Fix typo in GridTools::collect_periodic_faces

diff --git a/include/deal.II/grid/grid_tools.h b/include/deal.II/grid/grid_tools.h
index 970819d4d97da13b11f51db659e57166e30993be..ec479f99578939602aeb7ff8915dff61613402cd 100644 (file)
--- a/include/deal.II/grid/grid_tools.h
+++ b/include/deal.II/grid/grid_tools.h
@@ -2796,9 +2796,9 @@ namespace GridTools
    *
    * Instead of defining a 'first' and 'second' boundary with the help of two
    * boundary_ids this function defines a 'left' boundary as all faces with
-   * local face index <code>2*dimension</code> and boundary indicator @p b_id
+   * local face index <code>2*direction</code> and boundary indicator @p b_id
    * and, similarly, a 'right' boundary consisting of all face with local face
-   * index <code>2*dimension+1</code> and boundary indicator @p b_id. Faces
+   * index <code>2*direction+1</code> and boundary indicator @p b_id. Faces
    * with coordinates only differing in the @p direction component are
    * identified.
    *