Fix problems with exercise04

tutorial04/exercise/src/driver.hh

-/********************************************************/
-// Beware of line number changes, they may corrupt docu!
-//! \brief Driver function to set up and solve the problem
-/********************************************************/
+#define _STRINGIZE(STR) #STR
+#define STRINGIZE(STR) _STRINGIZE(STR)
+
+
 
 template<typename GV, typename FEM>
 void driver (const GV& gv, const FEM& fem,
@@ -69,7 +69,7 @@ void driver (const GV& gv, const FEM& fem,
   int subsampling=ptree.get("output.subsampling",(int)0);
   using VTKWRITER = Dune::SubsamplingVTKWriter<GV>;
   VTKWRITER vtkwriter(gv,subsampling);
-  std::string filename=ptree.get("output.filename","output") + ptree.get("grid.dim","grid") + "d";
+  std::string filename=ptree.get("output.filename","output") + STRINGIZE(GRIDDIM) "d";
   struct stat st;
   if( stat( filename.c_str(), &st ) != 0 )
     {

tutorial04/exercise/src/exercise04.cc

@@ -29,6 +29,7 @@
 // dune-istl included by pdelab
 // dune-pdelab includes
 #include<dune/pdelab/common/function.hh>
+#include<dune/pdelab/common/functionutilities.hh>
 #include<dune/pdelab/common/vtkexport.hh>
 #include<dune/pdelab/finiteelementmap/pkfem.hh>
 #include<dune/pdelab/finiteelementmap/qkfem.hh>
@@ -36,6 +37,7 @@
 #include<dune/pdelab/constraints/common/constraintsparameters.hh>
 #include<dune/pdelab/constraints/conforming.hh>
 #include<dune/pdelab/function/callableadapter.hh>
+#include<dune/pdelab/function/sqr.hh>
 #include<dune/pdelab/gridfunctionspace/gridfunctionspace.hh>
 #include<dune/pdelab/gridfunctionspace/gridfunctionspaceutilities.hh>
 #include<dune/pdelab/gridfunctionspace/subspace.hh>

tutorial04/exercise/src/exercise04.ini

 [grid]
-refinement=5
+refinement=4
 
 [grid.structured]
 LX=2.5