9 files changed, 101 insertions, 84 deletions

diff --git a/Setup.lhs b/Setup.lhs
index 9b055c9..3bce97b 100644
--- a/Setup.lhs
+++ b/Setup.lhs
@@ -1,7 +1,7 @@
 #! /usr/bin/env runhaskell
 
 > import Distribution.Simple
-> import System(system)
+> import System.Process(system)
 
 > main = defaultMainWithHooks autoconfUserHooks {runTests = t}
 
diff --git a/configure.hs b/configure.hs
index 9b8a177..3b12e0f 100644
--- a/configure.hs
+++ b/configure.hs
@@ -17,7 +17,9 @@
 
 -}
 
-import System
+import System.Process
+import System.Exit
+import System.Environment
 import System.Directory(createDirectoryIfMissing)
 import Data.List(isPrefixOf, intercalate)
 import Distribution.Simple.LocalBuildInfo
diff --git a/examples/parallel.hs b/examples/parallel.hs
index c82114f..566b729 100644
--- a/examples/parallel.hs
+++ b/examples/parallel.hs
@@ -1,6 +1,6 @@
 -- $ runhaskell parallel.hs 2000
 
-import System(getArgs)
+import System.Environment(getArgs)
 import Numeric.LinearAlgebra
 import Control.Parallel.Strategies
 import System.Time
diff --git a/examples/pca1.hs b/examples/pca1.hs
index 58b5577..a11eba9 100644
--- a/examples/pca1.hs
+++ b/examples/pca1.hs
@@ -2,7 +2,7 @@
 
 import Numeric.LinearAlgebra
 import System.Directory(doesFileExist)
-import System(system)
+import System.Process(system)
 import Control.Monad(when)
 
 type Vec = Vector Double
diff --git a/examples/pca2.hs b/examples/pca2.hs
index c38857c..e7ea95f 100644
--- a/examples/pca2.hs
+++ b/examples/pca2.hs
@@ -3,7 +3,7 @@
 import Numeric.LinearAlgebra
 import Graphics.Plot
 import System.Directory(doesFileExist)
-import System(system)
+import System.Process(system)
 import Control.Monad(when)
 
 type Vec = Vector Double
diff --git a/examples/vector-map.hs b/examples/vector-map.hs
deleted file mode 100644
index 7796cc0..0000000
--- a/examples/vector-map.hs
+++ /dev/null
@@ -1,74 +0,0 @@
--- use of vectorMapM
---
-
--------------------------------------------
-
-import Data.Packed.Vector
-import Numeric.LinearAlgebra.Interface
-
-import Control.Monad.State
-
--------------------------------------------
-
--- an instance of MonadIO, a monad transformer
-type VectorMonadT = StateT Int IO
-
-v :: Vector Int
-v = fromList $ take 10 [0..]
-
-test1 :: Vector Int -> IO (Vector Int)
-test1 = do
-        mapVectorM (\x -> do
-                          putStr $ (show x) ++ " "
-                          return (x + 1))
-                            
--- we can have an arbitrary monad AND do IO
-addInitialM :: Vector Int -> VectorMonadT ()
-addInitialM = mapVectorM_ (\x -> do
-                                 i <- get
-                                 liftIO $ putStr $ (show $ x + i) ++ " "
-                                 put $ x + i
-                          )
-
--- sum the values of the even indiced elements
-sumEvens :: Vector Int -> Int
-sumEvens = foldVectorWithIndex (\x a b -> if x `mod` 2 == 0 then a + b else b) 0 
-
--- sum and print running total of evens
-sumEvensAndPrint :: Vector Int -> VectorMonadT ()
-sumEvensAndPrint = mapVectorWithIndexM_ (\ i x -> do
-                                                  when (i `mod` 2 == 0) (do
-                                                                         v <- get
-                                                                         put $ v + x
-                                                                         v' <- get
-                                                                         liftIO $ putStr $ (show v') ++ " " 
-                                                                         return ())
-                                                  return ()
-                                        )
-
-indexPlusSum :: Vector Int -> VectorMonadT ()
-indexPlusSum v' = do
-                  v <- mapVectorWithIndexM (\i x -> do
-                                                    s <- get
-                                                    let inc = x+s
-                                                    liftIO $ putStr $ show (i,inc) ++ " "
-                                                    put inc
-                                                    return inc) v'
-                  liftIO $ do
-                           putStrLn ""
-                           putStrLn $ show v
-
--------------------------------------------
-
-main = do
-       v' <- test1 v
-       putStrLn ""
-       putStrLn $ show v'
-       evalStateT (addInitialM v) 0
-       putStrLn ""
-       putStrLn $ show (sumEvens v)
-       evalStateT (sumEvensAndPrint v) 0
-       putStrLn ""
-       evalStateT (indexPlusSum v) 0
-       return ()
-
diff --git a/examples/vector.hs b/examples/vector.hs
index eda9290..f531cbd 100644
--- a/examples/vector.hs
+++ b/examples/vector.hs
@@ -14,7 +14,7 @@ fromVector :: Storable t => V.Vector t -> H.Vector t
 fromVector v = unsafeFromForeignPtr p i n where
     (p,i,n) = V.unsafeToForeignPtr v
 
-toVector :: H.Vector t -> V.Vector t
+toVector :: Storable t => H.Vector t -> V.Vector t
 toVector v = V.unsafeFromForeignPtr p i n where
     (p,i,n) = unsafeToForeignPtr v
 
@@ -22,11 +22,10 @@ toVector v = V.unsafeFromForeignPtr p i n where
 
 v = V.slice 5 10 (V.fromList [1 .. 10::Double] V.++ V.replicate 10 7)
 
-w = subVector 2 3 (linspace 10 (0,2))
+w = subVector 2 3 (linspace 5 (0,1)) :: Vector Double
 
 main = do
     print v
     print $ fromVector v
     print w
     print $ toVector w
-
diff --git a/lib/Numeric/LinearAlgebra/Tests.hs b/lib/Numeric/LinearAlgebra/Tests.hs
index a44c273..630ba91 100644
--- a/lib/Numeric/LinearAlgebra/Tests.hs
+++ b/lib/Numeric/LinearAlgebra/Tests.hs
@@ -300,8 +300,8 @@ conjuTest m = mapVector conjugate (flatten (trans m)) == flatten (ctrans m)
 
 ---------------------------------------------------------------------
 
-succTest = utest "successive" $ successive_ (<) (fromList [1 :: Double,2,3,4]) == True 
-                                && successive_ (<) (fromList [1 :: Double,3,2,4]) == False
+succTest = utest "successive" $ successive_ (>) (fromList [1 :: Double,2,3,4]) == True
+                             && successive_ (<) (fromList [1 :: Double,3,2,4]) == False
 
 ---------------------------------------------------------------------
 
diff --git a/monadic.hs b/monadic.hs
new file mode 100644
index 0000000..b933de9
--- /dev/null
+++ b/monadic.hs
@@ -0,0 +1,90 @@
+-- monadic computations
+-- (contributed by Vivian McPhail)
+
+import Numeric.Container
+import Control.Monad.State
+import Control.Monad.Maybe
+
+-------------------------------------------
+
+-- an instance of MonadIO, a monad transformer
+type VectorMonadT = StateT Int IO
+
+v :: Vector Int
+v = 10 |> [0..]
+
+test1 :: Vector Int -> IO (Vector Int)
+test1 = mapVectorM $ \x -> do
+    putStr $ (show x) ++ " "
+    return (x + 1)
+
+-- we can have an arbitrary monad AND do IO
+addInitialM :: Vector Int -> VectorMonadT ()
+addInitialM = mapVectorM_ $ \x -> do
+    i <- get
+    liftIO $ putStr $ (show $ x + i) ++ " "
+    put $ x + i
+
+-- sum the values of the even indiced elements
+sumEvens :: Vector Int -> Int
+sumEvens = foldVectorWithIndex (\x a b -> if x `mod` 2 == 0 then a + b else b) 0
+
+-- sum and print running total of evens
+sumEvensAndPrint :: Vector Int -> VectorMonadT ()
+sumEvensAndPrint = mapVectorWithIndexM_ $ \ i x -> do
+    when (i `mod` 2 == 0) $ do
+        v <- get
+        put $ v + x
+        v' <- get
+        liftIO $ putStr $ (show v') ++ " "
+
+
+indexPlusSum :: Vector Int -> VectorMonadT ()
+indexPlusSum v' = do
+    let f i x = do
+            s <- get
+            let inc = x+s
+            liftIO $ putStr $ show (i,inc) ++ " "
+            put inc
+            return inc
+    v <- mapVectorWithIndexM f v'
+    liftIO $ do
+        putStrLn ""
+        putStrLn $ show v
+
+-------------------------------------------
+
+-- short circuit
+monoStep :: Double -> MaybeT (State Double) ()
+monoStep d = do
+    dp <- get
+    when (d < dp) (fail "negative difference")
+    put d
+{-# INLINE monoStep #-}
+
+isMonotoneIncreasing :: Vector Double -> Bool
+isMonotoneIncreasing v =
+    let res = evalState (runMaybeT $ (mapVectorM_ monoStep v)) (v @> 0)
+     in case res of
+        Nothing -> False
+        Just _  -> True
+
+w = fromList ([1..10]++[10,9..1]) :: Vector Double
+
+-------------------------------------------
+
+main = do
+    v' <- test1 v
+    putStrLn ""
+    putStrLn $ show v'
+    evalStateT (addInitialM v) 0
+    putStrLn ""
+    putStrLn $ show (sumEvens v)
+    evalStateT (sumEvensAndPrint v) 0
+    putStrLn ""
+    evalStateT (indexPlusSum v) 0
+    putStrLn "-----------------------"
+    print $ isMonotoneIncreasing w
+    print $ isMonotoneIncreasing (subVector 0 7 w)
+    print $ successive_ (>) v
+    print $ successive_ (>) w