specialCubicFourfold(String,Ring) -- random special cubic fourfold of a given type

Synopsis

Function: specialCubicFourfold
Usage:

specialCubicFourfold(n,K)

specialCubicFourfold n
Inputs:
- n, a string, the name of some known type of cubic fourfolds
- K, a ring, the coefficient ring
Optional inputs:
- InputCheck => ..., default value 1, make a special cubic fourfold
- NumNodes => ..., default value null, make a special cubic fourfold
- Verbose => ..., default value false, request verbose feedback
Outputs:
- a special cubic fourfold, a random special cubic fourfold of the indicated type over K

Description

i1 : X = specialCubicFourfold("3-nodal septic scroll",ZZ/65521);

o1 : ProjectiveVariety, cubic fourfold containing a surface of degree 7 and sectional genus 0

i2 : describe X

o2 = Special cubic fourfold of discriminant 26
     containing a 3-nodal surface of degree 7 and sectional genus 0
     cut out by 13 hypersurfaces of degree 3

Ways to use this method: