NuclearComposition.hpp

/*
 * (c) Copyright 2020 CORSIKA Project, corsika-project@lists.kit.edu
 *
 * This software is distributed under the terms of the GNU General Public
 * Licence version 3 (GPL Version 3). See file LICENSE for a full version of
 * the license.
 */

#pragma once

#include <corsika/framework/core/ParticleProperties.hpp>
#include <corsika/framework/core/PhysicalUnits.hpp>

#include <cassert>
#include <functional>
#include <numeric>
#include <random>
#include <stdexcept>
#include <vector>

namespace corsika {

  class NuclearComposition {
  public:
    NuclearComposition(std::vector<Code> const& pComponents,
                       std::vector<double> const& pFractions);

    template <typename TFunction>
    auto getWeighted(TFunction func) const;

    template <typename TFunction>
    auto getWeightedSum(TFunction func) const -> decltype(func(std::declval<Code>()));

    size_t getSize() const;

    std::vector<double> const& getFractions() const;
    std::vector<Code> const& getComponents() const;
    double const getAverageMassNumber() const;

    template <class TRNG>
    Code sampleTarget(std::vector<CrossSectionType> const& sigma,
                      TRNG&& randomStream) const;

    // Note: when this class ever modifies its internal data, the hash
    // must be updated, too!
    size_t getHash() const;

    bool operator==(NuclearComposition const& v) const;

  private:
    void updateHash();

    std::vector<double> const numberFractions_; 
    std::vector<Code> const components_;        

    double const avgMassNumber_;

    std::size_t hash_;
  };

} // namespace corsika

#include <corsika/detail/media/NuclearComposition.inl>