function computeDistance(lat1, lng1, lat2, lng2) { var radLat1 = (lat1 * Math.PI) / 180.0; var radLat2 = (lat2 * Math.PI) / 180.0; var a = radLat1 - radLat2; var b = (lng1 * Math.PI) / 180.0 - (lng2 * Math.PI) / 180.0; var s = 2 * Math.asin( Math.sqrt( Math.pow(Math.sin(a / 2), 2) + Math.cos(radLat1) * Math.cos(radLat2) * Math.pow(Math.sin(b / 2), 2) ) ); s = s * 6378.137; // EARTH_RADIUS; s = Math.round(s * 10000) / 10000; return s; } module.exports = { computeDistance };