regridding of time axis

[Chris Weaver <weaver@xxxxxxxxxxxxxxxxxxxxxxxxxxx>]

Hi Everyone,

I have 3-hourly meterological fields, and I want to create new variables which 
are the same fields only averaged over each day.  I'm having problems regridding 
the 3-hourly data to a once-a-day time axis (for eventual saving to a netcdf 
file).  It seems that I am not allowed to use the @ave regridding transformation 
on the time axis (only @asn works), regardless of whether I define my new time 
axis using calendar or time step notation.  Depending on the specific steps I 
take, sometimes ferret let's me perform the regridding, but when I try to 
display the daily-mean data I get an "all values flagged as bad" message.  Other 
times I get a message saying the regridding is prohibited except with the @asn 
transformation.

Displaying a daily-average of 8 3-hrly times works fine--I simply use:

fill omega[l=1:8@ave]    (but "let omega2 = omega[gl=1:8:8@ave]" doesn't work)

for example.  I could therefore calculate and write each day's daily average 
individually, but I would have to do this 31 times for each month.  Is there a 
better way.

Thanks very much for your help,

Chris Weaver




C.P. Weaver                                Internet:
Department of Environmental Sciences        weaver@cep.rutgers.edu
Rutgers University/Cook College             www.envsci.rutgers.edu/~weaver
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