I am posting the sample code here. I cannot understand how to make this constraint compatible with the CVX DCP, I have tried many variations of the code yet I am unable to remove this error.
interference = [1 4 4 1;
3 1 1 3;
2 1 1 2;
1 1 1 1];
cvx_begin
variable z(4,1)
minimize sum(z)
subject to
for a = 1:4
for b = 1:4
x = interference(a,b);
log(z(x) + z(a))./log(2) >= log(z(x))./log(2);
end
end
cvx_end
For example, The Hessian of log(x + y) - log(x) with respect to x and y, evaluated at x = y = 1, has one positive and one negative eigenvalue, and therefore is indefinite (neither convex nor concave). Therefore it is not allowed in CVX, and can not be transformed into something which will be allowed.