[GRASSLIST:5010] reporting statistics from clumps of pixels

[Thomas Dewez]

Dear all,

I am struggling on how to extract statistics from clumps of data. I 
have a layer containing clumps ID and I would like to obtain an ascii 
output of the average elevation of those clumps.
Is there a command that does this?

r.average was used to compute the average value of each clump. 
The problem is simply to report the value contained in one layer 
while looking up the category value in another layer. The report 
would look something like this:

clump1, value...
clump2, value...
...

Surely it is quite basic

Thanks for your help,

Thomas