Slope is a weighted average of sorts. Get the r.mapcalc paper
from moon.cecer.army.mil and read about slope and aspect and
you'll see (1) how r.slope.apsect does it and (2) how you can
devise your own formula.
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Michael Shapiro U.S. Army CERL
email: shapiro@zorro.cecer.army.mil Environmental Division
phone: (217) 352-6511 ext 526 P.O. Box 9005
fax: (217) 373-7222 Champaign, Ill. 61826-9005
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