[GRASS-user] the area of a polygon?

[Martin Wegmann]

On Dienstag, 11. März 2008 16:35:36 Corrado wrote:
> Dear friends,
>
> 1) v.report does not allow for selecting only one polygon in a map with
> many polygons.
>
> 2) the query button returns the length of the boundary, but not the area.
>
> 3) v.to.db does not allow for selecting only one polygon.
>
> Am I doing something wrong?

perhaps this helps:

r.to.vect input= output=out feature=area
v.db.addcol map=out layer=1 'columns=area double' 
v.to.db map=out type=point,line,boundary,centroid layer=1 qlayer=1 option=area 
units=meters column=area 
v.to.rast out output=out_area use=attr col=area --o

> On Tuesday 11 March 2008 15:07:30 Corrado wrote:
> > Dear friends,
> >
> > how do you measure the area of a polygon in grass?
> >
> > Best Regards
>
> Best Regards



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University of Wuerzburg
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