variety(Ideal)  the closed projective subvariety defined by an ideal
Synopsis

 Usage:
 variety I

Function: variety

Inputs:

I, an ideal, a homogeneous ideal

Outputs:

the closed subvariety defined by an ideal
Description
In the example, we compute the dimension of a line in the projective plane.
i1 : R = QQ[x..z]
o1 = R
o1 : PolynomialRing

i2 : variety ideal x
R
o2 = Proj()
x
o2 : ProjectiveVariety

i3 : dim oo
o3 = 1

Caveat
An alternative task for this function would be to define the affine subvariety, so if something like this eventually becomes useful, we may have to redesign it. Suggestions welcome.