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Generate a random geopoint from a fixed distance from a given latitude and longitude

I am writing a java program to generate a all the longitude and latitude with a fixed distance from my my given point. the distance must be exact 2000km, not withub 2000km.
this is my code
public static void getLocation(double x0, double y0, int meters) {
Random random = new Random();
// Convert radius from meters to degrees
double radiusInDegrees = meters / 111000f;
double u = random.nextDouble();
double v = random.nextDouble();
double w = radiusInDegrees * Math.sqrt(u);
double t = 2 * Math.PI * v;
double x = w * Math.cos(t);
double y = w * Math.sin(t);
// Adjust the x-coordinate for the shrinking of the east-west distances
// double new_x = x / Math.cos(Math.toRadians(y0));
double foundLongitude = x + x0;
double foundLatitude = y + y0;
System.out.println("Longitude: " + foundLongitude + " Latitude: " + foundLatitude );
}
How do I make all the point generate equal distance from the geo point, like forming a circle?

public static void generatePoint(double latitude, double longitude, double distanceInMetres, double bearing) {
Random random = new Random();
//int bear = random.nextInt(360);
double brngRad = Math.toRadians(bearing);
double latRad = Math.toRadians(latitude);
double lonRad = Math.toRadians(longitude);
int earthRadiusInMetres = 6371000;
double distFrac = distanceInMetres / earthRadiusInMetres;
double latitudeResult = Math.asin(Math.sin(latRad) * Math.cos(distFrac) + Math.cos(latRad) * Math.sin(distFrac) * Math.cos(brngRad));
double a = Math.atan2(Math.sin(brngRad) * Math.sin(distFrac) * Math.cos(latRad), Math.cos(distFrac) - Math.sin(latRad) * Math.sin(latitudeResult));
double longitudeResult = (lonRad + a + 3 * Math.PI) % (2 * Math.PI) - Math.PI;
System.out.println("bearing: "+bearing+ ", latitude: " + Math.toDegrees(latitudeResult) + ", longitude: " + Math.toDegrees(longitudeResult));
}
need to add bearing

For anyone looking, this is how I implemented this code in JavaScript:
function generatePoint(
latitude,
longitude,
distanceInMetres,
bearing = Math.floor(Math.random() * (360 - 1) + 1)
) {
const brngRad = deg2Rad(bearing);
const latRad = deg2Rad(latitude);
const lonRad = deg2Rad(longitude);
const EARTH_RADIUS_IN_METRES = 6371000;
const distFrac = distanceInMetres / EARTH_RADIUS_IN_METRES;
const latitudeResult = Math.asin(
Math.sin(latRad) * Math.cos(distFrac) +
Math.cos(latRad) * Math.sin(distFrac) * Math.cos(brngRad)
);
const a = Math.atan2(
Math.sin(brngRad) * Math.sin(distFrac) * Math.cos(latRad),
Math.cos(distFrac) - Math.sin(latRad) * Math.sin(latitudeResult)
);
const longitudeResult =
((lonRad + a + 3 * Math.PI) % (2 * Math.PI)) - Math.PI;
return {
latitude: rad2Deg(latitudeResult),
longitude: rad2Deg(longitudeResult),
bearing,
};
}
function deg2Rad(deg) {
return deg * (Math.PI / 180);
}
function rad2Deg(rad) {
return rad * (180 / Math.PI);
}
It will also generate a random bearing if none is provided

distance not showing correctly using the latitude and longitude android

I have a app where I am showing the nearest event (place) distance in km using the Latitude and Longitude. Users latitude and longitude is variable but events latitude and longitude are fixed.However, I am not able to get the correct distance is km. for example correct distance is 6.7 km in google map but its showing 8663.90 km. I am novice in android so unable to get the solution. any help will be great!! my codes are
{ double doubleInstance = d.getDistance(Lat1, Lon1, d.getLatitude(), d.getLongitude(), "N");
String dInstance = String.format("%.2f",doubleInstance);
lblview1.setText(" " + String.valueOf(dInstance) + " Km"); }
and
{ public double getDistance(double lat1, double lon1, double lat2, double lon2, String unit) {
int Radius = 6371;// radius of earth in Km
double dLat = Math.toRadians(lat2 - lat1);
double dLon = Math.toRadians(lon2 - lon1);
double a = Math.sin(dLat / 2) * Math.sin(dLat / 2)
+ Math.cos(Math.toRadians(lat1))
* Math.cos(Math.toRadians(lat2)) * Math.sin(dLon / 2)
* Math.sin(dLon / 2);
double c = 2 * Math.asin(Math.sqrt(a));
double valueResult = Radius * c;
double km = valueResult / 1;
DecimalFormat newFormat = new DecimalFormat("####");
int kmInDec = Integer.valueOf(newFormat.format(km));
double meter = valueResult % 1000;
int meterInDec = Integer.valueOf(newFormat.format(meter));
Log.i("Radius Value", "" + valueResult + " KM " + kmInDec
+ " Meter " + meterInDec);
return Radius * c;
} }

Set your Event location. And get your current location using location manager.
double latitude=lat;
double longitude=lng;
float distance=0;
Location crntLocation=new Location("crntlocation");
crntLocation.setLatitude(currentLatitude);
crntLocation.setLongitude(currentLongitude);
Location eventLocation=new Location("eventlocation");
eventLocation.setLatitude(latitude);
eventLocation.setLongitude(longitude);
//float distance = crntLocation.distanceTo(eventLocation); in meters
distance =crntLocation.distanceTo(eventLocation) / 1000; // in kms

Use Location class method to get distance between two coordinates like;
Location.distanceBetween(obj.getLatitude(), obj.getLongitude(),
mapCircle.getCenter().latitude, mapCircle.getCenter().longitude, distance);

Convert Java code to Delphi about midpoint calculation

I found this Java code to calculate the midpoint between two latitude and longitude:
midpoint between two latitude and longitude
public static void midPoint(double lat1,double lon1,double lat2,double lon2){
double dLon = Math.toRadians(lon2 - lon1);
//convert to radians
lat1 = Math.toRadians(lat1);
lat2 = Math.toRadians(lat2);
lon1 = Math.toRadians(lon1);
double Bx = Math.cos(lat2) * Math.cos(dLon);
double By = Math.cos(lat2) * Math.sin(dLon);
double lat3 = Math.atan2(Math.sin(lat1) + Math.sin(lat2), Math.sqrt((Math.cos(lat1) + Bx) * (Math.cos(lat1) + Bx) + By * By));
double lon3 = lon1 + Math.atan2(By, Math.cos(lat1) + Bx);
//print out in degrees
System.out.println(Math.toDegrees(lat3) + " " + Math.toDegrees(lon3));
}
Anyone can help me to convert this piece of code to Borland Delphi?
With the input like this format:
lat1 = 48.865223,
lon1 = 2.318974
lat2 = 48.865983,
lon2 = 2.321475
I am not sure if that is already in "radian".

lat1 = 48.865223, lon1 = 2.318974
lat2 = 48.865983, lon2 = 2.321475
These coordinates appear to be in degrees. The latitude is too large for radians. You can convert between degrees and radians using DegToRad and RadToDeg. Of course, it's not very hard to multiply and divide by π/180.
The trig functions, sin and cos can be found in the System unit, as can sqrt. For atan2 you need arctan2 from Math.

Calculate distance in miles only between two latitude and longitude

I have some confusion about calculation distance in miles. Whenever i am going to calculate in online it giving different result rather than i am using the below methods.
I need the distance in only miles. What the correction required in the below methods.
public double calculationByDistance(Location loc1, Location loc2) {
int Radius = 6371;// radius of earth in Km
double lat1 = loc1.getLatitude();
double lat2 = loc2.getLatitude();
double lon1 = loc1.getLongitude();
double lon2 = loc2.getLongitude();
double dLat = Math.toRadians(lat2 - lat1);
double dLon = Math.toRadians(lon2 - lon1);
double a = Math.sin(dLat / 2) * Math.sin(dLat / 2)
+ Math.cos(Math.toRadians(lat1))
* Math.cos(Math.toRadians(lat2)) * Math.sin(dLon / 2)
* Math.sin(dLon / 2);
double c = 2 * Math.asin(Math.sqrt(a));
double valueResult = Radius * c;
double km = valueResult / 1;
km = km * 0.62137;
DecimalFormat newFormat = new DecimalFormat("####");
int kmInDec = Integer.valueOf(newFormat.format(km));
double meter = valueResult % 1000;
int meterInDec = Integer.valueOf(newFormat.format(meter));
Log.e("Radius Value", "" + valueResult + " KM " + kmInDec
+ " Meter " + meterInDec);
return Radius * c;
}
If anyone have idea please reply.
Thanks in advance...

Get zipcodes within N miles java client

Goal... Given a Zip code and a number of miles... get all zip codes within N miles.
Found one utility here in .NET: http://www.codeproject.com/Articles/9198/ZIP-Code-Utility
Found another utility in PHP.
Also found this: http://api.geonames.org/findNearbyPostalCodes?postalcode=53714&country=USA&radius=50&username=demo
Is there such a client in java?
UPDATE: I couldn't find one and no one responded, so I went ahead and created one.

I went ahead and wrote one.
package ndd;
public class RadiusBox {
static final Double kEarthRadiusMiles = 3956.0;
public static RadiusBox create(Double latitude, Double longitude, Double radiusInMiles)
{
/*
A point {lat,lon} is a distance d out on the tc radial from point 1 if:
lat = asin (sin (lat1) * cos (d) + cos (lat1) * sin (d) * cos (tc))
dlon = atan2 (sin (tc) * sin (d) * cos (lat1), cos (d) - sin (lat1) * sin (lat))
lon = mod (lon1 + dlon + pi, 2 * pi) - pi
Where:
* d is the distance in radians (an arc), so the desired radius divided by
the radius of the Earth.
* tc = 0 is N, tc = pi is S, tc = pi/2 is E, tc = 3*pi/2 is W.
*/
double lat;
double dlon;
double dLatInRads = latitude * (Math.PI / 180.0);
double dLongInRads = longitude * (Math.PI / 180.0);
double dDistInRad = radiusInMiles / kEarthRadiusMiles;
RadiusBox box = new RadiusBox ();
box.setRadius(radiusInMiles);
// N (tc == 0):
// lat = asin (sin(lat1)*cos(d) + cos(lat1)*sin(d))
// = asin (sin(lat1 + d))
// = lat1 + d
// Unused:
// lon = lon1, because north-south lines follow lines of longitude.
box.setTopLine((dLatInRads + dDistInRad) * (180.0 / Math.PI));
// S (tc == pi):
// lat = asin (sin(lat1)*cos(d) - cos(lat1)*sin(d))
// = asin (sin(lat1 - d))
// = lat1 - d
// Unused:
// lon = lon1, because north-south lines follow lines of longitude.
box.setBottomLine((dLatInRads - dDistInRad) * (180.0 / Math.PI));
// E (tc == pi/2):
// lat = asin (sin(lat1)*cos(d))
// dlon = atan2 (sin(tc)*sin(d)*cos(lat1), cos(d) - sin(lat1)*sin(lat))
// lon = mod (lon1 + dlon + pi, 2*pi) - pi
lat = Math.asin (Math.sin(dLatInRads) * Math.cos (dDistInRad));
dlon = Math.atan2 (Math.sin(Math.PI / 2.0) * Math.sin (dDistInRad) * Math.cos (dLatInRads), Math.cos (dDistInRad) - Math.sin (dLatInRads)* Math.sin (lat));
box.setRightLine( (((dLongInRads + dlon + Math.PI) % (2.0 * Math.PI)) - Math.PI) * (180.0 / Math.PI));
// W (tc == 3*pi/2):
// lat = asin (sin(lat1)*cos(d))
// dlon = atan2 (sin(tc)*sin(d)*cos(lat1), cos(d) - sin(lat1)*sin(lat))
// lon = mod (lon1 + dlon + pi, 2*pi) - pi
dlon = Math.atan2 (Math.sin (3.0 * Math.PI / 2.0) * Math.sin (dDistInRad) * Math.cos (dLatInRads), Math.cos (dDistInRad) - Math.sin (dLatInRads)* Math.sin (lat));
box.setLeftLine((((dLongInRads + dlon + Math.PI) % (2.0 * Math.PI)) - Math.PI) * (180.0 / Math.PI));
return box;
}
private double bottomLine;
private double topLine;
private double leftLine;
private double rightLine;
private double radius;
public double getBottomLine() {
return bottomLine;
}
public void setBottomLine(double bottomLine) {
this.bottomLine = bottomLine;
}
public double getTopLine() {
return topLine;
}
public void setTopLine(double topLine) {
this.topLine = topLine;
}
public double getLeftLine() {
return leftLine;
}
public void setLeftLine(double leftLine) {
this.leftLine = leftLine;
}
public double getRightLine() {
return rightLine;
}
public void setRightLine(double rightLine) {
this.rightLine = rightLine;
}
public double getRadius() {
return radius;
}
public void setRadius(double radius) {
this.radius = radius;
}
#Override
public String toString() {
return "RadiusBox [bottomLine=" + bottomLine + ", leftLine=" + leftLine
+ ", radius=" + radius + ", rightLine=" + rightLine
+ ", topLine=" + topLine + "]";
}
public String getSqlQuery() {
StringBuilder sb = new StringBuilder();
sb.append ("SELECT * FROM ZIP_CODES WHERE ");
sb.append ("LATITUDE >= ");
sb.append(bottomLine);
sb.append (" AND LATITUDE <= ");
sb.append(topLine);
sb.append (" AND LONGITUDE >= ");
sb.append(leftLine);
sb.append (" AND LONGITUDE <= ");
sb.append(rightLine);
sb.append (" ORDER BY CITY, STATE, ZIP");
return sb.toString();
}
}