[discretefunction.bochner] some updates

* update ListVectorArray usage
* add preliminary visualization

dune/gdt/discretefunction/bochner.hh

@@ -15,6 +15,7 @@
 #include <dune/xt/grid/search.hh>
 
 #include <dune/gdt/exceptions.hh>
+#include <dune/gdt/discretefunction/default.hh>
 #include <dune/gdt/spaces/bochner.hh>
 
 namespace Dune {
@@ -23,31 +24,37 @@ namespace GDT {
 
 /**
  * \todo Turn this into a parametric LocalizableFunction.
+ * \todo add ConstDiscreteBochnerFunction
  */
 template <class V, class GV, size_t r = 1, size_t rC = 1, class R = double>
 class DiscreteBochnerFunction
 {
 public:
-  DiscreteBochnerFunction(const BochnerSpace<GV, r, rC, R>& bochner_space, XT::LA::ListVectorArray<V>& dof_vectors)
+  DiscreteBochnerFunction(const BochnerSpace<GV, r, rC, R>& bochner_space,
+                          XT::LA::ListVectorArray<V>& dof_vectors,
+                          const std::string nm = "")
     : bochner_space_(bochner_space)
     , dof_vectors_(dof_vectors)
+    , name_(nm.empty() ? "DiscreteBochnerFunction" : nm)
   {
     DUNE_THROW_IF(this->dof_vectors().length() != bochner_space_.temporal_space().mapper().size(),
                   Exceptions::space_error,
                   "\n   this->dof_vectors().length() = " << this->dof_vectors().length() << "\n   "
                                                          << bochner_space_.temporal_space().mapper().size());
     for (const auto& vec : this->dof_vectors())
-      DUNE_THROW_IF(vec.size() != bochner_space_.spatial_space().mapper().size(),
+      DUNE_THROW_IF(vec.vector().size() != bochner_space_.spatial_space().mapper().size(),
                     Exceptions::space_error,
-                    "\n   vec.size() = " << vec.size() << "\n   " << bochner_space_.spatial_space().mapper().size());
+                    "\n   vec.vector().size() = " << vec.vector().size() << "\n   "
+                                                  << bochner_space_.spatial_space().mapper().size());
   } // DiscreteBochnerFunction(...)
 
-  DiscreteBochnerFunction(const BochnerSpace<GV, r, rC, R>& bochner_space)
+  DiscreteBochnerFunction(const BochnerSpace<GV, r, rC, R>& bochner_space, const std::string nm = "")
     : bochner_space_(bochner_space)
     , dof_vectors_(new XT::LA::ListVectorArray<V>(bochner_space_.spatial_space().mapper().size(),
                                                   bochner_space_.temporal_space().mapper().size()))
+    , name_(nm.empty() ? "DiscreteBochnerFunction" : nm)
   {
-  } // DiscreteBochnerFunction(...)
+  }
 
   const BochnerSpace<GV, r, rC, R>& space() const
   {
@@ -64,6 +71,11 @@ public:
     return dof_vectors_.access();
   }
 
+  std::string name() const
+  {
+    return name_;
+  }
+
   V evaluate(const double& time) const
   {
     const auto search_result = XT::Grid::make_entity_in_level_search(bochner_space_.temporal_space().grid_view())(
@@ -78,13 +90,25 @@ public:
     V result(bochner_space_.spatial_space().mapper().size(), 0.);
     const auto global_dof_indices = bochner_space_.temporal_space().mapper().global_indices(time_interval);
     for (size_t ii = 0; ii < temporal_basis->size(); ++ii)
-      result.axpy(temporal_basis_values[ii], this->dof_vectors()[global_dof_indices[ii]]);
+      result.axpy(temporal_basis_values[ii], this->dof_vectors()[global_dof_indices[ii]].vector());
     return result;
   } // ... evaluate(...)
 
+  void visualize(const std::string filename_prefix, const VTK::OutputType vtk_output_type = VTK::appendedraw) const
+  {
+    DUNE_THROW_IF(
+        filename_prefix.empty(), XT::Common::Exceptions::wrong_input_given, "filename_prefix must not be empty!");
+    for (const auto& annotated_vector : dof_vectors_.access()) {
+      const double time = annotated_vector.note().get("_t").at(0);
+      auto df = make_const_discrete_function(bochner_space_.spatial_space(), annotated_vector.vector(), name_);
+      df.visualize(filename_prefix + "_" + XT::Common::to_string(time), vtk_output_type);
+    }
+  } // ... visualize(...)
+
 private:
   const BochnerSpace<GV, r, rC, R>& bochner_space_;
   XT::Common::StorageProvider<XT::LA::ListVectorArray<V>> dof_vectors_;
+  const std::string name_;
 }; // class DiscreteBochnerFunction