[ncl-talk] Missing value in data variable

[Nishtha Agrawal]

Hi,

Thanks for replying!

I understand that FFT is not allowing missing values. I therefore tried to
fill in these values using the poisson_grid_fill procedure, however the
procedure was too slow and I couldn't obtain the filled in data. I also
used linmsg to get linearly interpolated values in place of the missing
data, it was fast enough but I was obtaining the errors while using
mjo_wavenum_freq_season, it reported that division by 0 is taking place
somewhere and hence it couldn't proceed.

Thanks and Regards,
Nishtha

On Saturday, May 25, 2019, Dennis Shea <shea at ucar.edu> wrote:

> Sorry: I do not understand what you are attempting to do.
>
> The code within the *mjo_wavenum_freq_season*
> <http://www.ncl.ucar.edu/Document/Functions/Diagnostics/mjo_wavenum_freq_season.shtml>:
> function uses a (complex)  FFT and FFT's do not allow missing values.
>
> If you have an array with daily values: var(time,level,lat,lon)
>
> var2d = var(:,0,0,:)                        ; for clarity, explicitly
> extract the 2-dimensional subset
> *printVarSummary(*var2d)
> *printMinMax*(var2d,0)
> nmsg =*num*(*ismissing*(var2d))
> if (nmsg.eq.0) then
>     wf = *mjo_wavenum_freq_season* (var2d , date, "summer" , False)
>   ;;wf = *mjo_wavenum_freq_season* (var(:,0,0,:) , date, "summer" ,
> False)
> else
>     print(nmsg+" missing values. *mjo_wavenum_freq_season not invoked")*
>     exit
> end if
>
> On Fri, May 24, 2019 at 6:23 AM Nishtha Agrawal <
> agrawal.nishtha3 at gmail.com> wrote:
>
>> Hi,
>>
>> I have recently started using NCL, here I intend to use
>> mjo_wavenum_freq_season to obtain the frequency-wavelet spectrum of my
>> variable. But I am getting the missing value error while accessing the
>> function.
>>
>> I am using the following code for my 4D variable 'var'
>>
>> date=(/20170315, 20170330, 20170415, 20170430, 20170515, 20170530,
>> 20170615, 20170630/)
>> arr=ndtooned(var)
>> indi=ind_resolve(ind(ismissing(arr)),dimsizes(var))
>> ind_size=dimsizes(indi)
>> npts     = ind_size(0)       ; number of missing elements
>> ndim     = ind_size(1)       ; rank of var
>> print(ind_size)
>> print(npts)
>> print(ndim)
>> var at _FillValue = -999.9
>> do n=0,npts-1
>>   var(indi(n,0),indi(n,1),indi(n,2),indi(n,3)) = var at _FillValue
>> end do
>> wave=mjo_wavenum_freq_season(var(:,0,180,:),date, "summer",False)
>>
>> And I am getting
>>
>> (0) mjo_wavenum_freq_season: currently, missing data not allowed:
>> nMsg=308355
>>
>> I don't understand what else should I keep in place of -999.9. Please
>> provide any solution to this problem.
>>
>> Thanks and Regards,
>> Nishtha
>>
>> _______________________________________________
>> ncl-talk mailing list
>> ncl-talk at ucar.edu
>> List instructions, subscriber options, unsubscribe:
>> http://mailman.ucar.edu/mailman/listinfo/ncl-talk
>>
>
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mailman.ucar.edu/pipermail/ncl-talk/attachments/20190525/57bc8e4a/attachment.html>