next | previous | forward | backward | up | top | index | toc | Macaulay2 web site

SegreClasses :: makeProductRing

makeProductRing

Synopsis

Usage:
makeProductRing(n)
makeProductRing(kk,n)
Inputs:
- n, a list, a list n₁,...,n_m of the dimensions of the m projective spaces in the product ℙ^n₁x...xℙ^n_m.
- kk, a ring, the coefficient ring to be used
Outputs:
- a ring, the graded coordinate ring of ℙ^n₁x...xℙ^n_m.

Description

Builds the multi-graded coordinate ring of ℙ^n₁x...xℙ^n_m.

i1 : R = makeProductRing(QQ,{3,4})

o1 = R

o1 : PolynomialRing

i2 : R = makeProductRing({3,4})

o2 = R

o2 : PolynomialRing

i3 : degrees R

o3 = {{1, 0}, {1, 0}, {1, 0}, {1, 0}, {0, 1}, {0, 1}, {0, 1}, {0, 1}, {0, 1}}

o3 : List

i4 : gens R

o4 = {a, b, c, d, e, f, g, h, i}

o4 : List

Ways to use `makeProductRing` :

makeProductRing(List)
makeProductRing(Ring,List)
makeProductRing(Ring,Symbol,List) (missing documentation)
makeProductRing(Symbol,List) (missing documentation)