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Macaulay2Doc :: HH ChainComplex

HH ChainComplex -- homology of a chain complex

Synopsis

Description

i1 : R = QQ[x]/x^5;
i2 : C = res coker vars R

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

o2 : ChainComplex
i3 : M = HH C
-- ker (9) called with OptionTable: OptionTable{SubringLimit => infinity}
-- ker (9) returned CacheFunction: -*a cache function*-
-- ker (9) called with Matrix: {1} | x4 |
-- ker (9) returned Module: image {5} | x |
assert( ker(map(R^{{-1}},R^{{-5}},{{x^4}})) === (image(map(R^{{-5}},R^{{-6}},{{x}}))))

o3 = 0 : cokernel | x |                      

     1 : subquotient ({1} | x4 |, {1} | x4 |)

     2 : image {5} | x |                     

o3 : GradedModule
i4 : prune M

o4 = 0 : cokernel | x |     

     1 : 0                  

     2 : cokernel {6} | x4 |

o4 : GradedModule