Re: Setting Mexico data to _FillValue

From: Mary Haley <haley_at_nyahnyahspammersnyahnyah>
Date: Thu, 28 May 2009 10:27:03 -0600 (MDT)


I'm afraid this is not possible. The graphical area mapping stuff
doesn't have any way to look at your data to determine what
areas to set to missing.

We've had lots of requests for this capability, however, and it's on
our to-do list. I can't make any estimates as to when we'll get to it

I think in this case, Dennis' suggestion is the best one so far.


On Thu, 28 May 2009, Eric D. Robinson wrote:

> Mary,
> I actually need to do some calculations using only the CONUS data, so I
> need to eliminate the data as opposed to just covering it up graphically. Is
> there a way that I can use the information in the mpAreaNames (et al.)
> databases to create an array and then use mask to eliminate the data. I know
> that you can set mpAreaMasking to mask say just Mexico graphically and that
> you can use the getvalues function to retrieve a list of the Names (or Types)
> used in the plot, but I was wondering if I can somehow query the AreaType on
> a point by point basis and create an array that way. For example, I think
> that all the US states in the Ncarg4_0 database have an mpAreaTypes value of
> 6, so if I can check every point in my domain for it's respective mpAreaTypes
> value, and only save points with value 6, I think I could create a mask array
> and then use mask to get rid of everything not in the US. Is this even
> remotely possible? Thanks for your help!
> -Eric
> Mary Haley wrote:
>> Hi Eric,
>> Dennis mentioned a way you might do this via calculations.
>> If all you are concerned about is not plotting the areas over the
>> ocean, Canada, and Mexico, then you can accomplish this by doing
>> graphical masking.
>> See example 4 at:
>> Also see attached script that shows the first frame with no masking,
>> and the second with. It's a goofy looking plot, but I was in a
>> hurry. :-)
>> --Mary
>> On Thu, 28 May 2009, Eric D. Robinson wrote:
>>> I have data that covers most of CONUS and part of the ocean, Canada, and
>>> Mexico. I would like to set all the data that is not over the CONUS to
>>> _FillValue. but I can't find an efficient way to do this. I know I can
>>> set the ocean data to _FillValue with the mask function since I have the
>>> land/sea mask, but I do not have a similar data set for political
>>> boundaries. Any suggestions would be appreciated. Thanks!
>>> -Eric
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Received on Thu May 28 2009 - 10:27:03 MDT

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