Metadata lost when a vertex is removed. about metagraphs.jl HOT 4 CLOSED

julia> g = MetaGraph(Graph(5))
{5, 0} undirected Int64 metagraph with Float64 weights defined by :weight (default weight 1.0)

julia> for v in vertices(g)
             set_prop!(g, v, :name, string(v))
           end

julia> get_prop(g,1,:name)
"1"

julia> rem_vertex!(g,1)
true

julia> get_prop(g,5,:name)
"5"

julia> get_prop(g,4,:name)
"4"

julia> get_prop(g,3,:name)
"3"

julia> get_prop(g,2,:name)
"2"

julia> get_prop(g,1,:name)
ERROR: KeyError: key :name not found
Stacktrace:
 [1] getindex at ./dict.jl:474 [inlined]
 [2] get_prop(::MetaGraphs.MetaGraph{Int64,Float64}, ::Int64, ::Symbol) at /Users/bromberger1/.julia/v0.6/MetaGraphs/src/MetaGraphs.jl:138

julia> g
{4, 0} undirected Int64 metagraph with Float64 weights defined by :weight (default weight 1.0)

    mga = MetaGraph(Graph(5))
    for v in vertices(mga)
        set_prop!(mga, v, :name, string(v))
    end
    @test get_prop(mga, 1, :name) == "1"
    @test get_prop(mga, 5, :name) == "5"
    @test rem_vertex!(mga, 1)
    @test get_prop(mga, 1, :name) == "5"
    @test isempty(props(mga, 5))

  let g = MetaGraph(Graph(5))
    for v in vertices(g)
      set_prop!(g, v, :name, string(v))
    end
    for v in vertices(g)
      println("vertex ", v, " under scrutiny")
      if get_prop(g, v, :name) == "1"
        rem_vertex!(g, v)
        println("vertex ", v, " removed")
      end
    end
    map(v -> (v, get_prop(g, v, :name)), filter_vertices(g, :name))
  end
  
  vertex 1 under scrutiny
  vertex 1 removed
  vertex 2 under scrutiny
  vertex 3 under scrutiny
  vertex 4 under scrutiny
  vertex 5 under scrutiny
  ERROR: KeyError: key :name not found
  Stacktrace:
   [1] getindex at ./dict.jl:474 [inlined]
   [2] get_prop(::MetaGraphs.MetaGraph{Int64,Float64}, ::Int64, ::Symbol) at /home/yves/.julia/v0.6/MetaGraphs/src/MetaGraphs.jl:142
   [3] anonymous at ./<missing>:7

  let g = Graph(5), labels = Dict()
    for v in vertices(g)
      labels[v] = string(v)
    end
    for v in vertices(g)
      println("vertex ", v, " under scrutiny")
      if labels[v] == "1"
        rem_vertex!(g, v)
        labels[v] = labels[end]
        println("vertex ", v, " removed")
      end
    end
    map(v -> (v, labels[v]) , vertices(g))
  end
  
  vertex 1 under scrutiny
  vertex 1 removed
  vertex 2 under scrutiny
  vertex 3 under scrutiny
  vertex 4 under scrutiny
  vertex 5 under scrutiny
  4-element Array{Tuple{Int64,String},1}:
   (1, "5")
   (2, "2")
   (3, "3")
   (4, "4")

julia> mga = MetaGraph(Graph(5))
{5, 0} undirected Int64 metagraph with Float64 weights defined by :weight (default weight 1.0)

julia> for v in vertices(mga)
               set_prop!(mga, v, :name, string(v))
           end

julia> z = induced_subgraph(mga, [1,3,5])
({3, 0} undirected Int64 metagraph with Float64 weights defined by :weight (default weight 1.0), [1, 3, 5])

julia> g = z[1]
{3, 0} undirected Int64 metagraph with Float64 weights defined by :weight (default weight 1.0)

julia> props(g, 1)
Dict{Symbol,Any} with 1 entry:
  :name => "1"

julia> props(g, 2)
Dict{Symbol,Any} with 1 entry:
  :name => "3"

julia> props(g, 3)
Dict{Symbol,Any} with 1 entry:
  :name => "5"

julia> mga = MetaGraph(Graph(5))

{5, 0} undirected Int64 metagraph with Float64 weights defined by :weight (default weight 1.0)

julia> for v in vertices(mga)
               set_prop!(mga, v, :name, string(v))
           end

julia> rem_vertex!(mga,1)
true

julia> rem_vertex!(mga,6)
false