anchor.diff:    ! A. Mereghetti (CERN, BE-ABP-HSS)
     ! last modified: 06-04-2020
     ! apply kick of Chebyshev lenses (FOX)
  +  ! NB: for derivatives of polynomials, do not follow what is suggested by
  +  !     G.Stancari, but get d(Tn(u))/du from its definition
   
     use mod_common, only : beta0, mtcda, brho
     use mod_settings, only : st_debug
  
positive.code:     ! normalised variables
  !FOX  UU=XI/REFR ;
  !FOX  VV=YI/REFR ;
      ! normalisation factors of derivatives
  !FOX  FU=(ONE-UU)*(ONE+UU) ;
  !FOX  FV=(ONE-VV)*(ONE+VV) ;
      
      ! fox: T/TP arrays go from 1 to NN
      ! - polynomials:
  
negative.code: subroutine cheby_getKick( xx, yy, dxp, dyp, iTable )
  
    ! A. Mereghetti (CERN, BE-ABP-HSS)
    ! last modified: 06-04-2020
    ! compute kicks from Chebyshev polinomials - see FermiLAB-FN-0972-APC
    ! coordinates and kicks are in the map reference frame!
    ! NB: for derivatives of polynomials, do not follow what is suggested by
    !     G.Stancari, but get d(Tn(u))/du from its definition
  
    use numerical_constants, only : zero, one, two, c1m3, c1e3
  
  