From: Peter Munch <peterrmuench@gmail.com>
Date: Sat, 18 Sep 2021 18:11:32 +0000 (+0200)
Subject: HangingNodes: ignore artificial neighbors
X-Git-Tag: v9.4.0-rc1~980^2
X-Git-Url: https://gitweb.dealii.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=refs%2Fpull%2F12767%2Fhead;p=dealii.git

HangingNodes: ignore artificial neighbors
---

diff --git a/include/deal.II/matrix_free/hanging_nodes_internal.h b/include/deal.II/matrix_free/hanging_nodes_internal.h
index b92fcf2316..5ec5e367dd 100644
--- a/include/deal.II/matrix_free/hanging_nodes_internal.h
+++ b/include/deal.II/matrix_free/hanging_nodes_internal.h
@@ -374,6 +374,9 @@ namespace internal
                   {
                     const auto &neighbor = cell->neighbor(face);
 
+                    if (neighbor->is_artificial())
+                      continue;
+
                     // Neighbor is coarser than us, i.e., face is constrained
                     if (neighbor->level() < cell->level())
                       {
@@ -613,6 +616,10 @@ namespace internal
                           {
                             // If one of them is coarser than us
                             const auto neighbor_cell = edge_neighbor.first;
+
+                            if (neighbor_cell->is_artificial())
+                              continue;
+
                             if (neighbor_cell->level() < cell->level())
                               {
                                 const unsigned int local_line_neighbor =