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include/poly_utils.h

@@ -1091,9 +1091,9 @@ namespace dealii::PolyUtils
         const FiniteElement<dim, spacedim> &original_fe =
           agglomeration_handler.get_fe();
 
-        // We use DGQ nodal elements of the same degree as the ones in the
-        // agglomeration handler to generate the output also in the case in
-        // which different elements are used, such as DGP.
+        // We use DGQ (on tensor-product meshes) or DGP (on simplex meshes)
+        // nodal elements of the same degree as the ones in the agglomeration
+        // handler to interpolate the solution onto the finer grid.
         std::unique_ptr<FiniteElement<dim>> output_fe;
         if (tria.all_reference_cells_are_hyper_cube())
           output_fe = std::make_unique<FE_DGQ<dim>>(original_fe.degree);