OO -- the structure sheaf

Synopsis

• Usage:

  OO_X

• Inputs:
  • X, a variety
• Outputs:
  • the structure sheaf of X.

Description

i1 : R = QQ[x,y,z]/(y^2*z-x*(x-z)*(x-37*z));

i2 : X = Proj R

o2 = X

o2 : ProjectiveVariety

i3 : OO_X

o3 = OO
       X

o3 : SheafOfRings

i4 : HH^1(OO_X)

       1
o4 = QQ

o4 : QQ-module, free

i5 : HH^0(OO_X(3))

       9
o5 = QQ

o5 : QQ-module, free

See also

• CoherentSheaf -- the class of all coherent sheaves
• cohomology -- general cohomology functor