Doc update.

git-svn-id: https://svn.dealii.org/trunk@349 0785d39b-7218-0410-832d-ea1e28bc413d

diff --git a/deal.II/deal.II/include/numerics/assembler.h b/deal.II/deal.II/include/numerics/assembler.h
index 6f7a7e2fd622b3f997a0b79a2fc625e4963736e2..a764d53ed4846c9e35fbd9e7fc221042a94051a4 100644 (file)
--- a/deal.II/deal.II/include/numerics/assembler.h
+++ b/deal.II/deal.II/include/numerics/assembler.h
@@ -43,6 +43,15 @@ class Equation {
                                      * Virtual function which assembles the
                                      * cell matrix and the right hand side
                                      * on a given cell.
+                                     *
+                                     * This function assumes the cell matrix
+                                     * and right hand side to have the right
+                                     * size and to be empty. Functions of
+                                     * derived classes should check for
+                                     * this.
+                                     * For that purpose, the two exceptions
+                                     * #ExcWrongSize# and #ExcObjectNotEmpty#
+                                     * are declared.
                                      */
     virtual void assemble (dFMatrix            &cell_matrix,
                           dVector             &rhs,
@@ -52,6 +61,15 @@ class Equation {
                                     /**
                                      * Virtual function which only assembles
                                      * the cell matrix on a given cell.
+                                     *
+                                     * This function assumes the cell matrix
+                                     * and right hand side to have the right
+                                     * size and to be empty. Functions of
+                                     * derived classes should check for
+                                     * this.
+                                     * For that purpose, the two exceptions
+                                     * #ExcWrongSize# and #ExcObjectNotEmpty#
+                                     * are declared.
                                      */
     virtual void assemble (dFMatrix            &cell_matrix,
                           const FEValues<dim> &fe_values,
@@ -60,6 +78,15 @@ class Equation {
                                     /**
                                      * Virtual function which only assembles
                                      * the right hand side on a given cell.
+                                     *
+                                     * This function assumes the cell matrix
+                                     * and right hand side to have the right
+                                     * size and to be empty. Functions of
+                                     * derived classes should check for
+                                     * this.
+                                     * For that purpose, the two exceptions
+                                     * #ExcWrongSize# and #ExcObjectNotEmpty#
+                                     * are declared.
                                      */
     virtual void assemble (dVector             &rhs,
                           const FEValues<dim> &fe_values,
@@ -76,6 +103,17 @@ class Equation {
                                      * Exception
                                      */
     DeclException0 (ExcPureVirtualFunctionCalled);
+                                    /**
+                                     * Exception
+                                     */
+    DeclException2 (ExcWrongSize,
+                   int, int,
+                   << "Object has wrong size " << arg1
+                   << ", but should have " << arg2 << ".");
+                                    /**
+                                     * Exception
+                                     */
+    DeclException0 (ExcObjectNotEmpty);
     
   protected:
                                     /**
@@ -126,13 +164,19 @@ struct AssemblerData {
 
                                     /**
                                      * Pointer to the matrix to be assembled
-                                     * by this object.
+                                     * by this object. Elements are summed
+                                     * up by the assembler, so you may want
+                                     * to clear this object (set all entries
+                                     * to zero) before use.
                                      */
     dSMatrix               &matrix;
 
                                     /**
                                      * Pointer to the vector to be assembled
-                                     * by this object.
+                                     * by this object. Elements are summed
+                                     * up by the assembler, so you may want
+                                     * to clear this object (set all entries
+                                     * to zero) before use.
                                      */
     dVector                &rhs_vector;
     
@@ -197,7 +241,12 @@ class Assembler : public DoFCellAccessor<dim> {
     
                                     /**
                                      * Assemble on the present cell using
-                                     * the given equation object.
+                                     * the given equation objectand the data
+                                     * passed to the constructor. The elements
+                                     * of the local matrix and right hand side
+                                     * are added to the global matrix and
+                                     * vector so you may want to clear the
+                                     * matrix before use.
                                      */
     void assemble (const Equation<dim> &);