rpc/solvers/Propagator.h

#ifndef RPC_PROPAGATOR_H
#define RPC_PROPAGATOR_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 <pscf/solvers/PropagatorTmpl.h> // base class template
#include <prdc/cpu/RField.h>             // member template 
#include <util/containers/DArray.h>      // member template
 
namespace Pscf { template <int D> class Mesh; }
 
namespace Pscf { 
namespace Rpc { 
 
   // Forward declaration
   template <int D> class Block;
 
   using namespace Util;
   using namespace Pscf::Prdc;
   using namespace Pscf::Prdc::Cpu;

   template <int D>
   class Propagator : public PropagatorTmpl< Propagator<D> >
   {
 
   public:
 
      // Public typename aliases

      using Base = PropagatorTmpl< Propagator<D> >;

      using FieldT = RField<D>;
 
      // Member functions

      Propagator();

      ~Propagator();
 
      void setBlock(Block<D>& block);
 
      void allocate(int ns, const Mesh<D>& mesh);
 
      void reallocate(int ns);

      void solve();
  
      void solve(FieldT const & head);
  
      double computeQ() const;

      const FieldT& q(int i) const;

      const FieldT& head() const;

      const FieldT& tail() const;

      Block<D> const & block() const;

      int ns() const;

      bool isAllocated() const;
 
      // Inherited public members with non-dependent names
 
      using Base::nSource;
      using Base::source;
      using Base::partner;
      using Base::setIsSolved;
      using Base::isSolved;
      using Base::hasPartner;
      using Base::isHeadEnd;
      using Base::isTailEnd;
 
   private:
     
      DArray<FieldT> qFields_;

      FieldT work_;

      Block<D>* blockPtr_;

      Mesh<D> const * meshPtr_;

      int ns_;

      bool isAllocated_;

      void computeHead();

      void assign(FieldT& lhs, FieldT const & rhs);
 
   };
 
   // Inline member functions
 
   /*
   * Return q-field at beginning of block.
   */
   template <int D>
   inline 
   typename Propagator<D>::FieldT const& Propagator<D>::head() const
   {  
      UTIL_CHECK(isSolved()); 
      return qFields_[0]; }
 
   /*
   * Return q-field at end of block.
   */
   template <int D>
   inline 
   typename Propagator<D>::FieldT const& Propagator<D>::tail() const
   {
      UTIL_CHECK(isSolved()); 
      UTIL_CHECK(PolymerModel::isThread() || !isTailEnd());
      return qFields_[ns_-1]; 
   }
 
   /*
   * Return q-field at specified step.
   */
   template <int D>
   inline 
   typename Propagator<D>::FieldT const& Propagator<D>::q(int i) const
   {  
      UTIL_CHECK(isSolved()); 
      return qFields_[i]; 
   }
 
   /*
   * Get the associated Block object by const reference.
   */
   template <int D>
   inline 
   Block<D> const & Propagator<D>::block() const
   {
      UTIL_ASSERT(blockPtr_);  
      return *blockPtr_; 
   }
 
   /*
   * Get the number of counter grid points.
   */
   template <int D>
   inline int Propagator<D>::ns() const
   {  return ns_; }
 
   template <int D>
   inline bool Propagator<D>::isAllocated() const
   {  return isAllocated_; }
 
   /*
   * Associate this propagator with a unique block.
   */
   template <int D>
   inline void Propagator<D>::setBlock(Block<D>& block)
   {
      UTIL_ASSERT(blockPtr_);  
      blockPtr_ = &block; 
   }
 
   #ifndef RPC_PROPAGATOR_TPP
   // Suppress implicit instantiation
   extern template class Propagator<1>;
   extern template class Propagator<2>;
   extern template class Propagator<3>;
   #endif
 
}
}
#endif