Recognize the equation of a surface of revolution

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Yesterday, I asked a question about the critic points of the surface

$$z = (x^2 + y^2)e^{-(x^2 + y^2)}$$ and my question was if I had a easier way to classify the critic points of this surfaces without calculating the determinant of the Hessian matrix. Fortunately, I've find out that surface was a revolution surface, which made my job of classifying the points much easier. Unfortunately, I couldn't conclude it by myself, since I do not know (if there is one) the general formula of a rotation surface around the $z$-axis ($y$ or $x$ too).

I couldn't find much about it in the calculus books that I know and searching about it, I didn't make much progress too.

So, is there any general formula for a surface of revolution?

Thanks in advance!

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If the surface is given by $z=f(x^2+y^2)$, then it is a surface of revolution around the $z$ axis because its level curves are circles.

However, it may not be as easy to see that $z=f(x^2+y^2)$ as it is in your example. Moreover, the surface may have some other axis of revolution, which will make it even harder to spot.