[GridOperator] Get the number of basis functions from the base

This avoids the need to use the reference elements, and is more correct.

Close: #33 (closed)

src/gridoperator.hh

@@ -12,8 +12,6 @@
 
 #include <dune/istl/bvector.hh>
 
-#include <dune/geometry/referenceelements.hh>
-
 #include "q1localbasis.hh"
 #include "sparsitypattern.hh"
 
@@ -85,9 +83,8 @@ namespace PPS {
       // Traverse grid view
       for (const auto& element : elements(gv_))
       {
-        // number of basis functions (same as number of sub-vertices in the
-        // grid element)
-        auto size = referenceElement(element.geometry()).size(element.dimension);
+        // number of basis functions
+        auto size = lb_.size();
 
         // make sure local containers have the correct size and are
         // initialized where needed
@@ -163,9 +160,8 @@ namespace PPS {
       // Traverse grid view
       for (const auto& element : elements(gv_))
       {
-        // number of basis functions (same as number of sub-vertices in the
-        // grid element)
-        auto size = referenceElement(element.geometry()).size(element.dimension);
+        // number of basis functions
+        auto size = lb_.size();
 
         // make sure local containers have the correct size and are
         // initialized where needed
@@ -222,9 +218,8 @@ namespace PPS {
       // Traverse grid view
       for (const auto& element : elements(gv_))
       {
-        // number of basis functions (same as number of sub-vertices in the
-        // grid element)
-        auto size = referenceElement(element.geometry()).size(element.dimension);
+        // number of basis functions
+        auto size = lb_.size();
 
         // make sure local containers have the correct size and are
         // initialized where needed