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I have been struggling for quite some time trying to make a land use vector map out of two separate vector maps. One is water and the other is vegetation. Both only contain areas, and those areas which are active are set to a single category value (1 for water, 2 for vegetation). Islands are valid areas with no category id. I have tried the following two approaches<BR>
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<I>v.patch input=water,vegetation out=landuse</I><BR>
<I>v.overlay ainput=water atype=area binput=vegetation btype=area output=landuse operator=or</I><BR>
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to no avail. The results is always something bizarre that I haven't quite figured out the meaning of. Certainly not what one would expect. Both maps appear to be topographically correct. I have uploaded a tar.bz2 of the project file <A HREF="http://eddie.alcazarmountain.com/kootenay.tar.bz2">here</A>. I removed all the other map files leaving only the two vector maps and a region setting. It is only about six megabytes. I am running {GRASS 6.2.1 (2006)} on {Linux spica 2.6.23-gentoo-r6 #1 Mon Jan 28 11:06:48 MST 2008 x86_64 Mobile AMD Athlon(tm) 64 Processor 3000+ AuthenticAMD GNU/Linux}.<BR>
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-- <BR>
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<I><FONT SIZE="2">Eddie</FONT></I><BR>
<I><FONT SIZE="2"><A HREF="mailto:eddie@mailforce.net">eddie@mailforce.net</A></FONT></I>
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