我目前正在使用下面的功能,它不能正常工作。根据谷歌Maps,这些坐标之间的距离(从59.3293371,13.4877472到59.3225525,13.4619422)是2.2公里,而函数返回1.6公里。我怎样才能使这个函数返回正确的距离?

function getDistanceFromLatLonInKm(lat1, lon1, lat2, lon2) {
  var R = 6371; // Radius of the earth in km
  var dLat = deg2rad(lat2-lat1);  // deg2rad below
  var dLon = deg2rad(lon2-lon1); 
  var a = 
    Math.sin(dLat/2) * Math.sin(dLat/2) +
    Math.cos(deg2rad(lat1)) * Math.cos(deg2rad(lat2)) * 
    Math.sin(dLon/2) * Math.sin(dLon/2)
    ; 
  var c = 2 * Math.atan2(Math.sqrt(a), Math.sqrt(1-a)); 
  var d = R * c; // Distance in km
  return d;
}

function deg2rad(deg) {
  return deg * (Math.PI/180)
}

jsFiddle: http://jsfiddle.net/edgren/gAHJB/


当前回答

用javascript计算两点之间的距离

function distance(lat1, lon1, lat2, lon2, unit) {
        var radlat1 = Math.PI * lat1/180
        var radlat2 = Math.PI * lat2/180
        var theta = lon1-lon2
        var radtheta = Math.PI * theta/180
        var dist = Math.sin(radlat1) * Math.sin(radlat2) + Math.cos(radlat1) * Math.cos(radlat2) * Math.cos(radtheta);
        dist = Math.acos(dist)
        dist = dist * 180/Math.PI
        dist = dist * 60 * 1.1515
        if (unit=="K") { dist = dist * 1.609344 }
        if (unit=="N") { dist = dist * 0.8684 }
        return dist
}

要了解更多细节,请参考这个:参考链接

其他回答

我以前写过一个类似的方程-测试了它,也得到了1.6 km。

你的谷歌地图显示了驾驶距离。

你的函数是按照直线距离计算的。

alert(calcCrow(59.3293371,13.4877472,59.3225525,13.4619422).toFixed(1));



    //This function takes in latitude and longitude of two location and returns the distance between them as the crow flies (in km)
    function calcCrow(lat1, lon1, lat2, lon2) 
    {
      var R = 6371; // km
      var dLat = toRad(lat2-lat1);
      var dLon = toRad(lon2-lon1);
      var lat1 = toRad(lat1);
      var lat2 = toRad(lat2);

      var a = Math.sin(dLat/2) * Math.sin(dLat/2) +
        Math.sin(dLon/2) * Math.sin(dLon/2) * Math.cos(lat1) * Math.cos(lat2); 
      var c = 2 * Math.atan2(Math.sqrt(a), Math.sqrt(1-a)); 
      var d = R * c;
      return d;
    }

    // Converts numeric degrees to radians
    function toRad(Value) 
    {
        return Value * Math.PI / 180;
    }

使用Haversine公式,源代码:

//:::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::
//:::                                                                         :::
//:::  This routine calculates the distance between two points (given the     :::
//:::  latitude/longitude of those points). It is being used to calculate     :::
//:::  the distance between two locations using GeoDataSource (TM) prodducts  :::
//:::                                                                         :::
//:::  Definitions:                                                           :::
//:::    South latitudes are negative, east longitudes are positive           :::
//:::                                                                         :::
//:::  Passed to function:                                                    :::
//:::    lat1, lon1 = Latitude and Longitude of point 1 (in decimal degrees)  :::
//:::    lat2, lon2 = Latitude and Longitude of point 2 (in decimal degrees)  :::
//:::    unit = the unit you desire for results                               :::
//:::           where: 'M' is statute miles (default)                         :::
//:::                  'K' is kilometers                                      :::
//:::                  'N' is nautical miles                                  :::
//:::                                                                         :::
//:::  Worldwide cities and other features databases with latitude longitude  :::
//:::  are available at https://www.geodatasource.com                         :::
//:::                                                                         :::
//:::  For enquiries, please contact sales@geodatasource.com                  :::
//:::                                                                         :::
//:::  Official Web site: https://www.geodatasource.com                       :::
//:::                                                                         :::
//:::               GeoDataSource.com (C) All Rights Reserved 2018            :::
//:::                                                                         :::
//:::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::

function distance(lat1, lon1, lat2, lon2, unit) {
    if ((lat1 == lat2) && (lon1 == lon2)) {
        return 0;
    }
    else {
        var radlat1 = Math.PI * lat1/180;
        var radlat2 = Math.PI * lat2/180;
        var theta = lon1-lon2;
        var radtheta = Math.PI * theta/180;
        var dist = Math.sin(radlat1) * Math.sin(radlat2) + Math.cos(radlat1) * Math.cos(radlat2) * Math.cos(radtheta);
        if (dist > 1) {
            dist = 1;
        }
        dist = Math.acos(dist);
        dist = dist * 180/Math.PI;
        dist = dist * 60 * 1.1515;
        if (unit=="K") { dist = dist * 1.609344 }
        if (unit=="N") { dist = dist * 0.8684 }
        return dist;
    }
}

样例代码是根据LGPLv3许可的。

你使用的是哈弗辛公式,它计算了当乌鸦飞行时球面上两点之间的距离。您提供的谷歌Maps链接显示距离为2.2公里,因为它不是一条直线。

Wolfram Alpha是进行地理计算的一个很好的资源,它还显示了这两点之间的距离为1.652公里。

如果您正在寻找直线距离(如crow文件),则您的函数工作正常。如果你想要的是开车距离(或骑自行车距离、公共交通距离或步行距离),你必须使用一个映射API(谷歌或Bing是最流行的)来获得适当的路线,其中将包括距离。

顺便提一下,谷歌Maps API在其Google . Maps .geometry.spherical命名空间(查找computeDistanceBetween)中提供了一个打包的球面距离方法。这可能比你自己卷更好(首先,它使用了更精确的地球半径值)。

对于挑剔的我们来说,我说的“直线距离”,指的是“球面上的直线”,实际上当然是一条曲线(即大圆距离)。

我写出了求两个坐标之间距离的函数。它将返回以米为单位的距离。

 function findDistance() {
   var R = 6371e3; // R is earth’s radius
   var lat1 = 23.18489670753479; // starting point lat
   var lat2 = 32.726601;         // ending point lat
   var lon1 = 72.62524545192719; // starting point lon
   var lon2 = 74.857025;         // ending point lon
   var lat1radians = toRadians(lat1);
   var lat2radians = toRadians(lat2);

   var latRadians = toRadians(lat2-lat1);
   var lonRadians = toRadians(lon2-lon1);

   var a = Math.sin(latRadians/2) * Math.sin(latRadians/2) +
        Math.cos(lat1radians) * Math.cos(lat2radians) *
        Math.sin(lonRadians/2) * Math.sin(lonRadians/2);
   var c = 2 * Math.atan2(Math.sqrt(a), Math.sqrt(1-a));

   var d = R * c;

   console.log(d)
}

function toRadians(val){
    var PI = 3.1415926535;
    return val / 180.0 * PI;
}

如前所述,函数是计算到目标点的直线距离。如果你想要行车距离/路线,你可以使用谷歌地图距离矩阵服务:

getDrivingDistanceBetweenTwoLatLong(origin, destination) {

 return new Observable(subscriber => {
  let service = new google.maps.DistanceMatrixService();
  service.getDistanceMatrix(
    {
      origins: [new google.maps.LatLng(origin.lat, origin.long)],
      destinations: [new google.maps.LatLng(destination.lat, destination.long)],
      travelMode: 'DRIVING'
    }, (response, status) => {
      if (status !== google.maps.DistanceMatrixStatus.OK) {
        console.log('Error:', status);
        subscriber.error({error: status, status: status});
      } else {
        console.log(response);
        try {
          let valueInMeters = response.rows[0].elements[0].distance.value;
          let valueInKms = valueInMeters / 1000;
          subscriber.next(valueInKms);
          subscriber.complete();
        }
       catch(error) {
        subscriber.error({error: error, status: status});
       }
      }
    });
});
}