update documentation

diff --git a/include/deal.II/multigrid/mg_constrained_dofs.h b/include/deal.II/multigrid/mg_constrained_dofs.h
index 3dddfd03d88ac2677225e4665c11cce92fd77ed5..9f58071a3411ee50bc7ec76fa5bcc4554e95a36f 100644 (file)
--- a/include/deal.II/multigrid/mg_constrained_dofs.h
+++ b/include/deal.II/multigrid/mg_constrained_dofs.h
@@ -94,7 +94,10 @@ public:
   get_boundary_indices () const DEAL_II_DEPRECATED;
 
   /**
-   * Return the indices of dofs for each level that are subject to boundary constraints.
+   * Return the indices of level dofs on the given level that are subject to
+   * Dirichlet boundary conditions (as set by the @p function_map parameter in
+   * initialize()).  The indices are restricted to the set of locally relevant
+   * level dofs.
    */
   const IndexSet &
   get_boundary_indices (const unsigned int level) const;