The Computation of Azimuth and the Shortest Path between Two Points on the Earth's Surface

In this paper, first, analytic geometry are used to calculate the normal transversal azimuth on the ellipsoid surface, then modification value is calculated to get a more accurate orientation angle. Second, based on geodesic differential equations, segmented cumulation for distance between two points on the ground is brought forward. Each section is a short distance, so the result is more accurate. Moreover, when applyed to the program, angle is all got by anti cotangent function, thus avoiding to cumbersomely judge the quadrant.