/// <summary>
/// Calculates geo-spatial distance between two locations.
/// </summary>
/// <param name="lat1">
/// The initial location latitude degrees.
/// </param>
/// <param name="lon1">
/// The initial location longitude degrees.
/// </param>
/// <param name="lat2">
/// The target location latitude degrees.
/// </param>
/// <param name="lon2">
/// The target location longitude degrees.
/// </param>
/// <param name="unit">
/// The desired distance measurement unit.
/// </param>
public static double GetDistance(
double lat1,
double lon1,
double lat2,
double lon2,
GeoSpatialDistanceUnit unit = GeoSpatialDistanceUnit.NauticalMile)
{
double theta = lon1 - lon2;
double dist =
Math.Sin(DegreesToRadians(lat1)) * Math.Sin(DegreesToRadians(lat2))
+ Math.Cos(DegreesToRadians(lat1)) * Math.Cos(DegreesToRadians(lat2)) * Math.Cos(DegreesToRadians(theta));
dist = Math.Acos(dist);
dist = RadiansToDegrees(dist);
dist =
dist *
Constants.MinutesInDegree *
Constants.StatuteMilesInNauticalMile;
if (unit == GeoSpatialDistanceUnit.Kilometer)
{
dist = dist * Constants.KilometersInMile;
}
else if (unit == GeoSpatialDistanceUnit.NauticalMile)
{
dist = dist * Constants.NauticalMilesInMile;
}
return(dist);
}
/// <summary>
/// Calculates geo-spatial distance between two locations.
/// </summary>
/// <param name="p1">The first point.</param>
/// <param name="p2">The second point.</param>
/// <param name="unit">
/// The desired distance measurement unit.
/// </param>
public static double GetDistance(
GeoSpatialPoint p1,
GeoSpatialPoint p2,
GeoSpatialDistanceUnit unit = GeoSpatialDistanceUnit.NauticalMile)
{
return(GetDistance(
p1.Latitude,
p1.Longitude,
p2.Latitude,
p2.Longitude,
unit));
}
