no_digested
parameter[e_tot] = 1e9
!parameter[n_part] = 1e10
parameter[geometry] = open
beginning[beta_a] = 10
beginning[beta_b] = 10

q1: quad, wall = {thickness = 0.1, 
    superimpose = F, ele_anchor_pt = center, 
    section = {type = opaque, s = 1, x0 = 1, y0 = 2, dr_ds = 10, 
      v(1) = {11, 12, 130, 140}, 
      v(2) = {1, 2, 30, 40, 5}, 
      v(3) = {-21, 22} &
    },
    section = {s = 2, v(1) = {1,1}},
    section = {s = 5, v(1) = {1,1}} &
}, l = 10 


lw: line = (q1)
use, lw