Doc update.

git-svn-id: https://svn.dealii.org/trunk@8896 0785d39b-7218-0410-832d-ea1e28bc413d

diff --git a/deal.II/lac/include/lac/sparsity_pattern.h b/deal.II/lac/include/lac/sparsity_pattern.h
index f42655f7ab58314e8bfd87631ef9205b7f5f5d6a..611df8f8c8021c8a2d819cd77e0587a531b45e3a 100644 (file)
--- a/deal.II/lac/include/lac/sparsity_pattern.h
+++ b/deal.II/lac/include/lac/sparsity_pattern.h
@@ -73,6 +73,13 @@ namespace internals
                                           * Column number of the
                                           * element represented by
                                           * this object.
+                                          *
+                                          * Note that if the underlying
+                                          * sparsity pattern has not yet been
+                                          * compressed, then this function may
+                                          * return @p
+                                          * SparsityPattern::invalid_index for
+                                          * certain elements of the matrix.
                                           */
         unsigned int column() const;