComplexMap ^ ZZ

ChainComplexMap ^ ZZ -- iterated composition

Synopsis

Description

If f is a GradedModuleMap, then so is the result.

One use of this function is to determine if a chain complex is well-defined. The chain complex will be well-defined if the square of the differential is zero.

i1 : R = QQ[x,y,z];
i2 : C = res coker vars R

      1      3      3      1
o2 = R  <-- R  <-- R  <-- R  <-- 0
                                  
     0      1      2      3      4

o2 : ChainComplex
i3 : C.dd^2 == 0

o3 = true

See also