% Quality of services vs. Traffic intensity given System capacity
clc; clearvars; close all;
n_ch = [20;40;60]; % number of channels given (capacity)
ln = length(n_ch);
a = 0:100;
la = length(a);
Q = zeros(la,ln);
for c=1:ln
    for j=1:la
        ti = a(j);
        Bc = erlang_r( ti,n_ch(c) );
        Q(j,c) = 1-Bc;
    end
end
f = plot(a',Q);
f(1).LineWidth = 1.5;
% f(1).Marker = 'x';
f(2).LineWidth = 1.5;
% f(2).Marker = 'o';
f(3).LineWidth = 1.5;
% f(3).Marker = 'pentagram';
grid on
title('QoS vs. Traffic intensity')
xlabel({'Traffic intensity', 'a'}), ylabel({'QoS', '1-Bc'})
legend({['# channels = ',num2str(n_ch(1))],['# channels = ',num2str(n_ch(2))],...
['# channels = ',num2str(n_ch(3))]}, 'Location','northeast')