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isResolution -- test whether a chain complex resolves the quotient by a monomial ideal

Description

Returns true iff HH_0(C) = S/I (as a quotient module) and HH_i(C) = 0 for every i in the strict interior of C.

i1 : R = QQ[x,y,z]

o1 = R

o1 : PolynomialRing
i2 : I = monomialIdeal(x^3, x^2*y, x*y^2, y^3)

                     3   2      2   3
o2 = monomialIdeal (x , x y, x*y , y )

o2 : MonomialIdeal of R
i3 : isResolution(res I, I)

o3 = true
i4 : isResolution(EKResolution I, I)

o4 = true
i5 : isResolution(AHHResolution monomialIdeal(x*y, x*z, y*z),
                  monomialIdeal(x*y, x*z, y*z))

o5 = true

See also

Ways to use isResolution:

  • isResolution(ChainComplex,MonomialIdeal)

For the programmer

The object isResolution is a method function.


The source of this document is in /build/reproducible-path/macaulay2-1.26.06+ds/M2/Macaulay2/packages/ChainComplexExtras.m2:2166:0.