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

为Node.JS用户添加这个。您可以使用haversine-distance模块来实现这一点,这样您就不需要自己处理计算。更多信息请参见npm页面。

如何安装:

NPM安装——保存haversine-distance

该模块的使用方法如下:

var haversine = require("haversine-distance");

//First point in your haversine calculation
var point1 = { lat: 6.1754, lng: 106.8272 }

//Second point in your haversine calculation
var point2 = { lat: 6.1352, lng: 106.8133 }

var haversine_m = haversine(point1, point2); //Results in meters (default)
var haversine_km = haversine_m /1000; //Results in kilometers

console.log("distance (in meters): " + haversine_m + "m");
console.log("distance (in kilometers): " + haversine_km + "km");

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;
    }

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)。

大圆距离-从弦长开始

这里有一个应用策略设计模式的优雅解决方案;我希望它有足够的可读性。

TwoPointsDistanceCalculatorStrategy.js:

module.exports = () =>

class TwoPointsDistanceCalculatorStrategy {

    constructor() {}

    calculateDistance({ point1Coordinates, point2Coordinates }) {}
};

GreatCircleTwoPointsDistanceCalculatorStrategy.js:

module.exports = ({ TwoPointsDistanceCalculatorStrategy }) =>

class GreatCircleTwoPointsDistanceCalculatorStrategy extends TwoPointsDistanceCalculatorStrategy {

    constructor() {
        super();
    }

    /**
     * Following the algorithm documented here: 
     * https://en.wikipedia.org/wiki/Great-circle_distance#Computational_formulas
     * 
     * @param {object} inputs
     * @param {array} inputs.point1Coordinates
     * @param {array} inputs.point2Coordinates
     * 
     * @returns {decimal} distance in kelometers
     */
    calculateDistance({ point1Coordinates, point2Coordinates }) {

        const convertDegreesToRadians = require('../convert-degrees-to-radians');
        const EARTH_RADIUS = 6371;   // in kelometers

        const [lat1 = 0, lon1 = 0] = point1Coordinates;
        const [lat2 = 0, lon2 = 0] = point2Coordinates;

        const radianLat1 = convertDegreesToRadians({ degrees: lat1 });
        const radianLon1 = convertDegreesToRadians({ degrees: lon1 });
        const radianLat2 = convertDegreesToRadians({ degrees: lat2 });
        const radianLon2 = convertDegreesToRadians({ degrees: lon2 });

        const centralAngle = _computeCentralAngle({ 
            lat1: radianLat1, lon1: radianLon1, 
            lat2: radianLat2, lon2: radianLon2, 
        });

        const distance = EARTH_RADIUS * centralAngle;

        return distance;
    }
};


/**
 * 
 * @param {object} inputs
 * @param {decimal} inputs.lat1
 * @param {decimal} inputs.lon1
 * @param {decimal} inputs.lat2
 * @param {decimal} inputs.lon2
 * 
 * @returns {decimal} centralAngle
 */
function _computeCentralAngle({ lat1, lon1, lat2, lon2 }) {

    const chordLength = _computeChordLength({ lat1, lon1, lat2, lon2 });
    const centralAngle = 2 * Math.asin(chordLength / 2);

    return centralAngle;
}


/**
 * 
 * @param {object} inputs
 * @param {decimal} inputs.lat1
 * @param {decimal} inputs.lon1
 * @param {decimal} inputs.lat2
 * @param {decimal} inputs.lon2
 * 
 * @returns {decimal} chordLength
 */
function _computeChordLength({ lat1, lon1, lat2, lon2 }) {

    const { sin, cos, pow, sqrt } = Math;

    const ΔX = cos(lat2) * cos(lon2) - cos(lat1) * cos(lon1);
    const ΔY = cos(lat2) * sin(lon2) - cos(lat1) * sin(lon1);
    const ΔZ = sin(lat2) - sin(lat1);

    const ΔXSquare = pow(ΔX, 2);
    const ΔYSquare = pow(ΔY, 2);
    const ΔZSquare = pow(ΔZ, 2);

    const chordLength = sqrt(ΔXSquare + ΔYSquare + ΔZSquare);

    return chordLength;
}

convert-degrees-to-radians.js:

module.exports = function convertDegreesToRadians({ degrees }) {

    return degrees * Math.PI / 180;
};

这是大圆距离-从弦长开始,这里有记录。

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;
}

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