unprec_wilson_linop_w.h

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// -*- C++ -*-
/*! \file
 *  \brief Unpreconditioned Wilson fermion linear operator
 */
 
#ifndef __unprec_wilson_linop_w_h__
#define __unprec_wilson_linop_w_h__
 
#include "linearop.h"
#include "actions/ferm/linop/dslash_w.h"
 
 
namespace Chroma 
{ 
  //! Unpreconditioned Wilson-Dirac operator
  /*!
   * \ingroup linop
   *
   * This routine is specific to Wilson fermions!
   *
   *                                                      ~      ~+
   * This subroutine applies the unpreconditioned matrix  M  or  M   the std::vector
   * Psi,
   *
   *                       {   ~
   *                       {   M(U) . Psi              if  ISign = PLUS
   *               Chi  =  {
   *                       {   ~   +
   *                       {   M(U)  . Psi             if  ISign = MINUS
   *
   * Algorithm:
 
   * The kernel for Wilson fermions is
 
   *      M  =  (d+M) - (1/2) D'
   *
   */
  
  class UnprecWilsonLinOp : public UnprecLinearOperator<LatticeFermion, 
                    multi1d<LatticeColorMatrix>, multi1d<LatticeColorMatrix> >
  {
  public:
    // Typedefs to save typing
    typedef LatticeFermion               T;
    typedef multi1d<LatticeColorMatrix>  P;
    typedef multi1d<LatticeColorMatrix>  Q;
 
    //! Partial constructor
    UnprecWilsonLinOp() {}
 
    //! Full constructor
    UnprecWilsonLinOp(Handle< FermState<T,P,Q> > fs, const Real& Mass_)
      {create(fs,Mass_);}
 
    //! Full constructor with Anisotropy
    UnprecWilsonLinOp(Handle< FermState<T,P,Q> > fs,
                      const Real& Mass_,
                      const AnisoParam_t& aniso)
      {create(fs,Mass_,aniso);}
 
    //! Destructor is automatic
    ~UnprecWilsonLinOp() {}
 
    //! Return the fermion BC object for this linear operator
    const FermBC<T,P,Q>& getFermBC() const {return D.getFermBC();}
 
    //! Creation routine
    void create(Handle< FermState<T,P,Q> > fs,
                const Real& Mass_);
 
    //! Creation routine with Anisotropy
    void create(Handle< FermState<T,P,Q> > fs,
                const Real& Mass_,
                const AnisoParam_t& aniso);
 
    //! Apply the operator onto a source std::vector
    void operator() (LatticeFermion& chi, const LatticeFermion& psi, enum PlusMinus isign) const;
 
    //! Derivative of unpreconditioned Wilson dM/dU
    void deriv(multi1d<LatticeColorMatrix>& ds_u, 
               const LatticeFermion& chi, const LatticeFermion& psi, 
               enum PlusMinus isign) const;
 
    //! Return flops performed by the operator()
    unsigned long nFlops() const;
 
  private:
    Real fact;  // tmp holding  Nd+Mass
 
    Real Mass;
    WilsonDslash D;
  };
 
} // End Namespace Chroma
 
 
#endif