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mirror of https://github.com/kalmarek/Groups.jl.git synced 2024-10-15 07:20:35 +02:00

replace DirectProduct -> DirectPower

This commit is contained in:
kalmarek 2019-01-02 10:30:25 +01:00
parent c72067ec37
commit 38e327c385
3 changed files with 67 additions and 69 deletions

View File

@ -1,4 +1,4 @@
export DirectProductGroup, DirectProductGroupElem
export DirectPowerGroup, DirectPowerGroupElem
export MultiplicativeGroup, MltGrp, MltGrpElem
export AdditiveGroup, AddGrp, AddGrpElem
@ -75,8 +75,6 @@ elements(G::AddGrp{F}) where F <: AbstractAlgebra.GFField = (G((i-1)*G.obj(1)) f
order(G::MltGrp{<:AbstractAlgebra.GFField}) = order(G.obj) - 1
elements(G::MltGrp{F}) where F <: AbstractAlgebra.GFField = (G(i*G.obj(1)) for i in 1:order(G))
length(G::Union{AddGrp, MltGrp}) = order(G)
function iterate(G::AddGrp, s=0)
if s >= order(G)
return nothing
@ -100,21 +98,21 @@ end
###############################################################################
#
# DirectProductGroup / DirectProductGroupElem
# DirectPowerGroup / DirectPowerGroupElem
#
###############################################################################
@doc doc"""
DirectProductGroup(G::Group, n::Int) <: Group
DirectPowerGroup(G::Group, n::Int) <: Group
Implements `n`-fold direct product of `G`. The group operation is
`*` distributed component-wise, with component-wise identity as neutral element.
"""
struct DirectProductGroup{T<:Group} <: Group
struct DirectPowerGroup{T<:Group} <: Group
group::T
n::Int
end
struct DirectProductGroupElem{T<:GroupElem} <: GroupElem
struct DirectPowerGroupElem{T<:GroupElem} <: GroupElem
elts::Vector{T}
end
@ -124,14 +122,14 @@ end
#
###############################################################################
elem_type(::Type{DirectProductGroup{T}}) where {T} =
DirectProductGroupElem{elem_type(T)}
elem_type(::Type{DirectPowerGroup{T}}) where {T} =
DirectPowerGroupElem{elem_type(T)}
parent_type(::Type{DirectProductGroupElem{T}}) where {T} =
DirectProductGroup{parent_type(T)}
parent_type(::Type{DirectPowerGroupElem{T}}) where {T} =
DirectPowerGroup{parent_type(T)}
parent(g::DirectProductGroupElem) =
DirectProductGroup(parent(first(g.elts)), length(g.elts))
parent(g::DirectPowerGroupElem) =
DirectPowerGroup(parent(first(g.elts)), length(g.elts))
###############################################################################
#
@ -139,45 +137,45 @@ parent(g::DirectProductGroupElem) =
#
###############################################################################
size(g::DirectProductGroupElem) = size(g.elts)
Base.IndexStyle(::Type{DirectProductGroupElem}) = Base.LinearFast()
Base.getindex(g::DirectProductGroupElem, i::Int) = g.elts[i]
size(g::DirectPowerGroupElem) = size(g.elts)
Base.IndexStyle(::Type{DirectPowerGroupElem}) = Base.LinearFast()
Base.getindex(g::DirectPowerGroupElem, i::Int) = g.elts[i]
function Base.setindex!(g::DirectProductGroupElem{T}, v::T, i::Int) where {T}
function Base.setindex!(g::DirectPowerGroupElem{T}, v::T, i::Int) where {T}
parent(v) == parent(g.elts[i]) || throw(DomainError(
"$g is not an element of $i-th factor of $(parent(G))"))
g.elts[i] = v
return g
end
function Base.setindex!(g::DirectProductGroupElem{T}, v::S, i::Int) where {T, S}
function Base.setindex!(g::DirectPowerGroupElem{T}, v::S, i::Int) where {T, S}
g.elts[i] = parent(g.elts[i])(v)
return g
end
###############################################################################
#
# DirectProductGroup / DirectProductGroupElem constructors
# DirectPowerGroup / DirectPowerGroupElem constructors
#
###############################################################################
function pow(G::Group, H::Group)
function DirectPower(G::Group, H::Group)
G == H || throw(DomainError(
"Direct Powers are defined only for the same groups"))
return DirectProductGroup(G,2)
return DirectPowerGroup(G,2)
end
pow(H::Group, G::DirectProductGroup) = pow(G,H)
DirectPower(H::Group, G::DirectPowerGroup) = DirectPower(G,H)
function pow(G::DirectProductGroup, H::Group)
function DirectPower(G::DirectPowerGroup, H::Group)
G.group == H || throw(DomainError(
"Direct products are defined only for the same groups"))
return DirectProductGroup(G.group,G.n+1)
return DirectPowerGroup(G.group,G.n+1)
end
function pow(R::T, n::Int) where {T<:AbstractAlgebra.Ring}
@warn "Creating DirectProduct of the multilplicative group!"
return DirectProductGroup(R, n)
function DirectPower(R::AbstractAlgebra.Ring, n::Int)
@warn "Creating DirectPower of the multilplicative group!"
return DirectPowerGroup(R, n)
end
###############################################################################
@ -187,25 +185,25 @@ end
###############################################################################
@doc doc"""
(G::DirectProductGroup)(a::Vector, check::Bool=true)
(G::DirectPowerGroup)(a::Vector, check::Bool=true)
> Constructs element of the $n$-fold direct product group `G` by coercing each
> element of vector `a` to `G.group`. If `check` flag is set to `false` neither
> check on the correctness nor coercion is performed.
"""
function (G::DirectProductGroup)(a::Vector, check::Bool=true)
function (G::DirectPowerGroup)(a::Vector, check::Bool=true)
if check
G.n == length(a) || throw(DomainError(
"Can not coerce to DirectProductGroup: lengths differ"))
"Can not coerce to DirectPowerGroup: lengths differ"))
a = (G.group).(a)
end
return DirectProductGroupElem(a)
return DirectPowerGroupElem(a)
end
(G::DirectProductGroup)() = DirectProductGroupElem([G.group() for _ in 1:G.n])
(G::DirectPowerGroup)() = DirectPowerGroupElem([G.group() for _ in 1:G.n])
(G::DirectProductGroup)(g::DirectProductGroupElem) = G(g.elts)
(G::DirectPowerGroup)(g::DirectPowerGroupElem) = G(g.elts)
(G::DirectProductGroup)(a::Vararg{T, N}) where {T, N} = G([a...])
(G::DirectPowerGroup)(a::Vararg{T, N}) where {T, N} = G([a...])
###############################################################################
#
@ -213,12 +211,12 @@ end
#
###############################################################################
function hash(G::DirectProductGroup, h::UInt)
return hash(G.group, hash(G.n, hash(DirectProductGroup,h)))
function hash(G::DirectPowerGroup, h::UInt)
return hash(G.group, hash(G.n, hash(DirectPowerGroup,h)))
end
function hash(g::DirectProductGroupElem, h::UInt)
return hash(g.elts, hash(parent(g), hash(DirectProductGroupElem, h)))
function hash(g::DirectPowerGroupElem, h::UInt)
return hash(g.elts, hash(parent(g), hash(DirectPowerGroupElem, h)))
end
###############################################################################
@ -227,11 +225,11 @@ end
#
###############################################################################
function show(io::IO, G::DirectProductGroup)
function show(io::IO, G::DirectPowerGroup)
print(io, "$(G.n)-fold direct product of $(G.group)")
end
function show(io::IO, g::DirectProductGroupElem)
function show(io::IO, g::DirectPowerGroupElem)
print(io, "[$(join(g.elts,","))]")
end
@ -242,20 +240,20 @@ end
###############################################################################
@doc doc"""
==(g::DirectProductGroup, h::DirectProductGroup)
==(g::DirectPowerGroup, h::DirectPowerGroup)
> Checks if two direct product groups are the same.
"""
function (==)(G::DirectProductGroup, H::DirectProductGroup)
function (==)(G::DirectPowerGroup, H::DirectPowerGroup)
G.group == H.group || return false
G.n == G.n || return false
return true
end
@doc doc"""
==(g::DirectProductGroupElem, h::DirectProductGroupElem)
==(g::DirectPowerGroupElem, h::DirectPowerGroupElem)
> Checks if two direct product group elements are the same.
"""
function (==)(g::DirectProductGroupElem, h::DirectProductGroupElem)
function (==)(g::DirectPowerGroupElem, h::DirectPowerGroupElem)
g.elts == h.elts || return false
return true
end
@ -267,26 +265,26 @@ end
###############################################################################
@doc doc"""
*(g::DirectProductGroupElem, h::DirectProductGroupElem)
*(g::DirectPowerGroupElem, h::DirectPowerGroupElem)
> Return the direct-product group operation of elements, i.e. component-wise
> operation as defined by `operations` field of the parent object.
"""
function *(g::DirectProductGroupElem, h::DirectProductGroupElem, check::Bool=true)
function *(g::DirectPowerGroupElem, h::DirectPowerGroupElem, check::Bool=true)
if check
parent(g) == parent(h) || throw(DomainError(
"Can not multiply elements of different groups!"))
end
return DirectProductGroupElem([a*b for (a,b) in zip(g.elts,h.elts)])
return DirectPowerGroupElem([a*b for (a,b) in zip(g.elts,h.elts)])
end
^(g::DirectProductGroupElem, n::Integer) = Base.power_by_squaring(g, n)
^(g::DirectPowerGroupElem, n::Integer) = Base.power_by_squaring(g, n)
@doc doc"""
inv(g::DirectProductGroupElem)
inv(g::DirectPowerGroupElem)
> Return the inverse of the given element in the direct product group.
"""
function inv(g::DirectProductGroupElem{T}) where {T<:GroupElem}
return DirectProductGroupElem([inv(a) for a in g.elts])
function inv(g::DirectPowerGroupElem{T}) where {T<:GroupElem}
return DirectPowerGroupElem([inv(a) for a in g.elts])
end
###############################################################################
@ -313,20 +311,20 @@ function iterate(DPIter::DirectPowerIter, state=0)
return nothing
end
idx = Tuple(CartesianIndices(ntuple(i -> DPIter.orderG, DPIter.N))[state+1])
return DirectProductGroupElem([DPIter.elts[i] for i in idx]), state+1
return DirectPowerGroupElem([DPIter.elts[i] for i in idx]), state+1
end
eltype(::Type{DirectPowerIter{GrEl}}) where {GrEl} = DirectProductGroupElem{GrEl}
eltype(::Type{DirectPowerIter{GrEl}}) where {GrEl} = DirectPowerGroupElem{GrEl}
@doc doc"""
elements(G::DirectProductGroup)
elements(G::DirectPowerGroup)
> Returns `generator` that produces all elements of group `G` (provided that
> `G.group` implements the `elements` method).
"""
elements(G::DirectProductGroup) = DirectPowerIter(G.group, G.n)
elements(G::DirectPowerGroup) = DirectPowerIter(G.group, G.n)
@doc doc"""
order(G::DirectProductGroup)
order(G::DirectPowerGroup)
> Returns the order (number of elements) in the group.
"""
order(G::DirectProductGroup) = order(G.group)^G.n
order(G::DirectPowerGroup) = order(G.group)^G.n

View File

@ -72,7 +72,7 @@ include("FreeGroup.jl")
include("FPGroups.jl")
include("AutGroup.jl")
include("DirectProducts.jl")
include("DirectPower.jl")
include("WreathProducts.jl")
###############################################################################

View File

@ -20,21 +20,21 @@ export WreathProduct, WreathProductElem
* `P::Generic.PermGroup` : full `PermutationGroup`
"""
struct WreathProduct{T<:Group, I<:Integer} <: Group
N::DirectProductGroup{T}
N::DirectPowerGroup{T}
P::Generic.PermGroup{I}
function WreathProduct{T, I}(Gr::T, P::Generic.PermGroup{I}) where {T, I}
N = DirectProductGroup(Gr, Int(P.n))
N = DirectPowerGroup(Gr, Int(P.n))
return new(N, P)
end
end
struct WreathProductElem{T<:GroupElem, I<:Integer} <: GroupElem
n::DirectProductGroupElem{T}
n::DirectPowerGroupElem{T}
p::Generic.perm{I}
# parent::WreathProduct
function WreathProductElem{T, I}(n::DirectProductGroupElem{T}, p::Generic.perm{I},
function WreathProductElem{T, I}(n::DirectPowerGroupElem{T}, p::Generic.perm{I},
check::Bool=true) where {T, I}
if check
length(n.elts) == length(p.d) || throw(DomainError(
@ -65,7 +65,7 @@ parent(g::WreathProductElem) = WreathProduct(parent(g.n[1]), parent(g.p))
WreathProduct(G::T, P::Generic.PermGroup{I}) where {T, I} = WreathProduct{T, I}(G, P)
WreathProductElem(n::DirectProductGroupElem{T}, p::Generic.perm{I}, check=true) where {T,I} = WreathProductElem{T,I}(n, p, check)
WreathProductElem(n::DirectPowerGroupElem{T}, p::Generic.perm{I}, check=true) where {T,I} = WreathProductElem{T,I}(n, p, check)
###############################################################################
#
@ -88,11 +88,11 @@ function (G::WreathProduct)(g::WreathProductElem)
end
@doc doc"""
(G::WreathProduct)(n::DirectProductGroupElem, p::Generic.perm)
(G::WreathProduct)(n::DirectPowerGroupElem, p::Generic.perm)
> Creates an element of wreath product `G` by coercing `n` and `p` to `G.N` and
> `G.P`, respectively.
"""
(G::WreathProduct)(n::DirectProductGroupElem, p::Generic.perm) = WreathProductElem(n,p)
(G::WreathProduct)(n::DirectPowerGroupElem, p::Generic.perm) = WreathProductElem(n,p)
(G::WreathProduct)() = WreathProductElem(G.N(), G.P(), false)
@ -103,11 +103,11 @@ end
(G::WreathProduct)(p::Generic.perm) = G(G.N(), p)
@doc doc"""
(G::WreathProduct)(n::DirectProductGroupElem)
(G::WreathProduct)(n::DirectPowerGroupElem)
> Returns the image of `n` in `G` via embedding `n -> (n,())`. This is the
> embedding that makes sequence `1 -> N -> G -> P -> 1` exact.
"""
(G::WreathProduct)(n::DirectProductGroupElem) = G(n, G.P())
(G::WreathProduct)(n::DirectPowerGroupElem) = G(n, G.P())
(G::WreathProduct)(n,p) = G(G.N(n), G.P(p))
@ -163,7 +163,7 @@ end
#
###############################################################################
(p::perm)(n::DirectProductGroupElem) = DirectProductGroupElem(n.elts[p.d])
(p::perm)(n::DirectPowerGroupElem) = DirectPowerGroupElem(n.elts[p.d])
@doc doc"""
*(g::WreathProductElem, h::WreathProductElem)
@ -172,7 +172,7 @@ end
> `g*h = (g.n*g.p(h.n), g.p*h.p)`,
>
> where `g.p(h.n)` denotes the action of `g.p::Generic.perm` on
> `h.n::DirectProductGroupElem` via standard permutation of coordinates.
> `h.n::DirectPowerGroupElem` via standard permutation of coordinates.
"""
function *(g::WreathProductElem, h::WreathProductElem)
return WreathProductElem(g.n*g.p(h.n), g.p*h.p, false)