FastAndPoorGauss_test.cc File Reference

Unit test for util::FastAndPoorGauss. More...

#include <boost/test/unit_test.hpp>
#include <boost/test/tools/floating_point_comparison.hpp>
#include "icarusalg/Utilities/FastAndPoorGauss.h"
#include "larcorealg/CoreUtils/counter.h"
#include "TFile.h"
#include "TH1F.h"
#include "TF1.h"
#include "TFitResult.h"

Go to the source code of this file.

Macros
#define	BOOST_TEST_MODULE   FastAndPoorGauss

Functions
template<std::size_t NSamples>
void	Test (TFile *pFile=nullptr, bool statChecks=true)
	BOOST_AUTO_TEST_CASE (TestCase)

Detailed Description

Unit test for util::FastAndPoorGauss.

Date

February 15, 2020

Author

Gianluca Petrillo (petri.nosp@m.llo@.nosp@m.slac..nosp@m.stan.nosp@m.ford..nosp@m.edu)

See Also

`icarusalg/Utilities/FastAndPoorGauss.h

Definition in file FastAndPoorGauss_test.cc.

Macro Definition Documentation

#define BOOST_TEST_MODULE   FastAndPoorGauss

Definition at line 10 of file FastAndPoorGauss_test.cc.

Function Documentation

BOOST_AUTO_TEST_CASE

(

TestCase

)

Definition at line 74 of file FastAndPoorGauss_test.cc.

                                 {
  
  TFile F("FastAndPoorGauss_test.root", "RECREATE");
  
  Test<   1024U>(&F, false); // with low points the statistics is not very good;
  Test<   4096U>(&F, false); // so we skip the statistics checks
  Test<   8192U>(&F, false);
  Test<  16384U>(&F);
  Test<  32768U>(&F);
  Test<  65536U>(&F);
  Test< 131072U>(&F);
  Test< 262144U>(&F);
  Test< 524288U>(&F);
//   Test<1048576U>(&F);
  
  F.Write();
  
} // BOOST_AUTO_TEST_CASE( TestCase )

template<std::size_t NSamples>

void Test	(	TFile *	pFile = nullptr,
		bool	statChecks = true
	)

Definition at line 30 of file FastAndPoorGauss_test.cc.

                                                          {
  
  constexpr unsigned int NPoints = 1'000'000U;
  
  std::string const NSamplesTag = std::to_string(NSamples);
  
  util::FastAndPoorGauss<NSamples> gauss;
  BOOST_TEST_MESSAGE("Testing sampling " << NSamples << " points.");
  
  TH1D HGaus(
    ("HGaus" + NSamplesTag).c_str(),
    ("Distribution from util::FastAndPoorGauss<" + NSamplesTag + ">").c_str(),
    1024, -5.0, +5.0
    );
  HGaus.SetDirectory(pFile);
  
  util::UniformSequence<> extract { NPoints };
  for (auto _ [[gnu::unused]]: util::counter(NPoints)) {
    double const u = extract();
    double const z = gauss(u);
    HGaus.Fill(z);
  } // for
  
  TF1* pGaus = new TF1(("FGaus" + NSamplesTag).c_str(), "gaus", -5.0, +5.0);
  TFitResultPtr pFitRes = HGaus.Fit(pGaus, "QS"); // Quiet, reSult
  BOOST_CHECK(pFitRes->IsValid());
  if (statChecks) BOOST_CHECK_LT(pFitRes->Chi2()/pFitRes->Ndf(), 5.0);
  pFitRes->Print();
  
  // mean should be smaller than twice its uncertainty
  if (statChecks) BOOST_CHECK_SMALL(pFitRes->Parameter(1), 2.*pFitRes->Error(1));
  if (statChecks) BOOST_CHECK_CLOSE(pFitRes->Parameter(2), 1.0, 1.0); // stddev (1% tolerance)
  
  if (pFile) {
    HGaus.Write();
    HGaus.SetDirectory(nullptr);
  }
  
} // void Test()