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ChainComplexExtras :: prependZeroMap

prependZeroMap -- prepend a zero map to chain complex

Synopsis

Description

Add a zero map before the first differential in a chain complex.

i1 : S=ZZ/101[x,y]/ideal(x*y)

o1 = S

o1 : QuotientRing
i2 : C=chainComplex(matrix{{x}},matrix{{y}}**S^{ -1},matrix{{x}}**S^{ -2})[1]

      1      1      1      1
o2 = S  <-- S  <-- S  <-- S
                           
     -1     0      1      2

o2 : ChainComplex
i3 : prependZeroMap C

             1      1      1      1
o3 = 0  <-- S  <-- S  <-- S  <-- S
                                  
     -2     -1     0      1      2

o3 : ChainComplex
i4 : appendZeroMap C

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

o4 : ChainComplex

Ways to use prependZeroMap :

For the programmer

The object prependZeroMap is a method function.