NormalEquations.h

Go to the documentation of this file.

/*************************************************************************************
 
    Grid physics library, www.github.com/paboyle/Grid 
 
    Source file: ./lib/algorithms/iterative/NormalEquations.h
 
    Copyright (C) 2015
 
Author: Peter Boyle <paboyle@ph.ed.ac.uk>
 
    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.
 
    See the full license in the file "LICENSE" in the top level distribution directory
*************************************************************************************/
/*  END LEGAL */
#ifndef GRID_NORMAL_EQUATIONS_H
#define GRID_NORMAL_EQUATIONS_H
 
NAMESPACE_BEGIN(Grid);

// Take a matrix and form an NE solver calling a Herm solver
template<class Field> class NormalEquations : public LinearFunction<Field>{
private:
  SparseMatrixBase<Field> & _Matrix;
  OperatorFunction<Field> & _HermitianSolver;
  LinearFunction<Field>   & _Guess;
public:

  // Wrap the usual normal equations trick
 NormalEquations(SparseMatrixBase<Field> &Matrix, OperatorFunction<Field> &HermitianSolver,
         LinearFunction<Field> &Guess) 
   :  _Matrix(Matrix), _HermitianSolver(HermitianSolver), _Guess(Guess) {}; 
 
  void operator() (const Field &in, Field &out){
 
    Field src(in.Grid());
    Field tmp(in.Grid());
 
    MdagMLinearOperator<SparseMatrixBase<Field>,Field> MdagMOp(_Matrix);
    _Matrix.Mdag(in,src);
    _Guess(src,out);
    _HermitianSolver(MdagMOp,src,out);  // Mdag M out = Mdag in
 
  }     
};
 
template<class Field> class NormalResidual : public LinearFunction<Field>{
private:
  SparseMatrixBase<Field> & _Matrix;
  OperatorFunction<Field> & _HermitianSolver;
  LinearFunction<Field>   & _Guess;
public:

  // Wrap the usual normal equations trick
 NormalResidual(SparseMatrixBase<Field> &Matrix, OperatorFunction<Field> &HermitianSolver,
         LinearFunction<Field> &Guess) 
   :  _Matrix(Matrix), _HermitianSolver(HermitianSolver), _Guess(Guess) {}; 
 
  void operator() (const Field &in, Field &out){
 
    Field res(in.Grid());
    Field tmp(in.Grid());
 
    MMdagLinearOperator<SparseMatrixBase<Field>,Field> MMdagOp(_Matrix);
    _Guess(in,res);
    _HermitianSolver(MMdagOp,in,res);  // M Mdag res = in ;
    _Matrix.Mdag(res,out);             // out = Mdag res
  }     
};
 
template<class Field> class HPDSolver : public LinearFunction<Field> {
private:
  LinearOperatorBase<Field> & _Matrix;
  OperatorFunction<Field> & _HermitianSolver;
  LinearFunction<Field>   & _Guess;
public:

  // Wrap the usual normal equations trick
 HPDSolver(LinearOperatorBase<Field> &Matrix,
       OperatorFunction<Field> &HermitianSolver,
       LinearFunction<Field> &Guess) 
   :  _Matrix(Matrix), _HermitianSolver(HermitianSolver), _Guess(Guess) {}; 
 
  void operator() (const Field &in, Field &out){
 
    _Guess(in,out);
    _HermitianSolver(_Matrix,in,out);  //M out = in
 
  }     
};
 
 
template<class Field> class MdagMSolver : public LinearFunction<Field> {
private:
  SparseMatrixBase<Field> & _Matrix;
  OperatorFunction<Field> & _HermitianSolver;
  LinearFunction<Field>   & _Guess;
public:

  // Wrap the usual normal equations trick
 MdagMSolver(SparseMatrixBase<Field> &Matrix, OperatorFunction<Field> &HermitianSolver,
         LinearFunction<Field> &Guess) 
   :  _Matrix(Matrix), _HermitianSolver(HermitianSolver), _Guess(Guess) {}; 
 
  void operator() (const Field &in, Field &out){
 
    MdagMLinearOperator<SparseMatrixBase<Field>,Field> MdagMOp(_Matrix);
    _Guess(in,out);
 
    _HermitianSolver(MdagMOp,in,out);  // Mdag M out = Mdag in
 
  }     
};
 
NAMESPACE_END(Grid);
#endif