next | previous | forward | backward | up | top | index | toc | Macaulay2 web site
DGAlgebras :: dgAlgebraMap

dgAlgebraMap -- Define a DG algebra map between DG algebras.

Synopsis

Description

i1 : R = ZZ/101[a,b,c]/ideal{a^3+b^3+c^3,a*b*c}

o1 = R

o1 : QuotientRing
i2 : K1 = koszulComplexDGA(ideal vars R,Variable=>"Y")

o2 = {Ring => R                          }
      Underlying algebra => R[Y , Y , Y ]
                               1   2   3
      Differential => {a, b, c}

o2 : DGAlgebra
i3 : K2 = koszulComplexDGA(ideal {b,c},Variable=>"T")

o3 = {Ring => R                      }
      Underlying algebra => R[T , T ]
                               1   2
      Differential => {b, c}

o3 : DGAlgebra
i4 : g = dgAlgebraMap(K1,K2,matrix{{Y_2,Y_3}})

o4 = map(R[Y , Y , Y ],R[T , T ],{Y , Y , a, b, c})
            1   2   3     1   2    2   3

o4 : DGAlgebraMap
i5 : isWellDefined g

o5 = true

The function does not check that the DG algebra map is well defined, however.

i6 : f = dgAlgebraMap(K2,K1,matrix{{0,T_1,T_2}})

o6 = map(R[T , T ],R[Y , Y , Y ],{0, T , T , a, b, c})
            1   2     1   2   3       1   2

o6 : DGAlgebraMap
i7 : isWellDefined f

o7 = false

Ways to use dgAlgebraMap :