Erin O'Doherty writes:
I need something that works like the "site characteristics report" in
s.menu but I want to include a radius around the site not a square.
I can't get away with just r.buffer because the buffers run together
and I'd have to sort out the sites to avoid overlap. I was hoping to
modify the code in s.menu to do a "circle" (I know it won't be a real
circle because it's a raster map) instead of a square, but I couldn't
figure out where it learns which cells to run stats on. I could
figure out a way to do it if I just had one site map to do this to,
but I have hundreds. What I want to do is describe the vegetation in
an error polygon around aerial telemetry locations. My veg map has a
resolution of about 3 m and the error polygon has a radius of 280 m.
If two sites fall in the same place I want to sample that area twice.
So if somebody could point me to the files in s.menu that I'd need to
change or figure out a slick way I could do this and repeat it for
many sets of sites, I'd be eternally grateful. Left to my own
devices I'll probably try something with r.mapcalc and r.stats.
The problem you're mentioning has been one of my concerns as well over
the last two years (basically, I wanted to obtain information about the
environment of archaeological sites within a certain radius). There is no
possibility to do this inside s.menu, unfortunately, so you should revert
to using shell-scripting. My solution was to zoom in on each site (using
the site_list as input for x,y-coordinates and then determining the
maximum extent I needed from there), and then create a 'circle' around
the site running r.los on a map called 'empty' (just zero's) with a
maximum distance of the desired radius. This produces a circular raster
map that could be used as a MASK that can be used to provide data from
r.stats. I could send you this script if you're interested, but I assume
the procedure will be clear to you. If you're really thinking of hacking
into s.menu, I'd be very much interested in any solution you might find.
Philip Verhagen
--
S t i c h t i n g R A A P
Regionaal Archeologisch Archiverings Projekt
adress: Plantage Muidergracht 14
1018 TV Amsterdam
THE NETHERLANDS
phone: (31) 20 525 5835
fax: (31) 20 525 5834
e-mail: motte@xs4all.nl