I have some files in dig format which are simply maps with several
polygons within a circle. Each polygon has an attribute in a dig_att
file under the same name as the dig map. These attributes are integer codes
for a vegetation mix. I would like to rasterize these maps so that the
attributes become the category value in the raster map. Then I want to
reclassify the categories based on values in a lookup table.
I thought that when running v.to.rast I would end up with a raster
map with the categories taken from my attribute file, but the cat file
looks like this:
GRASS 4.0 > more 3c1981.0
# 373 categories0.00 0.00 0.00 0.00
0:no dataCan anyone outline the steps I need to take to get a raster file
with the correct category values. I have no labels for the categories
because the categories themselves are numerically important.Thanks,
________________________________________________________________
Doug Hersh Boston University Marine Program
dhersh@lupine.mbl.edu Marine Biological Laboratory
(508)548-3705 ext. 516 Woods Hole, MA 02543
Doug,
Unless I misunderstand your situation, the category VALUES of your raster map
should already agree with the attributes of the original vector map. The cats
file is a lookup table for when you have category LABELS. You can check this
situation by querying your raster map with d.what.rast, and then seeing if
the values agree with your original vector map.
You should be able to reclass this map in the manner that you desire. Write
back if I'm all wet, or simply misunderstand your problem. Good luck!
----------------
Malcolm D. Williamson - Technical Assistant E-mail: malcolm@cast.uark.edu
Center for Advanced Spatial Technologies Telephone: (501) 575-5736
Ozark Rm. 214 Fax: (501) 575-3846
University of Arkansas
Fayetteville, AR 72701