[GRASSLIST:4450] RE:Two questions: 1. r.param.scale; usage and etc... an error got into my last post!!

Thomas Dewez Thomas.Dewez at brunel.ac.uk
Tue Sep 10 02:58:20 EDT 2002


Lars,

I have been messing around with r.param.scale just recently and found the
following. You can obtain more spatially extended classes if you play with
the curvature tolerance. In my case, lowering the default c_tol value to
0.001 improved the output image nicely. Is it meangingfull to do this ? I
don't know, I have not used those results yet hoping that somebody would
comment on them first. Perhaps Jo Wood would like to answer this.

I don't know for your second question
Hope this helps

Thomas

 On Mon, 9 Sep 2002, Lars Forseth wrote:

> Hi! Hav to repost due to an error that sneaked into my first post; sorry for 
> the inconvenience!
> 
> I have just - this weekend - installed GRASS5.0.0; on my SuSE 7.3 box. only 
> problem was with NVIZ and libtcl.so.0 ; "ln libtcl.so libtcl.so.0" solved 
> that. Congratulations to the GRASS team, well done :-)
> 
> So my questions;
> 1. In their book "Open source GIS" Neteler&Mitasova on page 114 gives an 
> example of the usage of r.param.scale. This gives - with Spearfish data 
> (elevation.dem) - not a very meaningfull result. Sent to a monitor the 
> resulting datasett gives me a white rectangle covering the region. If I 
> change the parameter size=7 to 3 I can see some small cells with mostly blue 
> colors. Param=feature. What is wrong; if anything? (I have checked the syntax 
> and this is 
> the result every time). 
> 
> (By the way a good book :-)!)
> 
> 2. Is there a way you can to a "density" analysis a la ArcView 
> SpatialAnalyst; with sites (i e point) data? How?
> 
> Regards
> 
> Lars Forseth
> 
> 



More information about the grass-user mailing list