module Geo::Distance
Public Instance Methods
calc(loc1, loc2)
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# File lib/mealib/geo/distance.rb, line 5 def calc(loc1, loc2) rad_per_deg = Math::PI / 180 # PI / 180 rkm = 6371 # Earth radius in kilometers rm = rkm * 1000 # Radius in meters dlat_rad = (loc2[0] - loc1[0]) * rad_per_deg # Delta, converted to rad dlon_rad = (loc2[1] - loc1[1]) * rad_per_deg lat1_rad, lon1_rad = loc1.map { |i| i * rad_per_deg } lat2_rad, lon2_rad = loc2.map { |i| i * rad_per_deg } a = Math.sin(dlat_rad / 2) ** 2 + Math.cos(lat1_rad) * Math.cos(lat2_rad) * Math.sin(dlon_rad / 2) ** 2 c = 2 * Math.atan2(Math.sqrt(a), Math.sqrt(1 - a)) rm * c # Delta in meters end