So I have a text full of x and y coordinates in the for x_y new line delimited. Here is the first 3 lines:
68_1
153_16099247764943158
153_775041589

I'm massaging the data to run a liner regression on it. At the moment the program I'm writing looks like this (still a work in progress...):

module Main where

import qualified Data.Text as T
import qualified Data.Text.IO as TI
import Numeric.GSL.Fitting.Linear
import Data.Packed.Vector

buildList :: IO [[T.Text]]
buildList = TI.readFile "lin_reg_data.txt" >>= return . map (T.split (=='_')) . T.lines

--main :: IO ()
--main = do
--    values <- buildList
--    let heads = fromList $ map (\x -> read (T.unpack . head $ x):: Double) values
--    let lasts = fromList $ map (\x -> read (T.unpack . last $ x):: Double) values
--    print linear heads lasts


I'm just trying to find a way to not iterate over "vaues" twice as that seems like a waste of computing time to me. Of course any advice on this would be appreciated.

Bryce


On 01/28/2013 10:42 AM, Ozgur Akgun wrote: