Re: Problem extracting nc to txt

John,

Inside four nested loops, you are building very long strings, by
adding one element at a time. This is extremely inefficient in NCL,
because a copy of every new long substring is permanently stored in
program memory. So memory consumption is order (2) for what should be
an order (1) task. There is a similar relation for CPU time to copy
each long substring length(m) to the next longer substring
length(m+7). You can get away with this method for small arrays, but
it bogs down for larger arrays.

Try reshaping the 4-D numeric input array to a 2-D numeric output
array. Include extra columns for your index columns, lat and lon.
Then output the 2-D numeric array to a text file using write_matrix,
which has the desired format control.

--Dave

On Thu, Jun 13, 2013 at 7:14 AM, Ioannis Koletsis <koletsis@noa.gr> wrote:
> Dear ncl-users,
>
> I would like to extract from .nc file in a txt file with the lat, lon, ws
> format for each grid point, the wind speed values for a specific domain.
>
> Firstly, I tried to extract in to a txt file using the attached script
> (ex_alldata_Med_HH_3.ncl), but the script has been stuck and finally killed…
>
> I had had the same results with the simply script (dimbin3.ncl)…
>
> Secondly, I tried to extract my file into a binary file (script2:
> dimbin2.ncl), and everything was ok
>
> Have you got any idea what is going wrong with the first script???
>
> The source file for free downloading is available here….
>
> http://ensemblesrt3.dmi.dk/data/A2/C4I/DM/
>
>
>
> Any help would be appreciated
>
>
>
> John
>
>
>
>
>
> Dr. Ioannis Koletsis
>
> National Observatory of Athens
> Institute for Environmental Research
> Lofos Koufou
> 15236-Penteli
> Athens-Greece
> Tel: +30 210 8109203, Fax: +30 210 8103236
> e-mail: koletsis@meteo.noa.gr
>
> ----------------------------------------------------------------------------------------
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> or http://www.meteo.gr (in greek)
> Weather forecasts for Europe: http://www.eurometeo.gr (in english)
>
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>
>
>
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Received on Thu Jun 13 10:18:26 2013