[Haskell-beginners] reorganizing lists

[Martin Drautzburg]

On Monday, 28. January 2013 19:37:53 Bryce Verdier wrote:
> Hi All,
> 
> At the moment I have a list of lists. The inner list is a coordinate,
> like (x,y) but is [x,y] instead. What I would like to do is group all
> the x's into one list, and the y's into another. I know I can do this
> with calling 2 maps on the container, but I would also like to do this
> in one iteration.

Something like this?
	groupMe  = foldl (\[rx,ry] [x,y] -> [x:rx,y:ry]) [[],[]] 


*Main> groupMe [[1,2],[1,3],[2,3]]
[[2,1,1],[3,3,2]]
-- 
Martin