AmIteratorGrid.h

#ifndef RPG_AM_ITERATOR_GRID_H
#define RPG_AM_ITERATOR_GRID_H
 
/*
* PSCF - Polymer Self-Consistent Field
*
* Copyright 2015 - 2025, The Regents of the University of Minnesota
* Distributed under the terms of the GNU General Public License.
*/
 
#include "Iterator.h"                        // base class
#include <pscf/iterator/AmIteratorTmpl.h>    // base class template
#include <pscf/iterator/AmbdInteraction.h>   // member variable
#include <util/containers/DArray.h>          // base class argument
#include <util/containers/RingBuffer.h>      // method input variable
 
namespace Pscf {
namespace Rpg
{
 
   template <int D>
   class System;
 
   using namespace Util;

   template <int D>
   class AmIteratorGrid : public AmIteratorTmpl<Iterator<D>, FieldCUDA>
   {
 
   public:

      AmIteratorGrid(System<D>& system);
 
      ~AmIteratorGrid();

      void readParameters(std::istream& in);

      void outputTimers(std::ostream& out) const;
 
      // Inherited public member functions
      using AmIteratorTmpl<Iterator<D>, FieldCUDA>::solve;
      using AmIteratorTmpl<Iterator<D>, FieldCUDA>::clearTimers;
      using Iterator<D>::isFlexible;
      using Iterator<D>::flexibleParams;
      using Iterator<D>::setFlexibleParams;
      using Iterator<D>::nFlexibleParams;
      using Iterator<D>::stress;
 
   protected:
 
      // Inherited protected members
      using ParamComposite::readOptional;
      using ParamComposite::readParamCompositeOptional;
      using ParamComposite::readOptionalFSArray;
      using ParamComposite::setClassName;
      using AmIteratorTmpl<Iterator<D>, FieldCUDA>::verbose;
      using AmIteratorTmpl<Iterator<D>, FieldCUDA>::residual;
      using Iterator<D>::system;
      using Iterator<D>::isSymmetric_;
      using Iterator<D>::isFlexible_;
      using Iterator<D>::flexibleParams_;

      void setup(bool isContinuation);
 
   private:

      AmbdInteraction interaction_;

      double scaleStress_;
 
      // Virtual functions used to implement AM algorithm
      
      void setEqual(FieldCUDA& a, FieldCUDA const & b);

      double dotProduct(FieldCUDA const & a, FieldCUDA const & b);

      double maxAbs(FieldCUDA const & a);

      void updateBasis(RingBuffer<FieldCUDA> & basis, 
                       RingBuffer<FieldCUDA> const & hists);

      void addHistories(FieldCUDA& trial, 
                        RingBuffer<FieldCUDA> const & basis, 
                        DArray<double> coeffs, int nHist);

      void addPredictedError(FieldCUDA& fieldTrial, 
                             FieldCUDA const & resTrial, 
                             double lambda);

      bool hasInitialGuess();
     
      int nElements();

      void getCurrent(FieldCUDA& curr);

      void evaluate();

      void getResidual(FieldCUDA& resid);

      void update(FieldCUDA& newGuess);

      void outputToLog();
 
      // --- Private member functions specific to this implementation --- 
      
      cudaReal findAverage(FieldCUDA const & field);
 
   };
 
   #ifndef RPG_AM_ITERATOR_GRID_TPP
   // Suppress implicit instantiation
   extern template class AmIteratorGrid<1>;
   extern template class AmIteratorGrid<2>;
   extern template class AmIteratorGrid<3>;
   #endif
 
} // namespace Rpg
} // namespace Pscf
#endif