[GRASS-user] Re: Constrain the output of v.random

[Rainer M Krug]

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On 11/04/2010 05:49 PM, Hamish wrote:
> Rainer wrote:
>> Just another idea - an iterative approach in a script,
>> which is using v.random and to discard all points outside
>> the polygon and to repeat it until you have the number of
>> random points you need. This could be made faster, by using a
>> MASK based on the polygon which has been grown to
>> encapsulate the whole polygon, and to use on this setup
>> r.random, also iterative.
> 
> 
> see the v.random.cover script already in grass-Addons for this.
> :-)

I always love to find out if my ideas have already been implemented in
GRASS or other software - it never happened to me with proprietary software.

> 
> r.random points would be not-as-random, as results will all be
> aligned to the raster grid, possibly introducing aliasing
> problems.

True - I haven't considered that.

Thanks,

Rainer

> 
> 
> Hamish
> 
> 
> 
>       


- -- 
Rainer M. Krug, PhD (Conservation Ecology, SUN), MSc (Conservation
Biology, UCT), Dipl. Phys. (Germany)

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