foo.cr

# crystal build foo.cr --release
# ./foo 37.7749 -122.4194 34.0522 -118.2437
#
# Around 0.08s.

module GeoCalculator
  EARTH_RADIUS_IN_KM = 6371.0

  def self.distance(lat1, lon1, lat2, lon2)
    dlat = lat2 - lat1
    dlon = lon2 - lon1

    a = Math.sin(dlat/2.0)**2 + Math.cos(lat1)*Math.cos(lat2)* Math.sin(dlon/2.0)**2
    c = 2*Math.atan2(Math.sqrt(a), Math.sqrt(1 - a))

    c*EARTH_RADIUS_IN_KM
  end
end

lat1, lon1, lat2, lon2 = ARGV.map(&.to_f)

d = 0

puts Time.measure {
  i = 0
  while i < 10_000_000
    d += GeoCalculator.distance(lat1, lon1, lat2, lon2)
    i += 1
  end
}

puts d

foo.rb

# ruby foo.rb 37.7749 -122.4194 34.0522 -118.2437
#
# Around 1.92s.

require 'benchmark'

module GeoCalculator
  EARTH_RADIUS_IN_KM = 6371.0

  def self.distance(lat1, lon1, lat2, lon2)
    dlat = lat2 - lat1
    dlon = lon2 - lon1

    a = Math.sin(dlat/2.0)**2 + Math.cos(lat1)*Math.cos(lat2)*Math.sin(dlon/2.0)**2
    c = 2*Math.atan2(Math.sqrt(a), Math.sqrt(1 - a))

    c*EARTH_RADIUS_IN_KM
  end
end

lat1, lon1, lat2, lon2 = ARGV.map(&:to_f)

d = 0

puts Benchmark.measure {
  i = 0
  while i < 10_000_000
    d += GeoCalculator.distance(lat1, lon1, lat2, lon2)
    i += 1
  end
}

puts d