如何使用经度和纬度值计算两个位置之间的距离

Question

这里我的代码我在下面的代码中使用它们的纬度和经度来计算两个位置之间的距离.这是错误的距离.有时候变得正确,有时会变得无关紧要.

我们从数据库获取lat1和lng1.

//getting lat2 and lng2 from GPS as below

public class MyLocationListener implements LocationListener {

  @Override
  public void onLocationChanged(Location loc)
  {
    lat2=loc.getLatitude();
    lng2=loc.getLongitude();
    String Text = "My current location is: " +"Latitud = "+ loc.getLatitude() +"Longitud = " + loc.getLongitude();

    //System.out.println("Lat & Lang form Loc"+Text);
    //Toast.makeText( getApplicationContext(), Text,Toast.LENGTH_SHORT).show();
  }

  @Override
  public void onProviderDisabled(String provider)
  {
  }

  @Override
  public void onProviderEnabled(String provider)
  {
  }

  @Override
  public void onStatusChanged(String provider, int status, Bundle extras)
  {
  }


  //Calculating distance
  double earthRadius = 3958.75;

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

Answer 1

有一种android.location.Location.distanceBetween()方法可以很好地完成这项工作.

Android开发人员文档:位置

Answer 2

试试这个代码.

startPoint.distanceTo(endPoint)函数返回这些位置之间的距离(以米为单位).

Location startPoint=new Location("locationA");
startPoint.setLatitude(17.372102);
startPoint.setLongitude(78.484196);

Location endPoint=new Location("locationA");
endPoint.setLatitude(17.375775);
endPoint.setLongitude(78.469218);

double distance=startPoint.distanceTo(endPoint);

这里"距离"是我们在米中所需的结果.我希望它适用于android.

Answer 3

这里以公里(km)为距离

private 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);
    dist = dist * 60 * 1.1515;
    return (dist);
}

private double deg2rad(double deg) {
    return (deg * Math.PI / 180.0);
}

private double rad2deg(double rad) {
    return (rad * 180.0 / Math.PI);
}

Answer 4

在build.gradle中:

compile 'com.google.maps.android:android-maps-utils:0.4'

然后:

public static Double distanceBetween(LatLng point1, LatLng point2) {
    if (point1 == null || point2 == null) {
        return null;
    }

    return SphericalUtil.computeDistanceBetween(point1, point2);
}

Answer 5

如果你有两个位置的对象Location loc1和Location loc2你做

float distance = loc1.distanceTo(loc2);

如果您有经度和纬度值，请使用静态distanceBetween()函数

    float[] results = new float[1];
    Location.distanceBetween(startLatitude, startLongitude,
    endLatitude, endLongitude, results);
    float distance = results[0];