package urt;
/**¼ÆËã2¸ö¾­Î³¶ÈÖ®¼äµÄ¾àÀë·½·¨*/
public class CaculateDistance {

	private final static double EARTH_RADIUS = 6378.137;

	private static double rad(double d) {
		return d * Math.PI / 180.0;
	}

	/**
	 * ¸ù¾ÝÁ½µã¼ä¾­Î³¶È×ø±ê£¨doubleÖµ£©£¬¼ÆËãÁ½µã¼ä¾àÀ룬µ¥Î»ÎªÃ×
	 */
	public static double GetDistance(double lat1, double lng1, double lat2, double lng2) {
		double radLat1 = rad(lat1);
		double radLat2 = rad(lat2);
		double a = radLat1 - radLat2;
		double b = rad(lng1) - rad(lng2);
		double 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 * EARTH_RADIUS;
		s = (s * 10000) / 10;
		return s;
	}

}