[PartitionedGraphs] Small changes

Project.toml

@@ -1,7 +1,7 @@
 name = "NamedGraphs"
 uuid = "678767b0-92e7-4007-89e4-4527a8725b19"
 authors = ["Matthew Fishman <mfishman@flatironinstitute.org>, Joseph Tindall <jtindall@flatironinstitute.org> and contributors"]
-version = "0.8.2"
+version = "0.8.3"
 
 [deps]
 AbstractTrees = "1520ce14-60c1-5f80-bbc7-55ef81b5835c"

examples/Project.toml

@@ -4,4 +4,4 @@ NamedGraphs = "678767b0-92e7-4007-89e4-4527a8725b19"
 
 [compat]
 Graphs = "1.12.0"
-NamedGraphs = "0.8.1"
+NamedGraphs = "0.8.3"

src/NamedGraphs.jl

@@ -9,6 +9,7 @@ include("utils.jl")
 include("abstractnamededge.jl")
 include("namededge.jl")
 include("abstractnamedgraph.jl")
+include("abstractgraphindices.jl")
 include("decorate.jl")
 include("simplecycles.jl")
 include("shortestpaths.jl")

src/abstractgraphindices.jl

@@ -0,0 +1,32 @@
+using Graphs: AbstractEdge
+
+abstract type AbstractGraphIndices{T} end
+abstract type AbstractVertices{V} <: AbstractGraphIndices{V} end
+abstract type AbstractEdges{V, E <: AbstractEdge{V}} <: AbstractGraphIndices{E} end
+
+struct Vertices{V, Vs} <: AbstractVertices{V}
+    vertices::Vs
+    Vertices(vertices::Vs) where {Vs} = new{eltype(Vs), Vs}(vertices)
+end
+struct Edges{V, E <: AbstractEdge{V}, Es} <: AbstractEdges{V, E}
+    edges::Es
+    function Edges(edges::Es) where {Es}
+        E = eltype(Es)
+        return new{vertextype{E}, E, Es}(edges)
+    end
+end
+
+parent_graph_indices(vs::AbstractVertices) = vs.vertices
+parent_graph_indices(es::AbstractEdges) = es.edges
+
+# Interface
+Base.eltype(::Type{<:AbstractGraphIndices{T}}) where {T} = T
+
+Base.iterate(gi::AbstractGraphIndices) = iterate(parent_graph_indices(gi))
+Base.iterate(gi::AbstractGraphIndices, state) = iterate(parent_graph_indices(gi), state)
+Base.length(gi::AbstractGraphIndices) = length(parent_graph_indices(gi))
+
+Base.getindex(gi::AbstractGraphIndices, ind) = parent_graph_indices(gi)[ind]
+
+to_graph_indices(graph, indices) = indices
+to_graph_indices(graph, indices::Pair) = edgetype(graph)(indices)

src/abstractnamedgraph.jl

@@ -2,6 +2,7 @@ using Dictionaries: set!
 using Graphs:
     Graphs,
     AbstractGraph,
+    AbstractSimpleGraph,
     IsDirected,
     a_star,
     add_edge!,
@@ -34,7 +35,8 @@ using .GraphsExtensions:
     incident_edges,
     partition_vertices,
     rename_vertices,
-    subgraph
+    subgraph,
+    similar_graph
 using SimpleTraits: SimpleTraits, Not, @traitfn
 
 abstract type AbstractNamedGraph{V} <: AbstractGraph{V} end
@@ -45,6 +47,7 @@ abstract type AbstractNamedGraph{V} <: AbstractGraph{V} end
 
 Graphs.vertices(graph::AbstractNamedGraph) = not_implemented()
 position_graph(graph::AbstractNamedGraph) = not_implemented()
+position_graph(graph::AbstractSimpleGraph) = graph
 
 Graphs.rem_vertex!(graph::AbstractNamedGraph, vertex) = not_implemented()
 Graphs.add_vertex!(graph::AbstractNamedGraph, vertex) = not_implemented()
@@ -61,10 +64,12 @@ end
 # graph `position_graph(graph::AbstractNamedGraph)`.
 # Inverse map of `ordered_vertices`.
 vertex_positions(graph::AbstractNamedGraph) = not_implemented()
+vertex_positions(graph::AbstractSimpleGraph) = vertices(graph)
 
 # Outputs an object that when indexed by a vertex position
 # returns the corresponding vertex.
 ordered_vertices(graph::AbstractNamedGraph) = not_implemented()
+ordered_vertices(graph::AbstractSimpleGraph) = vertices(graph)
 
 Graphs.edgetype(graph::AbstractNamedGraph) = edgetype(typeof(graph))
 Graphs.edgetype(::Type{<:AbstractNamedGraph}) = not_implemented()
@@ -102,6 +107,7 @@ end
 #
 
 position_graph_type(graph::AbstractNamedGraph) = typeof(position_graph(graph))
+position_graph_type(T::Type{<:AbstractNamedGraph}) = Base.promote_op(position_graph, T)
 
 function Graphs.has_vertex(graph::AbstractNamedGraph, vertex)
     # TODO: `vertices` should have fast lookup!
@@ -112,16 +118,6 @@ Graphs.SimpleDiGraph(graph::AbstractNamedGraph) = SimpleDiGraph(position_graph(g
 
 Base.zero(G::Type{<:AbstractNamedGraph}) = G()
 
-# TODO: Implement using `copyto!`?
-function GraphsExtensions.directed_graph(graph::AbstractNamedGraph)
-    digraph = directed_graph_type(typeof(graph))(vertices(graph))
-    for e in edges(graph)
-        add_edge!(digraph, e)
-        add_edge!(digraph, reverse(e))
-    end
-    return digraph
-end
-
 # Default, can overload
 Base.eltype(graph::AbstractNamedGraph) = eltype(vertices(graph))
 
@@ -436,11 +432,20 @@ Graphs.is_connected(graph::AbstractNamedGraph) = is_connected(position_graph(gra
 Graphs.is_cyclic(graph::AbstractNamedGraph) = is_cyclic(position_graph(graph))
 
 @traitfn function Base.reverse(graph::AbstractNamedGraph::IsDirected)
-    return not_implemented()
+    return similar_graph(graph, vertices, map(reverse, collect(edges(graph))))
 end
 
+# This wont be the most efficient way for a given graph type.
 @traitfn function Base.reverse!(g::AbstractNamedGraph::IsDirected)
-    return not_implemented()
+
+    edge_list = collect(edges(g))
+
+    for edge in edge_list
+        rem_edge!(g, edge)
+        add_edge!(g, reverse(edge))
+    end
+
+    return g
 end
 
 # TODO: Move to `namedgraph.jl`, or make the output generic?
@@ -493,9 +498,7 @@ end
 # traversal algorithms.
 function Graphs.tree(graph::AbstractNamedGraph, parents)
     n = length(parents)
-    # TODO: Use `directed_graph` here to make more generic?
-    ## t = GenericNamedGraph(DiGraph(n), vertices(graph))
-    t = directed_graph_type(typeof(graph))(vertices(graph))
+    t = similar_graph(directed_graph_type(typeof(graph)), vertices(graph))
     for destination in eachindex(parents)
         source = parents[destination]
         if source != destination

src/lib/GraphsExtensions/src/abstractgraph.jl

@@ -47,18 +47,34 @@ undirected_graph_type(g::AbstractGraph) = undirected_graph_type(typeof(g))
 
 @traitfn directed_graph(graph::::IsDirected) = graph
 
-convert_vertextype(::Type{V}, graph::AbstractGraph{V}) where {V} = graph
-function convert_vertextype(V::Type, graph::AbstractGraph)
-    return not_implemented()
+convert_vertextype(::Type{V}, G::AbstractGraph{V}) where {V} = G
+convert_vertextype(::Type, ::AbstractGraph) = not_implemented()
+
+convert_vertextype(::Type{V}, G::Type{<:AbstractGraph{V}}) where {V} = G
+convert_vertextype(::Type, ::Type{<:AbstractGraph}) = not_implemented()
+
+similar_graph(graph::AbstractGraph) = similar_graph(typeof(graph))
+similar_graph(T::Type{<:AbstractGraph}) = T()
+
+function similar_graph(graph_or_type, vertices)
+    new_graph = similar_graph(graph_or_type)
+    add_vertices!(new_graph, vertices)
+    return new_graph
+end
+function similar_graph(graph_or_type, vertices, edges)
+    new_graph = similar_graph(graph_or_type, vertices)
+    add_edges!(new_graph, edges)
+    return new_graph
 end
 
-function graph_from_vertices(graph_type::Type{<:AbstractGraph}, vertices)
-    return graph_type(vertices)
+function similar_graph(graph::AbstractGraph, vertex_type::Type)
+    new_graph = convert_vertextype(vertex_type, similar_graph(typeof(graph)))
+    return new_graph
 end
 
 # TODO: Handle metadata in a generic way
 @traitfn function directed_graph(graph::::(!IsDirected))
-    digraph = graph_from_vertices(directed_graph_type(graph), vertices(graph))
+    digraph = similar_graph(directed_graph_type(graph), vertices(graph))
     for e in edges(graph)
         add_edge!(digraph, e)
         add_edge!(digraph, reverse(e))
@@ -74,7 +90,7 @@ end
 # to avoid method overwrite warnings, see:
 # https://github.com/mauro3/SimpleTraits.jl#method-overwritten-warnings
 @traitfn function undirected_graph(graph::::IsDirected)
-    undigraph = graph_from_vertices(undirected_graph_type(typeof(graph)), vertices(graph))
+    undigraph = similar_graph(undirected_graph_type(typeof(graph)), vertices(graph))
     for e in edges(graph)
         # TODO: Check for repeated edges?
         add_edge!(undigraph, e)

src/lib/GraphsExtensions/src/simplegraph.jl

@@ -5,8 +5,11 @@ function permute_vertices(graph::AbstractSimpleGraph, permutation)
 end
 
 # https://github.com/JuliaGraphs/Graphs.jl/issues/365
-function graph_from_vertices(graph_type::Type{<:AbstractSimpleGraph}, vertices)
-    @assert vertices == Base.OneTo(length(vertices))
+similar_graph(graph_type::Type{<:AbstractSimpleGraph}) = graph_type()
+function similar_graph(graph::AbstractSimpleGraph, vertices::Base.OneTo)
+    return similar_graph(typeof(graph), vertices)
+end
+function similar_graph(graph_type::Type{<:AbstractSimpleGraph}, vertices::Base.OneTo)
     return graph_type(length(vertices))
 end
 

src/lib/GraphsExtensions/test/runtests.jl

@@ -11,6 +11,7 @@ using AbstractTrees:
     rootindex
 using Dictionaries: Dictionary, Indices
 using Graphs:
+    AbstractGraph,
     add_edge!,
     add_vertex!,
     dst,
@@ -44,6 +45,7 @@ using NamedGraphs.GraphsExtensions:
     add_edge,
     add_edges,
     add_edges!,
+    add_vertices!,
     all_edges,
     arrange_edge,
     arranged_edges,
@@ -83,6 +85,7 @@ using NamedGraphs.GraphsExtensions:
     rem_edges!,
     rename_vertices,
     root_vertex,
+    similar_graph,
     subgraph,
     tree_graph_node,
     undirected_graph,
@@ -108,6 +111,7 @@ using Test: @test, @test_broken, @test_throws, @testset
 # - random_bfs_tree
 
 @testset "NamedGraphs.GraphsExtensions" begin
+
     # has_vertices
     g = path_graph(4)
     @test has_vertices(g, 1:3)
@@ -552,6 +556,23 @@ using Test: @test, @test_broken, @test_throws, @testset
     @test_throws ErrorException root_vertex(g)
     @test_throws MethodError root_vertex(binary_tree(3))
 
+    # similar_graph
+    g = path_graph(4)
+    @test similar_graph(g) isa typeof(g)
+    @test similar_graph(typeof(g)) isa typeof(g)
+    @test similar_graph(g, vertices(g), edges(g)) == g
+    @test !(similar_graph(g, vertices(g), edges(g)) === g)
+    sg = similar_graph(g, vertices(g))
+    @test vertices(sg) == vertices(g)
+    @test isempty(edges(sg))
+
+    struct Graph <: AbstractGraph{Int}
+        field
+    end
+
+    g = Graph(1)
+    @test_throws MethodError similar_graph(g)
+
     # add_edge
     g = SimpleGraph(4)
     add_edge!(g, 1 => 2)

src/lib/PartitionedGraphs/src/abstractpartitionedgraph.jl

@@ -2,6 +2,7 @@ using Dictionaries: Dictionary
 using Graphs:
     AbstractEdge,
     AbstractGraph,
+    AbstractSimpleGraph,
     Graphs,
     add_vertex!,
     dst,
@@ -11,23 +12,40 @@ using Graphs:
     rem_vertex!,
     src,
     vertices
-using ..NamedGraphs: NamedGraphs, AbstractNamedGraph, NamedGraph
+using ..NamedGraphs: NamedGraphs, AbstractNamedGraph, NamedGraph, NamedDiGraph
 using ..NamedGraphs.GraphsExtensions:
-    GraphsExtensions, add_vertices!, not_implemented, rem_vertices!, subgraph, vertextype
+    GraphsExtensions,
+    add_vertices!,
+    not_implemented,
+    rem_vertices!,
+    subgraph,
+    convert_vertextype
 
 # For you own graph type `g`, you should define a method for this function if you
 # desire custom partitioning.
 partitioned_vertices(g::AbstractGraph) = [vertices(g)]
 
+#TODO: Write this in terms of traits
+function similar_quotient_graph(g::AbstractGraph)
+    if is_directed(g)
+        sg = NamedDiGraph()
+    else
+        sg = NamedGraph()
+    end
+    return convert_vertextype(keytype(partitioned_vertices(g)), sg)
+end
+
 # For fast quotient edge checking and graph construction, one should overload this function.
 function quotient_graph(g::AbstractGraph)
 
-    qg = NamedGraph(keys(partitioned_vertices(g)))
+    qg = similar_quotient_graph(g)
+
+    add_vertices!(qg, keys(partitioned_vertices(g)))
 
     for e in edges(g)
         qv_src = parent(quotientvertex(g, src(e)))
         qv_dst = parent(quotientvertex(g, dst(e)))
-        qe = qv_src => qv_dst
+        qe = edgetype(qg)(qv_src => qv_dst)
         if qv_src != qv_dst && !has_edge(qg, qe)
             add_edge!(qg, qe)
         end
@@ -117,12 +135,6 @@ function unpartitioned_graph_type(pg::AbstractPartitionedGraph)
     return typeof(unpartitioned_graph(pg))
 end
 
-
-# AbstractGraph interface.
-function Graphs.is_directed(graph_type::Type{<:AbstractPartitionedGraph})
-    return is_directed(unpartitioned_graph_type(graph_type))
-end
-
 #Functions for the abstract type
 Graphs.vertices(pg::AbstractPartitionedGraph) = vertices(unpartitioned_graph(pg))
 Graphs.edges(pg::AbstractPartitionedGraph) = edges(unpartitioned_graph(pg))