Augment documentation some more.

git-svn-id: https://svn.dealii.org/trunk@27820 0785d39b-7218-0410-832d-ea1e28bc413d

diff --git a/deal.II/include/deal.II/base/utilities.h b/deal.II/include/deal.II/base/utilities.h
index 7093ff32f441a5b2bf89875defad0ade44837abd..657472427dfa4a63d16968444d7609c20f875581 100644 (file)
--- a/deal.II/include/deal.II/base/utilities.h
+++ b/deal.II/include/deal.II/base/utilities.h
@@ -177,6 +177,17 @@ namespace Utilities
    * you need to use separate random number facilities for separate
    * threads, rather than this global function. For example, the C++11
    * standard offers such objects, as does BOOST.
+   *
+   * @note Like the system function rand(), this function produces
+   * the same sequence of random numbers every time a program is
+   * started. This is an important property for debugging codes,
+   * but it makes it impossible to really verify statistics
+   * properties of a code. For rand(), you can call srand() to
+   * "seed" the random number generator to get different sequences
+   * of random numbers every time a program is called. However, this
+   * function does not allow seeding the random number generator.
+   * If you need this, as above, use one of the C++ or BOOST
+   * facilities.
    */
   double
   generate_normal_random_number (const double a,