Drawing graphs without edges not working.

[simonschoelly]

It looks as if it is not possible to plot a graph without edges:

julia> using LightGraphs, Plots, GraphRecipes

julia> plot(SimpleGraph(5))
ERROR: ArgumentError: reducing over an empty collection is not allowed
Stacktrace:
 [1] _empty_reduce_error() at ./reduce.jl:299
 [2] reduce_empty(::Function, ::Type{Int64}) at ./reduce.jl:309
 [3] mapreduce_empty(::typeof(identity), ::Function, ::Type{T} where T) at ./reduce.jl:343
 [4] reduce_empty(::Base.MappingRF{typeof(identity),typeof(max)}, ::Type{Int64}) at ./reduce.jl:329
 [5] reduce_empty_iter at ./reduce.jl:355 [inlined]
 [6] mapreduce_empty_iter(::Function, ::Function, ::Array{Int64,1}, ::Base.HasEltype) at ./reduce.jl:351
 [7] _mapreduce at ./reduce.jl:400 [inlined]
 [8] _mapreduce_dim at ./reducedim.jl:318 [inlined]
 [9] #mapreduce#620 at ./reducedim.jl:310 [inlined]
 [10] mapreduce at ./reducedim.jl:310 [inlined]
 [11] _maximum at ./reducedim.jl:727 [inlined]
 [12] _maximum at ./reducedim.jl:726 [inlined]
 [13] #maximum#631 at ./reducedim.jl:722 [inlined]
 [14] maximum at ./reducedim.jl:722 [inlined]
 [15] get_adjacency_matrix(::Array{Int64,1}, ::Array{Int64,1}, ::Array{Float64,1}) at /home/simon/.julia/dev/GraphRecipes/src/graphs.jl:108
 [16] macro expansion at /home/simon/.julia/dev/GraphRecipes/src/graphs.jl:360 [inlined]
 [17] apply_recipe(::AbstractDict{Symbol,Any}, ::GraphRecipes.GraphPlot) at /home/simon/.julia/packages/RecipesBase/92zOw/src/RecipesBase.jl:282
 [18] _process_userrecipes!(::Any, ::Any, ::Any) at /home/simon/.julia/packages/RecipesPipeline/uPBKQ/src/user_recipe.jl:36
 [19] recipe_pipeline!(::Any, ::Any, ::Any) at /home/simon/.julia/packages/RecipesPipeline/uPBKQ/src/RecipesPipeline.jl:70
 [20] _plot!(::Plots.Plot, ::Any, ::Any) at /home/simon/.julia/packages/Plots/vsE7b/src/plot.jl:172
 [21] #plot#129 at /home/simon/.julia/packages/Plots/vsE7b/src/plot.jl:58 [inlined]
 [22] plot(::Any) at /home/simon/.julia/packages/Plots/vsE7b/src/plot.jl:52
 [23] top-level scope at REPL[146]:1

[xinyuhuang97]

I met the same problem and I have no choice but add an edge (i,i) for each node which doesn't cause misunderstanding for my question, may this will help someone and may the author find a solution one day.