android - 地理点之间的距离

Question

我在计算两个地理点之间的距离时遇到问题。

地理点是:

position1 = mapView.getProjection().fromPixels(
(int) e.getX(),
(int) e.getY());

还有一个

double lat = 35.1064;
double lng = 22.556412;
GeoPoint position2 = new GeoPoint((int)(lat * 1E6), (int)(lng * 1E6));

然后我创建两个位置:

Location loc = new Location("");                                

loc.setLatitude(position1.getLatitudeE6());

loc.setLongitude(position1.getLongitudeE6());

Location loc2 = new Location("");                               

loc.setLatitude(position2.getLatitudeE6());

loc.setLongitude(position2.getLongitudeE6());

然后我计算距离:

float distance = loc.distanceTo(loc2);

然后我将它四舍五入:

Math.round(distance);

但我得到的结果如下:

1.4331783E7

我做错了什么？

Answer 1

尝试按照我的方法，

    /**
 * 
 * @param lat1 Latitude of the First Location
 * @param lng1 Logitude of the First Location
 * @param lat2 Latitude of the Second Location
 * @param lng2 Longitude of the Second Location
 * @return distance between two lat-lon in float format
 */

public static float distFrom (float lat1, float lng1, float lat2, float lng2 ) 
{
    double earthRadius = 3958.75;
    double dLat = Math.toRadians(lat2-lat1);
    double dLng = Math.toRadians(lng2-lng1);
    double a = Math.sin(dLat/2) * Math.sin(dLat/2) +
    Math.cos(Math.toRadians(lat1)) * Math.cos(Math.toRadians(lat2)) *
    Math.sin(dLng/2) * Math.sin(dLng/2);
    double c = 2 * Math.atan2(Math.sqrt(a), Math.sqrt(1-a));
    double dist = earthRadius * c;

    int meterConversion = 1609;

    return new Float(dist * meterConversion).floatValue();
}