Geocalc

Documentation: http://hexdocs.pm/geocalc

Calculate distance, bearing and more between latitude/longitude points

All the formulas are adapted from http://www.movable-type.co.uk/scripts/latlong.html

Installation

First, add Geocalc to your mix.exs dependencies:

def deps do
  [{:geocalc, "~> 0.5"}]
end

Then, update your dependencies:

$ mix deps.get

Now, list the :geocalc application as your application dependency:

def application do
  [applications: [:geocalc]]
end

Usage

Calculate distance (in meters) between 2 points

Geocalc.distance_between([50.0663889, -5.7147222], [58.6438889, -3.07])
# => 968853.5464535094

Get destination point given distance (meters) from start and end point

Geocalc.destination_point([50.0663889, -5.7147222], [58.6438889, -3.07], 100_000)
# => {:ok, [50.95412546615634, -5.488452905258299]}

Get destination point given distance (meters) and bearing from start point

Geocalc.destination_point([50.0663889, -5.7147222], 2.123, 100_000)
# => {:ok, [49.58859917965055, -4.533613856982982]}

Calculate bearing from start and end points

Geocalc.bearing([50.0663889, -5.7147222], [58.6438889, -3.07])
# => 0.1591708517503001

Get intersection point given start points and bearings

Geocalc.intersection_point([50.0663889, -5.7147222], 2.123, [55.0663889, -15.7147222], 2.123)
# => {:ok, [48.04228582473962, -1.0347033632388496]}

Geocalc.intersection_point([50.0663889, -5.7147222], 2.123, [50.0663889, -5.7147222], 2.123)
# => {:error, "No intersection point found"}

Get bounding box from a point and radius

berlin = [52.5075419, 13.4251364]
radius = 10_000
Geocalc.bounding_box(berlin, radius)
# => [[52.417520954378574, 13.277235453275123], [52.59756284562143, 13.573037346724874]]

Get geographical center point

berlin = [52.5075419, 13.4251364]
london = [51.5286416, -0.1015987]
rome = [41.9102415, 12.3959161]
Geocalc.geographic_center([berlin, london, rome])
# => [48.810406537400254, 8.785092188535195]

Convert degrees to radians

Geocalc.degrees_to_radians(245)
# => -2.007128639793479

Convert radians to degrees

Geocalc.radians_to_degrees(1.234)
# => 70.70299191914359

Geocalc.Point protocol

Everything which implements Geocalc.Point protocol can be passed as a point argument for any function in this library. We already have implementations for List, Tuple and Map. You can define your own implementations if you need, everything we need to know to do calculations are latitude and longitude.