Delete obsolete spacing function.

@Ternary_model/Ternary_model.m

@@ -63,6 +63,5 @@ classdef Ternary_model < handle
         pt = phi_tot(x, a, b, e, u0, vt)
         g = gradient_analytical(x, a, b, e, vt)
         g0 = gamma0(x, a, b, e_g0, u_g0, vt)
-        sp = spacing(x, a, b, e_g0, u_g0)
     end
 end
\ No newline at end of file

@Ternary_model/spacing.m

-function sp = spacing(x, a, b, e_g0, u_g0)
-    sp = b*atanh(2/(e_g0)*(x-u_g0)-1)-a;
-end
\ No newline at end of file