Diffs between raster/vector polygon #'s

Tom Orth orth at skyler.arc.ab.ca
Wed Sep 6 08:00:00 EDT 1995

I posted a variation of this question to the user group a while ago but thought
I might get more information here 8-)

We create an overlay with r.cross which is then converted to a vector using
r.poly.  We perform some data-processing on the raster overlay, which we would
then like to incorporate into Arc/Info (basically, we modify the information 
associated with each polygon in the map). Unfortunately, it seems that the vect
data (required by Arc/Info) has a different polygon count (about 50% more) than
the raster data.

My questions, in no particular order, are:

        1) Why is it doing this ?
        2) Can I avoid this behavior ? (ie. make them have the same # polygons)

I've been playing with this off and on, as I don't really have the time to go
source code digging (unless I have to 8-(

Thanks !


Thomas Orth, M.Sc.                              Alberta Research Council
Research Officer                                3rd Floor, 6815 8th Street N.E.
Advanced Computing & Engineering                Calgary, Alberta T2E 7H7       
Spatial Information Management and Analysis     Canada                         
Email:              Phone:             Fax:                WWW:                
orth at arc.ab.ca      (403) 297-7571     (403) 297-2339      http://www.arc.ab.ca
    I'd be really surprised if my opinions reflected those of my employers.    

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