tests: Add test-advection-diffusion.cpp.

This provides a unit test for the errors of the vanilla SDC algorithm.

Signed-off-by: Matthew Emmett <[email protected]>

Author: memmett

examples/advection_diffusion/advection_diffusion_sweeper.hpp

@@ -102,6 +102,11 @@ class AdvectionDiffusionSweeper
 		    (pair<size_t, size_t>(n, k), max));
     }
 
+    auto get_errors()
+    {
+      return errors;
+    }
+
     void predict(bool initial)
     {
       pfasst::encap::IMEXSweeper<time>::predict(initial);

examples/advection_diffusion/vanilla_sdc.cpp

@@ -14,7 +14,7 @@
 
 #include "advection_diffusion_sweeper.hpp"
 
-int main(int argc, char** argv)
+auto run_vanilla_sdc()
 {
   pfasst::SDC<> sdc;
 
@@ -41,4 +41,14 @@ int main(int argc, char** argv)
   sdc.run();
 
   fftw_cleanup();
+
+  return sweeper->get_errors();
+}
+
+
+#ifndef PFASST_UNIT_TESTING
+int main(int argc, char** argv)
+{
+  run_vanilla_sdc();
 }
+#endif

tests/test-advection-diffusion.cpp

@@ -0,0 +1,57 @@
+/*
+ * Tests for the advection-diffusion examples.
+ */
+
+#include <algorithm>
+#include <iostream>
+#include <tuple>
+#include <vector>
+
+#include <gtest/gtest.h>
+#include <gmock/gmock.h>
+
+#define PFASST_UNIT_TESTING
+#include "../examples/advection_diffusion/vanilla_sdc.cpp"
+#undef PFASST_UNIT_TESTING
+
+using namespace std;
+
+
+MATCHER(DoubleNear, "")
+{
+  return abs(get<0>(arg) - get<1>(arg)) < 1e-15;
+}
+
+MATCHER(DoubleLess, "")
+{
+  return get<0>(arg) < get<1>(arg);
+}
+
+TEST(ErrorTest, VanillaSDC)
+{
+  typedef pair<pair<size_t, size_t>, double> vtype;
+
+  auto errors = run_vanilla_sdc();
+  auto get_iter  = [](const vtype x) { return get<1>(get<0>(x)); };
+  auto get_step  = [](const vtype x) { return get<0>(get<0>(x)); };
+  auto get_error = [](const vtype x) { return get<1>(x); };
+
+  auto max_iter = get_iter(*std::max_element(errors.begin(), errors.end(),
+             [get_iter](const vtype p1, const vtype p2) { return get_iter(p1) < get_iter(p2); }));
+
+  vector<double> tol = { 7e-9, 7e-9, 7e-9, 7e-9 };
+  vector<double> err;
+  for (auto& x: errors) {
+    if (get_iter(x) == max_iter) {
+      err.push_back(get_error(x));
+    }
+  }
+
+  EXPECT_THAT(err, testing::Pointwise(DoubleLess(), tol));
+}
+
+int main(int argc, char** argv)
+{
+  testing::InitGoogleTest(&argc, argv);
+  return RUN_ALL_TESTS();
+}