Hi,
The function -xlog(1+y) for scale variable x>0 and scale variable y>0， could be directly used in CVX? More generally, it can be available for vector x and y used in CVX?
The function `-xlog(1+y)` for variables x>0 and variable y>0， could be directly used in CVX?
The determinant of its Hessian is -(1+y)^(-2), therefore it must have one positive eigenvalue and one negative eigenvalue. So the function is indefinite, i.e., neither convex nor concave, and it can not be used in CVX.