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SegreClasses :: segre

segre -- This method computes the Segre class of a scheme X inside a scheme Y, where X,Y are subschemes of some product of projective spaces

Synopsis

Description

For subschemes X,Y of ℙn1x...xℙnm this command computes the Segre class s(X,Y) of X in Y as a class in the Chow ring of ℙn1x...xℙnm.

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)
segre(X,D)
A = makeChowRing(R)
s = segre(X,D,A)

Ways to use segre :