]> https://gitweb.dealii.org/ - dealii-svn.git/commitdiff
Update documentation to mention a corner case that Seba found.
authorbangerth <bangerth@0785d39b-7218-0410-832d-ea1e28bc413d>
Thu, 28 Oct 2010 23:53:11 +0000 (23:53 +0000)
committerbangerth <bangerth@0785d39b-7218-0410-832d-ea1e28bc413d>
Thu, 28 Oct 2010 23:53:11 +0000 (23:53 +0000)
git-svn-id: https://svn.dealii.org/trunk@22544 0785d39b-7218-0410-832d-ea1e28bc413d

deal.II/include/deal.II/numerics/data_out.h

index c0e627abbd30ad9e1013e23a2867946877c572ec..0cd4978a329c8a803500b42c957a102e17026427 100644 (file)
@@ -122,7 +122,7 @@ namespace internal
        const dealii::hp::QCollection<dim> q_collection;
        const dealii::hp::MappingCollection<dim,spacedim> mapping_collection;
        dealii::hp::FEValues<dim,spacedim> x_fe_values;
-       
+
        std::vector<Point<spacedim> > patch_evaluation_points;
 
        const std::vector<std::vector<unsigned int> > *cell_to_patch_index_map;
@@ -377,26 +377,39 @@ class DataOut_DoFData : public DataOutInterface<patch_dim,patch_space_dim>
                                      * and of cells is usually not
                                      * equal, the function can
                                      * determine itself which type of
-                                     * vector it is given; however,
-                                     * there is one corner case,
-                                     * namely if you compute with
-                                     * piecewise constant elements
-                                     * and have one scalar quantity,
-                                     * then there are as many cells
-                                     * as there are degrees of
-                                     * freedom, but they may be
-                                     * ordered differently. In that
-                                     * case, you can change the last
-                                     * argument of the function from
-                                     * its default value
-                                     * #type_automatic to either
-                                     * #type_dof_data or #type_cell_data,
-                                     * depending on what the vector
-                                     * represents. Apart from this
-                                     * corner case, you can leave the
-                                     * argument at its default value
-                                     * and let the function determine
-                                     * the type of the vector itself.
+                                     * vector it is given. However,
+                                     * there are corner cases where
+                                     * this automatic determination
+                                     * does not work.  One example is
+                                     * if you compute with piecewise
+                                     * constant elements and have a
+                                     * scalar solution, then there
+                                     * are as many cells as there are
+                                     * degrees of freedom (though
+                                     * they may be numbered
+                                     * differently). Another
+                                     * possibility is if you have a
+                                     * 1d mesh embedded in 2d space
+                                     * and the mesh consists of a
+                                     * closed curve of cells; in this
+                                     * case, there are as many nodes
+                                     * as there are cells, and when
+                                     * using a Q1 element you will
+                                     * have as many degrees of
+                                     * freedom as there are cells.
+                                     * In these cases, you can change
+                                     * the last argument of the
+                                     * function from its default
+                                     * value #type_automatic to
+                                     * either #type_dof_data or
+                                     * #type_cell_data, depending on
+                                     * what the vector
+                                     * represents. Apart from such
+                                     * corner cases, you can leave
+                                     * the argument at its default
+                                     * value and let the function
+                                     * determine the type of the
+                                     * vector itself.
                                      *
                                      * If it is a vector holding DoF
                                      * data, the names given shall be

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