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# removeZeroTrailingTerms -- remove trailing zero terms of a chain complex

## Synopsis

• Usage:
removeZeroTrailingTerms C
• Inputs:
• C, ,
• Outputs:

## Description

Remove trailing zero terms in a complex

 i1 : S=ZZ/101[x,y]/ideal(x*y) o1 = S o1 : QuotientRing i2 : C=prependZeroMap appendZeroMap chainComplex(matrix{{x}},matrix{{y}}**S^{ -1},matrix{{x}}**S^{ -2})[1] 1 1 1 1 o2 = 0 <-- S <-- S <-- S <-- S <-- 0 -2 -1 0 1 2 3 o2 : ChainComplex i3 : removeZeroTrailingTerms C 1 1 1 1 o3 = S <-- S <-- S <-- S -1 0 1 2 o3 : ChainComplex

If C has only one nonzero term, then the functions returns two zero maps.

 i4 : S=ZZ o4 = ZZ o4 : Ring i5 : C=prependZeroMap chainComplex( map(S^0,S^1,0))[3] 1 o5 = 0 <-- 0 <-- ZZ -4 -3 -2 o5 : ChainComplex i6 : removeZeroTrailingTerms C 1 o6 = 0 <-- ZZ <-- 0 -3 -2 -1 o6 : ChainComplex

## Ways to use removeZeroTrailingTerms :

• removeZeroTrailingTerms(ChainComplex)

## For the programmer

The object removeZeroTrailingTerms is .