[gradsusr] Is there any median function of GrADS

[Lee Byerle]

Hi Treng-Shui,
Attached is a sample script that might be helpful, which chooses a median ensemble member from 11 members.   The question is what variable/levels to use to define the median in an ensemble.  In this case the consensus is arbitrarily defined  as the member whose northern hemisphere area average 700 hPa geopotential height value at forecast hour 96 is closest to the area-averaged northern hemisphere, ensemble mean ("zave") 700 hPa geopotential height at forecast hour 96.  

In the sample ctl file opened in the script, the zdef corresponds to each 700 hPa ensemble member (this was made years before the ensemble dimension was introduced in GrADS ver 2).



good luck,
Lee


On Apr 7, 2012, at 11:43 AM, Huang Treng-Shi wrote:

> Dear all,
> 
>    I have a problem on drawing the median of an ensemble database.  Something like that "d median(t,e=1,e=20)" or so.  There is no build-in function for it.  Does any one knows how to perform it.
> 
> thanks a lot
>  
> 
> -- 
> Treng-Shi Huang (PhD)
> email: chinook.huang at gmail.com
> 
> _______________________________________________
> gradsusr mailing list
> gradsusr at gradsusr.org
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