Cylindrical Coordinates
The cylindrical coordinate system basically is a combination of the polar coordinate system xy - plane with an additional z - coordinates vertically. In the cylindrical coordinate system, a point P whose Cartesian coordinate is (x, y, z) is represented by the ordered triple (r, θ, z) , where (r, θ) is the polar coordinate of (x, y) and z is the vertical projection along z - axis of P onto xy – plane.