下面是Haversine公式的java实现。

public final static double AVERAGE_RADIUS_OF_EARTH_KM = 6371;
public int calculateDistanceInKilometer(double userLat, double userLng,
  double venueLat, double venueLng) {

    double latDistance = Math.toRadians(userLat - venueLat);
    double lngDistance = Math.toRadians(userLng - venueLng);

    double a = Math.sin(latDistance / 2) * Math.sin(latDistance / 2)
      + Math.cos(Math.toRadians(userLat)) * Math.cos(Math.toRadians(venueLat))
      * Math.sin(lngDistance / 2) * Math.sin(lngDistance / 2);

    double c = 2 * Math.atan2(Math.sqrt(a), Math.sqrt(1 - a));

    return (int) (Math.round(AVERAGE_RADIUS_OF_EARTH_KM * c));
}

请注意，这里我们将答案四舍五入到最近的km。

可能有一个更简单、更正确的解决方案:地球的周长在赤道上是40000公里，在格林威治(或任何经度)周期上约为37000公里。因此:

pythagoras = function (lat1, lon1, lat2, lon2) {
   function sqr(x) {return x * x;}
   function cosDeg(x) {return Math.cos(x * Math.PI / 180.0);}

   var earthCyclePerimeter = 40000000.0 * cosDeg((lat1 + lat2) / 2.0);
   var dx = (lon1 - lon2) * earthCyclePerimeter / 360.0;
   var dy = 37000000.0 * (lat1 - lat2) / 360.0;

   return Math.sqrt(sqr(dx) + sqr(dy));
};

我同意它应该被微调，我自己说过它是一个椭球，所以半径乘以余弦值是不同的。但它更准确一点。与谷歌map相比，误差明显减小。

下面是另一个转换为Ruby代码的代码:

include Math
#Note: from/to = [lat, long]

def get_distance_in_km(from, to)
  radians = lambda { |deg| deg * Math.PI / 180 }
  radius = 6371 # Radius of the earth in kilometer
  dLat = radians[to[0]-from[0]]
  dLon = radians[to[1]-from[1]]

  cosines_product = Math.sin(dLat/2) * Math.sin(dLat/2) + Math.cos(radians[from[0]]) * Math.cos(radians[to[1]]) * Math.sin(dLon/2) * Math.sin(dLon/2)

  c = 2 * Math.atan2(Math.sqrt(cosines_product), Math.sqrt(1-cosines_product)) 
  return radius * c # Distance in kilometer
end

下面是一个Scala实现:

  def calculateHaversineDistance(lat1: Double, lon1: Double, lat2: Double, lon2: Double): Double = {
    val long2 = lon2 * math.Pi / 180
    val lat2 = lat2 * math.Pi / 180
    val long1 = lon1 * math.Pi / 180
    val lat1 = lat1 * math.Pi / 180

    val dlon = long2 - long1
    val dlat = lat2 - lat1
    val a = math.pow(math.sin(dlat / 2), 2) + math.cos(lat1) * math.cos(lat2) * math.pow(math.sin(dlon / 2), 2)
    val c = 2 * math.atan2(Math.sqrt(a), math.sqrt(1 - a))
    val haversineDistance = 3961 * c // 3961 = radius of earth in miles
    haversineDistance
  }

下面是VB的实现。NET，这个实现将根据您传递的Enum值以KM或Miles为单位给您结果。

Public Enum DistanceType
    Miles
    KiloMeters
End Enum

Public Structure Position
    Public Latitude As Double
    Public Longitude As Double
End Structure

Public Class Haversine

    Public Function Distance(Pos1 As Position,
                             Pos2 As Position,
                             DistType As DistanceType) As Double

        Dim R As Double = If((DistType = DistanceType.Miles), 3960, 6371)

        Dim dLat As Double = Me.toRadian(Pos2.Latitude - Pos1.Latitude)

        Dim dLon As Double = Me.toRadian(Pos2.Longitude - Pos1.Longitude)

        Dim a As Double = Math.Sin(dLat / 2) * Math.Sin(dLat / 2) + Math.Cos(Me.toRadian(Pos1.Latitude)) * Math.Cos(Me.toRadian(Pos2.Latitude)) * Math.Sin(dLon / 2) * Math.Sin(dLon / 2)

        Dim c As Double = 2 * Math.Asin(Math.Min(1, Math.Sqrt(a)))

        Dim result As Double = R * c

        Return result

    End Function

    Private Function toRadian(val As Double) As Double

        Return (Math.PI / 180) * val

    End Function

End Class

function getDistanceFromLatLonInKm(position1, position2) {
    "use strict";
    var deg2rad = function (deg) { return deg * (Math.PI / 180); },
        R = 6371,
        dLat = deg2rad(position2.lat - position1.lat),
        dLng = deg2rad(position2.lng - position1.lng),
        a = Math.sin(dLat / 2) * Math.sin(dLat / 2)
            + Math.cos(deg2rad(position1.lat))
            * Math.cos(deg2rad(position2.lat))
            * Math.sin(dLng / 2) * Math.sin(dLng / 2),
        c = 2 * Math.atan2(Math.sqrt(a), Math.sqrt(1 - a));
    return R * c;
}

console.log(getDistanceFromLatLonInKm(
    {lat: 48.7931459, lng: 1.9483572},
    {lat: 48.827167, lng: 2.2459745}
));