change do FLOAT64 as default data-type int Vtk::Function

dune/vtk/function.hh

@@ -82,7 +82,7 @@ namespace Dune
       {
         setComponents(std::move(components));
         setRangeType(getArg<Vtk::RangeTypes>(args..., Vtk::RangeTypes::UNSPECIFIED), components_.size());
-        setDataType(getArg<Vtk::DataTypes>(args..., Vtk::DataTypes::FLOAT32));
+        setDataType(getArg<Vtk::DataTypes>(args..., Vtk::DataTypes::FLOAT64));
       }
 
       /// (2) Construct from a LocalFunction directly
@@ -103,7 +103,7 @@ namespace Dune
         : Function(std::forward<LF>(localFct), std::move(name),
                    allComponents(getArg<int,unsigned int,long,unsigned long>(args..., sizeOf<R>())),
                    getArg<Vtk::RangeTypes>(args..., Vtk::RangeTypes::UNSPECIFIED),
-                   getArg<Vtk::DataTypes>(args..., Vtk::DataTypes::FLOAT32))
+                   getArg<Vtk::DataTypes>(args..., Vtk::DataTypes::FLOAT64))
       {}
 
       /// (3) Construct from a Vtk::Function
@@ -148,7 +148,7 @@ namespace Dune
       {
         setComponents(fct->ncomps());
 #if DUNE_VERSION_LT(DUNE_GRID,2,7)
-        setDataType(Vtk::DataTypes::FLOAT32);
+        setDataType(Vtk::DataTypes::FLOAT64);
 #else
         setDataType(dataTypeOf(fct->precision()));
 #endif
@@ -236,7 +236,7 @@ namespace Dune
       Vtk::LocalFunction<GridView> localFct_;
       std::string name_;
       std::vector<int> components_;
-      Vtk::DataTypes dataType_ = Vtk::DataTypes::FLOAT32;
+      Vtk::DataTypes dataType_ = Vtk::DataTypes::FLOAT64;
       Vtk::RangeTypes rangeType_ = Vtk::RangeTypes::UNSPECIFIED;
     };