You can not select more than 25 topics
Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
44 lines
1.2 KiB
44 lines
1.2 KiB
using System;
|
|
|
|
namespace POCDistance.Util
|
|
{
|
|
public static class CalculateDistance
|
|
{
|
|
static double toRadians(
|
|
double angleIn10thofaDegree)
|
|
{
|
|
// Angle in 10th
|
|
// of a degree
|
|
return (angleIn10thofaDegree * Math.PI) / 180;
|
|
}
|
|
public static double GetDistance(double lat1, double lon1, double lat2, double lon2)
|
|
{
|
|
|
|
// The math module contains
|
|
// a function named toRadians
|
|
// which converts from degrees
|
|
// to radians.
|
|
lon1 = toRadians(lon1);
|
|
lon2 = toRadians(lon2);
|
|
lat1 = toRadians(lat1);
|
|
lat2 = toRadians(lat2);
|
|
|
|
// Haversine formula
|
|
double dlon = lon2 - lon1;
|
|
double dlat = lat2 - lat1;
|
|
double a = Math.Pow(Math.Sin(dlat / 2), 2) +
|
|
Math.Cos(lat1) * Math.Cos(lat2) *
|
|
Math.Pow(Math.Sin(dlon / 2), 2);
|
|
|
|
double c = 2 * Math.Asin(Math.Sqrt(a));
|
|
|
|
// Radius of earth in
|
|
// kilometers. Use 3956
|
|
// for miles
|
|
double r = 6371;
|
|
|
|
// calculate the result
|
|
return (c * r);
|
|
}
|
|
}
|
|
}
|