[postgis-users] How to tell if 2 geometries are spatially equal

[Martin Davis]

Andy Anderson wrote:
>
> I'll also note that, to be consistent, this must also mean that 
> MULTIPOLYGON((0 0, 5 5, 5 0, 0 0), (0 0, 0 5, 5 5, 0 0)) doesn't have 
> a boundary line at LINESTRING(0 0, 5 5).
Well, that Multipolygon is actually invalid - since MPs can't have 
coincident line segments. So the definition *is* consistent!
>
> I'm not sure which one that is.
It's the OGC document 99-049 (the first one you sent)

-- 
Martin Davis
Senior Technical Architect
Refractions Research, Inc.
(250) 383-3022