next | previous | forward | backward | up | top | index | toc | packages | Macaulay2 website
SpecialFanoFourfolds :: discriminant(SpecialCubicFourfold)

discriminant(SpecialCubicFourfold) -- discriminant of a special cubic fourfold

Synopsis

Description

This calculation passes through the determination of the topological Euler characteristic of the surface contained in the fourfold, which is obtained thanks to the functions EulerCharacteristic and Euler (the option Algorithm allows you to select the method).

i1 : X = specialCubicFourfold "quintic del Pezzo surface";

o1 : ProjectiveVariety, cubic fourfold containing a surface of degree 5 and sectional genus 1
i2 : time discriminant X
     -- used 0.0720453 seconds

o2 = 14

See also