[GRASS-user] r.param.scale Incorrect Output

Dylan Beaudette debeaudette at ucdavis.edu
Thu Jan 28 18:50:41 EST 2010


On Thursday 28 January 2010, Rich Shepard wrote:
> On Thu, 28 Jan 2010, Rich Shepard wrote:
> >  I'm stymied trying to get output from r.param.scale that is equivalent
> > to the example on the bottom of the man page.
>
>    Resetting g.region to the input elevation map without any additional
> options and adding a zmult factor of 5 appears to help. When the specified
> param is 'features' I see what should be ridges and channels, but no peaks
> or pits.
>
>    Changing the calculated param to either elev or profc yields blank maps
> when I try to display them with d.rast.
>
>    Suggestions on how to properly apply this module will be very helpful.
>
> Rich
> _______________________________________________

Hi,

Are you working with data in a projected coordinate system? Are you x,y and z 
coordinates all in the same units. What is the general nature of the terrain 
you are looking at? Try adjusting the window size to get generalized 
features-- remember that the quantification of terrain is a fractal problem.

Cheers,
Dylan


-- 
Dylan Beaudette
Soil Resource Laboratory
http://casoilresource.lawr.ucdavis.edu/
University of California at Davis
530.754.7341


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