[GRASS-user] How does v.category work?

On Tue, 2008-11-11 at 03:11 +0100, Nikos Alexandris wrote:

I face (I think) the problem described by Christian in this thread

(last

post).
http://www.nabble.com/Reorg-cat-entry--td18505187.html#a18507936

# I want to upload some raster values (using v.what.rast) in my
fgaps_centroids map.
# The "cat" of the "fgaps_cwntroids" map starts with the value "2",

thus

the upload fails
# attempting to upload
v.what.rast fgaps_centroids raster=elevation_m column=z

WARNING: Raster type is integer and column type is float
WARNING: No record for category 0 in table
         <fgaps_shadows_nik_copy_centroid>
7284 categories loaded from table
1 categories loaded from vector
1 categories from vector missing in table
0 duplicate categories in vector
0 records updated
0 update errors

# trying to re-assign categories in fgaps_centroids
v.category in=fgaps out=fgaps_DEL option=del
## The output map is identical with the input.
## So repeating v.category with "option=add" doesn't make anything
## The output map with option=del as well as with option=add start

with

cat=2 !?

I read the manual, all possible post I found in the archive but it
doesn't make any sense why it doesn't work.

Any suggestions?

Kind regards, Nikos

The only thing I could do was to remove link between map and table
(v.db.connect -d), export the table (using sqlitebrowser) as .csv, edit
in Gnumeric, import back, re-connect (v.db.connect) map with edited
table.

It's not the "correct" solution I guess... but I tried everything else
and nothing worked (v.category, v.reclass, v.to.db).