--- a/+scheme/Scheme.m	Fri Feb 26 16:06:52 2016 +0100
+++ b/+scheme/Scheme.m	Fri Feb 26 16:21:47 2016 +0100
@@ -21,11 +21,10 @@
         % Penalty functions return the opertors to force the solution. In the case of an interface it returns the operator applied to the other doamin.
         %       boundary            is a string specifying the boundary e.g. 'l','r' or 'e','w','n','s'.
         %       type                is a string specifying the type of boundary condition if there are several.
-        %       data                is a function returning the data that should be applied at the boundary.
         %       neighbour_scheme    is an instance of Scheme that should be interfaced to.
         %       neighbour_boundary  is a string specifying which boundary to interface to.
-        m = boundary_condition(obj,boundary,type,data)
-        m = interface(obj,boundary,neighbour_scheme,neighbour_boundary)
+        [closure, penalty] = boundary_condition(obj,boundary,type)
+        [closure, penalty] = interface(obj,boundary,neighbour_scheme,neighbour_boundary)
         N = size(obj) % Returns the number of degrees of freedom.
 
     end