I'm facing a problem using the v.what.rast comand.
I'm trying to update the vector "canali" which represents some streams, with the slope value for every single point of the lines. The slope values are contained in the raster map "Pendenza".
I then created a column by entering:
v.db.addcol canali column='slope integer'
and that works fine: it creates an empty column named "slope".
Then I run the command line:
v.what.rast vector=canali@PERMANENT raster=Pendenza@PERMANENT column=slope
but it tells me the following:
No record for category 0 in table 1250 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
Anyone out there can help me? I'm new to Grass and I don't want to give up!