[Haskell-cafe] Re: Graph library, was: Haskell.org GSoC

2009-02-12 Thread Achim Schneider
Daniel Kraft d...@domob.eu wrote: Don Stewart wrote: - Graphs. True graphs (the data structure) are still a weak point! There's no canonical graph library for Haskell. That sounds interesting... What do you mean by no canonical library? Are there already ones but just no standard

[Haskell-cafe] Re: Graph library, was: Haskell.org GSoC

2009-02-12 Thread Benedikt Huber
Daniel Kraft schrieb: Don Stewart wrote: - Graphs. True graphs (the data structure) are still a weak point! There's no canonical graph library for Haskell. That sounds interesting... What do you mean by no canonical library? Are there already ones but just no standard one? But in this

Re: [Haskell-cafe] Re: Graph library, was: Haskell.org GSoC

2009-02-12 Thread Ketil Malde
Benedikt Huber benj...@gmx.net writes: I would also like to see a project working on a new graph library. [...] I think a good general purpose graph library is tricky though: And please, let us have a library that is scalable! This means there should be one (or several) benchmark

Re: [Haskell-cafe] Re: Graph library, was: Haskell.org GSoC

2009-02-12 Thread Tracy Wadleigh
Benedikt writes: I think a good general purpose graph library is tricky though: - There are lot of variants of graphs (trees, bipartite, acyclic, undirected, simple, edge labeled etc.), hard to find adequate and easy to use abstraction. - There is no single 'best' implementation (mutable vs.

[Haskell-cafe] Re: Graph library, was: Haskell.org GSoC

2009-02-12 Thread Daniel Kraft
Benedikt Huber wrote: I would also like to see a project working on a new graph library. Currently, there is at least Data.Graph (just one Module, package containers), based on Array - adjacency lists, and the functional graph library (package fgl). I don't know those, but functional graph

[Haskell-cafe] Re: Graph library, was: Haskell.org GSoC

2009-02-12 Thread Benedikt Huber
Daniel Kraft schrieb: Benedikt Huber wrote: I would also like to see a project working on a new graph library. Currently, there is at least Data.Graph (just one Module, package containers), based on Array - adjacency lists, and the functional graph library (package fgl). I don't know those,

[Haskell-cafe] Re: Graph library, was: Haskell.org GSoC

2009-02-12 Thread Louis Wasserman
fgl uses pretty much the most beautiful way of abstracting graphs I've seen; a brief review: type Context a b -- a collected representation of a vertex's number, label, and all information on edges going into and out of that vertex match :: Graph gr = Node - gr a b - (Maybe (Context a b), gr a