[geos-devel] Dimension of EMPTY geoms

[strk at refractions.net]

On Mon, Dec 04, 2006 at 04:01:16PM +0100, Mateusz Loskot wrote:
> Markus Schaber wrote:
> > Hi, Mateusz,
> > 
> > Mateusz Loskot wrote:
> >> AFAIK OGC SFS does say nothing about how to report dimension of empty
> >> geometry.
> >>
> >> OGC SFS reserves values 0, 1, and 2 for dimensions of non-empty
> >> geometry, so I'd suggest to use negative value.
> > 
> > Don't confuse OGC dimension (geometrical dimensionality of the described
> > object, Points have 0, LineStrings have 1, and Polygons have 2) and
> > coordinate dimension (number of ordinates per vertex, which can be 2,3
> > or 4 in PostGIS).
> 
> Markus,
> 
> You are perfectly right! Sorry, I've read the message too fast.

No no...  Mateus was right !
Unless I've read the bug report too fast myself :)
We're talking about OGC dimension, not coordinate dimension here.

Using negative value will be not comfortable as we're using
-1 to represent an exception.

--strk;