If a and q don’t have the same sign, it is not convex. If a > 0 as you wrote, that means q > 0 is needed for convexity.
Please read Why isn't CVX accepting my model? READ THIS FIRST!
If a and q don’t have the same sign, it is not convex. If a > 0 as you wrote, that means q > 0 is needed for convexity.
Please read Why isn't CVX accepting my model? READ THIS FIRST!