Data.Packed.Convert

1 files changed, 59 insertions, 0 deletions

diff --git a/lib/Data/Packed/Convert.hs b/lib/Data/Packed/Convert.hs
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+-----------------------------------------------------------------------------
+-- |
+-- 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))