[GRASS-user] How to change vector category values?

[Markus Neteler]

On Wed, Nov 21, 2012 at 1:40 PM, Thomas Adams - NOAA Federal
<thomas.adams at noaa.gov> wrote:
> List:
>
> I have 31 river basins (vector areas) with randomly assigned cat values; I
> would like to assign the cat values to something more meaningful to me,
> namely, I want the cat values to reflect upstream to downstream
> computational order when modeling. How do I re-assign the cat values?

You may use:
http://grass.osgeo.org/grass64/manuals/v.category.html
and/or
http://grass.osgeo.org/grass64/manuals/v.edit.html

tool=string
   ...
    catadd: Set new categories to selected vector features for defined layer
    catdel: Delete categories from selected vector features for defined layer

Hope this helps
Markus