[MITgcm-support] output frequencies NOT consistent

[Ed Hill]

On Wed, 2005-09-21 at 11:50 -0700, Paola Cessi wrote:
> I shoudl rephrase my problem more clearly:
> 
> In the example below, where niter0=400000 and all the dump, monitor, 
> timeave and pickup frequencies are 250000, the pickup files and the 
> timeaverages files are outputed at 500000 instead of 650000. In other 
> words I get pickup.0000500000.* and Ttave.0000500000.* instead of 
> pickup.0000650000.* and Ttave.0000650000.*. 
> The time-stamp on the files is consistent with an output well before the 
> end of the calculation.
> 
> However, the pickup.chkptA.* and the instantaneous fields (i.e. 
> T.0000650000.*) come out at time 6500000 (as they should).
> 
> Why?

Hi Paola,

The frequencies work according to the formula (simplified):

  IF DIFFERENT_MULTIPLE( time, freq )
     THEN write( ... )

and it seems that you want them to work like:

  IF DIFFERENT_MULTIPLE( (time - nIter0) , freq )
     THEN write( ... )

which is not the way things are done within the model.

However, if I understand you correctly, there *is* a very simple thing
that you can do to get the behavior that you want.  Simply re-name your
pickup files so that they start at an even multiple of the desired
frequency (say, 250000) and then set nIter0 to that value.  That should
give you the behavior you request.

Ed

-- 
Edward H. Hill III, PhD
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