[ncl-talk] lanczos filter

Dennis Shea shea at ucar.edu
Tue Sep 13 12:32:46 MDT 2016


Not sure what the issue is with GrADS. That is between you and GrADS.

==
Attached is 'my' script to produce the netCDF. 'ncdump -h' has no problem
with the resulting file.

===
netcdf xBPF {
dimensions:
    time = UNLIMITED ; // (3652 currently)
    lat = 73 ;
    lon = 144 ;
variables:
    float xBPF(time, lat, lon) ;
        xBPF:_FillValue = 32766.f ;
        xBPF:long_name = "Anomalies: mean Daily U-wind" ;
        xBPF:units = "m/s" ;
        xBPF:wgt_runave_op_ncl = "wgt_runave_n" ;
    double time(time) ;
        time:units = "hours since 1-1-1 00:00:0.0" ;
        time:long_name = "Time" ;
        time:actual_range = 17259936., 17268672. ;
        time:delta_t = "0000-00-01 00:00:00" ;
        time:avg_period = "0000-00-01 00:00:00" ;
    float lat(lat) ;
        lat:units = "degrees_north" ;
        lat:actual_range = 90.f, -90.f ;
        lat:long_name = "Latitude" ;
    float lon(lon) ;
        lon:units = "degrees_east" ;
        lon:long_name = "Longitude" ;
        lon:actual_range = 0.f, 357.5f ;

// global attributes:
        :creation_date = "Tue Sep 13 12:25:42 MDT 2016" ;
        :Conventions = "None" ;
        :NCL = "filwgts_lanczos: ihp=2 nWgt=201 sigma=1 fca=0.01  fcb=0.05"
;
        :source_file = "./xBPF.nc" ;
        :title = "Lanczos Band Pass Filtered" ;
}


On Tue, Sep 13, 2016 at 7:07 AM, <marilia.gregorio at cptec.inpe.br> wrote:

> Oi Denis...
>
> I did what you told to me. But when I try to open the nc file at GRADS, I
> have the message:
>
> "entire grid undefined" .
>
> To write an output file I did this:
>
> ;***************************************************
> ; Writing OUTPUT
> ;***************************************************
>
>        diro="/home2/valesca/Documentos/ncl_filtrolanczos/"
>
>
> ;      print(""+eof_ts)
>
>       system("/bin/rm -f xBPF.nc") ; ao criar netcdf coloque sempre esta
> linha
>
>       fout=addfile("xBPF.nc","c")
>
>       ;fout->xVarWinterBPF= xVarWinterBPF
>       ;fout->xVarSummerBPF=xVarSummerBPF
>       ;fout->yVarWinterBPF=yVarWinterBPF
>       fout->xBPF=xBPF
>       ;fout-> yVarSummerBPF= yVarSummerBPF
>
>
> Thanks
>
> Marilia
>
>
> Em 2016-09-12 18:34, Dennis Shea escreveu:
>
>> Oi Marilia
>>
>> [SNIP]
>>
>> ;************************************************
>> ; create BandPass Filter
>> ;************************************************
>>   ihp      = 2                                    ; bpf=>band pass
>> filter => (BPF)
>>   nWgt     = 201
>>   sigma    = 1.0                              ; Lanczos sigma
>>   fca      = 1./100.
>>   fcb      = 1./20.
>>   wgt      = filwgts_lanczos (nWgt, ihp, fca, fcb, sigma )
>>
>> ;***********************************************************
>> ; Read daily U anomalies
>> ;***********************************************************
>>
>>    fili    = "uwnd.day."+plev+".anomalies.1980-2005.nc [2]"
>>
>>    f       = addfile (diri+fili , "r")
>>    TIME    = f->time                          ; days since ...
>>    YMD     = ut_calendar(TIME, -2)            ; entire (time,6)
>>
>>    iStrt   = ind(YMD.eq.ymdStrt)              ; index start
>>    iLast   = ind(YMD.eq.ymdLast)              ; index last
>>    delete(TIME)
>>    delete(YMD )
>>
>>    x       = f->U_anom(iStrt:iLast,:,:)       ; U_anom_sm
>>    printVarSummary(x)
>>    printMinMax(x, True)
>>
>>  [SNIP]
>>
>> ;************************************************
>> ; Apply the Lanczos band pass filter weights to the original anomalies
>> (time,lat,lon)
>> ;************************************************
>>
>>   xBPF = wgt_runave_n_Wrap (x, wgt, 0, 0)     ; BPF (Band Pass
>> Filtered)
>>
>> [SNIP]
>>
>> ==========
>>
>> If you do a
>>
>>   printVarSummary(xBPF)
>>
>>   printMinMax(xBPF,0)
>>
>> You will 'see' the xBPF contains the Lanczos filtered daily values.
>>
>> ========
>>
>> D
>>
>> On Mon, Sep 12, 2016 at 12:42 PM, <marilia.gregorio at cptec.inpe.br>
>> wrote:
>>
>> Hello, how are you?
>>>
>>> I'm trying to use the mjoclivar_3.ncl script, but would like to
>>> generate
>>> a field filtered by lanczos of method for every day, you guys know
>>> how I
>>> do it?
>>>
>>> Thank you.
>>> _______________________________________________
>>> ncl-talk mailing list
>>> ncl-talk at ucar.edu
>>> List instructions, subscriber options, unsubscribe:
>>> http://mailman.ucar.edu/mailman/listinfo/ncl-talk [1]
>>>
>>
>>
>>
>> Links:
>> ------
>> [1] http://mailman.ucar.edu/mailman/listinfo/ncl-talk
>> [2] http://anomalies.1980-2005.nc
>>
>
-------------- next part --------------
An HTML attachment was scrubbed...
URL: http://mailman.ucar.edu/pipermail/ncl-talk/attachments/20160913/ab82ec14/attachment.html 
-------------- next part --------------
A non-text attachment was scrubbed...
Name: marilia.xbpf.ncl
Type: text/x-ncl
Size: 2918 bytes
Desc: not available
Url : http://mailman.ucar.edu/pipermail/ncl-talk/attachments/20160913/ab82ec14/attachment.bin 


More information about the ncl-talk mailing list