“The Graticule Ruby gem makes it super easy to geocode addresses using multiple services. One thing I’ve found in developing Unthirsty is that sometimes a geocoding service either fails to be reached or the address couldn’t be found. So as a precaution, I’ve set up a way for Graticule to failover to another service if a lookup fails. Here’s how.”
– via mattking.org
“The Graticule Ruby gem makes it super easy to geocode addresses using multiple services. One thing I’ve found in developing Unthirsty is that sometimes a geocoding service either fails to be reached or the address couldn’t be found. So as a precaution, I’ve set up a way for Graticule to failover to another service if a lookup fails. Here’s how.”
– via mattking.org
“
var lat2 = Math.asin( Math.sin(lat1)Math.cos(d/R) + Math.cos(lat1)Math.sin(d/R)*Math.cos(brng) );
var lon2 = lon1 + Math.atan2(Math.sin(brng)Math.sin(d/R)Math.cos(lat1), Math.cos(d/R)-Math.sin(lat1)*Math.sin(lat2));
”
Given a start point, initial bearing, and distance, this will calculate the destination point and final bearing travelling along a (shortest distance) great circle arc:
var lat2 = Math.asin( Math.sin(lat1)*Math.cos(d/R) +
Math.cos(lat1)*Math.sin(d/R)*Math.cos(brng) );
var lon2 = lon1 + Math.atan2(Math.sin(brng)*Math.sin(d/R)*Math.cos(lat1),
Math.cos(d/R)-Math.sin(lat1)*Math.sin(lat2));