From: leicht <leicht@0785d39b-7218-0410-832d-ea1e28bc413d>
Date: Thu, 16 Aug 2007 07:43:30 +0000 (+0000)
Subject: New test, that currently fails: The neighbor_of_neighbor function does not work prope... 
X-Git-Url: https://gitweb.dealii.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=4b5ea9f4a388b09451755a0b5fd73b00e306bd3f;p=dealii-svn.git

New test, that currently fails: The neighbor_of_neighbor function does not work properly if two cells are neighbors at more than one face.

git-svn-id: https://svn.dealii.org/trunk@14963 0785d39b-7218-0410-832d-ea1e28bc413d
---

diff --git a/tests/bits/Makefile b/tests/bits/Makefile
index a4d698ccab..164ba8b138 100644
--- a/tests/bits/Makefile
+++ b/tests/bits/Makefile
@@ -89,7 +89,8 @@ tests_x = grid_generator_?? \
 	  tria_crash_* \
 	  face_orientation_* \
 	  max_n_cells_* \
-	  joa_*
+	  joa_* \
+	  neighboring_cells_at_two_faces 
 
 # tests for the hp branch:
 #	  fe_collection_*
diff --git a/tests/bits/neighboring_cells_at_two_faces.cc b/tests/bits/neighboring_cells_at_two_faces.cc
new file mode 100644
index 0000000000..fa34fffa35
--- /dev/null
+++ b/tests/bits/neighboring_cells_at_two_faces.cc
@@ -0,0 +1,101 @@
+//---------------  neighboring_cells_at_two_faces.cc  ----------------
+//    $Id$
+//    Version: $Name$ 
+//
+//    Copyright (C) 2007 by the deal.II authors
+//
+//    This file is subject to QPL and may not be  distributed
+//    without copyright and license information. Please refer
+//    to the file deal.II/doc/license.html for the  text  and
+//    further information on this license.
+//
+//---------------  neighboring_cells_at_two_faces.cc  ----------------
+
+#include "../tests.h"
+#include <base/logstream.h>
+#include <base/geometry_info.h>
+#include <grid/tria.h>
+#include <grid/tria_accessor.h>
+#include <grid/tria_iterator.h>
+#include <grid/grid_reordering.h>
+
+#include <fstream>
+#include <iostream>
+
+
+// generate two degenerate quads which reduce to the form of triangles, where
+// two sides of the quad form one side of the triangle. the neighboring quads
+// are neighboring along both of these sides.
+//
+//  *-------*
+//  |1     /|
+//  |    a/ |
+//  |    /  |
+//  |   *   |
+//  |  /    |
+//  | /b    |
+//  |/     2|
+//  *-------*
+//
+// looking from cell 1 at face a and asking for the corresponding face (number)
+// of cell 2 neighbor_of_neighbor returns something corrwesponding to face b,
+// not a, as it should. Simply looking at the identity of the neighboring cell
+// is not enough, we have to look at the (index of the) face instead.
+
+void create_grid (Triangulation<2> &tria)
+{
+  const unsigned int n_points=5;
+  
+  const Point<2> points[n_points] = { Point<2>(0.0,0.0),
+                               Point<2>(1.0,1.0),
+                               Point<2>(2.0,2.0),
+                               Point<2>(0.0,2.0),
+                               Point<2>(2.0,0.0)};
+  std::vector<Point<2> > vertices(n_points);
+  vertices.assign(points,points+n_points);
+
+  std::vector<CellData<2> > cells(2);
+  cells[0].vertices[0]   = 0;
+  cells[0].vertices[1]   = 1;
+  cells[0].vertices[2]   = 2;
+  cells[0].vertices[3]   = 3;
+  cells[1].vertices[0]   = 0;
+  cells[1].vertices[1]   = 4;
+  cells[1].vertices[2]   = 2;
+  cells[1].vertices[3]   = 1;
+
+                                   // generate a triangulation
+                                   // out of this
+  GridReordering<2>::reorder_cells (cells);
+  tria.create_triangulation_compatibility (vertices, cells, SubCellData());
+}
+
+
+void check_neighbors (const Triangulation<2> &tria)
+{
+  Triangulation<2>::cell_iterator cell = tria.begin();
+  for (unsigned int f=0; f<GeometryInfo<2>::faces_per_cell; ++f)
+    if (cell->neighbor(f).state()==IteratorState::valid)
+      {
+	const unsigned int neighbor_neighbor=cell->neighbor_of_neighbor(f);
+	deallog << "At face " << f << ": neighbor_of_neighbor="
+		<< neighbor_neighbor << std::endl;
+	Assert(cell->face(f)==cell->neighbor(f)->face(neighbor_neighbor),
+	       ExcMessage("Error in neighbor_of_neighbor() function!"));
+      }
+}
+
+
+
+int main()
+{
+  std::ofstream logfile("neighboring_cells_at_two_faces/output");
+  deallog.attach(logfile);
+  deallog.depth_console(0);
+  deallog.threshold_double(1.e-10);
+  
+  Triangulation<2> tria;
+  create_grid(tria);
+  check_neighbors(tria);
+}
+
diff --git a/tests/bits/neighboring_cells_at_two_faces/cmp/generic b/tests/bits/neighboring_cells_at_two_faces/cmp/generic
new file mode 100644
index 0000000000..576ed308b8
--- /dev/null
+++ b/tests/bits/neighboring_cells_at_two_faces/cmp/generic
@@ -0,0 +1,3 @@
+
+DEAL::At face 1: neighbor_of_neighbor=3
+DEAL::At face 2: neighbor_of_neighbor=0