% Himmelblau's Function # 1
% Range of initial points: -2 <= x <= 2
% Two global minimum: x={-1,1}
% f(x)=0
% Coded by: Ali R. Alroomi | Last Update: 18 Jan. 2015 | www.al-roomi.org
 
clear
clc
warning off
 
xmin=-2;
xmax=2;
R=100000; % steps resolution
x=xmin:(xmax-xmin)/R:xmax;
    
for i=1:length(x)
    f(i)=(x(i).^2-1).^2;
end
 
plot(x,f,'r','LineWidth',2);grid;set(gca,'FontSize',12);
xlabel('x','FontName','Times','FontSize',20,'FontAngle','italic');
ylabel('f(x)','FontName','Times','FontSize',20,'FontAngle','italic');