Merge pull request #50 from JuliaGraphs/dev

Add label listing utilities

src/MetaGraphsNext.jl

@@ -5,7 +5,8 @@ using Graphs
 using SimpleTraits
 
 export MetaGraph
-export label_for, code_for, labels
+export label_for, code_for
+export labels, edge_labels, neighbor_labels, outneighbor_labels, inneighbor_labels
 export set_data!
 export weighttype, default_weight, get_weight_function
 export MGFormat, DOTFormat

src/graphs.jl

@@ -47,6 +47,59 @@ function Base.issubset(meta_graph::MetaGraph, h::MetaGraph)
     return issubset(meta_graph.graph, h.graph)
 end
 
+## List labels
+
+"""
+    labels(meta_graph)
+
+Iterate through all vertex labels, in the same order as the codes obtained by `vertices(meta_graph)`.
+"""
+function labels(meta_graph::MetaGraph)
+    return (label_for(meta_graph, code) for code in vertices(meta_graph))
+end
+
+"""
+    edge_labels(meta_graph)
+
+Iterate through all tuples of edge labels, in the same order as the tuples of codes obtained by `edges(meta_graph)`.
+"""
+function edge_labels(meta_graph::MetaGraph)
+    return (
+        (label_for(meta_graph, src(ed)), label_for(meta_graph, dst(ed))) for
+        ed in edges(meta_graph)
+    )
+end
+
+"""
+    neighbor_labels(meta_graph, label)
+
+Iterate through all labels of neighbors of the vertex `code` with label `label`, in the same order as the codes obtained by `neighbors(meta_graph, code)`.
+"""
+function neighbor_labels(meta_graph::MetaGraph, label)
+    code_1 = code_for(meta_graph, label)
+    return (label_for(meta_graph, code_2) for code_2 in neighbors(meta_graph, code_1))
+end
+
+"""
+    outneighbor_labels(meta_graph, label)
+
+Iterate through all labels of outneighbors of the vertex `code` with label `label`, in the same order as the codes obtained by `outneighbors(meta_graph, code)`.
+"""
+function outneighbor_labels(meta_graph::MetaGraph, label)
+    code_1 = code_for(meta_graph, label)
+    return (label_for(meta_graph, code_2) for code_2 in outneighbors(meta_graph, code_1))
+end
+
+"""
+    inneighbor_labels(meta_graph, label)
+
+Iterate through all labels of inneighbors of the vertex `code` with label `label`, in the same order as the codes obtained by `inneighbors(meta_graph, code)`.
+"""
+function inneighbor_labels(meta_graph::MetaGraph, label)
+    code_2 = code_for(meta_graph, label)
+    return (label_for(meta_graph, code_1) for code_1 in inneighbors(meta_graph, code_2))
+end
+
 ## Set vertex and edge data
 
 """

src/metagraph.jl

@@ -251,12 +251,3 @@ This can be useful to interpret the results of methods inherited from `Graphs`.
 function label_for(meta_graph::MetaGraph, code::Integer)
     return meta_graph.vertex_labels[code]
 end
-
-"""
-    labels(meta_graph::MetaGraph)
-
-List all vertex labels, *not necessarily in the same order as the codes!*
-"""
-function labels(meta_graph::MetaGraph)
-    return values(meta_graph.vertex_labels)
-end

test/misc.jl

@@ -1,3 +1,42 @@
+function test_labels_codes(mg::MetaGraph)
+    for code in vertices(mg)
+        @test code_for(mg, label_for(mg, code)) == code
+    end
+    for label in labels(mg)
+        @test label_for(mg, code_for(mg, label)) == label
+    end
+    for (label_1, label_2) in edge_labels(mg)
+        @test has_edge(mg, code_for(mg, label_1), code_for(mg, label_2))
+    end
+    for label_1 in labels(mg)
+        for label_2 in outneighbor_labels(mg, label_1)
+            @test has_edge(mg, code_for(mg, label_1), code_for(mg, label_2))
+        end
+        for label_0 in inneighbor_labels(mg, label_1)
+            @test has_edge(mg, code_for(mg, label_0), code_for(mg, label_1))
+        end
+    end
+end
+
+@testset verbose = true "Coherence of labels and codes" begin
+    graph = Graph(Edge.([(1, 2), (1, 3), (2, 3)]))
+    vertices_description = [
+        :red => (255, 0, 0), :green => (0, 255, 0), :blue => (0, 0, 255)
+    ]
+    edges_description = [
+        (:red, :green) => :yellow, (:red, :blue) => :magenta, (:green, :blue) => :cyan
+    ]
+
+    colors = MetaGraph(graph, vertices_description, edges_description, "additive colors")
+    test_labels_codes(colors)
+
+    # Delete vertex in a copy and test again
+
+    colors_copy = copy(colors)
+    rem_vertex!(colors_copy, 1)
+    test_labels_codes(colors)
+end
+
 @testset verbose = true "Short-form add_vertex!/add_edge!" begin
     # short-form
     mg = MetaGraph(

test/tutorial/1_basics.jl

@@ -102,28 +102,18 @@ label_for(colors, 1)
 label_for(colors, 3)
 @test label_for(colors, 3) == :blue  #src
 
-# Test coherence  #src
+# ## Listing labels
 
-for label in labels(colors)  #src
-    @test label_for(colors, code_for(colors, label)) == label  #src
-end  #src
+# The functions `labels`, `edge_labels`, `(in/out)neighbor_labels` iterate through labels the same way that `vertices`, `edges` and `(in/out)neighbors` iterate through codes.
 
-for code in vertices(colors)  #src
-    @test code_for(colors, label_for(colors, code)) == code  #src
-end  #src
-
-# Delete vertex in a copy and test again  #src
-
-colors_copy = copy(colors)  #src
-rem_vertex!(colors_copy, 1)  #src
-
-for label in labels(colors_copy)  #src
-    @test label_for(colors_copy, code_for(colors_copy, label)) == label  #src
-end  #src
-
-for code in vertices(colors_copy)  #src
-    @test code_for(colors_copy, label_for(colors_copy, code)) == code  #src
-end  #src
+collect(labels(colors))
+@test collect(labels(colors)) == [:red, :green, :blue]  #src
+#-
+collect(edge_labels(colors))
+@test collect(edge_labels(colors)) == [(:red, :green), (:red, :blue), (:green, :blue)]  #src
+#-
+collect(neighbor_labels(colors, :red))
+@test collect(neighbor_labels(colors, :red)) == [:green, :blue]  #src
 
 # ## Handling weights