Matrix transposition usind foldl

transpose.hs

import Control.Monad

transpose  [] = []
transpose  (z:zs) = foldl beta  (alpha z) zs
  where alpha = map (\x-> [x])
        beta  = zipWith (\x y-> x++[y])

transpose' [] = []
transpose' (z:zs) = map reverse $ foldl beta (alpha z) zs
  where alpha = map (\x-> [x])
        beta  = zipWith (\x y-> y:x)

amatrix = [[11,12,13,14],[21,22,23,24],[31,32,33,34]]

main =  do
  print "original:"; 
  mapM_ print amatrix
  print "transpose:"
  mapM_ print $ transpose  amatrix
  print "transpose':"
  mapM_ print $ transpose'  amatrix
  
{-

"original:"
[11,12,13,14]
[21,22,23,24]
[31,32,33,34]
"transpose:"
[11,21,31]
[12,22,32]
[13,23,33]
[14,24,34]
"transpose':"
[11,21,31]
[12,22,32]
[13,23,33]
[14,24,34]

-}