add function documentation

git-svn-id: https://svn.dealii.org/trunk@15101 0785d39b-7218-0410-832d-ea1e28bc413d

diff --git a/deal.II/base/include/base/flow_function.h b/deal.II/base/include/base/flow_function.h
index 2bdde879b20ec56d1060ce48da3de9da555ca5ef..da682e0418411003dbc9ac5cff4da33640866887 100644 (file)
--- a/deal.II/base/include/base/flow_function.h
+++ b/deal.II/base/include/base/flow_function.h
@@ -172,6 +172,12 @@ namespace Functions
  * Artificial divergence free function with homogeneous boundary
  * conditions on the cube [-1,1]<sup>dim</sup>.
  *
+ * The function in 2D is
+ * @f[
+ * \left(\begin{array}{c}u\\v\\p\end{array}\right)
+ * \left(\begin{array}{c}\cos^2x \sin y\cos y\\-\sin x\cos x\cos^2y\\
+ * \sin x\cos x\sin y\cos y\end{array}\right)
+ * @f]
  * @ingroup functions
  * @author Guido Kanschat, 2007
  */