[udig-devel] intersection/disjunction of layers?

[Leigh Fitzgibbon]

One way would be to create a third view which is the INNER JOIN of the other
two on road segment id and then drag that from the Catalog onto the map. 

Cheers,
Leigh

-----Original Message-----
From: udig-devel-bounces at lists.refractions.net
[mailto:udig-devel-bounces at lists.refractions.net] On Behalf Of Vince Darley
Sent: Wednesday, 12 December 2007 10:27 PM
To: User-friendly Desktop Internet GIS
Subject: [udig-devel] intersection/disjunction of layers?

I have several layers related to a road network.  Each is composed of 
LineStrings or similar.  These layers are all different views/subsets 
of an underlying postgres table of road segments -- all referenced by 
a primary "road segment id" key.

I'm wondering if uDig (or any community plugins) provide an easy way 
to see, for any pair of such layers, which road segments are shared 
by the two layers and which are not shared - i.e. intersection and 
disjunction of the sets of road segments.

Any known capabilities which cover this?

regards,

Vince.

_______________________________________________
User-friendly Desktop Internet GIS (uDig)
http://udig.refractions.net
http://lists.refractions.net/mailman/listinfo/udig-devel

No virus found in this incoming message.
Checked by AVG Free Edition. 
Version: 7.5.503 / Virus Database: 269.16.17/1179 - Release Date: 9/12/2007
11:06 AM
 

No virus found in this outgoing message.
Checked by AVG Free Edition. 
Version: 7.5.503 / Virus Database: 269.16.17/1179 - Release Date: 9/12/2007
11:06 AM