Calculates distance along a street network between two coordinates provided as origin and destination points on a survey of travel behaviors. Uses Open Street Map API and assumes the mode of travel is walking.
Takes as inputs a latitude and longitude of both an origin point and a destination point.
Deals with instances where one or both points is not provided, as well as instances where the the origin and destination are the same location but were geocoded slightly differently.
As OSM is an open source and volunteer-project, it is recommended to limit requests to 2500 per day.