function [ w, w_pos ] = self_gbeam_propagation( w0, x_lens, f, x0, lambda )
%SELF_GBEAM_PROPAGATION Summary of this function goes here
%   Detailed explanation goes here

n_lens = 3;

w = w0;
w_pos = x0;

for i = 1:n_lens
    x_from_next_lens = x_lens(i) - w_pos(i);
    [w_new, s_new] = gaussian_focus(w(i), x_from_next_lens, f(i), lambda);
    w(i+1) = w_new;
    w_pos(i+1) = x_lens(i) + s_new;
end

% x_pos= x_lens;
% x(1)=w_pos(1);
% waist_prop(1)=w(1);
% 
% x_temp=linspace(x0 ,x_pos(1));
% waist_prop=[waist_prop, w(1)*sqrt(1+((x_temp-w_pos(1))/(pi*w(1)^2/lambda)).^2)];
% x=[x x_temp];
% 
% for i=1:n_lens
%     x_temp=linspace(x_pos(i),x_pos(i+1));     
%     waist_prop=[waist_prop, w(i)*sqrt(1+((x_temp-w_pos(i))/(pi*w(i)^2/lambda)).^2)];  
%     x=[x x_temp];
% end
% 
% x_temp=linspace(x_pos(end),x_pos(end)+abs(f(end)));  
% waist_prop=[waist_prop, w(end)*sqrt(1+((x_temp-w_pos(end))/(pi*w(end)^2/lambda)).^2)];
% x=[x x_temp];
% 
% 
% figure(1)
% plot(x,waist_prop,'r',x,-waist_prop,'r'); 
% 





end