Add test.

diff --git a/tests/base/generate_normal_random_number_01.cc b/tests/base/generate_normal_random_number_01.cc
new file mode 100644 (file)
index 0000000..f127452
--- /dev/null
+++ b/tests/base/generate_normal_random_number_01.cc
@@ -0,0 +1,87 @@
+// ---------------------------------------------------------------------
+//
+// Copyright (C) 2005 - 2015 by the deal.II authors
+//
+// This file is part of the deal.II library.
+//
+// The deal.II library is free software; you can use it, redistribute
+// it, and/or modify it under the terms of the GNU Lesser General
+// Public License as published by the Free Software Foundation; either
+// version 2.1 of the License, or (at your option) any later version.
+// The full text of the license can be found in the file LICENSE at
+// the top level of the deal.II distribution.
+//
+// ---------------------------------------------------------------------
+
+
+// test Utilities::generate_random_normal_number. this function is
+// supposed to be thread-safe, so check that a standard measure of
+// normality holds for the numbers produced on different threads
+
+#include "../tests.h"
+#include <iomanip>
+#include <iomanip>
+#include <fstream>
+#include <cmath>
+
+#include <deal.II/base/utilities.h>
+
+
+std::pair<double,double> test ()
+{
+  const double mu    = 13;
+  const double sigma = 3;
+  
+  unsigned int N = 1000000;
+  double sum        = 0;
+  double sum_square = 0;
+  for (unsigned int i=0; i<N; ++i)
+    {
+      const double x = Utilities::generate_normal_random_number (mu, sigma);
+
+      sum += x;
+      sum_square += x*x;
+    }
+
+  const double mean   = sum/N;
+  const double stddev = std::sqrt (sum_square/N - sum/N * sum/N);
+
+  return std::make_pair(mean, stddev);
+}
+
+
+
+
+int main()
+{
+  std::ofstream logfile("output");
+  deallog.attach(logfile);
+  deallog.depth_console(0);
+  deallog.threshold_double(1.e-10);
+
+  // create 4 threads, run the test function on them
+  Threads::Thread<std::pair<double,double> > tg[4];
+  tg[0] = Threads::new_thread (&test);
+  tg[1] = Threads::new_thread (&test);
+  tg[2] = Threads::new_thread (&test);
+  tg[3] = Threads::new_thread (&test);
+
+  tg[0].join();
+  tg[1].join();
+  tg[2].join();
+  tg[3].join();
+  
+  
+  // the random number generator is thread-local, so we should get the
+  // same result every time
+  deallog << tg[0].return_value().first
+         << ' '
+         << tg[0].return_value().second
+         << std::endl;
+  AssertThrow (tg[1].return_value() == tg[0].return_value(),
+              ExcInternalError());
+  AssertThrow (tg[2].return_value() == tg[0].return_value(),
+              ExcInternalError());
+  AssertThrow (tg[3].return_value() == tg[0].return_value(),
+              ExcInternalError());
+}

diff --git a/tests/base/generate_normal_random_number_01.output b/tests/base/generate_normal_random_number_01.output
new file mode 100644 (file)
index 0000000..d9c9002
--- /dev/null
+++ b/tests/base/generate_normal_random_number_01.output
@@ -0,0 +1,2 @@
+
+DEAL::12.9995 3.00072