The matlab m-file to create the image is listed below.
% ========================================================================
% ruleset settings
% ========================================================================
illness_min_size = 3;
illness_base_factor = 25;
illness_trade_infection = 50;
illness_pollution_factor = 50;
factor_aqueduct = 50;
factor_sewer_system = 30;
% ========================================================================
% city config
% ========================================================================
% city size 1 to 50
size = 1:50;
% pollution = 6 * size
pollution = 6 * size;
% size of the trade city
trade_city_size = 10;
% ========================================================================
% calculate illness
% ========================================================================
ill_size = round( (1- exp(- size / 10)) * 10 * illness_base_factor );
ill_trade = round( 4 * illness_trade_infection / 100 * sqrt(size * trade_city_size) );
ill_pollution = round( illness_pollution_factor / 100 * pollution );
% ========================================================================
% plot it
% ========================================================================
figure();
hold on;
grid on;
grid minor;
ylim([0 50]);
xlim([0 50]);
ylabel('illness');
xlabel('city size');
% basic
factor1 = (100 )/100;
plot(size( 1:50), (ill_size( 1:50) )/10 * factor1, 'b-o');
plot(size( 1:50), (ill_size( 1:50)+ill_trade( 1:50) )/10 * factor1, 'b--*');
plot(size( 1:50), (ill_size( 1:50)+ill_trade( 1:50)+ill_pollution( 1:50))/10 * factor1, 'b-.x');
% aqueduct
factor2 = (100 - factor_aqueduct )/100;
plot(size( 8:50), (ill_size( 8:50) )/10 * factor2, 'g-o');
plot(size( 8:50), (ill_size( 8:50)+ill_trade( 8:50) )/10 * factor2, 'g--*');
plot(size( 8:50), (ill_size( 8:50)+ill_trade( 8:50)+ill_pollution( 8:50))/10 * factor2, 'g-.x');
% sewer system
factor3 = (100 - factor_aqueduct - factor_sewer_system)/100;
plot(size(12:50), (ill_size(12:50) )/10 * factor3, 'k-o');
plot(size(12:50), (ill_size(12:50)+ill_trade(12:50) )/10 * factor3, 'k--*');
plot(size(12:50), (ill_size(12:50)+ill_trade(12:50)+ill_pollution(12:50))/10 * factor3, 'k-.x');
legend( ...
'illness size', ...
'illness size + illness trade', ...
'illness size + illness trade + illness pollution', ...
'(aqueduct) illness size', ...
'(aqueduct) illness size + illness trade', ...
'(aqueduct) illness size + illness trade + illness pollution', ...
'(aqueduct + sewer system) illness size', ...
'(aqueduct + sewer system) illness size + illness trade', ...
'(aqueduct + sewer system) illness size + illness trade + illness pollution', ...
'Location', 'NorthOutside');
% min city size
plot([illness_min_size illness_min_size], [-100 100], 'r-');
disp(' # | (illness) | aqueduct | aqueduct + sewer system');
disp(' | base +trade +pollu. | base +trade +pollu. | base +trade +pollu.');
disp('---+-------------------------+-------------------------+-------------------------');
for ii=5:5:50
disp(sprintf('%2d | %7.3f %7.3f %7.3f | %7.3f %7.3f %7.3f | %7.3f %7.3f %7.3f', ...
ii, ...
factor1 /10 * (ill_size(ii)), ...
factor1 /10 * (ill_size(ii) + ill_trade(ii)), ...
factor1 /10 * (ill_size(ii) + ill_trade(ii) + ill_pollution(ii)), ...
factor2 /10 * (ill_size(ii)), ...
factor2 /10 * (ill_size(ii) + ill_trade(ii)), ...
factor2 /10 * (ill_size(ii) + ill_trade(ii) + ill_pollution(ii)), ...
factor3 /10 * (ill_size(ii)), ...
factor3 /10 * (ill_size(ii) + ill_trade(ii)), ...
factor3 /10 * (ill_size(ii) + ill_trade(ii) + ill_pollution(ii))));
end