Re: Setting Mexico data to _FillValue

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:
>
> http://www.ncl.ucar.edu/Applications/mask.shtml
>
> 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 - 10:22:10 MDT