Dear Helmut,
On Sat, Jan 3, 2015 at 1:49 PM, Helmut Kudrnovsky hel...@web.de wrote:
as the extent of the r.slope.aspect output is 1 pixel less then DEM input,
the extent of the calculation output shrinks from one step to the next as
the resolution is coarsening.
any idea how to overcome such
Hi Pietro,
this is not a bug.
I unterstand the same. my question is more about how to implemented the
mentioned iterative algorithm which uses coarser resolution by each step and
how to avoid an extent shrinking of e.g. about 400m with the coarsest
resolution.
-
best regards
Helmut
--
Helmut,
you can use r.resamp.rst which computes slope and aspect and does not shrink
the region. But you may need to adjust the parameters
to make sure it works well.
Another way would be to modify r.slope.aspect to compute the values at the
edges - a second order polynomial min.square
Helmut Kudrnovsky wrote
hi devs,
I've added a script [1] with following calculations ideas:
- do some calculations with r.slope.aspect output
- coarse the resolution (but meet the DEM extent)
- do some calculations with r.slope.aspect output at the coarser
resolution
- coarse the
Dear Helena,
I believe that any reasonable estimate is better than the current
shrinking region (in r.flow we just
propagate the same values to the edges), but that does not seem to be the
consensus.
I agree with you that a reasonable estimate is better than the current
situation.
I've
hi devs,
I've added a script [1] with following calculations ideas:
- do some calculations with r.slope.aspect output
- coarse the resolution (but meet the DEM extent)
- do some calculations with r.slope.aspect output at the coarser resolution
- coarse the resolution again (but meet the DEM
