From 610d0f0af8a802c26d51231d6e2426a72e40fd2d Mon Sep 17 00:00:00 2001
From: Michael Orlitzky <michael@orlitzky.com>
Date: Tue, 25 Oct 2011 17:25:17 -0400
Subject: [PATCH] Remove the Point.distance function and associated assertion.
 We only need the dot product.

---
 src/Assertions.hs | 10 +---------
 src/Cube.hs       |  5 +++--
 src/Grid.hs       |  4 ++--
 src/Point.hs      | 14 --------------
 4 files changed, 6 insertions(+), 27 deletions(-)

diff --git a/src/Assertions.hs b/src/Assertions.hs
index b2ec7c1..4e09b82 100644
--- a/src/Assertions.hs
+++ b/src/Assertions.hs
@@ -10,7 +10,7 @@ import Test.HUnit (Assertion,
                    assertFailure)
 
 import Comparisons ((~=))
-import Point (Point, is_close)
+
 
 -- | An HUnit assertion that wraps the almost_equals function. Stolen
 --   from the definition of 'assertEqual' in Test\/HUnit\/Base.hs.
@@ -21,14 +21,6 @@ assertAlmostEqual preface expected actual =
                 "expected: " ++ show expected ++ "\n but got: " ++ show actual
 
 
--- | An HUnit assertion that wraps the is_close function. Stolen
---   from the definition of 'assertEqual' in Test\/HUnit\/Base.hs.
-assertClose :: String -> Point -> Point -> Assertion
-assertClose preface expected actual =
-  unless (actual `is_close` expected) (assertFailure msg)
-    where msg = (if null preface then "" else preface ++ "\n") ++
-                "expected: " ++ show expected ++ "\n but got: " ++ show actual
-
 
 -- | It's asinine that this doesn't exist already.
 assertTrue :: String -> Bool -> Assertion
diff --git a/src/Cube.hs b/src/Cube.hs
index 32b4b65..1c654ff 100644
--- a/src/Cube.hs
+++ b/src/Cube.hs
@@ -655,8 +655,9 @@ find_containing_tetrahedron cube p =
           else
             back_right_down_tetrahedra cube
 
-    -- Use the dot product instead of 'distance' here to save a
-    -- sqrt(). So, "distances" below really means "distances squared."
+    -- Use the dot product instead of Euclidean distance here to save
+    -- a sqrt(). So, "distances" below really means "distances
+    -- squared."
     distances = V.map ((dot p) . center) candidates
     shortest_distance = V.minimum distances
     lucky_idx = V.findIndex
diff --git a/src/Grid.hs b/src/Grid.hs
index 71e39a0..d5553b4 100644
--- a/src/Grid.hs
+++ b/src/Grid.hs
@@ -22,7 +22,7 @@ import Test.QuickCheck ((==>),
                         Positive(..),
                         Property,
                         choose)
-import Assertions (assertAlmostEqual, assertClose, assertTrue)
+import Assertions (assertAlmostEqual, assertTrue)
 import Comparisons ((~=))
 import Cube (Cube(Cube),
              find_containing_tetrahedron,
@@ -282,7 +282,7 @@ trilinear_c0_t0_tests =
 
     test_trilinear_f0_t0_v3 :: Assertion
     test_trilinear_f0_t0_v3 =
-      assertClose "v3 is correct" (v3 t) (0.5, 1.5, 1.5)
+      assertEqual "v3 is correct" (v3 t) (0.5, 1.5, 1.5)
 
 
 test_trilinear_reproduced :: Assertion
diff --git a/src/Point.hs b/src/Point.hs
index 4b9eaec..49ad534 100644
--- a/src/Point.hs
+++ b/src/Point.hs
@@ -2,9 +2,7 @@
 
 module Point (
   Point,
-  distance,
   dot,
-  is_close,
   scale
   )
 where
@@ -28,19 +26,7 @@ scale :: Point -> Double -> Point
 scale (x, y, z) d = (x*d, y*d, z*d)
 
 
--- | Returns the distance between p1 and p2.
-distance :: Point -> Point -> Double
-distance p1 p2 =
-    sqrt $ p1 `dot` p2
-
-
 -- | Returns the dot product of two points (taken as three-vectors).
 dot :: Point -> Point -> Double
 dot (x1, y1, z1) (x2, y2, z2) =
     (x2 - x1)^(2::Int) + (y2 - y1)^(2::Int) + (z2 - z1)^(2::Int)
-
-
--- | Returns 'True' if p1 is close to (within 'epsilon' of) p2,
---   'False' otherwise.
-is_close :: Point -> Point -> Bool
-is_close p1 p2 = (distance p1 p2) ~= 0
-- 
2.43.2