How can I measure distance and create a bounding b

Question

I am wanting to find the distance between two different points. This I know can be accomplished with the great circle distance. http://www.meridianworlddata.com/Distance-calculation.asp

Once done, with a point and distance I would like to find the point that distance north, and that distance east in order to create a box around the point.

Answer 1

http://www.movable-type.co.uk/scripts/latlong.html

public static Double distanceBetweenTwoLocationsInKm(Double latitudeOne, Double longitudeOne, Double latitudeTwo, Double longitudeTwo) {
        if (latitudeOne == null || latitudeTwo == null || longitudeOne == null || longitudeTwo == null) {
            return null;
        }

        Double earthRadius = 6371.0;
        Double diffBetweenLatitudeRadians = Math.toRadians(latitudeTwo - latitudeOne);
        Double diffBetweenLongitudeRadians = Math.toRadians(longitudeTwo - longitudeOne);
        Double latitudeOneInRadians = Math.toRadians(latitudeOne);
        Double latitudeTwoInRadians = Math.toRadians(latitudeTwo);
        Double a = Math.sin(diffBetweenLatitudeRadians / 2) * Math.sin(diffBetweenLatitudeRadians / 2) + Math.cos(latitudeOneInRadians) * Math.cos(latitudeTwoInRadians) * Math.sin(diffBetweenLongitudeRadians / 2)
                * Math.sin(diffBetweenLongitudeRadians / 2);
        Double c = 2 * Math.atan2(Math.sqrt(a), Math.sqrt(1 - a));
        return (earthRadius * c);
    }

Answer 2

For Android, there is a simple approach.

 public static float getDistanceInMeter(LatLng start, LatLng end) { 
    float[] results = new float[1];
    Location.distanceBetween(start.latitude, start.longitude, end.latitude, end.longitude, results);
    return results[0];

}

;

https://developer.android.com/reference/android/location/Location#distanceBetween(lat1,lng1,lat2,lng2,output[])

Answer 3

This method would help you find the distance between to geographic location in km.

private double getDist(double lat1, double lon1, double lat2, double lon2)
{
    int R = 6373; // radius of the earth in kilometres
    double lat1rad = Math.toRadians(lat1);
    double lat2rad = Math.toRadians(lat2);
    double deltaLat = Math.toRadians(lat2-lat1);
    double deltaLon = Math.toRadians(lon2-lon1);

    double a = Math.sin(deltaLat/2) * Math.sin(deltaLat/2) +
            Math.cos(lat1rad) * Math.cos(lat2rad) *
            Math.sin(deltaLon/2) * Math.sin(deltaLon/2);
    double c = 2 * Math.atan2(Math.sqrt(a), Math.sqrt(1-a));

    double d = R * c;
    return d;
}

Answer 4

You can use the Java Geodesy Library for GPS, it uses the Vincenty's formulae which takes account of the earths surface curvature.

Implementation goes like this:

import org.gavaghan.geodesy.*;
...
GeodeticCalculator geoCalc = new GeodeticCalculator();
Ellipsoid reference = Ellipsoid.WGS84;
GlobalPosition pointA = new GlobalPosition(latitude, longitude, 0.0);
GlobalPosition userPos = new GlobalPosition(userLat, userLon, 0.0);
double distance = geoCalc.calculateGeodeticCurve(reference, userPos, pointA).getEllipsoidalDistance();

The resulting distance is in meters.

Answer 5

Here is a Java implementation of Haversine formula. I use this in a project to calculate distance in miles between lat/longs.

public static double distFrom(double lat1, double lng1, double lat2, double lng2) {
    double earthRadius = 3958.75; // miles (or 6371.0 kilometers)
    double dLat = Math.toRadians(lat2-lat1);
    double dLng = Math.toRadians(lng2-lng1);
    double sindLat = Math.sin(dLat / 2);
    double sindLng = Math.sin(dLng / 2);
    double a = Math.pow(sindLat, 2) + Math.pow(sindLng, 2)
            * Math.cos(Math.toRadians(lat1)) * Math.cos(Math.toRadians(lat2));
    double c = 2 * Math.atan2(Math.sqrt(a), Math.sqrt(1-a));
    double dist = earthRadius * c;

    return dist;
    }