[GRASSLIST:311] Re: How to satisfy some constraints

[Jachym Cepicky]

hallo,
sorry for only short comment, but you could try to work with rasters and
firction surfaces (see r.cost, r.walk and r.drain for details)

jachym

On Wed, Mar 22, 2006 at 11:18:20AM +0000, giglio.antonio at katamail.com wrote:
> Hi folks,
> starting from some maps* I have, I should be able to find one or more
> paths that satisfy the sequent constraints:
> - path must be in 500m from a road for every x km;
> - path must start from a lake at least y sqkm large;
> - path must arrive in at least z villages populated area;
> - path must be always going-down;
> - path must be the shortest one (or the first 10 paths).
> 
> x, y and z are 3 variables not yet decided and can be disregarded, because
> I'm interested mostly to how-to-work.
> 
> *maps I have are:
> - roads map;
> - DEM;
> - lakes map;
> - villages map.
> 
> I did something similar, calculating areas that satisfy more simple constrains,
> as distances constraints, so I had to do only buffers (r.buffer), and, after
> selecting areas (assigning 1 to the proper points and 0 to the others with r.reclass),
> to calculate the interesting areas (using r.mapcalc: wanted_map=reclassed_buffered_map_1 *
> reclassed_buffered_map_2 * reclassed_buffered_map_3....).
> Currently, I'm not able to realize HOW I could do to calculate what I need.
> Thank you,
> Antonio Giglio.
> 
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-- 
Jachym Cepicky                                  
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