# Re: PDF calculation for a grid node

From: Dennis Shea <shea_at_nyahnyahspammersnyahnyah>
Date: Tue Jul 16 2013 - 22:44:21 MDT

If:
ws(time,lev,lat,lon)

Then, at each grid point and level, the 'pdfx' over all times is:

do kl=0,klvl-1
do nl = 0, nlat-1
do ml = 0, mlon-1

nbins = ...
pdf_gridpt = pdfx( ws(:,kl,nl,ml),nbins,opt )
printVarSummary(pdf_gridpt)

; do whatever

delete(pdf_gridpt)

end do
end do
end do

===
For all levels and times

do nl = 0, nlat-1
do ml = 0, mlon-1

nbins = ...
pdf_gridpt = pdfx( ws(:,:,nl,ml),nbins,opt )
printVarSummary(pdf_gridpt)

; do whatever

delete(pdf_gridpt)

end do
end do

On 7/16/13 6:36 AM, Ioannis Koletsis wrote:
> Dear Mary and ncl-users,
>
> The point is to calculate the pdf for each grid point, in order to estimate
> the wind power potential for an area....
> When I run the script for one grid point (attached script1.ncl) the pdf
> calculation (as well as windpop calculation) was successfully done....
> The pdf calculation is depends on the bins number as well as on the maximum
> value of the wind speed distribution...
> For this reason, the bins number isn't constant for each grid point and may
> be varied because of the different wind speed distribution...
> It should be marked also, that the pdfx function seems to be 1-d...
>
> I have already done the following steps, without success:
>
> 1. Changing the ws variable dimensions (line 72 of script1.ncl), from one
> grid point to the desired grid node (line 71 of script1.ncl), the
> calculation has been completed and returned only one value instead of
> nlat*nlon values....
>
> 2. The script mary2_mods.ncl, which has been modified by Mary using reshape
> statement, didn't work and an error message has been appeared
> " warning:Argument 0 of the current function or procedure was coerced to the
> appropriate type and thus will not change if the function or procedure
> modifies its value
> fatal:(-2147483647) has no file extension, can't determine type of file to
> open
> fatal:No valid instance of variable time found in file list
> fatal:Execute: Error occurred at or near line 26 in file mary2_mods.ncl"
>
> 3. I believed that at the first script a do loop might be the solution, but
> it didn't work.....
>
> 4. The creation of a new variable wspdf with 4 dimensions including nbins
> number as the 4th dimension, it didn't work as the number of the bins isn't
> constant for each grid point....
>
> The source files are available at
> http://ensemblesrt3.dmi.dk/data/A2/C4I/DM/C4IRCA3_A2_ECHAM5_DM_25km_1961-197
> 0_wss.nc.gz
> http://ensemblesrt3.dmi.dk/data/A2/C4I/DM/C4IRCA3_A2_ECHAM5_DM_25km_1971-198
> 0_wss.nc.gz
> http://ensemblesrt3.dmi.dk/data/A2/C4I/DM/C4IRCA3_A2_ECHAM5_DM_25km_1981-199
> 0_wss.nc.gz
>
> If anyone has any idea, please share it with me....
>
> Any help would be appreciated....
>
>
>
>
> -----Original Message-----
> From: Mary Haley [mailto:haley@ucar.edu]
> Sent: Tuesday, July 16, 2013 1:01 AM
> To: Ioannis Koletsis
> Subject: Re: PDF calculation for a grid node
>
> Ioannis,
>
> I don't fully understand your script, but I got the reshape part to work.
>
> The reshape function is nothing more than this:
>
> function reshape(x,dims)
> begin
> return(onedtond(ndtooned(x),dims))
> end
>
> I'm not sure exactly what you are trying to bin, but see the attached script
> and see if this is what you want.
>
> Please, if you have further questions on this, post them back to ncl-talk,
> as I'm not always available.
>
> Thanks,
>
> --Mary
>
> -----
> No virus found in this message.
> Checked by AVG - www.avg.com
> Version: 2013.0.2904 / Virus Database: 3204/6492 - Release Date: 07/15/13
>
>
>
> _______________________________________________
> ncl-talk mailing list
> List instructions, subscriber options, unsubscribe:
> http://mailman.ucar.edu/mailman/listinfo/ncl-talk
>
_______________________________________________
ncl-talk mailing list
List instructions, subscriber options, unsubscribe:
http://mailman.ucar.edu/mailman/listinfo/ncl-talk
Received on Tue Jul 16 22:44:29 2013

This archive was generated by hypermail 2.1.8 : Fri Jul 19 2013 - 15:39:06 MDT