[GRASSLIST:7705] Re: area 3d

[Carlos Guâno Grohmann]

Ivan, 

You can get the real (3D) area of each cell in your DTM using
r.mapcalc and a slope map (take a look at Grohmann, 2004, Computers &
Geosciences 30, i'll send you the pdf in a separate mail), and then
sum the values.

Carlos




On 7/25/05, ivan marchesini <marchesini at unipg.it> wrote:
> dear users,
> I'm trying to obtain the  3d surface of a dtm using r.surf.area...
> the problem is that the area doesn't cover all the region and the
> boundaries are really irregular...
> in this conditions the module r.surf.area finds problems and I obtain a
> 3d surface smaller than the flat surface.
> I have tried to increase the resolution but I have only obtained a small
> increse of the 3d area....
> any suggestion for solving the problem????
> thank you for your help...
> ivan
> 
> 
> 
> 
> 
> --
> Ivan Marchesini
> Department of Civil and Environmental Engineering
> University of Perugia
> Via G. Duranti 93/a
> 06125
> Perugia (Italy)
> e-mail: marchesini at unipg.it
>         ivan.marchesini at gmail.com
> tel: +39(0)755853760
> fax: +39(0)755853756
> 
> 
> 
> 
> 


-- 
+-----------------------------------------------------------+
              Carlos Henrique Grohmann - Guano   
  Geologist M.Sc  - Doctorate Student at IGc-USP - Brazil
Linux User #89721  - carlos dot grohmann at gmail dot com
+-----------------------------------------------------------+