Update numeric-prelude and fixed-vector.

[numerical-analysis.git] / src / Linear / Vector.hs

diff --git a/src/Linear/Vector.hs b/src/Linear/Vector.hs
index aba9e5fb2d28d3d5ae43665ca95353f3cc8b6fd5..42d47a39e58670136b5300dd1f83f007ce85fc2e 100644 (file)
--- a/src/Linear/Vector.hs
+++ b/src/Linear/Vector.hs
@@ -9,69 +9,32 @@ where
 
 import Data.Vector.Fixed (
   Dim,
-  Fun(..),
   N1,
-  N2,
-  N3,
   N4,
+  N5,
+  S,
   Vector(..),
-  construct,
-  inspect,
+  fromList,
   toList,
   )
 import qualified Data.Vector.Fixed as V (
+  (!),
   length,
   )
+import Data.Vector.Fixed.Boxed
 
+type Vec1 = Vec N1
+type Vec4 = Vec N4
+type Vec5 = Vec N5
 
--- * Low-dimension vector wrappers.
---
--- These wrappers are instances of 'Vector', so they inherit all of
--- the userful instances defined above. But, they use fixed
--- constructors, so you can pattern match out the individual
--- components.
-
-data D1 a = D1 a
-type instance Dim D1 = N1
-instance Vector D1 a where
-  inspect (D1 x) (Fun f) = f x
-  construct = Fun D1
-
-data D2 a = D2 a a
-type instance Dim D2 = N2
-instance Vector D2 a where
-  inspect (D2 x y) (Fun f) = f x y
-  construct = Fun D2
-
-data D3 a = D3 a a a
-type instance Dim D3 = N3
-instance Vector D3 a where
-  inspect (D3 x y z) (Fun f) = f x y z
-  construct = Fun D3
 
-data D4 a = D4 a a a a
-type instance Dim D4 = N4
-instance Vector D4 a where
-  inspect (D4 w x y z) (Fun f) = f w x y z
-  construct = Fun D4
-
-
--- | Unsafe indexing.
---
---   Examples:
---
---   >>> let v1 = D2 1 2
---   >>> v1 ! 1
---   2
---
-(!) :: (Vector v a) => v a -> Int -> a
-(!) v1 idx = (toList v1) !! idx
 
 -- | Safe indexing.
 --
 --   Examples:
 --
---   >>> let v1 = D3 1 2 3
+--   >>> import Data.Vector.Fixed (mk3)
+--   >>> let v1 = mk3 1 2 3 :: Vec3 Int
 --   >>> v1 !? 2
 --   Just 3
 --   >>> v1 !? 3
@@ -80,4 +43,21 @@ instance Vector D4 a where
 (!?) :: (Vector v a) => v a -> Int -> Maybe a
 (!?) v1 idx
   | idx < 0 || idx >= V.length v1 = Nothing
-  | otherwise                     = Just $ v1 ! idx
+  | otherwise                     = Just $ v1 V.! idx
+
+
+-- | Remove an element of the given vector.
+--
+--   Examples:
+--
+--   >>> import Data.Vector.Fixed (mk3)
+--   >>> let b = mk3 1 2 3 :: Vec3 Int
+--   >>> delete b 1 :: Vec2 Int
+--   fromList [1,3]
+--
+delete :: (Vector v a, Vector w a, Dim v ~ S (Dim w)) => v a -> Int -> w a
+delete v1 idx =
+  fromList $ (lhalf ++ rhalf')
+  where
+    (lhalf, rhalf) = splitAt idx (toList v1)
+    rhalf' = tail rhalf