fasteradjmx.jl

function DiGraph{T<:Real}(adjmx::AbstractMatrix{T})
    isequal(size(adjmx)...) || error("Adjacency / distance matrices must be square")

    g = DiGraph(size(adjmx,1))

    for (s,d) in zip(findn(adjmx)...)
        add_edge!(g,s,d)
    end
    return g
end

julia> zip([1,2,3],['a','b','c'])
Base.Zip2{Array{Int64,1},Array{Char,1}}([1,2,3],['a','b','c'])

julia> [x for x in ans]
3-element Array{Any,1}:
 (1,'a')
 (2,'b')
 (3,'c')

function DiGraph2{T<:Real}(adjmx::AbstractMatrix{T})
    dima,dimb = size(adjmx)
    isequal(dima,dimb) || error("Adjacency / distance matrices must be square")

    g = DiGraph(dima)
    s,d = findn(adjmx)
    @inbounds for i = 1:dima
        add_edge!(g,s[i],d[i])
    end
    return g
end