I have been given this equation: $$\rho = \cot (\phi)$$
I have been asked to "describe it in spherical coordinates", giving a verbal explanation.
My work: I assume that the equation is given in standard cylindrical coordinates, $\rho,\phi,z$. So the projection onto the $x-y$ or $z=0$ plane looks like this:
However, I am not sure how to translate it into cylindrical coordinates, or what is meant by a verbal explanation.