Greetings,
in some experiments with r.to.vect in the mac os X version of GRASS 6.1-CVS i have found that:
r.to.vect -s -v in=raster out=vector
echo "select * from vector" | db.select
cat|label
1.000000|
2.000000|
3.000000|
4.000000|
5.000000|
... looks like the cat column is not of type INT, when the input raster was. this causes problems later on when trying to use v.extract:
v.extract in=vector out=test2 where="cat = 2"
Load cats from the database (table = sc_vect_small_c1, db = /Users/dylan1/grassdata/pinn/premap/dbf/).
1 cats loaded from the database
Building topology ...
158 primitives registered
Building areas: 100%
65 areas built
64 isles built
Attaching islands: 100%
Attaching centroids: 100%
Topology was built.
Number of nodes : 157
Number of primitives: 158
Number of points : 0
Number of lines : 0
Number of boundaries: 135
Number of centroids : 23
Number of areas : 65
Number of isles : 64
Number of areas without centroid : 42
Writing attributes ...
Layer 1
ERROR: Column 'cat' is not integer
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
the resulting vector will display, but its topology broken...
any ideas?
--
Dylan Beaudette
Soils and Biogeochemistry Graduate Group
University of California at Davis
530.754.7341