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M0nbar :: intersection(DivisorClassRepresentativeM0nbar,CurveClassRepresentativeM0nbar)

intersection(DivisorClassRepresentativeM0nbar,CurveClassRepresentativeM0nbar) -- intersection number of a divisor class and curve class

Synopsis

Description

The basic formula for intersecting a boundary divisor with an F-curve is found in Keel and McKernan's paper.

i1 : L1={ {{{2,1},{3},{4},{5}},-2}, {{{1,3},{2},{4},{5}},-7}, {{{1,4},{2},{3},{5}},1}};
i2 : C=curveClassRepresentativeM0nbar(5,L1);
i3 : L2={ {{1,3},1}, {{1,4},1}};
i4 : D=divisorClassRepresentativeM0nbar(5,L2);
i5 : intersection(D,C)

o5 = 6