real_polyhedral_homotopy_continuation/reference/include/system/start/user.hpp

// This file is part of Bertini 2.
//
// system/start/user.hpp is free software: you can redistribute it and/or modify
// it under the terms of the GNU General Public License as published by
// the Free Software Foundation, either version 3 of the License, or
//(at your option) any later version.
//
// system/start/user.hpp is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
// GNU General Public License for more details.
//
// You should have received a copy of the GNU General Public License
// along with system/start/user.hpp.  If not, see
// <http://www.gnu.org/licenses/>.
//
//  Copyright(C) 2015 - 2021 by Bertini2 Development Team
//
//  See <http://www.gnu.org/licenses/> for a copy of the license,
//  as well as COPYING.  Bertini2 is provided with permitted
//  additional terms in the b2/licenses/ directory.

// individual authors of this file include:
// silviana amethyst, university of wisconsin eau claire

/**
\file system/start/user.hpp

\brief Defines the User-defined start system type.

the user provided start system is merely their system, evaluated at the start
time.
*/

#pragma once

#include "common/config.hpp"
#include "system/start/utility.hpp"
#include "system/start_base.hpp"

// these next two blobs solve a problem of private-ness.
// see
// https://stackoverflow.com/questions/4112075/trouble-overriding-save-construct-data-when-serializing-a-pointer-to-a-class-wit

// forward declare the User start system
namespace bertini {
namespace start_system {
class User;
}
}  // namespace bertini

// forward declare the function, so we can friend it below.
namespace boost {
namespace serialization {
template <class Archive>
inline void save_construct_data(Archive& ar,
                                const bertini::start_system::User* t,
                                const unsigned int file_version);
}
}  // namespace boost
// end nonsense for friends.  so lonely, but c++ friends don't solve the irl
// problem at all.

namespace bertini {
namespace start_system {

/**
\brief The user-provided start system for Numerical Algebraic Geometry


*/
class User : public StartSystem {
 public:
  User() =
      delete;  // deleted because requires a reference to a System to construct
  virtual ~User() = default;

  /**
   Constructor for making a user-provided start system from another.
  */
  User(System const& s, SampCont<dbl> const& solns);
  User(System const& s, SampCont<mpfr_complex> const& solns);

  /**
  Get the number of start points for this start system.
  */
  unsigned long long NumStartPoints() const override;

  User& operator*=(Nd const& n) = delete;

  User& operator+=(System const& sys) = delete;

 private:
  /**
  Get the ith start point, in double precision.

  Called by the base StartSystem's StartPoint(index) method.
  */
  Vec<dbl> GenerateStartPoint(dbl, unsigned long long index) const override;

  /**
  Get the ith start point, in current default precision.

  Called by the base StartSystem's StartPoint(index) method.
  */
  Vec<mpfr_complex> GenerateStartPoint(mpfr_complex,
                                       unsigned long long index) const override;

  friend class boost::serialization::access;
  template <class Archive>
  friend void boost::serialization::save_construct_data(
      Archive& ar, const User* t, const unsigned int file_version);

  template <typename Archive>
  void serialize(Archive& ar, const unsigned version) {
    ar& boost::serialization::base_object<StartSystem>(*this);
  }

  const bertini::System& user_system_;
  std::tuple<SampCont<dbl>, SampCont<mpfr_complex>> solns_;
  bool solns_in_dbl_;
};
}  // namespace start_system
}  // namespace bertini

namespace boost {
namespace serialization {
template <class Archive>
inline void save_construct_data(Archive& ar,
                                const bertini::start_system::User* t,
                                const unsigned int file_version) {
  // save data required to construct instance
  ar << t->user_system_;
  ar << t->solns_in_dbl_;

  ar << std::get<0>(t->solns_);
  ar << std::get<1>(t->solns_);
}

template <class Archive>
inline void load_construct_data(Archive& ar, bertini::start_system::User* t,
                                const unsigned int file_version) {
  // retrieve data from archive required to construct new instance
  bertini::System sys;
  ar >> sys;

  bool solns_in_dbl;
  ar >> solns_in_dbl;

  if (solns_in_dbl) {
    bertini::SampCont<bertini::dbl> solns;
    ar >> solns;
    ::new (t) bertini::start_system::User(sys, solns);
  } else {
    bertini::SampCont<bertini::mpfr_complex> solns;
    ar >> solns;
    ::new (t) bertini::start_system::User(sys, solns);
  }
}
}  // namespace serialization
}  // namespace boost