From: bangerth Date: Wed, 8 May 2013 08:48:49 +0000 (+0000) Subject: Augment documentation. X-Git-Url: https://gitweb.dealii.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=a961696abb4d636ffe95bf71c5f4e7e4eb66cfb2;p=dealii-svn.git Augment documentation. git-svn-id: https://svn.dealii.org/trunk@29481 0785d39b-7218-0410-832d-ea1e28bc413d --- diff --git a/deal.II/include/deal.II/grid/grid_in.h b/deal.II/include/deal.II/grid/grid_in.h index d64585ee94..8a23c03805 100644 --- a/deal.II/include/deal.II/grid/grid_in.h +++ b/deal.II/include/deal.II/grid/grid_in.h @@ -43,8 +43,9 @@ struct SubCellData; * and hexahedra. A tool that can do this is tethex, see * http://code.google.com/p/tethex/wiki/Tethex . * - * Since the coarse mesh fed into a @p Triangulation object must not have - * hanging nodes, strange things will happen if the mesh represented by the + * The mesh you read will form the coarsest level of a @p Triangulation object. + * As such, it must not contain hanging nodes or other forms or adaptive + * refinement and strange things will happen if the mesh represented by the * input file does in fact have them. This * is due to the fact that most mesh description formats do not store * neighborship information between cells, so the grid reading functions have @@ -53,13 +54,19 @@ struct SubCellData; * common (complete) face, so the grid reader concludes that the adjacent * cells have no neighbors along these faces and must therefore be at the * boundary. In effect, an internal crack of the domain is introduced this - * way. Since such cases are very hard to detect, the library does not make - * any attempt to abort on such situations, and you will get a triangulation - * that probably does not do what you want. A solution to this problem is the + * way. Since such cases are very hard to detect (how is GridIn supposed to + * decide whether a place where the faces of two small cells coincide with + * the face or a larger cell is in fact a hanging node associated with local + * refinement, or is indeed meant to be a crack in the domain?), the library + * does not make any attempt to catch such situations, and you will get a triangulation + * that probably does not do what you want. If your goal is to save and later + * read again a triangulation that has been adaptively refined, then this + * class is not your solution; rather take a look at the * PersistentTriangulation class. * - * Note: if you experience unexpected problems with the use of this - * class, be sure to read the documentation right until the end, and + * @note It is not uncommon to experience unexpected problems when reading + * generated meshes for the first time using this class. If this applies to + * you, be sure to read the documentation right until the end, and * also read the documentation of the GridReordering class. * * To read grid data, the triangulation to be fed with has to be empty.