interpolating sites

[James Darrell McCauley]

Christine Weiss (cmw at nycparks.gov) writes on 21 Feb 94:
>Does GRASS have the capability to interpolate one site from multiple sites?  I want to "average" the sites, so to speak, of where wildlife was spotted to give me one site for each species surveyed within a given range.   
>
>Up till now, this has been done manually by techs who visually "averaged" the clusters of wildlife to determine the one point.  There's got to be an easier way.  
>Any pointers would be much appreciated.  Thanks,

I'm not real clear on what you mean, but how about:

 s.out.ascii -d file |\
  awk 'BEGIN {a=b=c=0} {a+=$1;b+=$2;c+=$3} END{print a/NR,b/NR,c/NR}'

This averages the easting, northing, and third field and prints
one site as output. Manually, I suppose that you could
use g.region/d.zoom to window the data (assuming that the clusters
are highly separable) but I wouldn't want to do this for lots of 
clusters.

--Darrell