anchor.diff:    implicit none
   
     ! A.Mereghetti (CERN, BE-ABP-HSS)
  -  ! last modified: 25-02-2019
  +  ! last modified: 02-04-2020
     ! module for handling maps expressed by Chebyshev polynomials
   
     integer, allocatable, save  :: icheby(:)            ! index of chebyshev lens
  
positive.code: subroutine cheby_kick_fox(i,ix)
  
    ! A. Mereghetti (CERN, BE-ABP-HSS)
    ! last modified: 25-04-2019
    ! apply kick of Chebyshev lenses (FOX)
  
    use mod_common, only : beta0, mtcda, brho
  
negative.code:   epsilon=c1m15
    gteps=one+epsilon
    lteps=one-epsilon
    r1lteps=cheby_r1(icheby(ix))*lteps
    r2gteps=cheby_r2(icheby(ix))*gteps
    
    XCLO=cheby_offset_x(icheby(ix))
    YCLO=cheby_offset_y(icheby(ix))
  