Module: Calculations

Defined in:
lib/klimt/util/calculations.rb

Constant Summary collapse

RADIUS =

Haversine formula for spherical distance See: rosettacode.org/wiki/Haversine_formula#Ruby

6371

Class Method Summary collapse

Class Method Details

.deg2rad(lat, long) ⇒ Object 



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# File 'lib/klimt/util/calculations.rb', line 14

def self.deg2rad(lat, long)
  [lat * PI / 180, long * PI / 180]
end

.spherical_distance(start_latlng, end_latlng) ⇒ Object

rough radius of the Earth, in kilometers



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# File 'lib/klimt/util/calculations.rb', line 8

def self.spherical_distance(start_latlng, end_latlng)
  lat1, long1 = deg2rad(*start_latlng)
  lat2, long2 = deg2rad(*end_latlng)
  2 * RADIUS * asin(sqrt(sin((lat2 - lat1) / 2)**2 + cos(lat1) * cos(lat2) * sin((long2 - long1) / 2)**2))
end