X-Git-Url: http://gitweb.michael.orlitzky.com/?a=blobdiff_plain;f=src%2FFunctionValues.hs;h=0d84801f3f082532d232e75d40f626018f37f0de;hb=d51a715d7a1181cd246b50a091bf909eaa04eae0;hp=9d5232334bc5ad805f449faa3d51249644689b4e;hpb=2f1d864660ff740773ea2c36ab79a837000f6452;p=spline3.git

diff --git a/src/FunctionValues.hs b/src/FunctionValues.hs
index 9d52323..0d84801 100644
--- a/src/FunctionValues.hs
+++ b/src/FunctionValues.hs
@@ -1,61 +1,62 @@
+{-# LANGUAGE BangPatterns #-}
+
 -- | The FunctionValues module contains the 'FunctionValues' type and
 --   the functions used to manipulate it.
+--
 module FunctionValues (
-  FunctionValues,
+  FunctionValues(..),
   empty_values,
   eval,
   make_values,
   rotate,
   function_values_tests,
   function_values_properties,
-  value_at
-  )
+  value_at )
 where
 
-import Prelude hiding (LT)
-import Test.HUnit
-import Test.Framework (Test, testGroup)
-import Test.Framework.Providers.HUnit (testCase)
-import Test.Framework.Providers.QuickCheck2 (testProperty)
-import Test.QuickCheck (Arbitrary(..), choose)
+import Prelude hiding ( LT )
+import Test.Tasty ( TestTree, testGroup )
+import Test.Tasty.HUnit ( Assertion, testCase )
+import Test.Tasty.QuickCheck ( Arbitrary( arbitrary ), choose, testProperty )
 
-import Assertions (assertTrue)
+import Assertions ( assertTrue )
 import Cardinal ( Cardinal(..), cwx, cwy, cwz )
-import Examples (trilinear)
-import Values (Values3D, dims, idx)
+import Examples ( trilinear )
+import Values ( Values3D, dims, idx )
 
 -- | The FunctionValues type represents the value of our function f at
 --   the 27 points surrounding (and including) the center of a
 --   cube. Each value of f can be accessed by the name of its
 --   direction.
+--
 data FunctionValues =
-    FunctionValues { front  :: Double,
-                     back   :: Double,
-                     left   :: Double,
-                     right  :: Double,
-                     top    :: Double,
-                     down   :: Double,
-                     front_left :: Double,
-                     front_right :: Double,
-                     front_down :: Double,
-                     front_top :: Double,
-                     back_left :: Double,
-                     back_right :: Double,
-                     back_down :: Double,
-                     back_top :: Double,
-                     left_down :: Double,
-                     left_top :: Double,
-                     right_down :: Double,
-                     right_top :: Double,
-                     front_left_down :: Double,
-                     front_left_top :: Double,
-                     front_right_down :: Double,
-                     front_right_top :: Double,
-                     back_left_down :: Double,
-                     back_left_top :: Double,
-                     back_right_down :: Double,
-                     back_right_top :: Double,
-                     interior :: Double }
+    FunctionValues { front              :: !Double,
+                     back               :: !Double,
+                     left               :: !Double,
+                     right              :: !Double,
+                     top                :: !Double,
+                     down               :: !Double,
+                     front_left         :: !Double,
+                     front_right        :: !Double,
+                     front_down         :: !Double,
+                     front_top          :: !Double,
+                     back_left          :: !Double,
+                     back_right         :: !Double,
+                     back_down          :: !Double,
+                     back_top           :: !Double,
+                     left_down          :: !Double,
+                     left_top           :: !Double,
+                     right_down         :: !Double,
+                     right_top          :: !Double,
+                     front_left_down    :: !Double,
+                     front_left_top     :: !Double,
+                     front_right_down   :: !Double,
+                     front_right_top    :: !Double,
+                     back_left_down     :: !Double,
+                     back_left_top      :: !Double,
+                     back_right_down    :: !Double,
+                     back_right_top     :: !Double,
+                     interior           :: !Double }
       deriving (Eq, Show)
 
 
@@ -135,6 +136,7 @@ empty_values :: FunctionValues
 empty_values =
     FunctionValues 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
 
+
 -- | The eval function is where the magic happens for the
 --   FunctionValues type. Given a 'Cardinal' direction and a
 --   'FunctionValues' object, eval will return the value of the
@@ -175,6 +177,7 @@ eval f (Difference x y) = (eval f x) - (eval f y)
 eval f (Product x y) = (eval f x) * (eval f y)
 eval f (Quotient x y) = (eval f x) / (eval f y)
 
+
 -- | Takes a three-dimensional list of 'Double' and a set of 3D
 --   coordinates (i,j,k), and returns the value at (i,j,k) in the
 --   supplied list. If there is no such value, we calculate one
@@ -195,68 +198,77 @@ eval f (Quotient x y) = (eval f x) / (eval f y)
 --   1.0
 --
 --   >>> value_at Examples.trilinear 1 3 0
---   4.0
+--   5.0
 --
 value_at :: Values3D -> Int -> Int -> Int -> Double
-value_at v3d i j k
+value_at v3d !i !j !k
   -- Put the most common case first!
-  | (i >= 0) && (j >= 0) && (k >= 0) =
+  | (valid_i i) && (valid_j j) && (valid_k k) =
       idx v3d i j k
 
-  -- The next three are from the first line in (7.3).
-  | (i == -1) && (j >= 0) && (k >= 0) =
-      2*(value_at v3d 0 j k) - (value_at v3d 1 j k)
-
-  | (i >= 0) && (j == -1) && (k >= 0) =
-      2*(value_at v3d i 0 k) - (value_at v3d i 1 k)
-
-  | (i >= 0) && (j >= 0) && (k == -1) =
-      2*(value_at v3d i j 0) - (value_at v3d i j 1)
-
-  -- The next two are from the second line in (7.3).
-  | (i == -1) && (j == -1) && (k >= 0) =
-      2*(value_at v3d i 0 k) - (value_at v3d i 1 k)
-
-  | (i == -1) && (j == ysize) && (k >= 0) =
-      2*(value_at v3d i (ysize - 1) k) - (value_at v3d i (ysize - 2) k)
-
-  -- The next two are from the third line in (7.3).
-  | (i == -1) && (j >= 0) && (k == -1) =
-      2*(value_at v3d i j 0) - (value_at v3d i j 1)
-
-  | (i == -1) && (j >= 0) && (k == zsize) =
-      2*(value_at v3d i j (zsize - 1)) - (value_at v3d i j (zsize - 2))
-
-  -- Repeat the above (j and k) cases for i >= 0.
-  | (i >= 0) && (j == -1) && (k == -1) =
-      2*(value_at v3d i j 0) - (value_at v3d i j 1)
+  -- The next three are from the first line in (7.3). Analogous cases
+  -- have been added where the indices are one-too-big. These are the
+  -- "one index is bad" cases.
+  | not (valid_i i) =
+      if (dim_i == 1)
+      then
+        -- We're one-dimensional in our first coordinate, so just
+        -- return the data point that we do have. If we try to use
+        -- the formula from remark 7.3, we go into an infinite loop.
+        value_at v3d 0 j k
+      else
+        if (i == -1)
+        then
+          2*(value_at v3d 0 j k) - (value_at v3d 1 j k)
+        else
+          2*(value_at v3d (i-1) j k) - (value_at v3d (i-2) j k)
+
+  | not (valid_j j) =
+      if (dim_j == 1)
+      then
+        -- We're one-dimensional in our second coordinate, so just
+        -- return the data point that we do have. If we try to use
+        -- the formula from remark 7.3, we go into an infinite loop.
+        value_at v3d i 0 k
+      else
+        if (j == -1)
+        then
+          2*(value_at v3d i 0 k) - (value_at v3d i 1 k)
+        else
+          2*(value_at v3d i (j-1) k) - (value_at v3d i (j-2) k)
+
+  | not (valid_k k) =
+      if (dim_k == 1)
+      then
+        -- We're one-dimensional in our third coordinate, so just
+        -- return the data point that we do have. If we try to use
+        -- the formula from remark 7.3, we go into an infinite loop.
+        value_at v3d i j 0
+      else
+        if (k == -1)
+        then
+          2*(value_at v3d i j 0) - (value_at v3d i j 1)
+        else
+          2*(value_at v3d i j (k-1)) - (value_at v3d i j (k-2))
+  where
+    (dim_i, dim_j, dim_k) = dims v3d
 
-  | (i == xsize) && (j == -1) && (k >= 0) =
-      2*(value_at v3d (xsize - 1) j k) - (value_at v3d (xsize - 2) j k)
+    valid_i :: Int -> Bool
+    valid_i i' = (i' >= 0) && (i' < dim_i)
 
-  -- These two cases I made up.
-  | (i == -1) && (j == -1) && (k == -1) =
-      2*(value_at v3d i j 0) - (value_at v3d i j 1)
+    valid_j :: Int -> Bool
+    valid_j j' = (j' >= 0) && (j' < dim_j)
 
-  | (i == xsize) && (j == ysize) && (k == zsize) =
-      2*(value_at v3d i j (zsize - 1)) - (value_at v3d i j (zsize - 2))
+    valid_k :: Int -> Bool
+    valid_k k' = (k' >= 0) && (k' < dim_k)
 
-  | otherwise =
-      let istr = show i
-          jstr = show j
-          kstr = show k
-          coordstr = "(" ++ istr ++ "," ++ jstr ++ "," ++ kstr ++ ")"
-      in
-        error $ "value_at called outside of domain: " ++ coordstr
-  where
-    (xsize, ysize, zsize) = dims v3d
 
 
 -- | Given a three-dimensional list of 'Double' and a set of 3D
 --   coordinates (i,j,k), constructs and returns the 'FunctionValues'
 --   object centered at (i,j,k)
 make_values :: Values3D -> Int -> Int -> Int -> FunctionValues
-make_values values i j k =
+make_values values !i !j !k =
     empty_values { front  = value_at values (i-1) j k,
                    back   = value_at values (i+1) j k,
                    left   = value_at values i (j-1) k,
@@ -357,9 +369,9 @@ test_directions =
                          back_right_top fvs == 15]
 
 
-function_values_tests :: Test.Framework.Test
+function_values_tests :: TestTree
 function_values_tests =
-    testGroup "FunctionValues Tests"
+    testGroup "FunctionValues tests"
                   [ testCase "test directions" test_directions ]
 
 
@@ -415,14 +427,24 @@ prop_z_rotation_doesnt_affect_top fv0 =
       expr2 = top fv1
 
 
-function_values_properties :: Test.Framework.Test
+function_values_properties :: TestTree
 function_values_properties =
-  let tp = testProperty
-  in
-    testGroup "FunctionValues Properties" [
-      tp "x rotation doesn't affect front" prop_x_rotation_doesnt_affect_front,
-      tp "x rotation doesn't affect back" prop_x_rotation_doesnt_affect_back,
-      tp "y rotation doesn't affect left" prop_y_rotation_doesnt_affect_left,
-      tp "y rotation doesn't affect right" prop_y_rotation_doesnt_affect_right,
-      tp "z rotation doesn't affect top" prop_z_rotation_doesnt_affect_top,
-      tp "z rotation doesn't affect down" prop_z_rotation_doesnt_affect_down ]
+  testGroup "FunctionValues properties" [
+    testProperty
+      "x rotation doesn't affect front"
+      prop_x_rotation_doesnt_affect_front,
+    testProperty
+      "x rotation doesn't affect back"
+      prop_x_rotation_doesnt_affect_back,
+    testProperty
+      "y rotation doesn't affect left"
+      prop_y_rotation_doesnt_affect_left,
+    testProperty
+      "y rotation doesn't affect right"
+      prop_y_rotation_doesnt_affect_right,
+    testProperty
+      "z rotation doesn't affect top"
+      prop_z_rotation_doesnt_affect_top,
+    testProperty
+      "z rotation doesn't affect down"
+      prop_z_rotation_doesnt_affect_down ]