1. Prerequisites

Most basic functionalities of planetMagFields require only NumPy, Matplotlib and SciPy. Other than that, the following external libraries are used for a few different functions:

• 2D plotting for map projections other than Hammer : Cartopy library (see more under Projections)

• Potential extrapolation: SHTns library

• Writing vts files for 3D visualisation: PyEVTK library