Data.Packed.Convert

2 files changed, 68 insertions, 0 deletions

diff --git a/lib/Data/Packed/Convert.hs b/lib/Data/Packed/Convert.hs
new file mode 100644
index 0000000..55fdf8f
--- /dev/null
+++ b/lib/Data/Packed/Convert.hs
@@ -0,0 +1,59 @@
+-----------------------------------------------------------------------------
+-- |
+-- Module      :  Data.Packed.Convert
+-- Copyright   :  (c) Alberto Ruiz 2008
+-- License     :  GPL-style
+--
+-- Maintainer  :  Alberto Ruiz <aruiz@um.es>
+-- Stability   :  provisional
+-- Portability :  portable
+--
+-- Conversion of Vectors and Matrices to and from the standard Haskell arrays.
+--
+-----------------------------------------------------------------------------
+
+module Data.Packed.Convert (
+    vectorToStorableArray,
+    storableArrayToVector,
+--    unsafeUpdateVector,
+) where
+
+import Data.Packed.Internal
+import Data.Array.Storable
+import Foreign
+
+-- | Creates a StorableArray indexed from 0 to dim -1.
+--   (Memory is efficiently copied, so you can then freely modify the obtained array)
+vectorToStorableArray :: Storable t => Vector t -> IO (StorableArray Int t)
+vectorToStorableArray v = do
+    r <- cloneVector v
+    unsafeForeignPtrToStorableArray (fptr r) (0,dim r -1)
+
+-- | Creates a Vector from a StorableArray.
+--   (Memory is efficiently copied, so posterior changes in the array will not affect the result)
+storableArrayToVector :: Storable t => StorableArray Int t -> IO (Vector t)
+storableArrayToVector s = do
+    (a,b) <- getBounds s
+    let n = (b-a+1)
+    r <- createVector n
+    withStorableArray s $ \p -> do
+        let f _ d =  copyArray d p n >> return 0
+        app1 f vec r "storableArrayToVector"
+    return r
+
+
+unsafeVectorToStorableArray :: Storable t => Vector t -> IO (StorableArray Int t)
+unsafeVectorToStorableArray v = unsafeForeignPtrToStorableArray (fptr v) (0,dim v -1)
+
+--unsafeStorableArrayToVector :: Storable t => StorableArray Int t -> IO (Vector t)
+--unsafeStorableArrayToVector s = undefined -- the foreign ptr of Storable Array is not available?
+
+-----------------------------------------------------------------
+
+
+unsafeUpdateVector :: Storable t => Int -- ^ position
+                           -> (t->t)    -- ^ modification function
+                           -> Vector t  -- ^ source
+                           -> IO ()     -- ^ result
+unsafeUpdateVector k h v = do
+    withForeignPtr (fptr v) $ \s -> pokeElemOff s k (h (v`at'`k))
diff --git a/lib/Data/Packed/Internal/Vector.hs b/lib/Data/Packed/Internal/Vector.hs
index 5a42f9d..772aafd 100644
--- a/lib/Data/Packed/Internal/Vector.hs
+++ b/lib/Data/Packed/Internal/Vector.hs
@@ -166,3 +166,12 @@ updateVector k h (v@V {dim=n})
                       >> return 0
         app2 f vec v vec r "updateVector"
         return r
+
+-----------------------------------------------------------------
+
+cloneVector :: Storable t => Vector t -> IO (Vector t)
+cloneVector (v@V {dim=n}) = do
+        r <- createVector n
+        let f _ s _ d =  copyArray d s n >> return 0
+        app2 f vec v vec r "cloneVector"
+        return r