Nodejs Distance Calculate distance(lat1,lon1,lat2,lon2)

Method Source Code

function distance(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 =//w w  w  .j  a v  a 2s .c om
    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);
}

Number.prototype.toDeg = function() {
    return this * 180 / Math.PI;
};
Number.prototype.toRad = function() {
    return this * Math.PI / 180;
};

Related

1. calculateDistance(lat2, lon2)

   function calculateDistance(lat2, lon2) {
     var R = 3959; 
     var lat1 = 47.3193057;
     var lon1 = -93.2895824;
     var dLat = (lat2 - lat1).toRad();
     var dLon = (lon2 - lon1).toRad(); 
     var a = Math.sin(dLat / 2) * Math.sin(dLat / 2) +
             Math.cos(lat1.toRad()) * Math.cos(lat2.toRad()) * 
             Math.sin(dLon / 2) * Math.sin(dLon / 2); 
   ...
   

2. distance(lat1, lon1, lat2, lon2)

   exports.distance = function(lat1, lon1, lat2, lon2) {
     var radlat1 = Math.PI * lat1/180;
     var radlat2 = Math.PI * lat2/180;
     var radlon1 = Math.PI * lon1/180;
     var radlon2 = Math.PI * lon2/180;
     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);
   ...
   

3. distance(lat1, lon1, lat2, lon2)

   function distance(lat1, lon1, lat2, lon2) {
     var R = 6371;
     var a = 0.5 - Math.cos((lat2 - lat1) * Math.PI / 180)/2 + 
        Math.cos(lat1 * Math.PI / 180) * Math.cos(lat2 * Math.PI / 180) * 
        (1 - Math.cos((lon2 - lon1) * Math.PI / 180))/2;
     var m = R * 2 * Math.asin(Math.sqrt(a))*1000;
     return Math.floor(m);
   

4. distance(p1, p2)

   function Point(x, y) {
       this.x = x;
       this.y = y;
   function randomPoint() {
       var randomx = randomNumber(WIDTH);
       var randomy = randomNumber(HEIGHT);
       var randomPoint = new Point(randomx, randomy);
       return randomPoint;
   ...
   

5. distance(x1, x2, y1, y2)

   Math.distance = function(x1, x2, y1, y2){
     var x = x2 - x1;
     var y = y2 - y1;
     return Math.sqrt(x * x + y * y);
   };
   

6. distanceBetweenTwoPoints(p1, p2)

   Util.distanceBetweenTwoPoints = function(p1, p2) {
     return Math.sqrt(Math.pow(p2.y - p1.y, 2) + Math.pow(p2.x - p1.x, 2)).toFixed(2);
   };
   

7. distanceOfTimeInWords(from, to)

   window.distanceOfTimeInWords = function (from, to) {
     var distance_in_milliseconds = to - from;
     var distance_in_minutes = Math.round(Math.abs(distance_in_milliseconds / 60000));
     var words = "";
     if (distance_in_minutes == 0) {
       words = "less than a minute";
     } else if (distance_in_minutes == 1) {
       words = "1 minute";
     } else if (distance_in_minutes < 45) {
   ...