https://www.tankbus.org/wp-content/themes/Tank-theme/js/my_common.js

1function mapboxCalculateRoute(qry, color) {
2	if(typeof color !== 'undefined') color = "#ffc107";
3  $.get('https://api.mapbox.com/matching/v5/mapbox/driving/' + qry + '?geometries=geojson&steps=true&access_token='+token, 
4	function( data ) {
5		if(data.matchings.length > 0){
6			var coords = data.matchings[0].geometry.coordinates;
7			let coords_line = [];
8			for(let i=0; i<coords.length; i++){
9				coords_line.push([coords[i][1],coords[i][0]]);
10			}
11			polylineLayer = L.polyline(coords_line, {color: color}).addTo(myMap)
12			
13		}
14  });  
15}
16
17function averageGeolocation(coords) {
18  if (coords == null) {
19	return coords;
20  }else if(coords.length === 1) {
21	return coords[0];
22  }
23
24  var x = 0.0;
25  var y = 0.0;
26  var z = 0.0;
27
28  // for (var coord of coords) {
29  for (var i=0; i<coords.length ; i++) {
30		var coord = coords[i];
31		var latitude = coord.lat * Math.PI / 180;
32		var longitude = coord.lng * Math.PI / 180;
33
34		x += Math.cos(latitude) * Math.cos(longitude);
35		y += Math.cos(latitude) * Math.sin(longitude);
36		z += Math.sin(latitude);
37  }
38
39  var total = coords.length;
40
41  x = x / total;
42  y = y / total;
43  z = z / total;
44
45  var centralLongitude = Math.atan2(y, x);
46  var centralSquareRoot = Math.sqrt(x * x + y * y);
47  var centralLatitude = Math.atan2(z, centralSquareRoot);
48
49  return {
50	Latitude: centralLatitude * 180 / Math.PI,
51	Longitude: centralLongitude * 180 / Math.PI
52  };
53}