[postgis-users] return boundary

[Burgholzer,Robert]

So,
Do you need to iterate through the sub-polygons in your multi and get a
boundary of each?

r.b.

Robert W. Burgholzer
Surface Water Modeler
Office of Water Supply and Planning
Virginia Department of Environmental Quality
rwburgholzer at deq.virginia.gov
804-698-4405
Open Source Modeling Tools:
http://sourceforge.net/projects/npsource/

-----Original Message-----
From: postgis-users-bounces at postgis.refractions.net
[mailto:postgis-users-bounces at postgis.refractions.net] On Behalf Of
Travis Kirstine
Sent: Friday, November 21, 2008 10:51 AM
To: PostGIS Users Discussion
Subject: Re: [postgis-users] return boundary

Thanks Obe
But I'm looking for something that returns the boundary of all the
selected features combined and attached.  Something that has the
abilty to take the group the features together like convex hull but
keep the detail of the of the edge like boundary.

2008/11/21 Obe, Regina <robe.dnd at cityofboston.gov>:
> How about ST_Boundary?
>
http://postgis.refractions.net/documentation/manual-svn/ST_Boundary.html
>
> -----Original Message-----
> From: postgis-users-bounces at postgis.refractions.net
> [mailto:postgis-users-bounces at postgis.refractions.net] On Behalf Of
> Travis Kirstine
> Sent: Friday, November 21, 2008 10:18 AM
> To: PostGIS Users Discussion
> Subject: [postgis-users] return boundary
>
> I have a multipolygon that has consists mainland and island polygons.
> I need to generate a single polygon / line that represent the boundary
> of the multipolygon as a whole, something like a convex hull but
> keeping the detail of the outer rings and joining the islands to the
> mainland.  I have been try different combos of convex hull, buffer and
> difference but can't get what I'm looking for.
>
> Any thoughts would be greatly appreciated
>
> Regards
>
> --
> Travis K.
>
> Toronto, Canada
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> "She knows there's no success like failure
> And that failure's no success at all."
> -Bob Dylan-
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-- 
Travis K.

Toronto, Canada
------------------------------------------------------------
"She knows there's no success like failure
And that failure's no success at all."
-Bob Dylan-
------------------------------------------------------------
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