Any of a number of co-ordinate systems in which a point is identified by parameters identifiable as a distance from some fixed feature in space and one or more subtended angles.
Sub types include:
Circular Polar Coordinates
A two-dimensional coordinate system in which a point is located by its distance from some predefined point (known as the origin) and the angle made by a line joining from the origin to the point and some fixed axis. The angle is typically denoted θ and the distance 'r' (for radius).
Cylindrical Polar Coordinates
A three-dimensional system similar to circular polar coordinates except the angle and radius are measured relative to a fixed straight axis in space, and a third co-ordinate is used, which measures the vertical height above some fixed plane normal to this axis.
Spherical Polar Coordinates
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