syssolver_OPTeigbicg_params.h

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// -*- C++ -*-
/*! \file
 *  \brief Solve a biCG system
 */
 
#ifndef __syssolver_OPTeigbicg_params_h__
#define __syssolver_OPTeigbicg_params_h__
 
#include "chromabase.h"
 
 
namespace Chroma
{
 
  //! Params for EigBiCG inverter
  /*! \ingroup invert */
  struct SysSolverOptEigBiCGParams
  {
    SysSolverOptEigBiCGParams();
    SysSolverOptEigBiCGParams(XMLReader& in, const std::string& path);
    
    Real RsdCG ;           /*!< CG residual */
    int  MaxCG ;           /*!< Maximum CG iterations */
    int  PrintLevel ;      /*!< Debugg level */
    int  Neig       ;      /*!< number of eigenvectors to compute  */
    int  Nmax       ;      /*!< number of basis vectors */
    int  esize      ;      /*!< 2*lde+2*nev <= esize <= 2*(nev+1)*lde */
    int  Neig_max   ;      /*!< maximum number of eigenvectors to be refined*/
 
    Real restartTol ;      /*!< CG  restart tolerence: restart when 
                              |res|<restartTol*|b-A x(0)| */
 
    Real NormAest ; /* an estimate of the norm2 of the Matrix */
 
    std::string sort_option;   /* (IN) option for sorting eigenvalues computed by eigbicg
                             'M' for smallest magnitude and 'R' for smallest real part*/
 
    Real epsi;            /* (IN) threshold used to check if two eignvalues are conjugate pairs:
                                   if( imag(x)*imag(y) < 0  and
                                   abs(imag(x)+imag(y))/abs(x+y) < epsi and
                                   abs(real(x)-real(y)) / abs(x+y) < epsi )
                                   then x and y are considered to be conjugate, otherwise they are not.*/
    
    int ConvTestOpt;       /* (IN)option for how to determine convergence of the linear system
                              1  means norm(residual) < tol*norm(b)
                              2  means norm(residual) < MAX( tol*norm(b), MACHEPS*(AnormEst*norm(x)+norm(b)))
                              with MACHEPS=1e-7 for single precision version and 1e-16 for double precision version.*/
    bool  cleanUpEvecs ; /*!< clean up evecs upon destruction of SystemSolver*/
    std::string eigen_id ; /*!< named buffer holding the eigenvectors */
 
    struct File_t
    {
      bool read ;
      bool write ;
      std::string   file_name;
      QDP_volfmt_t  file_volfmt;
    } file;
 
    
    void defaults(){
      RsdCG = 1.0e-8;
      MaxCG = 1000;
      PrintLevel=2;
      restartTol = zero;
 
      Neig =0 ;
      Neig_max =0 ;
      esize = 4 ;
      NormAest = 5.0 ;
 
      sort_option = "M";
 
      epsi = 1.0e-8 ;
 
      ConvTestOpt = 1 ;
 
      cleanUpEvecs=false;
      eigen_id="NULL";
 
      //IO control                                                                                               
      file.file_name = eigen_id ;
      file.file_volfmt = QDPIO_SINGLEFILE ;
 
 
      file.read   = false;
      file.write  = false;
 
    }
 
  };
 
 
  // Reader/writers
  /*! \ingroup invert */
  void read(XMLReader& xml, const std::string& path, SysSolverOptEigBiCGParams& param);
 
  /*! \ingroup invert */
  void write(XMLWriter& xml, const std::string& path, const SysSolverOptEigBiCGParams& param);
 
} // End namespace
 
#endif