Does anyone know why this script isn't working?

function Monte_Carlo(N)
    % This function implements a simple Monte Carlo solution for
    % the two variable Lifeguard Problem.
    % N is the number of randomm points
    clc % Clear screen
    % Define objective function using an anonymous function
    T = @(x1,x2) 1/7*sqrt(50^2+x1.^2)+1/4*sqrt(20^2+(x2-x1).^2)+...
    1/2*sqrt(30^2+(100-x2).^2);
    % Make contour plot
    x1=0:100; x2=x1;
    [X1,X2]=meshgrid(x1,x2);
    Time=T(X1,X2);
    contour(x1,x2,Time);grid;hold on
    xlabel('x_1'); ylabel('x_2'); title(['N = ' num2str(N) ])
    % Make lists of random numbers with uniform distribution
    x1=rand(N,1)*100;
    x2=rand(N,1)*100;
    plot(x1,x2,'ob')
    % Calculate corresponding times
    time=T(x1,x2);
    % Find minimum time and its vector address
    [T_star,i]=min(time);
    plot(x1(i),x2(i),'+r') % Put a small + at the minimum of random points
    plot(81.326,92.472,'+b', 'MarkerSize',15) % Mark global minimum
    hold off
    disp(['T* = ' num2str(T_star) ])
    disp(['x1* = ' num2str(x1(i)) ])
    disp(['x2* = ' num2str(x2(i)) ])
    return

[Rik]

What do you mean with not working? When I run this code I don't any error and I don't see any obviously wrong output.

[Image Analyst]

What did you pass in for N? I used 20 and it worked fine:

[Siamak Seyedzadeh]

Hi Rik

Thanks for your reply. I think the problem was the definition for N.