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minimalCurveBetti -- computes the Betti diagram of the minimal curve

Description

A finite length module M determines a unique biliaison class. Curves of minimal degrees in this class are called minimal curves. Given the ideal of a curve J, this function returns the Betti tally of any minimal curve of J. Given a finite length module M, this function returns the Betti tally of any minimal curve in the biliaison class specified by M.

Synopsis

i1 : R = ZZ/101[x,y,z,w];
i2 : M = coker vars R;
i3 : I = minimalCurveBetti M

            0 1 2 3
o3 = total: 1 4 4 1
         0: 1 . . .
         1: . 4 4 1

o3 : BettiTally

Synopsis

  • Usage:
    T = minimalCurve(J)
  • Inputs:
    • J, an ideal, of a pure dimension one subscheme
  • Outputs:
    • T, a Betti tally, of a minimal curve in the biliaison class
i4 : R = ZZ/101[x,y,z,w];
i5 : J = monomialCurveIdeal(R,{1,3,4});

o5 : Ideal of R
i6 : I = minimalCurveBetti J

            0 1 2 3
o6 = total: 1 4 4 1
         0: 1 . . .
         1: . 4 4 1

o6 : BettiTally

See also

Ways to use minimalCurveBetti:

For the programmer

The object minimalCurveBetti is a method function.