Fermion_Double_Index.h

#ifndef QNANO_NEW_FERMION_DOUBLE_INDEX_DEFINED_H
#define QNANO_NEW_FERMION_DOUBLE_INDEX_DEFINED_H

#include "manybody/Fermion_Index.h"
//#include "MPI_Distribute.h"


class Fermion_Double_Index {
public:
  //Main data: Fermion indices for electrons and holes, respectively:
  Fermion_Index fi_e;
  Fermion_Index fi_h;


  double sort_get_sign();

  //Constructors:
  Fermion_Double_Index() {}
  Fermion_Double_Index(const std::vector<int> & lst_e, const std::vector<int> & lst_h) \
    : fi_e(lst_e), fi_h(lst_h){
  }
  Fermion_Double_Index(const Fermion_Index & fi_e_,const Fermion_Index & fi_h_)\
    : fi_e(fi_e_), fi_h(fi_h_){
  }
  Fermion_Double_Index(size_t se, size_t sh)\
    : fi_e(se), fi_h(sh){
  }
  Fermion_Double_Index(const Fermion_Double_Index & other)\
    : fi_e(other.fi_e), fi_h(other.fi_h){
  }
  Fermion_Double_Index &operator=(const Fermion_Double_Index & other);

  //Compare operators for sorting and searching
  bool operator==(const Fermion_Double_Index &other) const;
  bool operator!=(const Fermion_Double_Index &other) const;
  bool operator<(const Fermion_Double_Index &other) const;
  bool operator>(const Fermion_Double_Index &other) const;
};
std::ostream &operator<<(std::ostream & os, const Fermion_Double_Index & fi);



//Construct all possible sets of Fermion_Double_Indices for a given number
// and rank of electrons and holes.
std::vector<Fermion_Double_Index> get_all_Fermion_Double_Indices(size_t rank_e, size_t nr_e, size_t rank_h, size_t nr_h, size_t start_e=0, size_t start_h=0);






bool sort_Fermion_Double_Index( const Fermion_Double_Index &i1 ,const Fermion_Double_Index &i2  );

bool sort_cv_Fermion_Double_Index( \
const std::pair<Fermion_Double_Index, std::complex<double> > &i1, \
const std::pair<Fermion_Double_Index, std::complex<double> > &i2 );


size_t Hash_Fermion_Double_Index(const Fermion_Double_Index &fi);



/*
void distribute_Fermion_Index(MPI_Comm comm, Fermion_Index & fi, int tag=0){
  size_t sz;
  int MPI_rank;
  MPI_Comm_rank(comm, &MPI_rank);
  if(MPI_rank==0)sz=fi.size();
  MPI_Distribute::distribute_size_t(comm, sz, tag);
  if(MPI_rank!=0)fi.resize(sz);
  for(size_t i=0; i<sz; i++){
    MPI_Distribute::distribute_size_t(comm, fi[i], tag);
  }
}

void distribute_Fermion_Double_Index(MPI_Comm comm, Fermion_Double_Index & fi, int tag=0){
  distribute_Fermion_Index(comm, fi.fi_e, tag);
  distribute_Fermion_Index(comm, fi.fi_h, tag);
}

void distribute_Fermion_Double_Index_vector(MPI_Comm comm, std::vector<Fermion_Double_Index> & v, int tag=0){
  size_t sz;
  int MPI_rank;
  MPI_Comm_rank(comm, &MPI_rank);
  if(MPI_rank==0)sz=v.size();
  MPI_Distribute::distribute_size_t(comm, sz, tag);
  if(MPI_rank!=0)v.resize(sz);
  for(size_t i=0; i<sz; i++){
    distribute_Fermion_Double_Index(comm, v[i], tag);
  }

}
*/


#endif