PROCEDURE: mag_to_geo PURPOSE: Converts lattitude and longitude between MAG and GEO coordinates. Uses a simple transformation matrix from Kivelson and Russell, "Intro to Space Physics" which is not very accurate in the polar regions. PARAMETERS: lat The array of lattitudes.(In radians unless degrees keyword set.) lon The array of longitudes.(in radians unless degrees keyword set.) KEYWORDS: degrees Set this if both input and output are to be in degrees. mag Set this to do the inverse transformation, GEO to MAG coordinates. Created by: J.Rauchleiba 1/7/97