mirror of
https://github.com/kalmarek/Groups.jl.git
synced 2024-11-19 14:35:28 +01:00
32 lines
875 B
Julia
32 lines
875 B
Julia
import AbstractAlgebra
|
|
using GroupsCore
|
|
|
|
# disambiguation
|
|
GroupsCore.order(
|
|
::Type{I},
|
|
G::AbstractAlgebra.Generic.SymmetricGroup,
|
|
) where {I<:Integer} = I(factorial(G.n))
|
|
|
|
# disambiguation
|
|
GroupsCore.order(
|
|
::Type{I},
|
|
g::AbstractAlgebra.Generic.Perm,
|
|
) where {I<:Integer} =
|
|
I(foldl(lcm, length(c) for c in AbstractAlgebra.cycles(g)))
|
|
|
|
# correct the AA length:
|
|
Base.length(G::AbstractAlgebra.Generic.SymmetricGroup) = order(Int, G)
|
|
|
|
# genuinely new methods:
|
|
Base.IteratorSize(::Type{<:AbstractAlgebra.AbstractPermutationGroup}) = Base.HasLength()
|
|
|
|
function GroupsCore.gens(G::AbstractAlgebra.Generic.SymmetricGroup{I}) where {I}
|
|
a, b = one(G), one(G)
|
|
circshift!(a.d, b.d, -1)
|
|
b.d[1], b.d[2] = 2, 1
|
|
return [a, b]
|
|
end
|
|
|
|
Base.deepcopy_internal(g::AbstractAlgebra.Generic.Perm, ::IdDict) =
|
|
AbstractAlgebra.Generic.Perm(deepcopy(g.d), false)
|