View source for Sorting large arrays

An example of how to efficiently sort large arrays in native Haskell, using the [http://hackage.haskell.org/package/uvector uvector] array type, and the [http://hackage.haskell.org/package/uvector-algorithms uvector-algorithms] package.

This is an in-place sort, using destructive updates in the [[Monad/ST|ST]] (i.e. mutable memory) monad.

<haskell>

{-

Sort 10M floats efficiently in pure Haskell.
Uses uvector and uvector-algorithms.

-}

import Control.Monad.ST
import Data.Array.Vector
import Data.Array.Vector.Algorithms.Merge

main = do
    let e = runST (do
                v <- newMU (10^7) :: ST s (MUArr Float s)
                sort v
                readMU v 0)
    print e

</haskell>

It presents the smallest element of the array after sorting.

Compiling:

    ghc -O2 --make A.hs

Running:

    $ time ./A
    0.0
    ./A  1.22s user 0.04s system 98% cpu 1.278 total