minor change in extensions/demo/NavierStokesCahnHilliard_PC/src/CahnHilliardNavierStokes_.h

extensions/demo/NavierStokesCahnHilliard_PC/src/CahnHilliardNavierStokes_.h

@@ -20,6 +20,15 @@ using namespace AMDiS;
 
 
 
+class ID : public AbstractFunction<double, double>
+{
+public:
+  ID()
+    : AbstractFunction<double, double>(2)  {};
+  double operator()(const double& x) const  {
+    return x;
+  }
+};