SyBookkeeper.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 SYBOOKKEEPER_CHEMPS2_H
#define SYBOOKKEEPER_CHEMPS2_H

#include "Problem.h"

namespace CheMPS2{
   class SyBookkeeper{

      public:


         SyBookkeeper( const Problem * Prob, const int D );


         SyBookkeeper( const SyBookkeeper & tocopy );

         virtual ~SyBookkeeper();


         const Problem * gProb() const;


         int gL() const;


         int gIrrep( const int orbital ) const;


         int gTwoS() const;


         int gN() const;


         int gIrrep() const;


         int getNumberOfIrreps() const;


         int gNmin( const int boundary ) const;


         int gNmax( const int boundary ) const;


         int gTwoSmin( const int boundary, const int N ) const;


         int gTwoSmax( const int boundary, const int N ) const;


         int gFCIdim( const int boundary, const int N, const int TwoS, const int irrep ) const;


         int gCurrentDim( const int boundary, const int N, const int TwoS, const int irrep ) const;


         bool IsPossible() const;


         void SetDim( const int boundary, const int N, const int TwoS, const int irrep, const int value );


         int gMaxDimAtBound( const int boundary ) const;


         int gTotDimAtBound( const int boundary ) const;


         void restart( const int start, const int stop, const int virtual_dim );

      private:

         // Pointer to the Problem --> constructed and destructed outside of this class
         const Problem * Prob;

         // The number of irreps
         int num_irreps;

         // Contains the minimum particle number possible at a boundary ( array length = L + 1 )
         int * Nmin;

         // Contains the maximum particle number possible at a boundary ( array length = L + 1 )
         int * Nmax;

         // Contains twice the minimum spin projection possible at a boundary & particle number ( array dimensions = ( L + 1 ) x ( Nmax[ boundary ] - Nmin[ boundary ] + 1 )
         int ** TwoSmin;

         // Contains twice the maximum spin projection possible at a boundary & particle number ( array dimensions = ( L + 1 ) x ( Nmax[ boundary ] - Nmin[ boundary ] + 1 )
         int ** TwoSmax;

         // FCI dimensions ( array access: FCIdim[ boundary ][ N - gNmin( boundary ) ][ ( TwoS - gTwoSmin( boundary, N ) ) / 2 ][ irrep ] )
         int **** FCIdim;

         // CUR dimensions ( array access: CURdim[ boundary ][ N - gNmin( boundary ) ][ ( TwoS - gTwoSmin( boundary, N ) ) / 2 ][ irrep ] )
         int **** CURdim;

         // Allocate the arrays
         void allocate_arrays();

         // Construct the FCI dimensions
         void fillFCIdim();
         void fill_fci_dim_right( int **** storage, const int start, const int stop );
         void fill_fci_dim_left(  int **** storage, const int start, const int stop );

         // Get a dimension of FCIdim / CURdim
         int gDimPrivate( int **** storage, const int boundary, const int N, const int TwoS, const int irrep ) const;

         // Scale CURdim with virtual_dim from boundary start to boundary stop ( both included )
         void ScaleCURdim( const int virtual_dim, const int start, const int stop );

         // Copy dimension arrays
         void CopyDim( int **** origin, int **** target );

   };
}

#endif