How to create a SimpleEdge{T <: Integer} edge list

[PaoloZacchia]

Hello!

Thank you for creating this package. I am a Julia user and I was looking for something like this for one of my projects.

Here's my question. I am trying to create a large directed graph starting from and edge list using function SimpleDiGraphFromIterator(). The input I provide is an iterator based on a two-column data frame, think eachrow(edgelist) where edgelist is the data frame in question.

However, I keep getting the error:

Edges must be of type SimpleEdge{T <: Integer}

so I wondered how to structure the edge list in the proper (expected) type. I went through the entire documentation and my sense is that I can only get it starting from an already constructed graph, which would defeat the purpose of using the function SimpleDiGraphFromIterator() in the first place. But maybe I haven't looked carefully enough... any help?

[Krastanov]

maybe one of these would work for you

julia> SimpleDiGraphFromIterator((Edge(a,b) for (a,b) in [(1,2),(2,3)]))

julia> SimpleDiGraphFromIterator(Edge.([(1,2),(2,3)]))

julia> SimpleDiGraphFromIterator(map(Edge, [(1,2),(2,3)]))

Only the first one is an actual iterators (broadcasting and map both eagerly construct an array).

Although there is also a build-in lazy map

julia> SimpleDiGraphFromIterator(Iterators.map(Edge, [(1,2),(2,3)]))

[Krastanov]

or to be more explicit

julia> df = DataFrame(s=[1,2],d=[2,3]);

julia> SimpleDiGraphFromIterator((Edge(r...) for r in eachrow(df)))

julia> SimpleDiGraphFromIterator(Iterators.map(splat(Edge), eachrow(df))) # if you want to not write comprehensions 

[PaoloZacchia]

Thank you! This works wonderfully! I was missing function Edge for some reason... thanks again!