test_RandomNumbers_SFMT_Uniform.cpp

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#ifdef USE_SFMTLIB

#include "test.h"

#include "randomNumbers_SFMT.h"

//====================================================================

namespace Test_RandomNumbers_SFMT {
  const std::string test_name = "RandomNumbers.SFMT.Uniform";

  //- test-private parameters
  namespace {
    const std::string filename_input  = "test_RandomNumbers_SFMT_Uniform.yaml";
    const std::string filename_output = "stdout";

    class Parameters_Test_RandomNumbers : public Parameters {
     public:
      Parameters_Test_RandomNumbers()
      {
        Register_int("number_of_seeds", 0);
        Register_int("seed_base", 0);
        Register_int("number_of_samples", 0);

        Register_string("verbose_level", "NULL");

        Register_double("expected_result", 0.0);
      }
    };
  }

  //- prototype declaration
  int uniform_calc_pi(void);

#ifdef USE_TESTMANAGER_AUTOREGISTER
  namespace {
    static const bool is_registered = TestManager::RegisterTest(
      test_name,
      uniform_calc_pi
      );
  }
#endif

  //====================================================================
  int uniform_calc_pi(void)
  {
    // ####  parameter setup  ####
    unique_ptr<Parameters> params_test(new Parameters_Test_RandomNumbers);
    unique_ptr<Parameters> params_all(new Parameters);

    params_all->Register_Parameters("Test_RandomNumbers", params_test);

    ParameterManager::read(filename_input, params_all);

    int          Nseed      = params_test->get_int("number_of_seeds");
    int          seed_base  = params_test->get_int("seed_base");
    int          Nrand      = params_test->get_int("number_of_samples");
    const string str_vlevel = params_test->get_string("verbose_level");

    const bool   do_check        = params_test->is_set("expected_result");
    const double expected_result = do_check ? params_test->get_double("expected_result") : 0.0;

    Bridge::VerboseLevel vl = vout.set_verbose_level(str_vlevel);

    //- print input parameters
    vout.general(vl, "  Nseed     = %d\n", Nseed);
    vout.general(vl, "  seed_base = %d\n", seed_base);
    vout.general(vl, "  Nrand     = %d\n", Nrand);
    vout.general(vl, "  vlevel    = %s\n", str_vlevel.c_str());
    vout.general(vl, "\n");


    // #### object setup #####
    unique_ptr<Timer> timer(new Timer(test_name));


    // ####  Execution main part  ####
    timer->start();

    vout.general(vl, "\n");
    vout.general(vl, "Monte Carlo estimate of pi:\n");
    vout.general(vl, "  number of samples = %10d\n", Nrand);
    vout.general(vl, "        seed    estimate of pi\n");

    double t1 = 0.0;
    double t2 = 0.0;
    for (int iseed = 0; iseed < Nseed; ++iseed) {
      int iseed2 = seed_base + iseed;

      unique_ptr<RandomNumbers> rand(new RandomNumbers_SFMT(iseed2));

      int Npi = 0;
      for (int i = 0; i < Nrand; ++i) {
        double rand1 = rand->get();
        double rand2 = rand->get();
        double r     = rand1 * rand1 + rand2 * rand2;
        if (r < 1.0) { ++Npi;  }
        //  vout.general(vl, "  %10.8f  %10.8f\n",rand1,rand2);
      }

      double pi_exp = (4.0 * Npi) / Nrand;

      t1 += pi_exp;
      t2 += pi_exp * pi_exp;

      //vout.general(vl, "  estimate of pi    = %10.8f\n",pi_exp);
      vout.general(vl, "  %10d    %14.10f\n", iseed2, pi_exp);
    }

    double api = t1 / (double)Nseed;
    double vpi = t2 / (double)Nseed - api * api;
    double dpi = sqrt(vpi);
    double epi = dpi / sqrt((double)Nseed - 1);

    double pi = 3.141592653589793;
    vout.general(vl, "  true value = %10.8f\n", pi);
    vout.general(vl, "  average    = %10.8f\n", api);
    vout.general(vl, "  variance   = %10.8f\n", vpi);
    vout.general(vl, "  deviation  = %10.8f\n", dpi);
    vout.general(vl, "  error      = %10.8f\n", epi);

    double result = api;
    // changed to check the obtained value of pi itseft. [25 May 2014 H.M.]

    timer->report();


    if (do_check) {
      return Test::verify(result, expected_result);
    } else {
      vout.detailed(vl, "check skipped: expected_result not set.\n\n");
      return EXIT_SKIP;
    }
  }
} // namespace Test_RandomNumbers
#endif  // USE_SFMTLIB