Latitude-Longitude Ordering

SQL Server 2008 WKT X/Y Switching Illustrated « GeoMusings

SQL Server 2008 WKT X/Y Switching Illustrated « GeoMusings — Fri, 28 Dec 2007 01:12:54 GMT

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SharpGIS — Fri, 28 Dec 2007 03:33:52 GMT

re: Latitude-Longitude Ordering

Paul Ramsey — Fri, 28 Dec 2007 07:57:51 GMT

Isaac, that's fabulous, kudos for making the difficult decision to change the behavior on a product already (somewhat) released (hooray for beta releases).

"What's wrong?"

"I felt a great disturbance in the Force, as if millions of #ifdefs cried out in terror and were suddenly silenced. I fear something terrible has happened."

re: Latitude-Longitude Ordering

Bill Dollins — Fri, 28 Dec 2007 19:17:32 GMT

Isaac,

Great news! I know the debate raged (and will continue to) but I'm glad that the implementation will be consistent. It's never easy to go back and change such an implementation so I want to commend you for reconsidering it.

re: Latitude-Longitude Ordering

John Davidson — Mon, 31 Dec 2007 18:51:35 GMT

What's "usable" for some (in this case programmers who don't want to worry about the details and the implications) can literally kill others. Think of people in vehicles moving at high velocity on or over terrain where some data come from systems with coords in x,y order and other data come from systems with coords in y,x order. Not too far-fetched.

Standards are what make systems and data usable. Adopting industry standards (and they do exist!) that define unambiguous semantics and prescribe proper usage give you firm ground to argue usability.

See specs from OGC (http://www.opengeospatial.org/standards/common, http://www.opengeospatial.org/standards/wms, http://portal.opengeospatial.org/files/?artifact_id=6716), GeoRSS (http://georss.org/model), and EPSG (http://www.epsg.org/Geodetic.html) for examples.

re: Latitude-Longitude Ordering

isaac — Mon, 31 Dec 2007 19:46:21 GMT

Hi John,

This was my initial reaction. Really, if you look just about anywhere other than how people use WKT and WKB you find latitude-longitude ordering. I would argue that with any new format we ought use lat-long.

But, when you look at it, this is really just a formatting issue, and while there is no clear official standard indicating any particular ordering for WKT and WKB, the de facto standard seems, perhaps unfortunately, to be long-lat.

Cheers,

-Isaac

re: Latitude-Longitude Ordering

Morten — Mon, 21 Jan 2008 22:29:21 GMT

Isaac: I wouldn't agree. There is a big difference between how we >store< stuff, and how we >display< stuff. Think of dates. They are stored as number of ticks, and it is then up to the developer to decide on a proper input/output format that he will present to the user.

So as John say, long/lat is usuable for programmers, and guess what... only programmers will be the ones to worry about this, and they are ultimately the ones who control what string representaion of a point will look like on a screen. If we should really go with the analogy if storing data as we present them, why don't we store it in Degree-minutes-seconds with a N/S E/W prefix?

Honestly I think any kind of internal datastructure should store longitude before latitude. Why? Because it's consistent with how we also store planar coordinates (and yes I do think they can be compared in several ways).

But kudos for at least changing it for WKT/B.

New Spatial Features in the SQL Server 2008 February CTP

Ed on Spatial — Fri, 29 Feb 2008 07:50:53 GMT

Now that the February CTP (CTP-6) for SQL Server 2008 is available , it's time to let folks know what

re: Latitude-Longitude Ordering

adamw-manifold — Wed, 05 Mar 2008 17:19:18 GMT

Could you please elaborate on what it is you are planning to do with regards to latitude / longitude ordering for the CTP following CTP-6?

I have been through the forum thread you link to and through the CTP-6 post by Ed, and I am still not sure what exactly the change is going to be. Is it that you will switch the WKB and WKT representations for the GEOGRAPHY type to use XY ordering? Is it something else? Or is it all still up in the air?

Thanks.

The Upcoming Geography Coordinate Order Swap---A FAQ

Isaac @ MSDN — Thu, 06 Mar 2008 00:37:13 GMT

Hi Folks, I just thought I'd take a few moments clarify the upcoming coordinate order swap for the geography

re: Latitude-Longitude Ordering

artlembo — Wed, 12 Mar 2008 04:18:00 GMT

Isaac,

this is good news. In Manifold, I was able to create an SQL loader:

select "insert into ithparc2 (gid,geometry) values (" & id & ", geography::STGeomFromText('" & cstr(cgeomwkb([Geom (I)])) & "',4326));" from [Parcels]

this creates thousands of lines of INSERT statements really nicely. However, converting a Manifold geometry to WKB and then to WKT see the line - CSTR(CGEOMWKB([Geom (I)]) -

creates the coordinates in reverse order.

I'll look forward to the next CTP update.

GETTING YOUR PROGRAMS READY FOR THE UPCOMING GEOGRAPHY COORDINATE ORDER SWAP

Spatial Ed — Mon, 24 Mar 2008 18:48:19 GMT

For those of you who have programs which work with November CTP (CTP-5) and February CTP (CTP-6) and

Our Upcoming Builder API

Isaac @ MSDN — Sat, 31 May 2008 02:40:31 GMT

Hi Folks, We have one more upcoming pre-release before we're done with SQL Server 2008, and while I've

RC0 is Out: Spatial Notes

Isaac @ MSDN — Tue, 10 Jun 2008 17:22:51 GMT

Hi Folks, As we continue to shut down SQL Server 2008, our first release candidate has been released

Connecting With Connect

Isaac @ MSDN — Fri, 15 Aug 2008 18:18:18 GMT

Hi Folks, This post is motivated by some recent discussion I've seen in the various tubes .  I don't

re: Latitude-Longitude Ordering

Andrej — Mon, 05 Jan 2009 20:55:13 GMT

It's incredible.

All my life from birthday till the present days i've thought what we must store points in the order of axis of the coordinate system this point is assigned to.

There are different coordinate systems: some use lat/lon order, but there are few ones, that use lon/lat order.