# Deborah R. Fowler

## Coordinate Systems

Updated on June 22 2013

Most of our work in 3D packages exists in a Cartesian coordinate system. Point locations described with

**( x, y, z )**.

In mathematics and other applications it is often handy to describe things in Polar coordinates. Point locations described by some distance from center, r and an angle from a reference direction, theta. In two dimension,

**(r,angle)**and in three dimensions, ( r, azimuth angle (from x-axis), zenith angle (from z-axis) )

It is simple to convert from one coordinate system to the other. For example, in 2-D: