From: bangerth <bangerth@0785d39b-7218-0410-832d-ea1e28bc413d>
Date: Mon, 17 Mar 2008 05:38:04 +0000 (+0000)
Subject: Add a note on the definition of (.,.)
X-Git-Url: https://gitweb.dealii.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=86a0befd6e7d19351f0b3119a447c6fe689670e7;p=dealii-svn.git

Add a note on the definition of (.,.)

git-svn-id: https://svn.dealii.org/trunk@15899 0785d39b-7218-0410-832d-ea1e28bc413d
---

diff --git a/deal.II/doc/doxygen/headers/vector_valued.h b/deal.II/doc/doxygen/headers/vector_valued.h
index 265e1e8dd5..d85fb20890 100644
--- a/deal.II/doc/doxygen/headers/vector_valued.h
+++ b/deal.II/doc/doxygen/headers/vector_valued.h
@@ -148,8 +148,13 @@
   -
   (q, \mathrm{div}\ \mathbf u)
   =
-  (q,f).
+  (q,f),
 @f}
+ * where we have defined the scalar product
+ * $(\mathbf v, \mathbf u) = \int_\Omega \mathbf v(x)
+ * \cdot \mathbf u(x) \; dx$, and similarly if both parts of the scalar
+ * product are scalar-valued functions (e.g. the pressure) rather
+ * than vector-valued onces (like the velocity).
  *
  * We get the final form by integrating by part the second term:
 @f{eqnarray*}