On Thu, Aug 12, 2010 at 10:11 PM, Patrick LeBoutillier
I need a function that, given t and the list of t*m measures, can spilt the measures by track, returning a list of t lists, each containing m measures. I cannot figure out how to do this, even though it seems to me like it shouldn't be too hard... I can't figure out how to "update" the lists of lists when I want to add a new element.
Do anyone have any ideas?
I won't post the complete code and will just throw ideas around, please let us know if you still get stuck =). We have the following function in the Prelude: splitAt :: Int -> [a] -> ([a], [a]) For example, Prelude> splitAt 3 [1..12] ([1,2,3],[4,5,6,7,8,9,10,11,12]) So you can write the following function (you can choose another name): separate :: Int -> [a] -> [[a]] For example, Prelude> separate 3 [1..12] [[1,2,3],[4,5,6],[7,8,9],[10,11,12]] But that's not what we wanted. Hmmm, from Data.List we have transpose :: [[a]] -> [[a]] For example: Prelude Data.List> transpose [[1,2,3],[4,5,6],[7,8,9],[10,11,12]] [[1,4,7,10],[2,5,8,11],[3,6,9,12]] Bingo! Hope that helps ;-), -- Felipe.