/**
* Location.cs
*
* Copyright (C) 2008 MaxMind Inc. All Rights Reserved.
*
* This library is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public
* License as published by the Free Software Foundation; either
* version 2.1 of the License, or (at your option) any later version.
*
* This library is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public
* License along with this library; if not, write to the Free Software
* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
*/
using System;
using System.IO;
//using System.Math;
public class Location {
public String countryCode;
public String countryName;
public String region;
public String city;
public String postalCode;
public double latitude;
public double longitude;
public int dma_code;
public int area_code;
public String regionName;
public int metro_code;
private static double EARTH_DIAMETER = 2 * 6378.2;
private static double PI = 3.14159265;
private static double RAD_CONVERT = PI / 180;
public double distance (Location loc) {
double delta_lat, delta_lon;
double temp;
double lat1 = latitude;
double lon1 = longitude;
double lat2 = loc.latitude;
double lon2 = loc.longitude;
// convert degrees to radians
lat1 *= RAD_CONVERT;
lat2 *= RAD_CONVERT;
// find the deltas
delta_lat = lat2 - lat1;
delta_lon = (lon2 - lon1) * RAD_CONVERT;
// Find the great circle distance
temp = Math.Pow(Math.Sin(delta_lat/2),2) + Math.Cos(lat1) * Math.Cos(lat2) * Math.Pow(Math.Sin(delta_lon/2),2);
return EARTH_DIAMETER * Math.Atan2(Math.Sqrt(temp),Math.Sqrt(1-temp));
}
}