Hank Hatch Says:

November 3rd, 2008 at 11:46 am
Also it is more of a direct wrap to do it like this ->

private StateMachineEventHandler canTransition;
public event StateMachineEventHandler CanTranistion
{
add { this.canTransition += value; }
remove { this.canTransition -= value; }
}

which is pretty darn simple considering the power it can give you.

Just wanted to say thanks for ur c# implementation of Vincenty’s formula,

cheers,
steve

Thanks so much for sharing this brilliant code, it has proved invaluable to me in several projects.
I would like to propose a small change which made the code more robust for real applications:
The function GeodeticCalculator.calculateEndingGlobalCoordinates(…) goes into an infinite loop if its distance parameter is given as 0.
I added these lines to the beginning of the function:

if (distance == 0)
{
return new GlobalCoordinates(start.getLatitude(), start.getLongitude());
}

Thanks again
Aharon

rick

The reason is because the shortest path between two points at the same latitude doesn’t follow the latitudinal line (unless you’re on the equator). If you’re not on the equator, the shortest path will bow out toward the nearest pole.

Try GlobalPosition(45, 100, 0.0) and GlobalPosition(45, 101, 0.0). Because these points are very close, the azimuth is 89.65 (very nearly 90).

Now, try GlobalPosition(45, 100, 0.0) and GlobalPosition(45, -75, 0.0). These two points are on nearly opposite sides. The azimuth is 3.53. In order words, the shortest path takes you right by the north pole.

Make sense?

–Mike

However, the azimuth returned was not 90 degrees as I expected, but about 75 degrees. As I change the longitude, I get different angles for the azimuth. Maybe I don’t understand this correctly, but the answer seems counter-intuitive. Could someone explain?

thanks

rick