geosphere 0.0.1

This small pure python package provides two functions which do computations in spherical trigonometry that are needed for navigating on the surface of the earth.

The function

destination(lat_deg, long_deg, distance_nm, bearing_deg)

returns the latitude and longitude of the location reached by traveling distance_nm nautical miles along the great circle route starting at the location with latitude lat_deg and longitude long_deg and having the specified initial bearing.

The function

distance_bearing(lat1_deg, long1_deg, lat2_deg, long2_deg)

returns the distance in nautical miles and the bearing in degrees from the location given by the first latitude-longitude pair to the location given by the second latitude-longitude pair. If the points are too close together the bearing is 0. If the first point is at a pole, the bearing is 0 or 180, as appropriate. If the points are antipodes, so the bearing is undefined, then the bearing returned is 0.