根据经纬度计算出两点间的距离
package com.jttx.poi.utils;
import com.jttx.poi.entity.Point;
/**
* Created by louis on 2014/9/2.
*/
public class GeoUtils {
/**
* 计算两经纬度点之间的距离(单位:米)
* @param lng1 经度
* @param lat1 纬度
* @param lng2
* @param lat2
* @return
*/
public static double getDistance(double lng1,double lat1,double lng2,double lat2){
double radLat1 = Math.toRadians(lat1);
double radLat2 = Math.toRadians(lat2);
double a = radLat1 - radLat2;
double b = Math.toRadians(lng1) - Math.toRadians(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 * 6378137.0;// 取WGS84标准参考椭球中的地球长半径(单位:m)
s = Math.round(s * 10000) / 10000;
return s;
}
/**
* 计算TP值
* @param curPoint 当前点
* @param relatedPoint 偏移点
* @param isGeography 是否是地理坐标 false为2d坐标
* @return tp值
*/
public static double getDirAngle(Point curPoint,Point relatedPoint,boolean isGeography){
double result = 0;
if(isGeography){
double y2 = Math.toRadians(relatedPoint.getLat());
double y1 = Math.toRadians(curPoint.getLat());
double alpha = Math.atan2(relatedPoint.getLat() - curPoint.getLat(), (relatedPoint.getLng() - curPoint.getLng()) * Math.cos((y2 - y1) / 2));//纬度方向乘以cos(y2-y1/2)
double delta =alpha<0?(2*Math.PI+alpha):alpha;
result = Math.toDegrees(delta);
}else {
double alpha = Math.atan2(relatedPoint.getLat() - curPoint.getLat(), relatedPoint.getLng() - curPoint.getLng());
double delta=alpha<0?(2*Math.PI+alpha):alpha;
result = Math.toDegrees(delta);
}
return result;
}
public static void main(String[] args) {
System.out.println(getDistance(121.446014,31.215937,121.446028464238,31.2158502442799 ));
}
}
来源:http://www.jb51.net/article/62192.htm