Talk:Cylindrical coordinate system

This needs a discussion regarding the alternate convention used by physicsts: rho and phi instead of r and theta.

The line element equation looks wrong. Shouldn't it be $d s 2 = d r 2 + r 2 d θ 2 + d z 2$ ?

--The line element is given in vector form; when you calculate the magnitude of it you indeed get the expression above.