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ChainComplexExtras :: isExact

isExact -- Test to see if the ChainComplex is exact.

Synopsis

Description

i1 : R = ZZ/101[a,b,c]

o1 = R

o1 : PolynomialRing
i2 : k = coker vars R

o2 = cokernel | a b c |

                            1
o2 : R-module, quotient of R
i3 : kRes = res k

      1      3      3      1
o3 = R  <-- R  <-- R  <-- R  <-- 0
                                  
     0      1      2      3      4

o3 : ChainComplex
i4 : isExact kRes

o4 = false
i5 : trivialCx = chainComplex matrix {{1_R}}

      1      1
o5 = R  <-- R
             
     0      1

o5 : ChainComplex
i6 : isExact trivialCx

o6 = true

Ways to use isExact :

For the programmer

The object isExact is a method function with options.