Vectorized geodetic distance and azimuth on the WGS84 earth ellipsoid

Vector and matrix inputs are permitted, and forward and backward azimuth calculations are optionally output.

Description: In 1975, Vincenty published a rapidly converging algorithm for computing the distance between points on an ellipsoidal earth. The algorithm is precise to within a few millimeters. Since then, his algorithm has since seen significant implementation in geodesy and engineering. After adjusting the algorithm to converge in all cases (the original suffers from convergence failure in a few outlying cases), resolving the azimuth quadrant ambiguity present in the original, and vectorizing, I have provided it here in MATLAB form. The function itself does not require the Mapping Toolbox, but I have provided comparisons to that Toolbox in the "help" comments. This function will provide rapid, extremely precise results. Please see code comments for references.

To the many users who downloaded an earlier implemetation of this algorithm, without vectorized code and without azimuth calculations: thank you for your comments, and for your patience.

Michael Kleder, Sep 2005