Re: [ferret_users] eof_stat error message

[Domingos Urbano <dfurbano@xxxxxxxxxxxxx>]

Thanks Fabian,

I tried to use only a small portion of my grid; ie only 2s:2n and it runs very well. So that's all fine with Ferret!
My grid is to thin (1/4 degree resolution).

I'm now trying regrid and also cut the borders out to save memory (eg, indian out).

I didn't imagined that EOFs needed so much memory!

Thanks for your time.
Cheers,
Domingos.

On Dec 10, 2007 3:10 PM, Fabian Lienert < cccma-student-003@xxxxxxxx> wrote:

Hi Domingos,

I don't see how you used eof_stat, but the error message tells
you that there is not enough RAM for the computation (RAM, not swap).

If the resolution of the grid of the input data is high, inverting such a matrix in order to
find the EOFs uses a lot of RAM.
Calculating the EOFs in the northern Pacific (20N,65N) for 330 time steps needs about 800 MB of RAM
if the data is on a T63 grid (lon = 256, lat = 192).
Higher resolved input data leads to the use of more RAM. This behavior is not linear.

Fabian

Domingos Urbano wrote:
> Hello Ferrets,
>
> I have a time series of 240 time steps, 40N to 40S, global but z@ave,
> and want to compute EOF from pacific and atlantic region between 20N,20S
> region.
>
> But I had problem with the first step!
> What am I doing wrong?
> Is my external functions not installed correctly or my data is too big?
> I already set memory/size=1000 but nothing changed.
> Any help is welcome.
>
> Cheers,
> Domingos.
>
>
> yes? list/i=1/j=1 estat
>
> ERROR in efcn_compute() allocating -443066952 bytes of memory
>       work array 4:  X=1:2036716910, Y=1:1, Z=1:1, T=1:1
>  **ERROR: error in external function
> yes?
>
>
> --
> ---------------------------------------------------------------
> Dr. Domingos Urbano
> Grupo de Modelagem Acoplada Oceano-Atmosfera - GMA
> Centro de Previsão de Tempo e Estudos Climáticos - CPTEC
> Instituto Nacional de Pesquisas Espaciais - INPE
>
> Rodovia Presidente Dutra, km 40
> 12630-000 - Cachoeira Paulista - SP - Brasil
> tel: 55(12)3186.8552 fax: 55(12)3101.2835

> www.cptec.inpe.br <http://www.cptec.inpe.br>   www.inpe.br/ingles/
> <http://www.inpe.br/ingles/>
> ------------------------------------------------------

--
Fabian Lienert                  |  Canadian Centre for Climate Modelling and Analysis
PhD Student                     |  Meteorological Service of Canada
phone: +1(250)363-8242          |  University of Victoria
cccma-student-003@xxxxxxxx      |  P.O. Box 1700
http://www.cccma.bc.ec.gc.ca    |  Victoria, BC,  V8W 2Y2, Canada

-- 
---------------------------------------------------------------
 Dr. Domingos Urbano
 Grupo de Modelagem Acoplada Oceano-Atmosfera - GMA
 Centro de Previsão de Tempo e Estudos Climáticos - CPTEC
 Instituto Nacional de Pesquisas Espaciais - INPE

 Rodovia Presidente Dutra, km 40
 12630-000 - Cachoeira Paulista - SP - Brasil
 tel: 55(12)3186.8552 fax: 55(12)3101.2835
 
www.cptec.inpe.br   www.inpe.br/ingles/
------------------------------------------------------