expand_od_pairs: Expand origin-destination pairs
Description
This function is used in detailed_itineraries() to update the origins and
destinations datasets.
Usage
expand_od_pairs(origins, destinations, all_to_all)
Arguments
- origins
Passed by detailed_itineraries().
- destinations
Passed by detailed_itineraries().
- all_to_all
Passed by detailed_itineraries().