CoherentSheaf ZZ -- canonical twist of a coherent sheaf

CoherentSheaf ZZ -- canonical twist of a coherent sheaf

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 = Proj(QQ [x, y, z])



o1 : ProjectiveVariety

i2 : F = OO_X



                         1

o2 = sheaf((QQ [x, y, z]) )



o2 : CoherentSheaf

i3 : G = F(3)



                         1

o3 = sheaf((QQ [x, y, z]) )



o3 : CoherentSheaf

i4 : module G



                   1

o4 = (QQ [x, y, z])



o4 : QQ [x, y, z] - module, free

i5 : degrees oo



o5 = {{-3}}



o5 : List

Synopsis of use:

Operator:

Class of argument 1: CoherentSheaf

Class of argument 2: ZZ

Class of typical returned value: CoherentSheaf

Code:

     -- ../m2/varieties.m2:51
     CoherentSheaf ZZ := CoherentSheaf => (F,n) -> sheaf(F.module ** (ring F)^{n})