created a test for tesing the cubic interpolation

lib/grid/__init__.py

@@ -88,9 +88,9 @@ class grid(object):
     (dist, indicies) = self.tree.query(X, 2)
 
     simplex = None
-    for i in self.facets_for_point[indicies[0]]:
-      if i.contains(X, self):
-        simplex = i
+    for facet in self.facets_for_point[indicies[0]]:
+      if facet.contains(X, self):
+        simplex = facet
         break
 
     if not simplex:

lib/grid/simplex.py

@@ -1,13 +1,17 @@
 from baker import get_phis
 
-TOL = 1e-3
+TOL = 1e-8
 
 def contains(X, R):
-    phis = get_phis(X, R)
-    r = True
-    if [i for i in phis if i < 0.0 - TOL]:
-      r = False
-    return r
+  """
+    tests if X (point) is in R (a simplex,
+    represented by a list of n-degree coordinates)
+  """
+  phis = get_phis(X, R)
+  r = True
+  if [i for i in phis if i < 0.0 - TOL]:
+    r = False
+  return r
 
 
 class face(object):
@@ -28,8 +32,18 @@ class face(object):
     """
     self.neighbors.append(n)
 
-  def contains(self, X, grid):
-    return contains(X, grid.points)
+  def contains(self, X, G):
+    """
+      X = point of interest
+      G = corrensponding grid object (G.points)
+      because of the way i'm storing things,
+      a face simply stores indicies, and so one
+      must pass in a reference to the grid object
+      containing real points.
+
+      this simply calls grid.simplex.contains
+    """
+    return contains(X, [G.points[i] for i in self.verts])
 
   def __str__(self):
     neighbors = [i.name for i in self.neighbors]