11 files changed, 96 insertions, 56 deletions

diff --git a/packages/base/CHANGELOG b/packages/base/CHANGELOG
index 27c4d31..93b2594 100644
--- a/packages/base/CHANGELOG
+++ b/packages/base/CHANGELOG
@@ -7,7 +7,10 @@
     
     * remap, ccompare, sortIndex
 
-    * experimental support of type safe modular arithmetic
+    * experimental support of type safe modular arithmetic, including linear
+      systems and lu factorization
+    
+    * elementary row operations in ST monad
 
     * old compatibility modules removed
 
diff --git a/packages/base/src/Internal/Matrix.hs b/packages/base/src/Internal/Matrix.hs
index e0f5ed2..e4b1226 100644
--- a/packages/base/src/Internal/Matrix.hs
+++ b/packages/base/src/Internal/Matrix.hs
@@ -262,15 +262,7 @@ compat m1 m2 = rows m1 == rows m2 && cols m1 == cols m2
 
 ------------------------------------------------------------------
 
-{- | Supported matrix elements.
-
-    This class provides optimized internal
-    operations for selected element types.
-    It provides unoptimised defaults for any 'Storable' type,
-    so you can create instances simply as:
-
-    >instance Element Foo
--}
+-- | Supported matrix elements.
 class (Storable a) => Element a where
     transdata :: Int -> Vector a -> Int -> Vector a
     constantD  :: a -> Int -> Vector a
diff --git a/packages/base/src/Internal/ST.hs b/packages/base/src/Internal/ST.hs
index a84ca25..434fe63 100644
--- a/packages/base/src/Internal/ST.hs
+++ b/packages/base/src/Internal/ST.hs
@@ -10,7 +10,7 @@
 -- Stability   :  provisional
 --
 -- In-place manipulation inside the ST monad.
--- See examples/inplace.hs in the distribution.
+-- See @examples/inplace.hs@ in the repository.
 --
 -----------------------------------------------------------------------------
 
@@ -21,8 +21,8 @@ module Internal.ST (
     -- * Mutable Matrices
     STMatrix, newMatrix, thawMatrix, freezeMatrix, runSTMatrix,
     readMatrix, writeMatrix, modifyMatrix, liftSTMatrix,
-    axpy, scal, swap, extractMatrix, setMatrix, rowOpST,
-    mutable,
+--  axpy, scal, swap, rowOp,
+    mutable, extractMatrix, setMatrix, rowOper, RowOper(..), RowRange(..), ColRange(..),
     -- * Unsafe functions
     newUndefinedVector,
     unsafeReadVector, unsafeWriteVector,
@@ -178,16 +178,55 @@ newMatrix v r c = unsafeThawMatrix $ reshape c $ runSTVector $ newVector v (r*c)
 
 --------------------------------------------------------------------------------
 
-rowOpST :: Element t => Int -> t -> Int -> Int -> Int -> Int -> STMatrix s t -> ST s ()
-rowOpST c x i1 i2 j1 j2 (STMatrix m) = unsafeIOToST (rowOp c x i1 i2 j1 j2 m)
+data ColRange = AllCols
+              | ColRange Int Int
+              | Col Int
+              | FromCol Int
 
-axpy (STMatrix m) a i j = rowOpST 0 a i j 0 (cols m -1) (STMatrix m)
-scal (STMatrix m) a i   = rowOpST 1 a i i 0 (cols m -1) (STMatrix m)
-swap (STMatrix m) i j   = rowOpST 2 0 i j 0 (cols m -1) (STMatrix m)
+getColRange c AllCols = (0,c-1)
+getColRange c (ColRange a b) = (a `mod` c, b `mod` c)
+getColRange c (Col a) = (a `mod` c, a `mod` c)
+getColRange c (FromCol a) = (a `mod` c, c-1)
 
-extractMatrix (STMatrix m) i1 i2 j1 j2 = unsafeIOToST (extractR m 0 (idxs[i1,i2]) 0 (idxs[j1,j2]))
+data RowRange = AllRows
+              | RowRange Int Int
+              | Row Int
+              | FromRow Int
+
+getRowRange r AllRows = (0,r-1)
+getRowRange r (RowRange a b) = (a `mod` r, b `mod` r)
+getRowRange r (Row a) = (a `mod` r, a `mod` r)
+getRowRange r (FromRow a) = (a `mod` r, r-1)
+
+data RowOper t = AXPY t Int Int  ColRange
+               | SCAL t RowRange ColRange
+               | SWAP Int Int    ColRange
+
+rowOper :: (Num t, Element t) => RowOper t -> STMatrix s t -> ST s ()
+
+rowOper (AXPY x i1 i2 r) (STMatrix m) = unsafeIOToST $ rowOp 0 x i1' i2' j1 j2 m
+  where
+    (j1,j2) = getColRange (cols m) r
+    i1' = i1 `mod` (rows m)
+    i2' = i2 `mod` (rows m)
+
+rowOper (SCAL x rr rc) (STMatrix m) = unsafeIOToST $ rowOp 1 x i1 i2 j1 j2 m
+  where
+    (i1,i2) = getRowRange (rows m) rr
+    (j1,j2) = getColRange (cols m) rc
+
+rowOper (SWAP i1 i2 r) (STMatrix m) = unsafeIOToST $ rowOp 2 0 i1' i2' j1 j2 m
+  where
+    (j1,j2) = getColRange (cols m) r
+    i1' = i1 `mod` (rows m)
+    i2' = i2 `mod` (rows m)
+
+
+extractMatrix (STMatrix m) rr rc = unsafeIOToST (extractR m 0 (idxs[i1,i2]) 0 (idxs[j1,j2]))
+  where
+    (i1,i2) = getRowRange (rows m) rr
+    (j1,j2) = getColRange (cols m) rc
 
---------------------------------------------------------------------------------
 
 mutable :: Storable t => (forall s . (Int, Int) -> STMatrix s t -> ST s u) -> Matrix t -> (Matrix t,u)
 mutable f a = runST $ do
diff --git a/packages/base/src/Internal/Static.hs b/packages/base/src/Internal/Static.hs
index 01c2205..0068313 100644
--- a/packages/base/src/Internal/Static.hs
+++ b/packages/base/src/Internal/Static.hs
@@ -34,6 +34,9 @@ import Text.Printf
 
 --------------------------------------------------------------------------------
 
+type ℝ = Double
+type ℂ = Complex Double
+
 newtype Dim (n :: Nat) t = Dim t
   deriving Show
 
diff --git a/packages/base/src/Internal/Util.hs b/packages/base/src/Internal/Util.hs
index 2650ac8..09ba21c 100644
--- a/packages/base/src/Internal/Util.hs
+++ b/packages/base/src/Internal/Util.hs
@@ -65,7 +65,7 @@ import Internal.Element
 import Internal.Container
 import Internal.Vectorized
 import Internal.IO
-import Internal.Algorithms hiding (i,Normed,swap)
+import Internal.Algorithms hiding (i,Normed,swap,linearSolve')
 import Numeric.Matrix()
 import Numeric.Vector()
 import Internal.Random
@@ -155,7 +155,7 @@ infixl 3 &
 (&) :: Vector Double -> Vector Double -> Vector Double
 a & b = vjoin [a,b]
 
-{- | horizontal concatenation of real matrices
+{- | horizontal concatenation
 
 >>> ident 3 ||| konst 7 (3,4)
 (3><7)
@@ -165,7 +165,7 @@ a & b = vjoin [a,b]
 
 -}
 infixl 3 |||
-(|||) :: Matrix Double -> Matrix Double -> Matrix Double
+(|||) :: Element t => Matrix t -> Matrix t -> Matrix t
 a ||| b = fromBlocks [[a,b]]
 
 -- | a synonym for ('|||') (unicode 0x00a6, broken bar)
@@ -174,9 +174,9 @@ infixl 3 ¦
 (¦) = (|||)
 
 
--- | vertical concatenation of real matrices
+-- | vertical concatenation
 --
-(===) :: Matrix Double -> Matrix Double -> Matrix Double
+(===) :: Element t => Matrix t -> Matrix t -> Matrix t
 infixl 2 ===
 a === b = fromBlocks [[a],[b]]
 
@@ -588,7 +588,7 @@ gaussElim_2 a b = flipudrl r
   where
     flipudrl = flipud . fliprl
     splitColsAt n = (takeColumns n &&& dropColumns n)
-    go f x y = splitColsAt (cols a) (down f $ fromBlocks [[x,y]])
+    go f x y = splitColsAt (cols a) (down f $ x ||| y)
     (a1,b1) = go (snd . swapMax 0) a b
     ( _, r) = go id (flipudrl $ a1) (flipudrl $ b1)
 
@@ -600,7 +600,7 @@ gaussElim_1
 
 gaussElim_1 x y = dropColumns (rows x) (flipud $ fromRows s2)
   where
-    rs = toRows $ fromBlocks [[x , y]]
+    rs = toRows $ x ||| y
     s1 = fromRows $ pivotDown (rows x) 0 rs      -- interesting
     s2 = pivotUp (rows x-1) (toRows $ flipud s1)
 
@@ -637,12 +637,15 @@ pivotUp n xs
 
 --------------------------------------------------------------------------------
 
-gaussElim a b = dropColumns (rows a) $ fst $ mutable gaussST (fromBlocks [[a,b]])
+gaussElim a b = dropColumns (rows a) $ fst $ mutable gaussST (a ||| b)
 
 gaussST (r,_) x = do
     let n = r-1
+        axpy m a i j = rowOper (AXPY a i j AllCols)     m
+        swap m i j   = rowOper (SWAP i j AllCols)       m
+        scal m a i   = rowOper (SCAL a (Row i) AllCols) m
     forM_ [0..n] $ \i -> do
-        c <- maxIndex . abs . flatten <$> extractMatrix x i n i i
+        c <- maxIndex . abs . flatten <$> extractMatrix x (FromRow i) (Col i)
         swap x i (i+c)
         a <- readMatrix x i i
         when (a == 0) $ error "singular!"
@@ -656,22 +659,23 @@ gaussST (r,_) x = do
             axpy x (-b) i j
 
 
-luST ok (r,c) x = do
-    let n = r-1
-        axpy' m a i j = rowOpST 0 a i j (i+1) (c-1) m
-    p <- thawMatrix . asColumn . range $ r
-    forM_ [0..n] $ \i -> do
-        k <- maxIndex . abs . flatten <$> extractMatrix x i n i i
-        writeMatrix p i 0 (fi (k+i))
+
+luST ok (r,_) x = do
+    let axpy m a i j = rowOper (AXPY a i j (FromCol (i+1))) m
+        swap m i j   = rowOper (SWAP i j AllCols)           m
+    p <- newUndefinedVector r
+    forM_ [0..r-1] $ \i -> do
+        k <- maxIndex . abs . flatten <$> extractMatrix x (FromRow i) (Col i)
+        writeVector p i (k+i)
         swap x i (i+k)
         a <- readMatrix x i i
         when (ok a) $ do
-            forM_ [i+1..n] $ \j -> do
+            forM_ [i+1..r-1] $ \j -> do
                 b <- (/a) <$> readMatrix x j i
-                axpy' x (-b) i j
+                axpy x (-b) i j
                 writeMatrix x j i b
-    v <- unsafeFreezeMatrix p
-    return (map ti $ toList $ flatten v)
+    v <- unsafeFreezeVector p
+    return (toList v)
 
 
 --------------------------------------------------------------------------------
diff --git a/packages/base/src/Numeric/LinearAlgebra.hs b/packages/base/src/Numeric/LinearAlgebra.hs
index 0f8efa4..fe524cc 100644
--- a/packages/base/src/Numeric/LinearAlgebra.hs
+++ b/packages/base/src/Numeric/LinearAlgebra.hs
@@ -80,6 +80,7 @@ module Numeric.LinearAlgebra (
     cholSolve,
     cgSolve,
     cgSolve',
+    linearSolve',
 
     -- * Inverse and pseudoinverse
     inv, pinv, pinvTol,
@@ -136,8 +137,9 @@ module Numeric.LinearAlgebra (
     Seed, RandDist(..), randomVector, rand, randn, gaussianSample, uniformSample,
 
     -- * Misc
-    meanCov, rowOuters, pairwiseD2, unitary, peps, relativeError, haussholder, optimiseMult, udot, nullspaceSVD, orthSVD, ranksv, gaussElim, luST, magnit,
-    ℝ,ℂ,iC,
+    meanCov, rowOuters, pairwiseD2, unitary, peps, relativeError, magnit,
+    haussholder, optimiseMult, udot, nullspaceSVD, orthSVD, ranksv,
+    iC,
     -- * Auxiliary classes
     Element, Container, Product, Numeric, LSDiv,
     Complexable, RealElement,
@@ -156,7 +158,7 @@ import Numeric.Vector()
 import Internal.Matrix
 import Internal.Container hiding ((<>))
 import Internal.Numeric hiding (mul)
-import Internal.Algorithms hiding (linearSolve,Normed,orth,luPacked')
+import Internal.Algorithms hiding (linearSolve,Normed,orth,luPacked',linearSolve')
 import qualified Internal.Algorithms as A
 import Internal.Util
 import Internal.Random
@@ -240,3 +242,5 @@ orth m = orthSVD (Left (1*eps)) m (leftSV m)
 
 luPacked' x = mutable (luST (magnit 0)) x
 
+linearSolve' x y = gaussElim x y
+
diff --git a/packages/base/src/Numeric/LinearAlgebra/Data.hs b/packages/base/src/Numeric/LinearAlgebra/Data.hs
index 1c9bb68..fffc2bd 100644
--- a/packages/base/src/Numeric/LinearAlgebra/Data.hs
+++ b/packages/base/src/Numeric/LinearAlgebra/Data.hs
@@ -53,8 +53,7 @@ module Numeric.LinearAlgebra.Data(
 
     -- * Matrix extraction
     Extractor(..), (??),
-    takeRows, takeLastRows, dropRows, dropLastRows,
-    takeColumns, takeLastColumns, dropColumns, dropLastColumns,
+    takeRows, dropRows, takeColumns, dropColumns,
     subMatrix, (?), (¿), fliprl, flipud, remap,
 
     -- * Block matrix
diff --git a/packages/base/src/Numeric/LinearAlgebra/Devel.hs b/packages/base/src/Numeric/LinearAlgebra/Devel.hs
index f572656..36c5f03 100644
--- a/packages/base/src/Numeric/LinearAlgebra/Devel.hs
+++ b/packages/base/src/Numeric/LinearAlgebra/Devel.hs
@@ -20,8 +20,7 @@ module Numeric.LinearAlgebra.Devel(
     module Internal.Foreign,
 
     -- * FFI tools
-    -- | Illustrative usage examples can be found
-    --   in the @examples\/devel@ folder included in the package.
+    -- | See @examples/devel@ in the repository.
     
     createVector, createMatrix,
     vec, mat, omat,
@@ -36,7 +35,7 @@ module Numeric.LinearAlgebra.Devel(
 
     -- * ST
     -- | In-place manipulation inside the ST monad.
-    -- See examples\/inplace.hs in the distribution.
+    -- See @examples/inplace.hs@ in the repository.
     
     -- ** Mutable Vectors
     STVector, newVector, thawVector, freezeVector, runSTVector,
@@ -44,7 +43,7 @@ module Numeric.LinearAlgebra.Devel(
     -- ** Mutable Matrices
     STMatrix, newMatrix, thawMatrix, freezeMatrix, runSTMatrix,
     readMatrix, writeMatrix, modifyMatrix, liftSTMatrix,
-    axpy,scal,swap, extractMatrix, setMatrix, mutable, rowOpST,
+    mutable, extractMatrix, setMatrix, rowOper, RowOper(..), RowRange(..), ColRange(..),
     -- ** Unsafe functions
     newUndefinedVector,
     unsafeReadVector, unsafeWriteVector,
diff --git a/packages/base/src/Numeric/LinearAlgebra/HMatrix.hs b/packages/base/src/Numeric/LinearAlgebra/HMatrix.hs
index 327f284..11c2487 100644
--- a/packages/base/src/Numeric/LinearAlgebra/HMatrix.hs
+++ b/packages/base/src/Numeric/LinearAlgebra/HMatrix.hs
@@ -13,10 +13,10 @@ compatibility with previous version, to be removed
 
 module Numeric.LinearAlgebra.HMatrix (
     module Numeric.LinearAlgebra,
-     (¦),(——)
+    (¦),(——),ℝ,ℂ,
 ) where
 
 import Numeric.LinearAlgebra
 import Internal.Util
 
-   
+
diff --git a/packages/base/src/Numeric/LinearAlgebra/Static.hs b/packages/base/src/Numeric/LinearAlgebra/Static.hs
index dee5b2c..a657bd0 100644
--- a/packages/base/src/Numeric/LinearAlgebra/Static.hs
+++ b/packages/base/src/Numeric/LinearAlgebra/Static.hs
@@ -28,7 +28,7 @@ This module is under active development and the interface is subject to changes.
 
 module Numeric.LinearAlgebra.Static(
     -- * Vector
-    ℝ, R,
+       ℝ, R,
     vec2, vec3, vec4, (&), (#), split, headTail,
     vector,
     linspace, range, dim,
@@ -71,10 +71,6 @@ import Data.Proxy(Proxy)
 import Internal.Static
 import Control.Arrow((***))
 
-
-
-
-
 ud1 :: R n -> Vector ℝ
 ud1 (R (Dim v)) = v
 
diff --git a/packages/tests/src/Numeric/LinearAlgebra/Tests.hs b/packages/tests/src/Numeric/LinearAlgebra/Tests.hs
index ffa45e7..148bbb9 100644
--- a/packages/tests/src/Numeric/LinearAlgebra/Tests.hs
+++ b/packages/tests/src/Numeric/LinearAlgebra/Tests.hs
@@ -772,6 +772,7 @@ luBenchN f n x msg = do
     time (msg ++ " "++ show n) (f m)
 
 luBench = do
+    putStrLn ""
     luBenchN luPacked  1000 (5::R)          "luPacked  Double    "
     luBenchN luPacked' 1000 (5::R)          "luPacked' Double    "
     luBenchN luPacked' 1000 (5::Mod 9973 I) "luPacked' I mod 9973"