The Compendium Geometry is an eBook providing facts, formulas and explanations about geometry.

Cylindrical Coordinate System

The cylindrical coordinate system specifies the position of a point P by the combination of its distance to the z-axis (radius ρ), the angle φ between the x-axis and the line OQ, and the elevation along the z-axis. Note, that the angle is positive in counter-clockwise direction and negative in clockwise direction. The value of the angle is measured in radians (0..2π) or degrees (0..360°).

To specify a particular point in a cylindrical coordinate system, you indicate the coordinate values in the form [ρ, φ, z]. The ρ coordinate is called radial coordinate, the φ coordinate is called azimuthal coordinate, and the z coordinate is also called the applicate.

A point in the cylindrical coordinate system.


Last Update: 2010-12-06