Add docs and tests for infinite graph

src/infinite_regular_factorgraph.jl

@@ -7,7 +7,12 @@ struct InfiniteRegularFactorGraph{T<:Integer} <: AbstractFactorGraph{T}
     kᵢ :: T   # variable degree
     kₐ :: T   # factor degree
 
-    function InfiniteRegularFactorGraph(kₐ::T, kᵢ::T) where {T<:Integer}
+    @doc """
+        InfiniteRegularFactorGraph(kᵢ, kₐ)
+
+    Construct an `InfiniteRegularFactorGraph` with variable degree `kᵢ` and factor degree `kₐ`
+    """
+    function InfiniteRegularFactorGraph(kᵢ::T, kₐ::T) where {T<:Integer}
         kᵢ > 0 || throw(ArgumentError("Factor degree must be positive, got $kᵢ"))
         kₐ > 0 || throw(ArgumentError("Factor degree must be positive, got $kₐ"))
         return new{T}(kᵢ, kₐ)
@@ -33,5 +38,20 @@ end
 function IndexedGraphs.neighbors(g::InfiniteRegularFactorGraph, ::FactorGraphVertex{Variable})
     return Fill(1, g.kᵢ)
 end
+
 edge_indices(g::InfiniteRegularFactorGraph, ::FactorGraphVertex{Factor}) = Fill(1, g.kₐ)
-edge_indices(g::InfiniteRegularFactorGraph, ::FactorGraphVertex{Variable}) = Fill(1, g.kᵢ)
+edge_indices(g::InfiniteRegularFactorGraph, ::FactorGraphVertex{Variable}) = Fill(1, g.kᵢ)
+
+function IndexedGraphs.inedges(g::InfiniteRegularFactorGraph, ::FactorGraphVertex{Factor})
+    return (IndexedEdge(1,1,1) for _ in 1:g.kₐ)
+end
+function IndexedGraphs.inedges(g::InfiniteRegularFactorGraph, ::FactorGraphVertex{Variable})
+    return (IndexedEdge(1,1,1) for _ in 1:g.kᵢ)
+
+end
+function IndexedGraphs.outedges(g::InfiniteRegularFactorGraph, ::FactorGraphVertex{Factor})
+    return (IndexedEdge(1,1,1) for _ in 1:g.kₐ)
+end
+function IndexedGraphs.outedges(g::InfiniteRegularFactorGraph, ::FactorGraphVertex{Variable})
+    return (IndexedEdge(1,1,1) for _ in 1:g.kᵢ)
+end

test/infinite_regular_factorgraph.jl

@@ -0,0 +1,25 @@
+kᵢ = 3
+kₐ = 4
+g = InfiniteRegularFactorGraph(kᵢ, kₐ)
+
+@testset "Basics" begin
+    @test degree(g, variable(100)) == kᵢ
+    @test degree(g, factor(12)) == kₐ
+    @test nfactors(g) == 1
+    @test nvariables(g) == 1
+    @test ne(g) == 1
+    @test variables(g) == 1:1
+    @test factors(g) == 1:1
+    @test all(edges(g)) do (i, j, id)
+        i == 1 && j == 1 && id == 1
+    end
+end
+
+@testset "Edge indices" begin
+    @test all(variables(g)) do i
+        idx.(collect(inedges(g, variable(i)))) == edge_indices(g, variable(i))
+    end
+    @test all(factors(g)) do a
+        idx.(collect(outedges(g, factor(a)))) == edge_indices(g, factor(a))
+    end
+end

test/runtests.jl

@@ -12,9 +12,8 @@ using Random
     Aqua.test_ambiguities(FactorGraphs)
 end
 
-@testset "FactorGraphs" begin
-    include("factorgraph.jl")
-    include("generators.jl")
-end
+include("factorgraph.jl")
+include("generators.jl")
+include("infinite_regular_factorgraph.jl")
 
 nothing