I am a MATLAB beginner, I have a function that generates 100 X and Y coordinates for 30 users. X and Y are 30 by 100 matrices. How do I generate the distance between a user and the other 29 users, for each of the 30 users.

NoUsers = 30; s = 100; alpha = 1.5; [x,y] = levywalkfunc(alpha,s); for m = 1:NoUsers [x(m,:),y(m,:)] = levywalkfunc(alpha,s); end for m = 1:NoUsers activeset = setdiff(1:NoUsers,m); for j = activeset for t= 1:s D(m, s) = sqrt((x(m,s) - x(j,s))^2+(y(m,s) - y(j,s))^2); end end

Answer 1

[Giridharan Kumaravelu]

for m = 1:NoUsers
    for j = 1:NoUsers
        for t = 1:s
            D(m,j,t) = sqrt((x(m,t) - x(j,t))^2+(y(m,t) - y(j,t))^2);
        end
    end
end

I believe this is what you were trying to do, which outputs a three dimensional vector of distances of the 100 points between users. This could be very inefficient way doing in MATLAB. The power of MATLAB lies in the efficient built-in functions for matrix operations which can run faster than looping statements.

You could try the dist () function.

Note: {}Code button at the top of the editor is a useful tool to type a clean code.

[David Otu]

The dist () function is exactly what I need. You were very helpful. Thanks.