Skip to content

Generalize monomials_of_degree to allow graded rings with grading group Z #4456

New issue

Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.

Sign up for GitHub

By clicking “Sign up for GitHub”, you agree to our terms of service and privacy statement. We’ll occasionally send you account related emails.

Already on GitHub? Sign in to your account

Merged
joschmitt merged 2 commits into from
Jan 14, 2025
Merged

Generalize monomials_of_degree to allow graded rings with grading group Z #4456

Show file tree
Hide file tree
Changes from all commits
Commits
Show all changes
2 commits
Select commit Hold shift + click to select a range
bcea90e
Generalize monomials_of_degree
paemurru Jan 12, 2025
ef6cd6c
Update src/InvariantTheory/iterators.jl
paemurru Jan 13, 2025
File filter

Filter by extension

Filter by extension
Conversations
Failed to load comments.
Loading
Jump to
Jump to file
Failed to load files.
Loading
Diff view
Diff view
3 changes: 2 additions & 1 deletion src/InvariantTheory/iterators.jl
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -53,7 +53,8 @@ function AllMonomials(R::MPolyDecRing, d::Int)
end

function AllMonomials(R::MPolyDecRing, d::Int, vars::Vector{Int})
@req is_standard_graded(R) "Iterator only implemented for the standard graded case"
@req is_z_graded(R) "Iterator only implemented when the grading group is Z"
@req all(isequal(ZZ(1)), map(i -> degree(R[i])[1], vars)) "Iterator only implemented for variables of degree 1"
return AllMonomials{typeof(R)}(R, d, vars)
end

Expand Down
4 changes: 4 additions & 0 deletions test/InvariantTheory/iterators.jl
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -9,4 +9,8 @@
@test collect(monomials_of_degree(R, 3, 1:1)) == [x^3]
@test isempty(monomials_of_degree(R, 2, Int[]))
end

R = graded_polynomial_ring(QQ, [:x, :y, :z], [1, 1, 3])[1]
x, y, z = gens(R)
@test collect(monomials_of_degree(R, 3, [1, 2])) == [x^3, x^2 * y, x * y^2, y^3]
end