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Sorry if this is a known bug, but I could not find it in this repository, I think I might have seen it in Matplotlib:
When using tissot to plot the theoretical field of view of a satellite looking down to Earth, a ValueError is encountered if the tissot polygon crosses the North Pole. It does not happen on the South Pole.
ValueError: undefined inverse geodesic (may be an antipodal point)
Code snipplet below. I installed Basemap (v1.2.0) through pip.
import matplotlib.pyplot as plt
from mpl_toolkits.basemap import Basemap
import math
earth_radius = 6371000. # m
fig = plt.figure()
m = Basemap(projection='cyl', resolution='l',
llcrnrlat=-90, urcrnrlat=90,
llcrnrlon=-180, urcrnrlon=180)
# define the position of the satellite
position = [300000., 75., 0.] # altitude, latitude, longitude
# radius needed by the tissot method
radius = math.degrees(math.acos(earth_radius / (earth_radius + position[0])))
m.tissot(position[2], position[1], radius, 100, facecolor='tab:blue', alpha=0.3) # longitude, latitude
m.scatter(position[2], position[1], marker='*', c='tab:red')
plt.show()
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