This gem calculates the Haversine distance between two points given their longitude and latitude. This is done using trigonometry without ActiveRecord or SQL. See http://en.wikipedia.org/wiki/Haversine_formula for details on the Haversine formula.
This is a replacement for all geo libraries that use built-in SQL DB functionality for their calculations.
Install & Usage
Install this gem with
gem install haversine. Calling
Haversine.distance with four lat/lon coordinates returns a
Haversine::Distance object which can provide output in kilometers, meters, miles, or feet.
require 'haversine' distance = Haversine.distance(35.61488, 139.5813, 48.85341, 2.3488) distance.class => Haversine::Distance distance.to_miles => 6032.71091869803 distance.to_kilometers => 9715.47049115903 distance.to_meters => 9715470.49115903 distance.to_feet => 31852713.6507256 distance.to_nautical_miles => 5242.2799481204265
Convenience aliases for the measurements exist:
distance.to_kilometers == distance.to_km
distance.to_meters == distance.to_m
distance.to_miles == distance.to_mi
distance.to_feet == distance.to_ft
distance.to_nautical_miles == distance.to_nm
to_m is the distance in meters, not miles.
If you have lat/lon pairs stored in an array, you can alternately provide two arrays when calling
require 'haversine' new_york_city = [40.71427, -74.00597] santiago_chile = [-33.42628, -70.56656] Haversine.distance(new_york_city, santiago_chile).to_miles => 5123.73
Note: Haversine is used in the geo_magic gem
Contributing to haversine
- Check out the latest master to make sure the feature hasn’t been implemented or the bug hasn’t been fixed yet
- Check out the issue tracker to make sure someone already hasn’t requested it and/or contributed it
- Fork the project
- Start a feature/bugfix branch
- Commit and push until you are happy with your contribution
- Make sure to add tests for it. This is important so I don’t break it in a future version unintentionally.
- Please try not to mess with the Rakefile, version, or history. If you want to have your own version, or is otherwise necessary, that is fine, but please isolate to its own commit so I can cherry-pick around it.
Copyright © 2011 Kristian Mandrup. See LICENSE.txt for