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

[maning sambale]

Again (doh!) answering to my own query.

use r.series method=mode

my grass module of the day!

On Thu, Apr 16, 2009 at 4:51 PM, maning sambale
<emmanuel.sambale at gmail.com> wrote:
> 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/
> ------------------------------------------------------
>



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