ga_ex26.m

书籍代码:遗传演算法原理与应用_活用MATLAB(Source Code)

% GA_ex26.m file
% Fin min of a function of 2 varaibles
% Fitness function evaluation of Example 2-6
% See P.218 of King's Computational Intelligence
% in Control Engineering

% PenChen Chou, 6-30-2001

%**********************************************************/
%       User can modify the following in blocks
%**********************************************************/
global MIN_offset MUL_factor LOCUS x_data y_data
MIN_offset=5; LOCUS=1; x_data=[]; y_data=[];
MUL_factor=1;
obj_fcn = 'GA_f26';	% Objective function
range = [-1  -1
          1   1];	% Range of the input variables
IC=[]; elite=1; 
gen_no=50;
popuSize=20;
bit_n=32;
xover_rate=0.5;
mutate_rate=0.01;

x=-1:0.02:1; y=x; [X,Y]=meshgrid(x,y);
Z=X.^2+Y.^2-0.3*cos(3*pi*X)-0.4*cos(4*pi*Y)+0.7;
figure(2);contour(X,Y,Z)
%************************************************************
% call GA written by Chang
tic
%GA_genetic(obj_fcn, range, IC, elite,...
% gen_no, popuSize, bit_n, xover_rate, mutate_rate);
[popu, popu_real, fcn_value, upper, average, lower, ...
        popuSize, gen_no] = GA_genetic(obj_fcn, range,...
        IC, elite, gen_no, popuSize, bit_n, xover_rate,...
        mutate_rate);
t=toc/60;
fprintf('==>  Computation time is (%.2f) minutes.\n',t); 

% Plot locus of optimization process
LAST=length(x_data);
figure(2); hold on
plot(x_data(1),y_data(1),'x');
plot(x_data,y_data);
plot(x_data(LAST),y_data(LAST),'o');
plot(0,0,'*');   % The best position
hold off
title('*=BEST, x=Starting point, o=Ending point')