Functions to handle geographical points

These functions are used to allow taup models to process input data with source and receiver locations given as latitudes and longitudes. The functions are set up to handle an elliptical planet model, but we do not have ellipticity corrections for travel times. Although changing the shape of the planet from something other than spherical would change the epicentral distance, the change in the distance for the ray to pass through each layer has a larger effect. We do not make the larger correction.

Public Functions

add_geo_to_arrivals Add geographical information to arrivals.
calc_dist Given the source and receiver location, calculate distance.
calc_dist_azi Given the source and receiver location, calculate the azimuth from the source to the receiver at the source, the backazimuth from the receiver to the source at the receiver and distance between the source and receiver.