How to express a constraint with fmincon

I want to use fmincon and i have this constraint:

0<x(1)<5
0<x(2)<5
0<x(3)<x(4)
0<x(4)<1

I use this syntax:

x0=[ 1 1 0.2 0.5];
lb=[0 0 0 0];
ub=[5 5 ? 1];

x=fmincon(fun,x0,[],[],[],[],lb,ub);

How can i express x(3)<x(4)?

Answer 1

[Matt J]

Using linear inequalities

   A=[0 0 1 -1];
   b=0;

   lb=[0 0 0 0];
   ub=[5 5 inf 1];

   x=fmincon(fun,x0,A,b,[],[],lb,ub);

[John]

And if i use ub=[5 5 1 1] will i have any problem with the linear inequality?

[Matt J]

No, I can't see how that would make the problem infeasible. What happened when you tried it?

[John]

fmincon failed but i used patternsearch instead (with the same constraints) and it worked.