Time averages...

[strandwg@xxxxxxxxxxxxx (Gary Strand)]

Suppose I have 24 months of data and want to create two annual averages (months
1-12 and months 13-24). What's the best and easiest way in ferret to do so? It
seems that doing:

let xaa = x[l=1:12@ave]
save/append/file=X.nc xaa
let xaa = x[l=13:24@ave]
save/append/file=X.nc xaa

gives me a dataset with only one time average.

I know there's difficulty in determining the "time stamp" of an average, and I
would really like to avoid creating a new variable for every time average, so
is there a way I can do what I want relatively readily?

I've found that generating a 12-month running average and extracting out the
correct single average isn't quite right because of the half weighting of the
ends.

Thanks for any advice/help anyone can offer.
-- 
Gary Strand
strandwg@ucar.edu                              http://www.cgd.ucar.edu/ccr/gary