[GRASSLIST:4421] one column wide filtering

[Thomas Dewez]

Dear all,

I would like to pass a one-column-wide and 51-rows-high maximum filter on
a DEM. I found the maximum method in the r.neighbors command and the
custom-size filter in the r.mfilter. How is it possible to obtain combine
them?

Ultimately, I want to obtain an elevation profile of the ridge line of a
fault bounded mountain front. I was going to pick up the E-W trending
mountain ridge with the one-column-wide 51-pix-long maximum filter, then
use the resulting target pixels to produce a vector line and extract the
elevations within a buffer zone of the ridge line.

That's the result of my convoluted thoughts at the moment. Perhaps there
is an easier way to proceed, I am open to suggestions. 

Cheers,

Thomas