[GRASS-dev] [GRASS-SVN] r68080 - grass/trunk/raster/r.neighbors

[Markus Neteler]

Hi,

On Sat, Mar 19, 2016 at 8:51 AM,  <svn_grass at osgeo.org> wrote:
> Author: marisn
> Date: 2016-03-19 00:51:10 -0700 (Sat, 19 Mar 2016)
> New Revision: 68080
>
> Modified:
>    grass/trunk/raster/r.neighbors/r.neighbors.html
> Log:
> r.neighbors: list all methods in documentation (fixes #2965); Provide an example of use (related to #2620)
...
>
> +<h3>Measure occupancy of neighborhood</h3>
> +
> +Set up 10x10 computational region to aid visual inspection of results
>  <div class="code"><pre>
> -r.neighbors
> +g.region rows=10 cols=10
>  </pre></div>

Would you mind to change that to square pixels? I tried like this:

g.region n=229500 s=214500 w=630000 e=645000 res=1500 -p

but...

> +Fill 50% of computational region with randomly located cells.
> +"distance=0" will allow to fill adjacent cells.
> +<div class="code"><pre>
> +r.random.cells output=random_cells distance=0 ncells=50
> +</pre></div>


> +Count non-empty (not NULL) cells in 3x3 neighborhood
> +<div class="code"><pre>
> +r.neighbors input=random_cells output=counts method=count
> +</pre></div>
> +
> +Optionally - exclude centre cell from the count (= only look around)
> +<div class="code"><pre>
> +r.mapcalc "cound_around = if( isnull(random_cells), counts, counts - 1)"

--> coun*t*s(?)_around?

The example is not that obvious yet, perhaps d.rast.num would enrich it.

Markus