CoherentSheaf ZZ -- canonical twist of a coherent sheaf

CoherentSheaf ZZ -- canonical twist of a coherent sheaf

Synopsis:

Operator: symbol " " -- blank operator for adjacent expressions

Input:

an instance of class CoherentSheaf.

an instance of class ZZ.

Output:

an instance of class CoherentSheaf.

F(n) -- twist a coherent sheaf F on a projective variety by the n-th power of the hyperplane line bundle.

i1 : X = Proj(QQ[x,y,z])



o1 = X



o1 : ProjectiveVariety

i2 : F = OO_X



o2 = OO

       X



o2 : SheafOfRings

i3 : G = F(3)



        1

o3 = OO  (3)

       X



o3 : coherent sheaf on X, free

i4 : module G



                 1

o4 = QQ [x, y, z]



o4 : QQ [x, y, z]-module, free, degrees {-3}

i5 : degrees oo



o5 = {{-3}}



o5 : List

Code:

     -- ../../../Macaulay2/m2/varieties.m2:123
     CoherentSheaf ZZ := CoherentSheaf => (F,n) -> sheaf(variety F, F.module ** (ring F)^{n})