hmatrix-mmap 0.0.1 → 0.0.2

raw patch · 2 files changed

+63/−3 lines, 2 filesPVP ok

version bump matches the API change (PVP)

API changes (from Hackage documentation)

Files

• Data/Packed/Vector/MMap.hs +62/−2
• hmatrix-mmap.cabal +1/−1

@@ -1,16 +1,61 @@ {-# LANGUAGE ScopedTypeVariables #-}++-- | Functions to represent a 'Vector' on disk in efficient, if+-- unportable, ways.+--+-- This module uses memory-mapping, a feature of all modern+-- operating-systems, to mirror the disk contents in memory. There are+-- quite a few advantages to memory-mapping files instead of reading+-- the files traditionally:+--+--  * Speed: memory-mapping is often much faster than traditional+--    reading.+--+--  * Memory efficiency: Memory-mapped files are loaded into RAM+--    on-demand, and easily swapped out. The upside is that the+--    program can work with data-sets larger than the available RAM,+--    as long as they are accessed carefully.+--+-- The caveat to using memory-mapping is that it makes the files+-- specific to the current architecture because of the endianness of+-- the data. For more information, see the description in+-- "System.IO.MMap"+--+-- If you wish to write the contents in a portable fashion, either use+-- the ASCII load and save functions in "Numeric.Container", or use+-- the binary serialization in "Data.Binary".+ module Data.Packed.Vector.MMap (-  unsafeMMapVector+  -- * Memory-mapping 'Vector' from disk+  unsafeMMapVector,++  -- * Writing 'Vector' to disk++  -- | These functions write the 'Vector' in a way suitable for+  -- reading back with 'unsafeMMapVector'.+  hPutVector,+  writeVector ) where +import System.IO import System.IO.MMap++import Foreign.ForeignPtr+import Foreign.Ptr import Foreign.Storable  import qualified Data.Packed.Development as I import qualified Data.Packed.Vector as I import Data.Int --- | Map a file into memory ('ReadOnly' mode) as an immutable vector.+---------------------------+-- Memory-Mapping 'Vector' from disk++-- | Map a file into memory (read-only) as a 'Vector'.+--+-- It is considered unsafe because changes to the underlying file may+-- (or may not) be reflected in the 'Vector', which breaks referential+-- transparency. unsafeMMapVector :: forall a. Storable a => FilePath -- ^ Path of the file to map                                          -> Maybe (Int64, Int) -- ^ 'Nothing' to map entire file into memory, otherwise 'Just (fileOffset, elementCount)'                                          -> IO (I.Vector a)@@ -20,3 +65,18 @@           Nothing -> Nothing           Just (start, length) -> Just (start, length * sizeOf (undefined :: a))      return $ I.unsafeFromForeignPtr foreignPtr offset (size `div` sizeOf (undefined :: a))++---------------------------+-- Writing 'Vector' to disk++-- | Write out a vector verbatim into an open file handle.+hPutVector :: forall a. Storable a => Handle -> I.Vector a -> IO ()+hPutVector h v = withForeignPtr fp $ \p -> hPutBuf h (p `plusPtr` offset) sz+      where+        (fp, offset, n) = I.unsafeToForeignPtr v+        eltsize = sizeOf (undefined :: a)+        sz = n * eltsize++-- | Write the vector verbatim to a file.+writeVector :: forall a. Storable a => FilePath -> I.Vector a -> IO ()+writeVector fp v = withFile fp WriteMode $ \h -> hPutVector h v

@@ -1,5 +1,5 @@ Name:           hmatrix-mmap-Version:        0.0.1+Version:        0.0.2 License:        BSD3 License-File:   LICENSE Author:         Daniel Peebles <pumpkingod@gmail.com>, Alan Falloon <alan.falloon@gmail.com>