X-Git-Url: http://gitweb.michael.orlitzky.com/?a=blobdiff_plain;f=src%2FTetrahedron.hs;h=bcf9a0b599b9fe36098663b71966445ac602bbb6;hb=9b9acc3fbb79d737a39a9f4def70621440933095;hp=81fe91c11772122d0643b884e4fc3aea52163a43;hpb=6fb9ab6b6068870323e996da931fc04c7710e3e4;p=spline3.git

diff --git a/src/Tetrahedron.hs b/src/Tetrahedron.hs
index 81fe91c..bcf9a0b 100644
--- a/src/Tetrahedron.hs
+++ b/src/Tetrahedron.hs
@@ -76,6 +76,11 @@ beta t i j k l
     b3_term = (b3 t) `fexp` l
 
 
+-- | The coefficient function. c t i j k l returns the coefficient
+--   c_ijkl with respect to the tetrahedron t. The definition uses
+--   pattern matching to mimic the definitions given in Sorokina and
+--   Zeilfelder, pp. 84-86. If incorrect indices are supplied, the
+--   function will simply error.
 c :: Tetrahedron -> Int -> Int -> Int -> Int -> Double
 c t 0 0 3 0 = eval (fv t) $
               (1/8) * (I + F + L + T + LT + FL + FT + FLT)
@@ -197,8 +202,10 @@ c _ _ _ _ _ = error "coefficient index out of bounds"
 
 
 
+-- | The matrix used in the tetrahedron volume calculation as given in
+--   Lai & Schumaker, Definition 15.4, page 436.
 vol_matrix :: Tetrahedron -> Matrix Double
-vol_matrix t = (4><4) $
+vol_matrix t = (4><4)
                [1,  1,  1,  1,
                 x1, x2, x3, x4,
                 y1, y2, y3, y4,
@@ -217,8 +224,8 @@ vol_matrix t = (4><4) $
       z3 = z_coord (v2 t)
       z4 = z_coord (v3 t)
 
--- Computed using the formula from Lai & Schumaker, Definition 15.4,
--- page 436.
+-- | Computed using the formula from Lai & Schumaker, Definition 15.4,
+--   page 436.
 volume :: Tetrahedron -> Double
 volume t
        | (v0 t) == (v1 t) = 0
@@ -230,21 +237,28 @@ volume t
        | otherwise = (1/6)*(det (vol_matrix t))
 
 
+-- | The barycentric coordinates of a point with respect to v0.
 b0 :: Tetrahedron -> (RealFunction Point)
 b0 t point = (volume inner_tetrahedron) / (volume t)
              where
                inner_tetrahedron = t { v0 = point }
 
+
+-- | The barycentric coordinates of a point with respect to v1.
 b1 :: Tetrahedron -> (RealFunction Point)
 b1 t point = (volume inner_tetrahedron) / (volume t)
              where
                inner_tetrahedron = t { v1 = point }
 
+
+-- | The barycentric coordinates of a point with respect to v2.
 b2 :: Tetrahedron -> (RealFunction Point)
 b2 t point = (volume inner_tetrahedron) / (volume t)
              where
                inner_tetrahedron = t { v2 = point }
 
+
+-- | The barycentric coordinates of a point with respect to v3.
 b3 :: Tetrahedron -> (RealFunction Point)
 b3 t point = (volume inner_tetrahedron) / (volume t)
              where