subroutine init_and_write_generalized_cyl_exp(azimuthal_exp_z, azimuthal_exp_r)
 use bmad
 use parameters_bmad

 implicit none

 interface
  subroutine generalize_cyl_exp(azimuthal_exp_z, azimuthal_exp_r, r,phi,z, field)
   use bmad
   implicit none
   type(em_field_struct) field
   real(rp) r,phi,z
   character *120 azimuthal_exp_z, azimuthal_exp_r
  end subroutine
 end interface

 type(em_field_struct) field
 character*120 azimuthal_exp_z, azimuthal_exp_r
 real(rp) phi, z, r
 integer lun

  lun = lunget()
  open(unit=lun, file = trim(directory)//'/'//'field_error.dat')
  phi = 0
  z=0
  r = 7.112
  write(lun,'(a,a)')' Fourier components of total field along magic orbit = ', azimuthal_exp_z
  write(lun,'(a,a)')' Fourier components of radial field along magic orbit = ', azimuthal_exp_r
  write(lun,'(6a12)') 'r','phi','z', 'Br','Bz','Bphi'
  do while(phi <= twopi)
   call generalize_cyl_exp(azimuthal_exp_z, azimuthal_exp_r, r,phi,z, field)
   write(lun,'(6es12.4)') r,phi,z,field%B
   phi = phi + 0.01
 end do
 close(unit=lun)
 return
end