I have a problem related with this question (Old question without answer: R.Neighbors with large neighborhoods?).
Basically, I want to estimate roughness of a given area, for which I was using QGIS, but I want to change the neigborhood size, so I'm using GRASS now because I didn't find a way to do that in QGIS. I am working with ASTER GDEM v2.
So I want to explore a circular neighborhood of aprox. 500m around each pixel and, since each pixel of ASTER GDEM v2 has aprox. 30m of width, I believe my neighborhood size should be of 17, right?
I selected "use circular neighborhood" and for method "average". The program runs and creates a new layer but then I cannot open the raster file. The "Map Display" shows a blank screen when I perform "zoom to selected maps" of the result layer. I tried to save the file as .tiff and open it in QGIS but I obtain, again, a blank screen, and the raster has no values (nan-nan).
Can someone help me please? I don't know if this problem is related with the parameters I am using or if it is related with the software!