Convert the polynomial sum to a vector sum.

diff --git a/src/Tetrahedron.hs b/src/Tetrahedron.hs
index 5b459fea2870de5c2fed88ee9f9e5b57c7e5cfc9..87332b94440afdb999b173c13f681095d48ac796 100644 (file)
--- a/src/Tetrahedron.hs
+++ b/src/Tetrahedron.hs
@@ -1,6 +1,11 @@
 module Tetrahedron
 where
 
+import qualified Data.Vector as V (
+  singleton,
+  snoc,
+  sum
+  )
 import Numeric.LinearAlgebra hiding (i, scale)
 import Prelude hiding (LT)
 import Test.QuickCheck (Arbitrary(..), Gen, choose)
@@ -86,11 +91,26 @@ instance ThreeDimensional Tetrahedron where
 
 polynomial :: Tetrahedron -> (RealFunction Point)
 polynomial t =
-    sum [ (c t i j k l) `cmult` (beta t i j k l) | i <- [0..3],
-                                                   j <- [0..3],
-                                                   k <- [0..3],
-                                                   l <- [0..3],
-                                                   i + j + k + l == 3]
+    V.sum $ V.singleton ((c t 0 0 0 3) `cmult` (beta t 0 0 0 3)) `V.snoc`
+            ((c t 0 0 1 2) `cmult` (beta t 0 0 1 2)) `V.snoc`
+            ((c t 0 0 2 1) `cmult` (beta t 0 0 2 1)) `V.snoc`
+            ((c t 0 0 3 0) `cmult` (beta t 0 0 3 0)) `V.snoc`
+            ((c t 0 1 0 2) `cmult` (beta t 0 1 0 2)) `V.snoc`
+            ((c t 0 1 1 1) `cmult` (beta t 0 1 1 1)) `V.snoc`
+            ((c t 0 1 2 0) `cmult` (beta t 0 1 2 0)) `V.snoc`
+            ((c t 0 2 0 1) `cmult` (beta t 0 2 0 1)) `V.snoc`
+            ((c t 0 2 1 0) `cmult` (beta t 0 2 1 0)) `V.snoc`
+            ((c t 0 3 0 0) `cmult` (beta t 0 3 0 0)) `V.snoc`
+            ((c t 1 0 0 2) `cmult` (beta t 1 0 0 2)) `V.snoc`
+            ((c t 1 0 1 1) `cmult` (beta t 1 0 1 1)) `V.snoc`
+            ((c t 1 0 2 0) `cmult` (beta t 1 0 2 0)) `V.snoc`
+            ((c t 1 1 0 1) `cmult` (beta t 1 1 0 1)) `V.snoc`
+            ((c t 1 1 1 0) `cmult` (beta t 1 1 1 0)) `V.snoc`
+            ((c t 1 2 0 0) `cmult` (beta t 1 2 0 0)) `V.snoc`
+            ((c t 2 0 0 1) `cmult` (beta t 2 0 0 1)) `V.snoc`
+            ((c t 2 0 1 0) `cmult` (beta t 2 0 1 0)) `V.snoc`
+            ((c t 2 1 0 0) `cmult` (beta t 2 1 0 0)) `V.snoc`
+            ((c t 3 0 0 0) `cmult` (beta t 3 0 0 0))
 
 
 -- | Returns the domain point of t with indices i,j,k,l.