[GRASS-user] Re: r.neighbors modal filter for two raster layers

[maning sambale]

Revisiting this thread,  how do I add in the r.mapcalc command:

where if a pixel in the window contains a NULL value, do not count the
NULL in computing the mode

 For example if map 1 has many NULL values while map2 has valid
values, juts count the mode within map2.  This way I can patch areas
where map1 has NULLs.  And vise-versa if map2 has many NULLs.

The command below is OK when both maps have few NULL values.



On Fri, Jan 30, 2009 at 3:31 PM, maning sambale
<emmanuel.sambale at gmail.com> wrote:
> Well, it should be ","
>
> r.mapcalc "test_andmode = mode (map1[-1,-1] , map1[-1,0] , map1[-1,1]
> , map1[0,-1] , map1[1,-1] , map1[1,1] , map1[0,0] , map1[0,1] ,
> map1[-1,0] , map2[-1,-1] , map2[-1,0] , map2[-1,1] , map2[0,-1] ,
> map2[1,-1] , map2[1,1] , map2[0,0] , map2[0,1] , map2[-1,0])"
>
>
>
> On Fri, Jan 30, 2009 at 2:16 PM, maning sambale
> <emmanuel.sambale at gmail.com> wrote:
>> What operator in mapcalc should I use to evaluate a mode from a given window:
>> r.mapcalc "test_andmode = mode (map1[-1,-1] && map1[-1,0] &&
>> map1[-1,1] && map1[0,-1] && \
>> map1[1,-1] && map1[1,1] && map1[0,0] && map1[0,1] && map1[-1,0] &&
>> map2[-1,-1] && map2[-1,0] && \
>> map2[-1,1] && map2[0,-1] && map2[1,-1] && map2[1,1] && map2[0,0] &&
>> map2[0,1] && map2[-1,0])"
>>
>> Is the && correct to list values?
>>
>> On Fri, Jan 30, 2009 at 11:53 AM, maning sambale
>> <emmanuel.sambale at gmail.com> wrote:
>>> Hi,
>>>
>>> Any ideas in doing this:
>>>
>>> I want to get the mode of raster categorical values for a defined
>>> window based on 2 raster layers.
>>> For example, I set a window of 5x5, so I get mode value from 50 pixels
>>> (25 for raster a and 25 for raster 2).
>>>
>>> --
>>> cheers,
>>> maning
>>> ------------------------------------------------------
>>> "Freedom is still the most radical idea of all" -N.Branden
>>> wiki: http://esambale.wikispaces.com/
>>> blog: http://epsg4253.wordpress.com/
>>> ------------------------------------------------------
>>>
>>
>>
>>
>> --
>> cheers,
>> maning
>> ------------------------------------------------------
>> "Freedom is still the most radical idea of all" -N.Branden
>> wiki: http://esambale.wikispaces.com/
>> blog: http://epsg4253.wordpress.com/
>> ------------------------------------------------------
>>
>
>
>
> --
> cheers,
> maning
> ------------------------------------------------------
> "Freedom is still the most radical idea of all" -N.Branden
> wiki: http://esambale.wikispaces.com/
> blog: http://epsg4253.wordpress.com/
> ------------------------------------------------------
>



-- 
cheers,
maning
------------------------------------------------------
"Freedom is still the most radical idea of all" -N.Branden
wiki: http://esambale.wikispaces.com/
blog: http://epsg4253.wordpress.com/
------------------------------------------------------