Bearing calculation formula:
(lat2) - sin (lat1) .cos (lat2) .cos (Δlong))Bearing is the direction of movement from one place to another (starting from the north, and then clockwise). Although the angle in 2D starts from the east, and then counterclockwise. Therefore, if the angle is what you need, later you need to add 90 degrees to the result, and then return it (add minus).
:
http://www.movable-type.co.uk/scripts/latlong.html
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