Question

我正在使用Haversine公式来计算地球上两点之间的距离。我有以下代码：

    var app = angular.module('app', []);
app.controller('firstCtrl', function($scope, $timeout) {
  var myLat, myLon, locLat, locLon;
  navigator.geolocation.watchPosition(GetLocation)

  $scope.ASiteLocs = [{
    "name": "IL5077 BRUSSELS",
    "styleUrl": "#waypoint",
    "Point": {
      "coordinates": "-90.58543899999999,38.955472,0"
    }
  }, {
    "name": "IL5076 KAMPSVILLE",
    "styleUrl": "#waypoint",
    "Point": {
      "coordinates": "-90.661923,39.29403,0"
    }
  }, {
    "name": "IL5146 CARROLLTON",
    "styleUrl": "#waypoint",
    "Point": {
      "coordinates": "-90.39965700000001,39.309142,0"
    }
  }, {
    "name": "IL5153 GREENFIELD",
    "styleUrl": "#waypoint",
    "Point": {
      "coordinates": "-90.208747,39.364077,0"
    }
  }];
  $scope.SSiteLocs = [];
  $scope.SiteLocs = $scope.SSiteLocs.concat($scope.ASiteLocs);
  repoSortOrder = "site.name";


  function GetLocation(location, myLat, myLon) {
    myLat = location.coords.latitude;
    myLon = location.coords.longitude;
    document.getElementById("lat").innerHTML = myLat;
     document.getElementById("lon").innerHTML = myLon;
    $timeout(function() {
      calculate();
    });

  }

  $scope.getCoordDistance = function(myLat, myLon, locLat, locLon) {
    var lat1 = locLat; //41.887055
    var lon1 = locLon; //-88.469233
    var lat2 = myLat; //41.888668
    var lon2 = myLon; //-87.640371

    var R = 3959;
    var x1 = lat2 - lat1;
    var dLat = x1 * Math.PI / 180;
    var x2 = lon2 - lon1;
    var dLon = x2 * Math.PI / 180;
    a = Math.sin(dLat / 2) * Math.sin(dLat / 2) +
      Math.cos(lat1 * Math.PI / 180) * Math.cos(lat2 * Math.PI / 180) *
      Math.sin(dLon / 2) * Math.sin(dLon / 2);
    c = 2 * Math.atan2(Math.sqrt(a), Math.sqrt(1 - a));
    var d = R * c;
    return d;

  };


  angular.forEach($scope.SSiteLocs, function(object) {
    object.carrier = 'Sprint';
  });
  angular.forEach($scope.ASiteLocs, function(object) {
    object.carrier = 'AT&T';
  });
var i = 0;
locX = 1;
  var calculate = function() {
    angular.forEach($scope.SiteLocs, function(location) {
      var clength = location.Point.coordinates.length;
      if (location.Point.coordinates.substring(clength - 2, clength) === ",0") {
        location.Point.coordinates = location.Point.coordinates.substring(0, clength - 2).split(",");
        Lat = location.Point.coordinates[0];
        Lon = location.Point.coordinates[1];
        Com = ",";
        location.Point.coordinates = Lon.concat(Com, Lat);
      myLat = Number(document.getElementById("lat").innerHTML)
      myLon = Number(document.getElementById("lon").innerHTML)

      locLat = Lat;
      locLon = Lon;
      d = $scope.getCoordDistance(myLat, myLon, locLat, locLon);
      location.distance = d.toFixed(1);

    if(i < 15){
      console.log("********LOCATON " + locX + "***********")
      console.log("myCoords: " + myLat + "," + myLon);
      console.log("locCoords: " + locLat + "," + locLon);

      console.log("d: " + d);
      console.log("***************************")
      i++;
      locX++;

    }
    }

    });
  };


});

该公式的结果是高达约9-10万，当它们不应该接近那么高时。如果我使用注释掉的坐标，它会正确返回（42.6英里）由于测试坐标工作，我知道这不是一个数学问题。有人知道是什么导致公式无法正常工作吗？
编辑
Here是整个项目的掠夺者。如果这有帮助。
EDIT2
我发现了一些奇怪的东西，结果在不同的浏览器中有所不同，因此，chrome显示一组数字，IE显示另一组，等等。

Answer 1

我不完全确定，在这里，没有测试它，但看起来GetLocation函数通过将它们声明为函数参数来覆盖变量myLat和myLon的闭包范围，所以你要分配location.coords.latitude的值到函数作用域myLat变量中，而不是在代码块开头声明的myLat。

抛出console.log（myLat，myLon）;进入getCoordDistance的开头并检查它们的值。我敢打赌，他们并不是你所期望的。

编辑：它实际上可能是缺少分号和东西。这里有一小段代码重新校准，可以在像jsbin.com这样的隔离环境中运行。它似乎工作正常。你缺少4个分号，所以除非这个赋值失败，否则它应该有效：myLon = Number（document.getElementById（＆＃34; lon＆＃34;）。innerHTML）

有人抱怨变数＆＃34; i＆＃34;和＆＃34; locX＆＃34;没有被定义

var myLat, myLon;

var ASiteLocs = [{
    "name": "IL5077 BRUSSELS",
    "styleUrl": "#waypoint",
    "Point": {
      "coordinates": "-90.58543899999999,38.955472,0"
    }
  }, {
    "name": "IL5076 KAMPSVILLE",
    "styleUrl": "#waypoint",
    "Point": {
      "coordinates": "-90.661923,39.29403,0"
    }
  }, {
    "name": "IL5146 CARROLLTON",
    "styleUrl": "#waypoint",
    "Point": {
      "coordinates": "-90.39965700000001,39.309142,0"
    }
  }, {
    "name": "IL5153 GREENFIELD",
    "styleUrl": "#waypoint",
    "Point": {
      "coordinates": "-90.208747,39.364077,0"
    }
  }];

var SSiteLocs = [];
var SiteLocs = SSiteLocs.concat(ASiteLocs);

function GetLocation(location, myLat, myLon) {
    myLat = location.coords.latitude;
    myLon = location.coords.longitude;
    document.getElementById("lat").innerHTML = myLat;
     document.getElementById("lon").innerHTML = myLon;

  }

function getCoordDistance(myLat, myLon, locLat, locLon) {
    var lat1 = locLat; //41.887055
    var lon1 = locLon; //-88.469233
    var lat2 = myLat; //41.888668
    var lon2 = myLon; //-87.640371

    var R = 3959;
    var x1 = lat2 - lat1;
    var dLat = x1 * Math.PI / 180;
    var x2 = lon2 - lon1;
    var dLon = x2 * Math.PI / 180;
    a = Math.sin(dLat / 2) * Math.sin(dLat / 2) +
      Math.cos(lat1 * Math.PI / 180) * Math.cos(lat2 * Math.PI / 180) *
      Math.sin(dLon / 2) * Math.sin(dLon / 2);
    c = 2 * Math.atan2(Math.sqrt(a), Math.sqrt(1 - a));
    var d = R * c;
    return d;

  };


function calculate() {
    SiteLocs.forEach(function(location) {
      var clength = location.Point.coordinates.length;
      if (location.Point.coordinates.substring(clength - 2, clength) === ",0") {
        location.Point.coordinates = location.Point.coordinates.substring(0, clength - 2).split(",");
        Lat = location.Point.coordinates[0];
        Lon = location.Point.coordinates[1];
        Com = ",";
        location.Point.coordinates = Lon.concat(Com, Lat);
      myLat = -90.208747;
      myLon = 39.364077;

      locLat = Lat;
      locLon = Lon;
      d = getCoordDistance(myLat, myLon, locLat, locLon);
      location.distance = d.toFixed(1);

    //console.log("********LOCATON " + locX + "***********");
      console.log("myCoords: " + myLat + "," + myLon);
      console.log("locCoords: " + locLat + "," + locLon);

      console.log("d: " + d);
      console.log("***************************");

    }

    });
  };

Answer 2

除了kirinthos在回复中所说的内容，您可以通过将结果与Google地图进行比较来轻松测试。我的应用程序中有一个功能可以执行此操作。 point1和point2参数是简单的Latlng对象。我希望结果以千米为单位，因此除以1000。

function calculateDistanceBetweenTwoPoints(point1, point2) {
    return (google.maps.geometry.spherical.computeDistanceBetween(point1, point2) / 1000).toFixed(2);
}

您的HTML页面中需要以下内容：

<script src="https://maps.googleapis.com/maps/api/js?v=3.exp&libraries=geometry,places"></script>

Answer 3

您的点坐标是经度纬度

BRUSSELS",
    "
    "Point": {
      "coordinates": "-90.58543899999999,38.955472

在您的代码中

Lat = location.Point.coordinates[0];
Lon = location.Point.coordinates[1];

在对象中更改它们（首选）请参阅Google latlng class

"Point": {
          "coordinates": "38.955472,-90.58543899999999

或

Lat = location.Point.coordinates[1];
Lon = location.Point.coordinates[0];

使用您的设置距离是大约9000英里，坐标转置距离是aprox 200

Haversine Formula - 结果太高

3 个答案: