anchor.diff:    integer, intent(in) :: ix
     
     integer          :: iLens, iRadial, nBin, nPoints, mPoints, kMin, kMax, kk
  -  real(kind=fPrec) :: rra, frra, xa, ya, xffset, yffset, ele_r1, er1_sq, ele_r2, elenor, elesig, elebet, tmpcof
  -  real(kind=fPrec) :: eleTR2, esg_sq, epsilon
  +  real(kind=fPrec) :: rra, frra, xa, ya, xffset, yffset, ele_r1, ele_r2, elenor, elesig, elebet, tmpcof
  +  real(kind=fPrec) :: eleTR2, epsilon, gteps, lteps
     real(kind=fPrec), allocatable :: cof(:)
   
   ! for FOX
  
positive.code:   ELENOR=elens_geo_norm(iLens)
    ELESIG=elens_sig(iLens)
    ELEBET=elens_beta_lens_beam(iLens)
    ER1_SQ=ELE_R1**2
    ESG_SQ=ELESIG**2
    
    FRRA=zero
    RRA=zero
  
negative.code: !FOX    FRR=FRR*((RV-ELEBET*BETA0)/(ONE-ELEBET*BETA0)) ;
        end if
      end if
     
  !FOX  YY(1)=YY(1)+(FRR*XI)/RR ;
  !FOX  YY(2)=YY(2)+(FRR*YI)/RR ;
    end if
  