Java之——通过两个点的经纬度计算距离（插曲）

转载请注明出处http://blog.csdn.net/l1028386804/article/details/46970705

从google maps的脚本里扒了段代码，没准啥时会用上。大家一块看看是怎么算的。

 private static final double EARTH_RADIUS = 6378.137;

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

	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 = Math.round(s * 10000) / 10000;
		return s;
	}