API Reference distance v1.0.1
Basic distance calculations for cartesian coordinates for calculting
distances on a single plane. If you are looking to calculating distance
on the surface of Earth, check out the
Calculate great circle distances (shortest travel distance on the surface of a spherical Earth) given a two longitude-latitude pairs. This is an implementation of the Haversine formula and approximates using a spherical (non-ellipsoid) Earth with a mean radius of 6,371,008.8 meters derived from the WGS84 datum.