Re: Outlier from Satelite Data

Xi

You've answered your own question; you can use the 'where()' function to remove any values that are outside an acceptable range.

How you decide what that acceptable range is will depend on your knowledge about the particular region, datasets and so on, is not really a question about NCL at all.

(That said, I would respectfully suggest that a negative value of precip is wrong, so you could always set zero to your lower bound…..)

Will

From: Xi Chang <xi.chang01@gmail.com<mailto:xi.chang01@gmail.com>>
Date: Thursday, 13 December 2012 10:09 AM
To: "ncl-talk@ucar.edu<mailto:ncl-talk@ucar.edu>" <ncl-talk@ucar.edu<mailto:ncl-talk@ucar.edu>>
Subject: Outlier from Satelite Data

Hallo NCL,
I am using precipitation dataset derived from Satellite estimate. When i check my data using stat_dispers i found that the max precip within my data over 300 mm/day. Is there any method how to remove the outlier ( how to determine them) ? i found in the last discussion, by setting something like this in the command, how to select the suitable range in this case.

   xBIG = ...
   xSMALL = ...
   x = where (x.lt.xSMALL .or x.gt.xBIG, x@_FillValue, x)

Thanks a lot.

Xi

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Received on Thu Dec 13 08:21:31 2012