Implement configuration model-like layer and simple_layer constructor

Co-Authored-By: Pietro Monticone <38562595+pitmonticone@users.noreply.github.com>
Co-Authored-By: Claudio Moroni <43729990+ClaudMor@users.noreply.github.com>

Author: 3 people

src/multilayerdigraph.jl

@@ -162,12 +162,6 @@ function MultilayerDiGraph(
         ),
     )
 
-    minimum(support(indegree_distribution)) >= 0 || throw(
-        ErrorException(
-            "Both the `indegree_distribution` and the `outdegree_distribution` must have positive support. Found $(support(indegree_distribution)) and $(support(outdegree_distribution)).",
-        ),
-    )
-
     empty_multilayerdigraph = MultilayerDiGraph(
         empty_layers,
         empty_interlayers;
@@ -177,23 +171,7 @@ function MultilayerDiGraph(
 
     n = nv(empty_multilayerdigraph)
 
-    indegree_sequence = Vector{Int64}(undef, n)
-    outdegree_sequence = Vector{Int64}(undef, n)
-    acceptable = false
-
-    @info "Trying to sample a digraphical sequence from the two provided distributions..."
-    while !acceptable
-        indegree_sequence .=
-            round.(Ref(Int), rand(indegree_distribution, nv(empty_multilayerdigraph)))
-        outdegree_sequence .=
-            round.(Ref(Int), rand(outdegree_distribution, nv(empty_multilayerdigraph)))
-
-        acceptable = all(0 .<= vcat(indegree_sequence, outdegree_sequence) .< n)
-
-        if acceptable
-            acceptable = isdigraphical(indegree_sequence, outdegree_sequence)
-        end
-    end
+    indegree_sequence,outdegree_sequence = sample_digraphical_degree_sequences(indegree_distribution,outdegree_distribution,n)
 
     return MultilayerDiGraph(
         empty_multilayerdigraph,

src/multilayergraph.jl

@@ -176,11 +176,6 @@ function MultilayerGraph(
         ),
     )
 
-    minimum(support(degree_distribution)) >= 0 || throw(
-        ErrorException(
-            "The `degree_distribution` must have positive support. Found $(support(degree_distribution)).",
-        ),
-    )
 
     empty_multilayergraph = MultilayerGraph(
         empty_layers,
@@ -191,19 +186,8 @@ function MultilayerGraph(
 
     n = nv(empty_multilayergraph)
 
-    degree_sequence = nothing
-    acceptable = false
-
-    while !acceptable
-        degree_sequence =
-            round.(Ref(Int), rand(degree_distribution, nv(empty_multilayergraph)))
+    degree_sequence = sample_graphical_degree_sequence(degree_distribution,n)
 
-        acceptable = all(0 .<= degree_sequence .< n)
-
-        if acceptable
-            acceptable = isgraphical(degree_sequence)
-        end
-    end
     return MultilayerGraph(
         empty_multilayergraph, degree_sequence; allow_self_loops=false, perform_checks=false
     )