cpc/solvers/Propagator.h

#ifndef CPC_PROPAGATOR_H
#define CPC_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/CField.h>             // member template
#include <util/containers/DArray.h>      // member template
 
// Forward declarations
namespace Pscf {
   template <int D> class Mesh;
   namespace Cpc {
      template <int D> class Block;
   }
}
 
namespace Pscf {
namespace Cpc {
 
   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 = CField<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);

      void computeQ(std::complex<double>& Q) 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_;
 
      // Private member functions

      void computeHead();

      void assignField(FieldT & lhs, FieldT const & rhs);
 
   };
 
   // Inline member functions
 
   /*
   * Return q-field at the head (beginning) of the block.
   */
   template <int D> inline
   typename Propagator<D>::FieldT const& Propagator<D>::head() const
   {
      UTIL_CHECK(isSolved());
      return qFields_[0]; }
 
   /*
   * Return q-field at the tail (end) of the 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 a 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_; }
 
   // Explicit instantiation declarations
   extern template class Propagator<1>;
   extern template class Propagator<2>;
   extern template class Propagator<3>;
 
} // namespace Cpc
} // namespace Pscf
#endif