/haversine

Crystal implementation of the Haversine formula to calculate distances between two points given their latitudes and longitudes

Primary LanguageCrystalMIT LicenseMIT

haversine

Crystal CI GitHub release Docs License

Crystal implementation of the Haversine formula to calculate distances between two points given their latitudes and longitudes.

Installation

  1. Add the dependency to your shard.yml:

    dependencies:
  haversine:
    github: geocrystal/haversine

  2. Run shards install

Usage

require "haversine"

Distance

Calling Haversine.distance with four latitude/longitude coordinates returns a Haversine::Distance object which can provide output in kilometers, meters, miles, feet, or nautical miles.

Each "coordinates" member must be a pair of coordinates - latitude and longitude.

Haversine.distance accepts of either:

  • Haversine.distance(lat1, lon1, lat2, lon2)
  • Haversine.distance({lat1, lon1}, {lat2, lon2})
  • Haversine.distance([lat1, lon1], [lat2, lon2])
# Tokyo -> Paris
distance = Haversine.distance(35.61488, 139.5813, 48.85341, 2.3488)

distance.to_kilometers     # => 9715.470491159029
distance.to_meters         # => 9715470.491159027
distance.to_miles          # => 6032.710918698025
distance.to_feet           # => 31852713.65072557
distance.to_nautical_miles # => 5242.2799481204265

If you have latitude/longitude pairs stored in an array or tuple, you can alternately provide two arrays/tuples when calling Haversine.distance:

london = [51.500153, -0.126236]
new_york = [40.714268, -74.005974]

distance = Haversine.distance(new_york, london)
distance.to_kilometers # => 5570.482153929098

london = {51.500153, -0.126236}
new_york = {40.714268, -74.005974}

distance = Haversine.distance(new_york, london)
distance.to_kilometers # => 5570.482153929098

haversine

https://www.movable-type.co.uk/scripts/latlong.html

Also you can compare Haversine::Distance objects:

london = [51.500153, -0.126236]
new_york = [40.714268, -74.005974]
shanghai = [31.222220, 121.458060]

distance1 = Haversine.distance(london, new_york)
distance2 = Haversine.distance(london, shanghai)

distance1 < distance2 # => true

Destination

Takes the starting point by latitude, longitude and calculates the location of a destination point given a distance factor in degrees, radians, miles, or kilometers; and bearing in degrees.

Haversine.destination(39, -75, 5000, 90, :kilometers)
# => {26.440010707631124, -22.885355549364313}

Contributing

  1. Fork it (https://github.com/geocrystal/haversine/fork)
  2. Create your feature branch (git checkout -b my-new-feature)
  3. Commit your changes (git commit -am 'Add some feature')
  4. Push to the branch (git push origin my-new-feature)
  5. Create a new Pull Request

Contributors