Grid/lib/qcd/action/fermion/OverlapWilsonPartialFractionZolotarevFermion.h

#ifndef OVERLAP_WILSON_PARTFRAC_ZOLOTAREV_FERMION_H
#define OVERLAP_WILSON_PARTFRAC_ZOLOTAREV_FERMION_H

#include <Grid.h>

namespace Grid {

  namespace QCD {

    template<class Impl>
    class OverlapWilsonPartialFractionZolotarevFermion : public PartialFractionFermion5D<Impl>
    {
    public:
     INHERIT_IMPL_TYPES(Impl);

      virtual void   Instantiatable(void){};
      // Constructors
    OverlapWilsonPartialFractionZolotarevFermion(GaugeField &_Umu,
						 GridCartesian         &FiveDimGrid,
						 GridRedBlackCartesian &FiveDimRedBlackGrid,
						 GridCartesian         &FourDimGrid,
						 GridRedBlackCartesian &FourDimRedBlackGrid,
						 RealD _mass,RealD _M5,
						 RealD lo,RealD hi,const ImplParams &p= ImplParams()):
      
      // b+c=scale, b-c = 0 <=> b =c = scale/2
      PartialFractionFermion5D<Impl>(_Umu,
				     FiveDimGrid,
				     FiveDimRedBlackGrid,
				     FourDimGrid,
				     FourDimRedBlackGrid,_mass,_M5,p)
	{
	  assert((this->Ls&0x1)==1); // Odd Ls required

	  int nrational=this->Ls;// Odd rational order
	  RealD eps = lo/hi;

	  Approx::zolotarev_data *zdata = Approx::zolotarev(eps,nrational,0);
	  this->SetCoefficientsZolotarev(hi,zdata);
	  Approx::zolotarev_free(zdata);

	}
    };
  }
}
#endif