X-Git-Url: http://gitweb.michael.orlitzky.com/?a=blobdiff_plain;f=src%2FTetrahedron.hs;h=ad164d2426dce01e85cbf3d22cab0d0a19380410;hb=68b7d1002448a896236050caceb4f38463b996f4;hp=032ce1eb9855b821d8964c44a824b911c1765a59;hpb=89b8b6e94fcc944a1f4611811265f3c6217af850;p=spline3.git

diff --git a/src/Tetrahedron.hs b/src/Tetrahedron.hs
index 032ce1e..ad164d2 100644
--- a/src/Tetrahedron.hs
+++ b/src/Tetrahedron.hs
@@ -54,10 +54,15 @@ polynomial t =
 
 
 -- | Returns the domain point of t with indices i,j,k,l.
+--   Simply an alias for the domain_point function.
 xi :: Tetrahedron -> Int -> Int -> Int -> Int -> Point
-xi t i j k l
+xi = domain_point
+
+-- | Returns the domain point of t with indices i,j,k,l.
+domain_point :: Tetrahedron -> Int -> Int -> Int -> Int -> Point
+domain_point t i j k l
    | i + j + k + l == 3 = weighted_sum `scale` (1/3)
-   | otherwise = error "xi index out of bounds"
+   | otherwise = error "domain point index out of bounds"
    where
      v0' = (v0 t) `scale` (fromIntegral i)
      v1' = (v1 t) `scale` (fromIntegral j)
@@ -66,7 +71,6 @@ xi t i j k l
      weighted_sum = v0' + v1' + v2' + v3'
 
 
-
 -- | The Bernstein polynomial on t with indices i,j,k,l. Denoted by a
 --   capital 'B' in the Sorokina/Zeilfelder paper.
 beta :: Tetrahedron -> Int -> Int -> Int -> Int -> (RealFunction Point)