BayesNet does not support unicode characters

[zouhairm]

d = BayesNet([:a, :ux, :wx, :xk, :xkp])

works ok, but

d = BayesNet([:α, :ux, :wx, :xk, :xkp])

produces an error:

invalid ASCII sequence
 in setindex! at array.jl:307
 in writemime at /home/zouhair/.julia/v0.3/BayesNets/src/BayesNets.jl:102
 in sprint at iostream.jl:229
 in display_dict at /home/zouhair/.julia/v0.3/IJulia/src/execute_request.jl:31

Since Julia supports unicode, one would expect to be able to use them as graph nodes.

Seems like the issue is actually with TikzGraphs which only handles ASCIIstrings:

function plotHelper(g::GenericGraph, libraryname::String, layoutname::String, options::String, labels::AbstractArray{ASCIIString,1})

Is there a UTF8strings to "latex" symbol?

[mykelk]

I updated the code (along with TikzGraphs.jl) to output unicode to the tex file. The remaining issue is to get lualatex to display the unicode correctly. I think we need to just specify a font that supports the unicode using fontspec (maybe through an update to the preamble.tex in TikzGraphs). If you try to run your example now, you won't get an error anymore, but the unicode characters will be blank.

[mykelk]

You also need the latest commit to TikzGraphs.jl.