MultivariateGaussianComptonProfile.h

Go to the documentation of this file.

// Mantid Repository : https://github.com/mantidproject/mantid
//
// Copyright © 2013 ISIS Rutherford Appleton Laboratory UKRI,
//   NScD Oak Ridge National Laboratory, European Spallation Source,
//   Institut Laue - Langevin & CSNS, Institute of High Energy Physics, CAS
// SPDX - License - Identifier: GPL - 3.0 +
#pragma once
 
#include <cmath>
 
#include "MantidCurveFitting/DllConfig.h"
#include "MantidCurveFitting/Functions/ComptonProfile.h"
 
namespace Mantid {
namespace CurveFitting {
namespace Functions {
 
class MANTID_CURVEFITTING_DLL MultivariateGaussianComptonProfile : public ComptonProfile {
public:
  static const char *AMP_PARAM;
  static const char *SIGMA_X_PARAM;
  static const char *SIGMA_Y_PARAM;
  static const char *SIGMA_Z_PARAM;
  static const char *STEPS_ATTR;
 
  MultivariateGaussianComptonProfile();
 
  void buildS2Cache(std::vector<double> &s2Cache) const;
 
private:
  std::string name() const override;
  void declareParameters() override;
  void declareAttributes() override;
  void setAttribute(const std::string &name, const Attribute &value) override;
 
  std::vector<size_t> intensityParameterIndices() const override;
  size_t fillConstraintMatrix(Kernel::DblMatrix &cmatrix, const size_t start,
                              const HistogramData::HistogramE &errors) const override;
 
  void massProfile(double *result, const size_t nData) const override;
 
  void massProfile(double *result, const size_t nData, const double amplitude) const;
 
  double calculateJ(std::vector<double> s2Cache, double y) const;
  double calculateFSE(std::vector<double> s2Cache, double y) const;
 
  inline double calculateIntegrandJ(double s2, double y) const { return s2 * exp(-(y * y) / (2.0 * s2)); }
 
  inline double calculateIntegrandFSE(double s2, double y) const {
    return ((pow(y, 3) / pow(s2, 4)) - ((3 * y) / pow(s2, 2))) * exp(-(y * y) / (2.0 * s2));
  }
 
  double intervalCoeff(int i, int j) const;
 
  int m_integrationSteps; 
  double m_thetaStep;     
  double m_phiStep;       
};
 
} // namespace Functions
} // namespace CurveFitting
} // namespace Mantid