SphericalFitFunction.cc

Go to the documentation of this file.

#include "SphericalFitFunction.h"

#include <utl/PhysicalConstants.h>

#include <TMath.h>


using namespace utl;


namespace RdSphericalFit {

  double
  SphericalFitFunction::operator()(const std::vector<double>& pars)
    const
  {
    // store parameters in class
    UpdateParameters(pars);

    const utl::Vector source(fRadius, fTheta, fPhi, fLocalCS, utl::Vector::kSpherical);


    std::vector<double> expectedTimes;
    for (const auto& s : fStationData) {
      double expectedTime = (s.antennaPos - source).GetMag() / (fGamma * kSpeedOfLight);
      expectedTimes.push_back(expectedTime);
    }
    const double t0 = TMath::Mean(expectedTimes.begin(), expectedTimes.end());

    double chi2 = 0;
    for (unsigned int i=0; i<fStationData.size(); i++) {
      chi2 += pow(((fStationData[i].signalTime - ftmean) - (expectedTimes[i] - t0)) / fStationData[i].signalTimeErr, 2);
    }

    return chi2;
  }

  int
  SphericalFitFunction::GetNDF()
  {
    // 1 additional degree of freedom lost by the choice of the absolute event time
    return fStationData.size() - GetNFreeParameters() - 1;
  }


  double
  SphericalFitFunction::GetChi2(const std::vector<double>& pars)
  {
    return this->operator()(pars);
  }

}