TensorOperator.h

/*
   CheMPS2: a spin-adapted implementation of DMRG for ab initio quantum chemistry
   Copyright (C) 2013-2016 Sebastian Wouters

   This program 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 2 of the License, or
   (at your option) any later version.

   This program 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 this program; if not, write to the Free Software Foundation, Inc.,
   51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
*/

#ifndef TENSOROPERATOR_CHEMPS2_H
#define TENSOROPERATOR_CHEMPS2_H

#include "Tensor.h"
#include "TensorT.h"
#include "SyBookkeeper.h"

namespace CheMPS2{
   class TensorOperator : public Tensor{

      public:


         TensorOperator( const int boundary_index, const int two_j, const int n_elec, const int n_irrep, const bool moving_right, const bool prime_last, const bool jw_phase, const SyBookkeeper * bk_up, const SyBookkeeper * bk_down );

         virtual ~TensorOperator();


         int gNKappa() const;


         double * gStorage();


         int gKappa( const int N1, const int TwoS1, const int I1, const int N2, const int TwoS2, const int I2 ) const;


         int gKappa2index( const int kappa ) const;


         double * gStorage( const int N1, const int TwoS1, const int I1, const int N2, const int TwoS2, const int I2 );


         int gIndex() const;


         int get_2j() const;


         int get_nelec() const;


         int get_irrep() const;


         void update( TensorOperator * previous, TensorT * mps_tensor_up, TensorT * mps_tensor_down, double * workmem );


         void daxpy( double alpha, TensorOperator * to_add );


         void daxpy_transpose_tensorCD( const double alpha, TensorOperator * to_add );

         void clear();


         double inproduct( TensorOperator * buddy, const char trans ) const;

      protected:

         const SyBookkeeper * bk_up;

         const SyBookkeeper * bk_down;

         int two_j;

         int n_elec;

         int n_irrep;

         bool moving_right;

         int * sector_nelec_up;

         int * sector_irrep_up;

         int * sector_spin_up;

         int * sector_spin_down;


         void update_moving_right( const int ikappa, TensorOperator * previous, TensorT * mps_tensor_up, TensorT * mps_tensor_down, double * workmem );


         void update_moving_left( const int ikappa, TensorOperator * previous, TensorT * mps_tensor_up, TensorT * mps_tensor_down, double * workmem );

         bool prime_last;

         bool jw_phase;

      private:

   };
}

#endif