[GRASS-user] Vectorise a raster file

[Hamish]

> I created a raster with the visiblity function, and I wanted to
> vectorise it.  I used v.to.vect but the result it is not good because
> there are holes in  area that are fill by color (and have to be
> empty). I try to use mapcalc to  remove all bad area, i try to remove
> it by db.execute but, if I list value, I  have for all item value=1
> but if I try to display the vector using this sql  statement :
> value=1, the vector is correctly displaying ! If I export it in  shp
> the vector is not correct !

This is a feature. d.vect by itself fills holes as well. If you only
want to show areas with data use "d.vect cats=1-999999".



Hamish