Make Main a little more amenable to changes.

[spline3.git] / src / FunctionValues.hs

diff --git a/src/FunctionValues.hs b/src/FunctionValues.hs
index 8eb5bdb0d375ffdfe72eabb81097cc99c121e563..e9da25ffc235171c89bd6b878162d681554d5e0a 100644 (file)
--- a/src/FunctionValues.hs
+++ b/src/FunctionValues.hs
@@ -1,12 +1,27 @@
 -- | The FunctionValues module contains the 'FunctionValues' type and
 --   the functions used to manipulate it.
-module FunctionValues
+module FunctionValues (
+  FunctionValues,
+  empty_values,
+  eval,
+  make_values,
+  rotate,
+  function_values_tests,
+  function_values_properties,
+  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 Cardinal
+import Assertions (assertTrue)
+import Cardinal ( Cardinal(..), cwx, cwy, cwz )
+import Examples (trilinear)
 import Values (Values3D, dims, idx)
 
 -- | The FunctionValues type represents the value of our function f at
@@ -164,14 +179,29 @@ eval f (Quotient x y) = (eval f x) / (eval f y)
 --   coordinates (i,j,k), and returns the value at (i,j,k) in the
 --   supplied list. If there is no such value, we choose a nearby
 --   point and use its value.
+--
+--   Examples:
+--
+--   >>> value_at Examples.trilinear 0 0 0
+--   1.0
+--
+--   >>> value_at Examples.trilinear (-1) 0 0
+--   1.0
+--
+--   >>> value_at Examples.trilinear 0 0 4
+--   1.0
+--
+--   >>> value_at Examples.trilinear 1 3 0
+--   4.0
+--
 value_at :: Values3D -> Int -> Int -> Int -> Double
 value_at v3d i j k
          | i < 0 = value_at v3d 0 j k
          | j < 0 = value_at v3d i 0 k
          | k < 0 = value_at v3d i j 0
-         | xsize <= i = value_at v3d xsize j k
-         | ysize <= j = value_at v3d i ysize k
-         | zsize <= k = value_at v3d i j zsize
+         | xsize <= i = value_at v3d (xsize - 1) j k
+         | ysize <= j = value_at v3d i (ysize - 1) k
+         | zsize <= k = value_at v3d i j (zsize - 1)
          | otherwise = idx v3d i j k
   where
     (xsize, ysize, zsize) = dims v3d
@@ -243,3 +273,111 @@ rotate rotation fv =
                      back_right_down = eval fv (rotation BRD),
                      back_right_top = eval fv (rotation BRT),
                      interior = interior fv }
+
+
+
+-- | Ensure that the trilinear values wind up where we think they
+--   should.
+test_directions :: Assertion
+test_directions =
+    assertTrue "all direction functions work" (and equalities)
+        where
+          fvs = make_values trilinear 1 1 1
+          equalities = [ interior fvs == 4,
+                         front fvs == 1,
+                         back  fvs == 7,
+                         left  fvs == 2,
+                         right fvs == 6,
+                         down  fvs == 3,
+                         top   fvs == 5,
+                         front_left fvs == 1,
+                         front_right fvs == 1,
+                         front_down fvs == 1,
+                         front_top fvs == 1,
+                         back_left fvs == 3,
+                         back_right fvs == 11,
+                         back_down fvs == 5,
+                         back_top fvs == 9,
+                         left_down fvs == 2,
+                         left_top fvs == 2,
+                         right_down fvs == 4,
+                         right_top fvs == 8,
+                         front_left_down fvs == 1,
+                         front_left_top fvs == 1,
+                         front_right_down fvs == 1,
+                         front_right_top fvs == 1,
+                         back_left_down fvs == 3,
+                         back_left_top fvs == 3,
+                         back_right_down fvs == 7,
+                         back_right_top fvs == 15]
+
+
+function_values_tests :: Test.Framework.Test
+function_values_tests =
+    testGroup "FunctionValues Tests"
+                  [ testCase "test directions" test_directions ]
+
+
+prop_x_rotation_doesnt_affect_front :: FunctionValues -> Bool
+prop_x_rotation_doesnt_affect_front fv0 =
+    expr1 == expr2
+    where
+      fv1 = rotate cwx fv0
+      expr1 = front fv0
+      expr2 = front fv1
+
+prop_x_rotation_doesnt_affect_back :: FunctionValues -> Bool
+prop_x_rotation_doesnt_affect_back fv0 =
+    expr1 == expr2
+    where
+      fv1 = rotate cwx fv0
+      expr1 = back fv0
+      expr2 = back fv1
+
+
+prop_y_rotation_doesnt_affect_left :: FunctionValues -> Bool
+prop_y_rotation_doesnt_affect_left fv0 =
+    expr1 == expr2
+    where
+      fv1 = rotate cwy fv0
+      expr1 = left fv0
+      expr2 = left fv1
+
+prop_y_rotation_doesnt_affect_right :: FunctionValues -> Bool
+prop_y_rotation_doesnt_affect_right fv0 =
+    expr1 == expr2
+    where
+      fv1 = rotate cwy fv0
+      expr1 = right fv0
+      expr2 = right fv1
+
+
+prop_z_rotation_doesnt_affect_down :: FunctionValues -> Bool
+prop_z_rotation_doesnt_affect_down fv0 =
+    expr1 == expr2
+    where
+      fv1 = rotate cwz fv0
+      expr1 = down fv0
+      expr2 = down fv1
+
+
+prop_z_rotation_doesnt_affect_top :: FunctionValues -> Bool
+prop_z_rotation_doesnt_affect_top fv0 =
+    expr1 == expr2
+    where
+      fv1 = rotate cwz fv0
+      expr1 = top fv0
+      expr2 = top fv1
+
+
+function_values_properties :: Test.Framework.Test
+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 ]