Re: band pass filter

The basic rule of data processing is to look at your data.

%> ncl_filedump olr.day.mean.nc

You would see that the variable is type short and it must be unpacked.

       short olr ( time, lat, lon )

Use
       x = short2flt( f->olr ) ; x(time,lat,lon)

=====================

Filter Example 3 reads the time series at *one* location

       x = f->$vName$(:,{0},{120}) ; Example 3

You filter *all* grid point in a region

   xBPF = wgt_runave_Wrap( x({lat|-20:20}, {lon|:}, time|:), wgt, 0)

   xBPF(lat,lon,time)

This is fine BUT later
you try to use an 'xy' plot function inappropriately

   plot(0) = gsn_csm_xy
(wks,yrfrac(iStrt:iLast),x(iStrt:iLast,{-20:20},:),res)

   res@gsnCenterString = "Band Pass Filtered: 20-100 day"
   plot(1) = gsn_csm_xy
(wks,yrfrac(iStrt:iLast),xBPF(:,:,iStrt:iLast),res)

which

Li Richard wrote:
> Hello everyone,
> I have applied a band pass filter to the daily interpolated OLR obtained
> from NOAA in order to extract signals of the Madden Julian Oscillation
> (MJO). However, error occurs when I'm going to run it and I really want
> to know what mistakes I have made. Thanks in advance for any assistance
> and help. The script can be seen in the attachment and the data i use is
> from
> (http://www.esrl.noaa.gov/psd/cgi-bin/db_search/DBSearch.pl?Dataset=NOAA+Interpolated+OLR&Variable=Outgoing+Longwave+Radiation
> <http://www.esrl.noaa.gov/psd/cgi-bin/db_search/DBSearch.pl?Dataset=NOAA+Interpolated+OLR&Variable=Outgoing+Longwave+Radiation>).
> Thanks.
> Regards,
> Richard
>
>
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Received on Sun Dec 13 07:56:17 2009