using System;
namespace ToLatLon_Test
{
class MainClass
{
public static void Main(string[] args)
{
Console.WriteLine("UTM to LatLon test");
string input;
double utmX, utmY;
string Zone;
try {
Console.Write("Enter utmX: ");
input = Console.ReadLine();
utmX = double.Parse(input);
Console.Write("Enter utmY: ");
input = Console.ReadLine();
utmY = double.Parse(input);
Console.Write("Enter UTM Zone: ");
Zone = Console.ReadLine();
Console.WriteLine();
ToLatLon(utmX, utmY, Zone);
} catch(Exception e) {
Console.Write("Error: ");
Console.WriteLine(e.Message);
}
}
public static void ToLatLon(double utmX, double utmY, string utmZone)
{
double latitude = 0;
double longitude = 0;
// Changed from utmZone.Last as the Linq version is much slower than simply indexing
// the last position in the string's array of characters
bool isNorthHemisphere = utmZone[utmZone.Length-1] >= 'N';
var diflat = -0.00066286966871111111111111111111111111;
var diflon = -0.0003868060578;
var zone = int.Parse(utmZone.Remove(utmZone.Length - 1));
var c_sa = 6378137.000000;
var c_sb = 6356752.314245;
var e2 = Math.Pow((Math.Pow(c_sa, 2) - Math.Pow(c_sb, 2)), 0.5) / c_sb;
var e2cuadrada = Math.Pow(e2, 2);
var c = Math.Pow(c_sa, 2) / c_sb;
var x = utmX - 500000;
var y = isNorthHemisphere ? utmY : utmY - 10000000;
var s = ((zone * 6.0) - 183.0);
var lat = y / (6366197.724 * 0.9996); // Change c_sa for 6366197.724
var v = (c / Math.Pow(1 + (e2cuadrada * Math.Pow(Math.Cos(lat), 2)), 0.5)) * 0.9996;
var a = x / v;
var a1 = Math.Sin(2 * lat);
var a2 = a1 * Math.Pow((Math.Cos(lat)), 2);
var j2 = lat + (a1 / 2.0);
var j4 = ((3 * j2) + a2) / 4.0;
var j6 = (5 * j4 + a2 * Math.Pow((Math.Cos(lat)), 2)) / 3.0; // saque a2 de multiplicar por el coseno de lat y elevar al cuadrado
var alfa = (3.0 / 4.0) * e2cuadrada;
var beta = (5.0 / 3.0) * Math.Pow(alfa, 2);
var gama = (35.0 / 27.0) * Math.Pow(alfa, 3);
var bm = 0.9996 * c * (lat - alfa * j2 + beta * j4 - gama * j6);
var b = (y - bm) / v;
var epsi = ((e2cuadrada * Math.Pow(a, 2)) / 2.0) * Math.Pow((Math.Cos(lat)), 2);
var eps = a * (1 - (epsi / 3.0));
var nab = (b * (1 - epsi)) + lat;
var senoheps = (Math.Exp(eps) - Math.Exp(-eps)) / 2.0;
var delt = Math.Atan(senoheps / (Math.Cos(nab)));
var tao = Math.Atan(Math.Cos(delt) * Math.Tan(nab));
longitude = (delt / Math.PI) * 180 + s;
latitude = (((lat + (1 + e2cuadrada * Math.Pow(Math.Cos(lat), 2) - (3.0 / 2.0) * e2cuadrada * Math.Sin(lat) * Math.Cos(lat) * (tao - lat)) * (tao - lat))) / Math.PI) * 180; // era incorrecto el calculo
Console.WriteLine("Latitud: " + latitude.ToString() + "\nLongitud: " + longitude.ToString());
}
}
}
