Comments for Talk Nerdy To Me - Java, C#, .Net http://www.gavaghan.org/blog Mike Gavaghan blogs on Java, C#, .Net, and the software industry Wed, 10 Mar 2010 13:34:01 +0000 http://wordpress.org/?v=2.1.3 Comment on Java, GPS Receivers, and Geocaching: Vincenty’s Formula by Michael http://www.gavaghan.org/blog/2007/11/16/java-gps-receivers-and-geocaching-vincentys-formula/#comment-254 Michael Tue, 16 Feb 2010 20:04:25 +0000 http://www.gavaghan.org/blog/2007/11/16/java-gps-receivers-and-geocaching-vincentys-formula/#comment-254 I tried the GeodeticCalculator for use with Nasa's open source WorldWindJava and after a quick set of tests that converted WorldWind Java's LatLon, Position and Angle to the correct input required by the GeodeticCalculator the results were very accurate. I tried the GeodeticCalculator for use with Nasa’s open source WorldWindJava and after a quick set of tests that converted WorldWind Java’s LatLon, Position and Angle to the correct input required by the GeodeticCalculator the results were very accurate.

]]> Comment on C#, GPS Receivers, and Geocaching: Vincenty’s Formula by Markus http://www.gavaghan.org/blog/2007/08/06/c-gps-receivers-and-geocaching-vincentys-formula/#comment-247 Markus Thu, 21 Jan 2010 04:42:21 +0000 http://www.gavaghan.org/blog/2007/08/06/c-gps-receivers-and-geocaching-vincentys-formula/#comment-247 Hello Mike, 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 :o) 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 Hello Mike,

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 :o)

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

]]> Comment on C#, GPS Receivers, and Geocaching: Vincenty’s Formula by Daniel http://www.gavaghan.org/blog/2007/08/06/c-gps-receivers-and-geocaching-vincentys-formula/#comment-246 Daniel Thu, 14 Jan 2010 10:38:03 +0000 http://www.gavaghan.org/blog/2007/08/06/c-gps-receivers-and-geocaching-vincentys-formula/#comment-246 Hi Mike, Thanks for sharing this. It is a great help and timesaver for my little freeware project: Generation of airspace boundaries to be uploaded to an Variometer/GPS unit for Paraglider and Hanglider pilots. Many thanks & Regards from Switzerland Daniel Hi Mike,
Thanks for sharing this. It is a great help and timesaver for my little freeware project: Generation of airspace boundaries to be uploaded to an Variometer/GPS unit for Paraglider and Hanglider pilots.
Many thanks & Regards from Switzerland
Daniel

]]> Comment on C#, GPS Receivers, and Geocaching: Vincenty’s Formula by ramesh http://www.gavaghan.org/blog/2007/08/06/c-gps-receivers-and-geocaching-vincentys-formula/#comment-243 ramesh Wed, 11 Nov 2009 17:12:26 +0000 http://www.gavaghan.org/blog/2007/08/06/c-gps-receivers-and-geocaching-vincentys-formula/#comment-243 excellent stuff for beginners... Thanks a lot... excellent stuff for beginners… Thanks a lot…

]]> Comment on Java, GPS Receivers, and Geocaching: Vincenty’s Formula by Jacky http://www.gavaghan.org/blog/2007/11/16/java-gps-receivers-and-geocaching-vincentys-formula/#comment-234 Jacky Fri, 02 Oct 2009 07:10:10 +0000 http://www.gavaghan.org/blog/2007/11/16/java-gps-receivers-and-geocaching-vincentys-formula/#comment-234 This API is awesome. Very useful for me. Can I include this API in my system? Does any license I need follow? This API is awesome. Very useful for me. Can I include this API in my system? Does any license I need follow?

]]> Comment on Java, GPS Receivers, and Geocaching: Vincenty’s Formula by Peter http://www.gavaghan.org/blog/2007/11/16/java-gps-receivers-and-geocaching-vincentys-formula/#comment-231 Peter Thu, 20 Aug 2009 14:38:06 +0000 http://www.gavaghan.org/blog/2007/11/16/java-gps-receivers-and-geocaching-vincentys-formula/#comment-231 Can I use this code to add a certain distance to a coordinate? So calculating a coordinate that is e.g. 100miles north of a given coordinate? Can I use this code to add a certain distance to a coordinate? So calculating a coordinate that is e.g. 100miles north of a given coordinate?

]]> Comment on NHibernate in a Medium Trust Environment by dev http://www.gavaghan.org/blog/2007/08/21/nhibernate-in-a-medium-trust-environment/#comment-230 dev Sat, 04 Jul 2009 04:08:59 +0000 http://www.gavaghan.org/blog/2007/08/21/nhibernate-in-a-medium-trust-environment/#comment-230 To use NH in Medium Trust use Proxy Generators (of NHContrib) http://nhforge.org/wikis/proxygenerators10/introduction.aspx To use NH in Medium Trust use Proxy Generators (of NHContrib)
http://nhforge.org/wikis/proxygenerators10/introduction.aspx

]]> Comment on C#, GPS Receivers, and Geocaching: Vincenty’s Formula by Stephen http://www.gavaghan.org/blog/2007/08/06/c-gps-receivers-and-geocaching-vincentys-formula/#comment-228 Stephen Sat, 06 Jun 2009 17:50:25 +0000 http://www.gavaghan.org/blog/2007/08/06/c-gps-receivers-and-geocaching-vincentys-formula/#comment-228 Hi Mike - this looks like a great implementation, with excellent documentation. I'm looking to incorporate some inverse 3D geodetic calcs into a sunrise/sunset type app for photographers. Specifically, I need to be able to calculate the elevation angle (or altitude - I think there's a subtle difference depending on if you're an astronomer or a surveyor, but I don't know what it is...) between two points. 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 Hi Mike - this looks like a great implementation, with excellent documentation. I’m looking to incorporate some inverse 3D geodetic calcs into a sunrise/sunset type app for photographers. Specifically, I need to be able to calculate the elevation angle (or altitude - I think there’s a subtle difference depending on if you’re an astronomer or a surveyor, but I don’t know what it is…) between two points.

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

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