js calculates the distance between two longitudes and latitudes

```javascript function getDistance(lat1, lng1, lat2, lng2) { var dis = 0; var radLat1 = toRadians(lat1); var radLat2 = toRadians(lat2); var deltaLat = radLat1 - radLat2; var deltaLng = toRadians(lng1) - toRadians(lng2); var dis = 2 * Math.asin(Math.sqrt(Math.pow(Math.sin(deltaLat / 2), 2) + Math.cos(radLat1) * Math.cos(radLat2) * Math.pow(Math.sin(deltaLng / 2), 2))); return dis * 6378137; function toRadians(d) { return d * Math.PI / 180; } } ``` The distance unit returned is meters