[ncl-talk] Crash with eofunc_varimax_Wrap function

Tue Jul 26 17:04:32 MDT 2016

Hi Dennis,

Thank you again for your assistance with my issue of the
eofunc_varimax_Wrap function stalling. I was able to produce REOF plots of
the annually averaged data. However, I am running into the same issue of
the eofunc_varimax_Wrap function stalling when I use the original monthly
data as well as using a weighted seasonal average instead of a weighted
annual average.

I am wondering if you could explain your modifications to the script I sent
you. I am also wondering if you have an idea as to why now the original
monthly dataset and the weighted seasonally averaged dataset stall with the
eofunc_varimax_Wrap function.

Thanks again for all your help.

Kind regards,
Allison

On Thu, Jun 30, 2016 at 8:09 AM, Dennis Shea <shea at ucar.edu> wrote:

> offline from ncl-talk
>
> re my comment:
>
> I am not sure why you want to rotate.
> The 1st two modes look very distinct.
>
> ===
>
> Deriving a "global" eof is rather unusual for ocean grids. The atmosphere
> is 'continuous'. The oceans are 'discontinuous' due to the continents. The
> EOFs may be though of as orthogonal structures that result from
> covariances.  Deriving a 'global' EOF is implicitly 'saying' that SST
> variations in the Kuroshio may be related to the Gulf Stream.
>
> An Example of using an EOF analysis over the ocean is:
>
> http://www.ncl.ucar.edu/Applications/eof.shtml
> Example 3
>
> Good Luck
>
>
>
> On Wed, Jun 29, 2016 at 4:17 PM, Dennis Shea <shea at ucar.edu> wrote:
>
>> Hi Allison,
>>
>> Can you please try the attached?
>>
>> I am not sure why you want to rotate.
>> The 1st two modes look very distinct.
>>
>> I did not plot anything. I'll let that to you
>>
>>
>> THX
>> D
>>
>> On Tue, Jun 28, 2016 at 8:07 AM, Allison Serakos <sera0021 at umn.edu>
>> wrote:
>>
>>> script name: ncl-talk_reof.ncl
>>> data file name: HadISST_sst.nc.gz
>>>
>>> Thank you,
>>> Allison
>>>
>>> On Mon, Jun 27, 2016 at 1:49 PM, Allison Serakos <sera0021 at umn.edu>
>>> wrote:
>>>
>>>> Hello,
>>>>
>>>>
>>>>
>>>> I am using the eofunc_varimax_Wrap function to analyze global rotated
>>>> EOFs produced from the eofunc_Wrap function. However, when I run my script,
>>>> it hangs when it reaches the eofunc_varimax_Wrap function. The script does
>>>> not finish and I get no error message.
>>>>
>>>>
>>>>
>>>> The dataset that I am using is the HadISST 1.1 monthly average sea
>>>> surface temperature dataset. It is a 3-dimensional (time, latitude,
>>>> longitude) global 1° x 1° grid dataset with 1755 time values, 180
>>>> latitude, and 360 longitude. I produce annually averaged values and
>>>> spatially weighted it prior to the EOF analysis.
>>>>
>>>>
>>>>
>>>> I have been using a Mac machine with NCL version 6.3.0 and a Linux
>>>> machine with NCL version 6.2.1 and the program hangs when conducting the
>>>> rotation.
>>>>
>>>>
>>>>
>>>> I tried running the script with global data for different time periods
>>>> (all between 113 and 102 years of global data) on both the Mac and Linux
>>>> machines and found that the function works only for some time periods
>>>> and crashes with others. These periods differ between the two Mac and Linux
>>>> machines that I used. I also tried reshaping the data from a 3D matrix
>>>> to a 2D matrix using the reshape function and combining the spatial
>>>> components. In this situation, the rotation output was still the same as
>>>> above for the respective time periods and machines. Additionally, I tried
>>>> reducing the spatial domain and found that when I reduce the latitude range
>>>> (anything smaller than 69S-90N) for any time period the script runs on
>>>> both machines and the function does not crash.
>>>>
>>>>
>>>>
>>>> I used ‘ncl –x’ to see if there is an error in my script, but the
>>>> script only crashes before the eofunc_varimax_Warp function with no
>>>> messages. When I run the script, NCL uses about 592.5MB of the 12GB of
>>>> memory on the Mac machine, so I do not believe this an issue of lack of
>>>> memory space.
>>>>
>>>>
>>>>
>>>> I am wondering if there is a known problem with the eofunc_varimax_Wrap
>>>> function? I am also wondering if you have any thoughts as to why the
>>>> function may be crashing under certain situations and not others?
>>>>
>>>>
>>>>
>>>> Here is a copy of my EOF and Varimax Rotation script:
>>>>
>>>> ;----------------------------------------------------------------
>>>>
>>>> ;***** EOF *****
>>>>
>>>> neval = 6
>>>>
>>>> optEOF = True
>>>>
>>>> optEOF at method = "transpose"
>>>>
>>>> optEOF at jopt = 0
>>>>
>>>>
>>>>
>>>> eof = eofunc_Wrap(av,neval,optEOF)
>>>>
>>>>
>>>>
>>>> ;***** VARIMAX ROTATION *****
>>>>
>>>> eof_rot = eofunc_varimax_Wrap(eof,-1)
>>>>
>>>> eof_varimax_reorder(eof_rot)
>>>>
>>>> ;----------------------------------------------------------------
>>>>
>>>>
>>>>
>>>> Thanks for your help in advance.
>>>>
>>>>
>>>>
>>>> Kind regards,
>>>>
>>>> Allison
>>>>
>>>>
>>>> --
>>>> Allison Serakos
>>>> Graduate Research Assistant
>>>> Department of Soil, Water, and Climate
>>>> University of Minnesota
>>>> 1991 Upper Buford Circle, Rm S535
>>>> St. Paul, MN 55108
>>>>
>>>
>>>
>>>
>>> --
>>> Allison Serakos
>>> Graduate Research Assistant
>>> Department of Soil, Water, and Climate
>>> University of Minnesota
>>> 1991 Upper Buford Circle, Rm S535
>>> St. Paul, MN 55108
>>>
>>> _______________________________________________
>>> ncl-talk mailing list
>>> ncl-talk at ucar.edu
>>> List instructions, subscriber options, unsubscribe:
>>> http://mailman.ucar.edu/mailman/listinfo/ncl-talk
>>>
>>>
>>
>

-- 
Allison Serakos
Graduate Research Assistant
Department of Soil, Water, and Climate
University of Minnesota
1991 Upper Buford Circle, Rm S535
St. Paul, MN 55108
-------------- next part --------------
An HTML attachment was scrubbed...
URL: http://mailman.ucar.edu/pipermail/ncl-talk/attachments/20160726/16e2e58b/attachment.html 