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

Thanks for sharing your information. I found it very intriguing, but too much for my simple question. I was wondering if you could shed some light on my problem.

I need to generate a bounding box of min and max latitude and longitude values so I can return addresses within a given radius.

I have two func’s below to return the range I need to +/- to the lon lat coordinates to establish the bounding box. However I don’t think the math is 100%

I am using the Haversine formula to generate my distance calculations and that seems to be working accurately. I investigated the Vincenty formula for distance as well but for my needs that was overkill.

My problem is that I would like my search results to be as accurate as Haversine in that the range I +/- to the lon lat coordinates takes into account the ellipsoidal curvature or the earth.

Ok, here are my func’s…please note I am not a Math professor )

static Func GetLatitudeRange = (latitude, distance) => (180.0 / Math.PI) * (distance / EARTH_RADIUS_IN_KM);

static Func GetLongitudeRange = (longitude, latitude, distance) =>
(
Math.Asin(
Math.Sin(distance / EARTH_RADIUS_IN_KM) / Math.Cos(latitude)
)
);

Many Thanks,
Markus

Taking your Pike’s Peak example in the source code, if you were standing on the plane east of Pike’s Peak and wanted to determine when the run might set behind it, I need the elevation angle between the two points.

My question is: is it possible to use your implementation to return the zenith distance from which elevation angle/altitude can be derived? I can see the ElevationChange, but am unsure how I’d get to an accurate angle from this.

Some examples of the problem I mean here: http://photo.net/nature-photography-forum/00SigL (about half way down the page) and here http://www.ngs.noaa.gov/cgi-bin/Inv_Fwd/invers3d.prl.

Many thanks for making this code available.

Stephen