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DGAlgebras :: cycles

cycles -- Cycles chosen when computing the homology algebra of a DGAlgebra

Synopsis

Description

i1 : R = ZZ/101[a,b,c,d]/ideal{a^3,b^4,c^5,d^6}

o1 = R

o1 : QuotientRing
i2 : A = koszulComplexDGA(R)

o2 = {Ring => R                              }
      Underlying algebra => R[T , T , T , T ]
                               1   2   3   4
      Differential => {a, b, c, d}
      isHomogeneous => true

o2 : DGAlgebra
i3 : apply(maxDegree A + 1, i -> numgens prune homology(i,A))

o3 = {1, 4, 6, 4, 1}

o3 : List
i4 : HA = homologyAlgebra(A)
Computing generators in degree 1 :      -- used 0.00127305 seconds
Computing generators in degree 2 :      -- used 0.0090529 seconds
Computing generators in degree 3 :      -- used 0.00839003 seconds
Computing generators in degree 4 :      -- used 0.00766468 seconds
Finding easy relations           :      -- used 0.0143672 seconds
Computing relations in degree 1  :      -- used 0.00180939 seconds
Computing relations in degree 2  :      -- used 0.00182305 seconds
Computing relations in degree 3  :      -- used 0.00180589 seconds
Computing relations in degree 4  :      -- used 0.0017855 seconds
Computing relations in degree 5  :      -- used 0.00163217 seconds

o4 = HA

o4 : PolynomialRing
i5 : numgens HA

o5 = 4
i6 : HA.cache.cycles

       2     3     4     5
o6 = {a T , b T , c T , d T }
         1     2     3     4

o6 : List

For the programmer

The object cycles is a symbol.