[MetaCRS] RE: Initial commit of CSV Test data files

[Norm Olsen]

Interesting point.  EPSG does specify latitude, longitude, and then height.  My experience says that many (if not most) coordinate system libraries use the longitude, latitude, height convention.  That is, 99.8% of the time and regardless of whether the coordinate system is projective or geographic, the first ordinate increases to the east, the second ordinate increases to the north, and the third ordinate increases away from the center of the earth.  I don't know what the default preference for Proj4 is, so I'd be interested in knowing of the opinions of the Proj4 folk on this.

Dogmatically, EPSG is correct.  Pragmatically, I believe longitude, latitude, and then height is correct. 

Norm

-----Original Message-----
From: Martin Desruisseaux [mailto:martin.desruisseaux at geomatys.fr] 
Sent: Monday, November 30, 2009 12:13 PM
To: Norm Olsen
Cc: Landon Blake; metacrs at lists.osgeo.org
Subject: Re: [MetaCRS] RE: Initial commit of CSV Test data files

Norm Olsen a écrit :
> Order of the ordinates in the test data fields (source, target, tolerance) MUST match the respective coordinate system definitions; whatever that order is.  99% of the time, that does mean X, Y, and the Z; and 98% of the time longitude, latitude, and then height.

You mean (latitude, longitude, height) (at least in the case of EPSG codes)?

	Martin