subroutine set_fringe_params(lat,nbranch, DeltaB_onB)
  use bmad
  use muon_mod
  use parameters_bmad
  implicit none
  
  type (lat_struct) lat
!  type (branch_struct), pointer:: branch ! ring
  type (ele_struct), pointer :: slave_ele, g2_ele, inf_ele, fringe_ele
  type(ele_pointer_struct), allocatable:: eles(:)

  integer i
  integer ix
  integer nbranch
  integer n_loc

  real(rp) DeltaB_onB
  real(rp) inflector_angle

  logical err

!scale fringe grid

call lat_ele_locator('FRINGE', lat, eles, n_loc, err)
fringe_ele => eles(1)%ele
fringe_ele%grid_field(1)%field_scale = fringe_ele%grid_field(1)%field_scale*(1.+DeltaB_onB)
print *,'fringe_ele%grid_field(1)%field_scale = ', fringe_ele%grid_field(1)%field_scale 
call set_flags_for_changed_attribute(fringe_ele, fringe_ele%grid_field(1)%field_scale)


 return
end