如何计算由经纬度指定的两点之间的距离?

为了澄清,我想用千米来表示距离;这些点使用WGS84系统,我想了解可用方法的相对准确性。


当前回答

我通过简化公式来简化计算。

下面是Ruby版本:

include Math
earth_radius_mi = 3959
radians = lambda { |deg| deg * PI / 180 }
coord_radians = lambda { |c| { :lat => radians[c[:lat]], :lng => radians[c[:lng]] } }

# from/to = { :lat => (latitude_in_degrees), :lng => (longitude_in_degrees) }
def haversine_distance(from, to)
  from, to = coord_radians[from], coord_radians[to]
  cosines_product = cos(to[:lat]) * cos(from[:lat]) * cos(from[:lng] - to[:lng])
  sines_product = sin(to[:lat]) * sin(from[:lat])
  return earth_radius_mi * acos(cosines_product + sines_product)
end

其他回答

你可以使用CLLocationDistance中的构建来计算这个:

CLLocation *location1 = [[CLLocation alloc] initWithLatitude:latitude1 longitude:longitude1];
CLLocation *location2 = [[CLLocation alloc] initWithLatitude:latitude2 longitude:longitude2];
[self distanceInMetersFromLocation:location1 toLocation:location2]

- (int)distanceInMetersFromLocation:(CLLocation*)location1 toLocation:(CLLocation*)location2 {
    CLLocationDistance distanceInMeters = [location1 distanceFromLocation:location2];
    return distanceInMeters;
}

在你的例子中,如果你想要公里,只要除以1000。

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。

function distance($lat1, $lon1, $lat2, $lon2) { 
    $pi80 = M_PI / 180; 
    $lat1 *= $pi80; $lon1 *= $pi80; $lat2 *= $pi80; $lon2 *= $pi80; 
    $dlat = $lat2 - $lat1; 
    $dlon = $lon2 - $lon1; 
    $a = sin($dlat / 2) * sin($dlat / 2) + cos($lat1) * cos($lat2) * sin($dlon / 2) * sin($dlon / 2);  
    $km = 6372.797 * 2 * atan2(sqrt($a), sqrt(1 - $a)); 
    return $km; 
}

我已经创建了这个小Javascript LatLng对象,可能对某人有用。

var latLng1 = new LatLng(5, 3);
var latLng2 = new LatLng(6, 7);
var distance = latLng1.distanceTo(latLng2); 

代码:

/**
 * latLng point
 * @param {Number} lat
 * @param {Number} lng
 * @returns {LatLng}
 * @constructor
 */
function LatLng(lat,lng) {
    this.lat = parseFloat(lat);
    this.lng = parseFloat(lng);

    this.__cache = {};
}

LatLng.prototype = {
    toString: function() {
        return [this.lat, this.lng].join(",");
    },

    /**
     * calculate distance in km to another latLng, with caching
     * @param {LatLng} latLng
     * @returns {Number} distance in km
     */
    distanceTo: function(latLng) {
        var cacheKey = latLng.toString();
        if(cacheKey in this.__cache) {
            return this.__cache[cacheKey];
        }

        // the fastest way to calculate the distance, according to this jsperf test;
        // http://jsperf.com/haversine-salvador/8
        // http://stackoverflow.com/questions/27928
        var deg2rad = 0.017453292519943295; // === Math.PI / 180
        var lat1 = this.lat * deg2rad;
        var lng1 = this.lng * deg2rad;
        var lat2 = latLng.lat * deg2rad;
        var lng2 = latLng.lng * deg2rad;
        var a = (
            (1 - Math.cos(lat2 - lat1)) +
            (1 - Math.cos(lng2 - lng1)) * Math.cos(lat1) * Math.cos(lat2)
            ) / 2;
        var distance = 12742 * Math.asin(Math.sqrt(a)); // Diameter of the earth in km (2 * 6371)

        // cache the distance
        this.__cache[cacheKey] = distance;

        return distance;
    }
};

我通过简化公式来简化计算。

下面是Ruby版本:

include Math
earth_radius_mi = 3959
radians = lambda { |deg| deg * PI / 180 }
coord_radians = lambda { |c| { :lat => radians[c[:lat]], :lng => radians[c[:lng]] } }

# from/to = { :lat => (latitude_in_degrees), :lng => (longitude_in_degrees) }
def haversine_distance(from, to)
  from, to = coord_radians[from], coord_radians[to]
  cosines_product = cos(to[:lat]) * cos(from[:lat]) * cos(from[:lng] - to[:lng])
  sines_product = sin(to[:lat]) * sin(from[:lat])
  return earth_radius_mi * acos(cosines_product + sines_product)
end