MATLAB: Implementation of limits on the optimization results

Question

Hi guys, I've want to optimize my problem using "fmincon". I want to put limits on the answers, let's say I want x1 > x2 and x2 > x3 in here:

x = fmincon(fun,x0,A,b,[],[],nonlincon)

how should I implement this kinda constraints?

I've set "A" to [-1 1 0;0 -1 1] and "b" to zeros(size(A,1),1) but I get infeasible results! Shouldn't it work?! Please help me out.

Best regards,

Answer 1

Should it be

b = zeros(size(A,1),1);

An example problem (without nonlinear constraints):

f = @(x) x(1)^2 + x(2)^2 + x(3)^2;
A = [-1  1 0
      0 -1 1];
b = zeros(size(A,1),1);
X = fmincon(f,3:-1:1,A,b);