For subschemes X, Y of ℙn1x...xℙnm this command computes a projective degree associated to h of a subscheme X in the subscheme Y as classes in the Chow ring of ℙn1x...xℙnm. The value returned is an integer. This method is faster if only one projective degree is needed.
R = makeProductRing({3,3}) |
x = gens(R) |
D = minors(2,matrix{{x_0..x_3},{x_4..x_7}}) |
X = ideal(x_0*x_1,x_1*x_2,x_0*x_2) |
A = makeChowRing(R) |
pd = projectiveDegrees(X,D,A) |
h=A_0^2*A_1^2 |
pdh=projectiveDegree(X,D,h) |
(sum pd)_h==pdh |