Merging Regions of a shapefile

[Schuyler Erle]

* On 16-Jan-2006 at 12:40PM PST, Neil Saunders said:
> 
> Thanks for your reply; However I've tried using PostGIS but could't
> get the shapes to actually "merge" together. Ideally what I'd like to
> do is have a tool such as OpenEV in to which I could load my
> shapefile, select a given number of *adjacent* regions, and merge
> selected regions to a single region, if you catch my drift. I'm
> beginning to think that it may not be possible... :(

You can totally do this in GRASS, if you have the patience to learn
GRASS. We describe how in hack #77 from Mapping Hacks
(http://www.mappinghacks.com/).

If you have a recent PostGIS built with a recent GEOS, you might try
the BuildArea() function from GEOS:

    http://postgis.refractions.net/docs/ch06.html#BuildArea

SDE