[javascript] 두 좌표간 거리계산 함수

[javascript] 두 좌표간 거리계산 함수

 

function getDistanceFromLatLonInKm(lat1,lng1,lat2,lng2) {
    function deg2rad(deg) {
        return deg * (Math.PI/180)
    }

    var R = 6371; // Radius of the earth in km
    var dLat = deg2rad(lat2-lat1);  // deg2rad below
    var dLon = deg2rad(lng2-lng1);
    var a = 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;
}