Bond.hpp

Go to the documentation of this file.

#ifndef CYTNX_BOND_H_
#define CYTNX_BOND_H_
 
#include "Type.hpp"
#include "cytnx_error.hpp"
#include "Symmetry.hpp"
#include <initializer_list>
#include <vector>
#include <fstream>
#include <map>
#include <algorithm>
#include "intrusive_ptr_base.hpp"
#include "utils/vec_clone.hpp"
 
namespace cytnx {
 
  enum bondType : int {
    BD_KET = -1, 
    BD_BRA = 1, 
    BD_REG = 0, 
    BD_NONE = 0, 
    BD_IN = -1, 
    BD_OUT = 1 
  };
 
  class Bond_impl : public intrusive_ptr_base<Bond_impl> {
   private:
   public:
    friend class Bond;
    cytnx_uint64 _dim;
    bondType _type;
    std::vector<cytnx_uint64> _degs;  // this only works for Qnum
    /*
        [Note], _degs has size only when the Bond is defined with Qnum, deg !!
                Use this size to check if the bond is type-2 (new type)
    */
    std::vector<std::vector<cytnx_int64>> _qnums;  //(dim, # of sym)
    std::vector<Symmetry> _syms;
 
    Bond_impl() : _dim(0), _type(bondType::BD_REG){};
 
    void _rm_qnum(const cytnx_uint64 &q_index) {
      // this will not check, so check it before using this internal function!!
      this->_dim -= this->_degs[q_index];
      this->_degs.erase(this->_degs.begin() + q_index);
      this->_qnums.erase(this->_qnums.begin() + q_index);
    }
 
    void Init(const cytnx_uint64 &dim, const bondType &bd_type = bondType::BD_REG);
 
    // new added
    void Init(const bondType &bd_type, const std::vector<std::vector<cytnx_int64>> &in_qnums,
              const std::vector<cytnx_uint64> &degs, const std::vector<Symmetry> &in_syms = {});
 
    bondType type() const { return this->_type; };
    const std::vector<std::vector<cytnx_int64>> &qnums() const { return this->_qnums; }
    std::vector<std::vector<cytnx_int64>> &qnums() { return this->_qnums; }
    const cytnx_uint64 &dim() const { return this->_dim; }
    cytnx_uint32 Nsym() const { return this->_syms.size(); }
    const std::vector<Symmetry> &syms() const { return this->_syms; }
    std::vector<Symmetry> &syms() { return this->_syms; }
 
    // this is clone return.
    std::vector<std::vector<cytnx_int64>> qnums_clone() const { return this->_qnums; }
    std::vector<Symmetry> syms_clone() const { return vec_clone(this->_syms); }
 
    bool has_duplicate_qnums() const {
      if (this->_degs.size()) {
        auto tmp = this->_qnums;
        std::sort(tmp.begin(), tmp.end());
        return std::adjacent_find(tmp.begin(), tmp.end()) != tmp.end();
      } else {
        return false;
      }
    }
 
    void set_type(const bondType &new_bondType) {
      if ((this->_type != BD_REG)) {
        if (new_bondType == BD_REG) {
          cytnx_error_msg(this->_qnums.size(),
                          "[ERROR] Cannot change type to BD_REG for a symmetry bond.%s", "\n");
        }
        if (std::abs(int(this->_type)) != std::abs(int(new_bondType))) {
          cytnx_error_msg(this->_qnums.size(),
                          "[ERROR] Cannot exchange BDtype between BD_* <-> gBD_* .%s", "\n");
        }
      }
 
      this->_type = new_bondType;
    }
 
    void clear_type() {
      if (this->_type != BD_REG) {
        cytnx_error_msg(this->_qnums.size(), "[ERROR] Cannot clear type for a symmetry bond.%s",
                        "\n");
      }
      this->_type = bondType::BD_REG;
    }
 
    boost::intrusive_ptr<Bond_impl> clone() const {
      boost::intrusive_ptr<Bond_impl> out(new Bond_impl());
      out->_dim = this->dim();
      out->_type = this->type();
      out->_qnums = this->qnums_clone();
      out->_syms = this->syms_clone();  // return a clone of vec!
      out->_degs = this->_degs;
      return out;
    }
 
    // [NOTE] for UniTensor internal, we might need to return the QNpool (unordered map for further
    // info on block arrangement!)
    void combineBond_(const boost::intrusive_ptr<Bond_impl> &bd_in, const bool &is_grp = true);
 
    boost::intrusive_ptr<Bond_impl> combineBond(const boost::intrusive_ptr<Bond_impl> &bd_in,
                                                const bool &is_grp = true) {
      boost::intrusive_ptr<Bond_impl> out = this->clone();
      out->combineBond_(bd_in, is_grp);
      return out;
    }
 
    // return a sorted qnums by removing all duplicates, sorted from large to small.
    std::vector<std::vector<cytnx_int64>> getUniqueQnums(std::vector<cytnx_uint64> &counts,
                                                         const bool &return_counts);
    // checked [KHW] ^^
    // return the degeneracy of the specify qnum set.
    cytnx_uint64 getDegeneracy(const std::vector<cytnx_int64> &qnum, const bool &return_indices,
                               std::vector<cytnx_uint64> &indices);
 
    // return the effective qnums when Bra-Ket mismatch.
    std::vector<std::vector<cytnx_int64>> calc_reverse_qnums();
 
    std::vector<cytnx_uint64> &getDegeneracies() { return this->_degs; };
    const std::vector<cytnx_uint64> &getDegeneracies() const { return this->_degs; };
 
    fermionParity get_fermion_parity(const std::vector<cytnx_int64> &qnum);
 
    std::vector<cytnx_uint64> group_duplicates_();
 
    boost::intrusive_ptr<Bond_impl> group_duplicates(std::vector<cytnx_uint64> &mapper) const {
      boost::intrusive_ptr<Bond_impl> out = this->clone();
      mapper = out->group_duplicates_();
      return out;
    }
 
    void force_combineBond_(const boost::intrusive_ptr<Bond_impl> &bd_in, const bool &is_grp);
 
  };  // Bond_impl
 
  class Bond {
   public:
    boost::intrusive_ptr<Bond_impl> _impl;
    Bond() : _impl(new Bond_impl()){};
    Bond(const Bond &rhs) { this->_impl = rhs._impl; }
    Bond &operator=(const Bond &rhs) {
      this->_impl = rhs._impl;
      return *this;
    }
 
    Bond(const cytnx_uint64 &dim, const bondType &bd_type = bondType::BD_REG)
        : _impl(new Bond_impl()) {
      this->_impl->Init(dim, bd_type);
    }
 
    Bond(const bondType &bd_type, const std::vector<std::vector<cytnx_int64>> &in_qnums,
         const std::vector<cytnx_uint64> &degs, const std::vector<Symmetry> &in_syms = {})
        : _impl(new Bond_impl()) {
      this->_impl->Init(bd_type, in_qnums, degs, in_syms);
    }
 
    Bond(const bondType &bd_type, const std::initializer_list<std::vector<cytnx_int64>> &in_qnums,
         const std::vector<cytnx_uint64> &degs, const std::vector<Symmetry> &in_syms = {})
        : _impl(new Bond_impl()) {
      this->_impl->Init(bd_type, in_qnums, degs, in_syms);
    }
 
    // this is needed for python binding!
    Bond(const bondType &bd_type, const std::vector<cytnx::Qs> &in_qnums,
         const std::vector<cytnx_uint64> &degs, const std::vector<Symmetry> &in_syms = {})
        : _impl(new Bond_impl()) {
      vec2d<cytnx_int64> qnums(in_qnums.begin(), in_qnums.end());
      this->_impl->Init(bd_type, qnums, degs, in_syms);
    }
 
    Bond(const bondType &bd_type,
         const std::vector<std::pair<std::vector<cytnx_int64>, cytnx_uint64>> &in_qnums_dims,
         const std::vector<Symmetry> &in_syms = {})
        : _impl(new Bond_impl()) {
      this->Init(bd_type, in_qnums_dims, in_syms);
    }
 
    void Init(const cytnx_uint64 &dim, const bondType &bd_type = bondType::BD_REG) {
      this->_impl->Init(dim, bd_type);
    }
 
    void Init(const bondType &bd_type, const std::vector<std::vector<cytnx_int64>> &in_qnums,
              const std::vector<cytnx_uint64> &degs, const std::vector<Symmetry> &in_syms = {}) {
      this->_impl->Init(bd_type, in_qnums, degs, in_syms);
    }
 
    void Init(const bondType &bd_type,
              const std::vector<std::pair<std::vector<cytnx_int64>, cytnx_uint64>> &in_qnums_dims,
              const std::vector<Symmetry> &in_syms = {}) {
      vec2d<cytnx_int64> qnums(in_qnums_dims.size());
      std::vector<cytnx_uint64> degs(in_qnums_dims.size());
      for (int i = 0; i < in_qnums_dims.size(); i++) {
        qnums[i] = in_qnums_dims[i].first;
        degs[i] = in_qnums_dims[i].second;
      }
      this->_impl->Init(bd_type, qnums, degs, in_syms);
    }
 
    bondType type() const { return this->_impl->type(); };
 
    const std::vector<std::vector<cytnx_int64>> &qnums() const { return this->_impl->qnums(); };
 
    std::vector<std::vector<cytnx_int64>> qnums_clone() const {
      return this->_impl->qnums_clone();
    };
 
    cytnx_uint64 dim() const { return this->_impl->dim(); };
 
    cytnx_uint32 Nsym() const { return this->_impl->syms().size(); };
 
    const std::vector<Symmetry> &syms() const { return this->_impl->syms(); };
 
    std::vector<Symmetry> syms_clone() const { return this->_impl->syms_clone(); };
 
    Bond retype(const bondType &new_bondType) const {
      Bond out = this->clone();
      out._impl->set_type(new_bondType);
      return out;
    }
 
    Bond redirect() const {
      Bond out = this->clone();
      out._impl->set_type(bondType(int(out.type()) * -1));
      return out;
    }
 
    Bond clone() const {
      Bond out;
      out._impl = this->_impl->clone();
      return out;
    }
 
    Bond combineBond(const Bond &bd_in, const bool &is_grp = true) const {
      Bond out;
      out._impl = this->_impl->combineBond(bd_in._impl, is_grp);
      return out;
    }
 
    Bond combineBond(const std::vector<Bond> &bds, const bool &is_grp = true) const {
      Bond out = this->clone();
      for (cytnx_uint64 i = 0; i < bds.size(); i++) {
        out._impl->combineBond_(bds[i]._impl, is_grp);
      }
      return out;
    }
 
    [[deprecated(
      "Please use "
      "Bond combineBond(const Bond &bd_in, const bool &is_grp) const "
      "instead.")]] Bond
      combineBonds(const std::vector<Bond> &bds, const bool &is_grp = true) const {
      Bond out = this->clone();
      for (cytnx_uint64 i = 0; i < bds.size(); i++) {
        out._impl->combineBond_(bds[i]._impl, is_grp);
      }
      return out;
    }
 
    std::vector<std::vector<cytnx_int64>> getUniqueQnums(std::vector<cytnx_uint64> &counts) {
      return this->_impl->getUniqueQnums(counts, true);
    }
 
    std::vector<std::vector<cytnx_int64>> getUniqueQnums() {
      std::vector<cytnx_uint64> tmp;
      return this->_impl->getUniqueQnums(tmp, false);
    }
 
    cytnx_uint64 getDegeneracy(const std::vector<cytnx_int64> &qnum) const {
      std::vector<cytnx_uint64> tmp;
      return this->_impl->getDegeneracy(qnum, false, tmp);
    }
 
    cytnx_uint64 getDegeneracy(const std::vector<cytnx_int64> &qnum,
                               std::vector<cytnx_uint64> &indices) const {
      indices.clear();
      return this->_impl->getDegeneracy(qnum, true, indices);
    }
 
    const std::vector<cytnx_uint64> &getDegeneracies() const {
      return this->_impl->getDegeneracies();
    }
 
    fermionParity get_fermion_parity(const std::vector<cytnx_int64> &qnum) {
      return this->_impl->get_fermion_parity(qnum);
    }
 
    Bond group_duplicates(std::vector<cytnx_uint64> &mapper) const {
      Bond out;
      out._impl = this->_impl->group_duplicates(mapper);
      return out;
    }
 
    bool has_duplicate_qnums() const { return this->_impl->has_duplicate_qnums(); }
 
    std::vector<std::vector<cytnx_int64>> calc_reverse_qnums() {
      return this->_impl->calc_reverse_qnums();
    }
 
    void Save(const std::string &fname) const;
 
    void Save(const char *fname) const;
 
    static cytnx::Bond Load(const std::string &fname);
 
    static cytnx::Bond Load(const char *fname);
 
    void _Save(std::fstream &f) const;
    void _Load(std::fstream &f);
 
    bool operator==(const Bond &rhs) const;
 
    bool operator!=(const Bond &rhs) const;
 
    Bond operator*(const Bond &rhs) const { return this->combineBond(rhs); }
  };
 
  std::ostream &operator<<(std::ostream &os, const Bond &bin);
}  // namespace cytnx
 
#endif  // CYTNX_BOND_H_