Small doc update.

git-svn-id: https://svn.dealii.org/trunk@2342 0785d39b-7218-0410-832d-ea1e28bc413d

diff --git a/deal.II/lac/include/lac/sparse_matrix.templates.h b/deal.II/lac/include/lac/sparse_matrix.templates.h
index 803f39efce7da515b01501c69df6ec76bf83ee35..b7364fe005e6d7ee9e388bd45d224cae42d31e2d 100644 (file)
--- a/deal.II/lac/include/lac/sparse_matrix.templates.h
+++ b/deal.II/lac/include/lac/sparse_matrix.templates.h
@@ -689,7 +689,8 @@ SparseMatrix<number>::precondition_SSOR (Vector<somenumber>& dst,
   const unsigned int  n            = src.size();
   const unsigned int *rowstart_ptr = &cols->rowstart[0];
   somenumber         *dst_ptr      = &dst(0);
-  
+
+                                  // forward sweep
   for (unsigned int row=0; row<n; ++row, ++dst_ptr, ++rowstart_ptr)
     {
       *dst_ptr = src(row);
@@ -708,6 +709,8 @@ SparseMatrix<number>::precondition_SSOR (Vector<somenumber>& dst,
                                       
       for (unsigned int j=(*rowstart_ptr)+1; j<first_right_of_diagonal_index; ++j)
        *dst_ptr -= om* val[j] * dst(cols->colnums[j]);
+
+                                      // divide by diagonal element
       *dst_ptr /= val[*rowstart_ptr];
     };
   
@@ -716,6 +719,7 @@ SparseMatrix<number>::precondition_SSOR (Vector<somenumber>& dst,
   for (unsigned int row=0; row<n; ++row, ++rowstart_ptr, ++dst_ptr)
     *dst_ptr *= (2.-om)*val[*rowstart_ptr];
 
+                                  // backward sweep
   rowstart_ptr = &cols->rowstart[n-1];
   dst_ptr      = &dst(n-1);
   for (int row=n-1; row>=0; --row, --rowstart_ptr, --dst_ptr)