[GRASS-dev] [bug #5008] (grass) r.neighbors: add null pass-through support

this bug's URL: http://intevation.de/rt/webrt?serial_num=5008
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Subject: r.neighbors: add null pass-through support

transferred here from #2398 due to spam bombing

Sun, May 9 2004 14:14:53 Request created by guest

Subject: r.neighbors: add null pass-through support

Platform: GNU/Linux/i386
grass obtained from: Mirror of Trento site
grass binary for platform: Compiled from Sources
GRASS Version: CVS April 2004

r.neighbors should have an option so output maps only contain data where data
exists in the original map.

Currently output maps 'grow' to the search distance, i.e.
output_val=mean(nonNULL(cell_values))
Maybe for completeness/correctness it should have an option to return a value
of null when there is ANY null data as part of the calculation, shrinking the
map at the region bounds and around any null cells, as mathematically the
neighborhood
analysis is only 100% valid in these areas. (-s strict?)

see 'r.series -n'

thanks,
Hamish

-------------------------------------------- Managed by Request Tracker

Request Tracker wrote:

this bug's URL: http://intevation.de/rt/webrt?serial_num=5008
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Subject: r.neighbors: add null pass-through support

Maybe for completeness/correctness it should have an option to return a value
of null when there is ANY null data as part of the calculation, shrinking the
map at the region bounds and around any null cells, as mathematically the
neighborhood analysis is only 100% valid in these areas. (-s strict?)

Agreed. There should be an option to propagate nulls.

--
Glynn Clements <glynn@gclements.plus.com>