Sbromberger/fix zeros

Project.toml

@@ -1,6 +1,6 @@
 name = "SimpleWeightedGraphs"
 uuid = "47aef6b3-ad0c-573a-a1e2-d07658019622"
-version = "1.1.1"
+version = "2.0.0"
 
 [deps]
 LightGraphs = "093fc24a-ae57-5d10-9952-331d41423f4d"

src/SimpleWeightedGraphs.jl

@@ -5,6 +5,7 @@ using LinearAlgebra
 using Markdown
 using SparseArrays
 
+using Base.Iterators
 import Base:
     convert, eltype, show, ==, Pair, Tuple, copy, length, issubset, zero
 
@@ -113,9 +114,11 @@ end
 
 function outneighbors(g::AbstractSimpleWeightedGraph, v::Integer)
     mat = g.weights
-    return view(mat.rowval, mat.colptr[v]:mat.colptr[v+1]-1)
+    return Iterators.filter(!iszero, view(mat.rowval, mat.colptr[v]:mat.colptr[v+1]-1))
 end
 
+outdegree(g::AbstractSimpleWeightedGraph, v::Integer) = length(outneighbors(g, v).itr)
+
 get_weight(g::AbstractSimpleWeightedGraph, u::Integer, v::Integer) = g.weights[v, u]
 
 zero(g::T) where T<:AbstractSimpleWeightedGraph = T()

src/simpleweighteddigraph.jl

@@ -38,7 +38,7 @@ SimpleWeightedDiGraph{T,U}(g::SimpleWeightedDiGraph) where {T <: Integer, U <: R
     SimpleWeightedDiGraph(SparseMatrixCSC{U, T}(copy(g.weights)), permute=false)
 
 
-ne(g::SimpleWeightedDiGraph) = nnz(g.weights)
+ne(g::SimpleWeightedDiGraph) = count(!iszero, nonzeros(g.weights))
 
 function SimpleWeightedDiGraph{T,U}(n::Integer = 0) where {T<:Integer, U<:Real}
     weights = spzeros(U, T, T(n), T(n))
@@ -78,14 +78,15 @@ function SimpleWeightedDiGraph(i::AbstractVector{T}, j::AbstractVector{T}, v::Ab
     SimpleWeightedDiGraph{T, U}(sparse(j, i, v, m, m, combine), permute=false)
 end
 
-LightGraphs.SimpleDiGraph(g::SimpleWeightedDiGraph) = SimpleDiGraph(g.weights)
+LightGraphs.SimpleDiGraph(g::SimpleWeightedDiGraph) = SimpleDiGraph(g.weights')
 
 edgetype(::SimpleWeightedDiGraph{T, U}) where T<:Integer where U<:Real = SimpleWeightedGraphEdge{T,U}
 
-edges(g::SimpleWeightedDiGraph) = (SimpleWeightedEdge(x[2], x[1], x[3]) for x in zip(findnz(g.weights)...))
+edges(g::SimpleWeightedDiGraph) = Iterators.filter(!iszero ∘ weight, SimpleWeightedEdge(x[2], x[1], x[3]) for x in zip(findnz(g.weights)...))
 weights(g::SimpleWeightedDiGraph) = g.weights'
 
-inneighbors(g::SimpleWeightedDiGraph, v::Integer) = g.weights[v,:].nzind
+inneighbors(g::SimpleWeightedDiGraph, v::Integer) = Iterators.filter(!iszero, g.weights[v,:].nzind)
+indegree(g::SimpleWeightedDiGraph, v::Integer) = length(inneighbors(g, v).itr)
 
 # add_edge! will overwrite weights.
 function add_edge!(g::SimpleWeightedDiGraph, e::SimpleWeightedGraphEdge)

src/simpleweightedgraph.jl

@@ -18,7 +18,7 @@ mutable struct SimpleWeightedGraph{T<:Integer, U<:Real} <: AbstractSimpleWeighte
 
 end
 
-ne(g::SimpleWeightedGraph) = nnz(g.weights) ÷ 2
+ne(g::SimpleWeightedGraph) = count(!iszero, nonzeros(g.weights)) ÷ 2
 
 SimpleWeightedGraph{T}(adjmx::SparseMatrixCSC{U, T}) where {T <: Integer, U <: Real} =
     SimpleWeightedGraph{T, U}(adjmx)
@@ -101,8 +101,8 @@ LightGraphs.SimpleGraph(g::SimpleWeightedGraph) = SimpleGraph(g.weights)
 
 edgetype(::SimpleWeightedGraph{T, U}) where {T<:Integer, U<:Real} = SimpleWeightedGraphEdge{T,U}
 
-edges(g::SimpleWeightedGraph) = (SimpleWeightedEdge(x[1], x[2], x[3]) for x in zip(findnz(triu(g.weights))...))
-weights(g::SimpleWeightedGraph) = g.weights
+edges(g::SimpleWeightedGraph) = Iterators.filter(!iszero ∘ weight, SimpleWeightedEdge(x[1], x[2], x[3]) for x in zip(findnz(triu(g.weights))...))
+weights(g::AbstractSimpleWeightedGraph) = g.weights
 inneighbors(g::SimpleWeightedGraph, x...) = outneighbors(g, x...)
 
 # add_edge! will overwrite weights.

test/simpleweightedgraph.jl

@@ -64,7 +64,7 @@ using SimpleWeightedGraphs
         gc = copy(g)
         @test add_edge!(gc, 4, 1) && gc == SimpleWeightedGraph(cycle_graph(4))
 
-        @test @inferred(inneighbors(g, 2)) == @inferred(outneighbors(g, 2)) == @inferred(neighbors(g,2)) == [1,3]
+        @test @inferred(collect(inneighbors(g, 2))) == @inferred(collect(outneighbors(g, 2))) == @inferred(collect(neighbors(g,2))) == [1,3]
         @test @inferred(add_vertex!(gc))   # out of order, but we want it for issubset
         @test @inferred(g ⊆ gc)
         @test @inferred(has_vertex(gc, 5))
@@ -115,8 +115,8 @@ using SimpleWeightedGraphs
         @test SimpleWeightedEdge(2,3) in edges(g)
         @test !(SimpleWeightedEdge(3,2) in edges(g))
         @test @inferred(nv(g)) == 4
-        @test outneighbors(g, 2) == [3]
-        @test inneighbors(g, 2) == [1]
+        @test collect(outneighbors(g, 2)) == [3]
+        @test collect(inneighbors(g, 2)) == [1]
 
         @test @inferred(has_edge(g, 2, 3))
         @test @inferred(!has_edge(g, 3, 2))
@@ -130,8 +130,8 @@ using SimpleWeightedGraphs
         gc = @inferred(copy(g))
         @test @inferred(add_edge!(gc, 4, 1)) && gc == SimpleWeightedDiGraph(cycle_digraph(4))
 
-        @test @inferred(inneighbors(g, 2)) == [1]
-        @test @inferred(outneighbors(g, 2)) == @inferred(neighbors(g,2)) == [3]
+        @test @inferred(collect(inneighbors(g, 2))) == [1]
+        @test @inferred(collect(outneighbors(g, 2))) == @inferred(collect(neighbors(g,2))) == [3]
         @test @inferred(add_vertex!(gc))   # out of order, but we want it for issubset
         @test @inferred(g ⊆ gc)
         @test @inferred(has_vertex(gc, 5))
@@ -182,7 +182,7 @@ using SimpleWeightedGraphs
     @test @inferred(get_weight(g, 1, 2)) == 3
 
     g = SimpleWeightedDiGraph(path_graph(5), 4.0)
-    @test sum(weights(g)) == ne(g) * 4.0
+    @test sum(collect(weights(g)))== ne(g) * 4.0
 
     gx = Graph(4,3)
     for g in testsimplegraphs(gx)
@@ -222,6 +222,16 @@ using SimpleWeightedGraphs
     @test SimpleDiGraph(SimpleWeightedDiGraph(cycle_graph(4))) == SimpleDiGraph(cycle_graph(4))
     @test SimpleGraph(SimpleWeightedGraph(path_graph(5))) == path_graph(5)
 
+
+    # test structural zeros.
+    g = SimpleWeightedDiGraph(path_digraph(5))
+    add_edge!(g, 2, 3, 5)
+    @test has_edge(g, 2, 3)
+    rem_edge!(g, 2, 3)
+    @test !has_edge(g, 2, 3)
+    @test SimpleWeightedEdge(2, 3) ∉ edges(g)
+    @test weights(g)[2, 3] == 0
+
     @test SimpleWeightedGraph(cycle_graph(4)) == SimpleWeightedGraph(SimpleWeightedGraph(cycle_graph(4)))
     @test SimpleWeightedDiGraph(cycle_digraph(4)) == SimpleWeightedDiGraph(SimpleWeightedDiGraph(cycle_digraph(4)))
 
@@ -319,4 +329,17 @@ using SimpleWeightedGraphs
         @test g[1, 3, Val{:weight}()] ≈ 0
         @test g[2, 3, Val{:weight}()] ≈ 0.5
     end
+
+    # test digraph construction
+    g = LightGraphs.path_digraph(4)
+    h = SimpleWeightedDiGraph(g)
+    @test collect(edges(g)) == collect(edges(h))
+
+    # test degrees
+    @test outdegree(h) == [1, 1, 1, 0]
+    for v in 1:nv(h)
+        @test outdegree(h, v) == outdegree(h)[v]
+        @test indegree(h, v) == indegree(h)[v]
+        @test degree(h, v) == outdegree(h, v) + indegree(h, v)
+    end
 end