获得两点间的GPS距离

在android中可采用如下代码获取距离:

public double getDistance(double lat1, double lon1, double lat2, double lon2) {
	float[] results=new float[1];
	Location.distanceBetween(lat1, lon1, lat2, lon2, results);
	return results[0];
}

 

在其他设备若没有类似android的Location的distanceBetween方法开采用如下代码获取:

double distance(double lat1, double lon1, double lat2, double lon2) {
	double theta = lon1 - lon2;
	double dist = Math.sin(deg2rad(lat1)) * Math.sin(deg2rad(lat2))
				+ Math.cos(deg2rad(lat1)) * Math.cos(deg2rad(lat2))
				* Math.cos(deg2rad(theta));
	dist = Math.acos(dist);
	dist = rad2deg(dist);
	double miles = dist * 60 * 1.1515;
	return miles;
}
//将角度转换为弧度
static double deg2rad(double degree) {
	return degree / 180 * Math.PI;
}
//将弧度转换为角度
static double rad2deg(double radian) {
	return radian * 180 / Math.PI;
}

 这个计算得出的结果是英里,如果要转换成公里,需要乘以1.609344,若是海里需要乘以0.8684