Coordinates

CartGrid3D defines (registers) four coordinate systems: cart3d, cart2d, cart1d, and spher3d.

The Cartesian coordinates supplied by this thorn are grid functions with the standard names x, y, and z. To use these coordinates you need to inherit from grid, ie you need to have an

inherits: grid

line in your interface.ccl file. In addition a grid function r is provided, containing the radial coordinate from the origin where

$$r = \sqrt{x^2+y^2+z^2}$$

CartGrid3D registers the lower and upper range of each coordinate with the flesh.