R help - Dec 2012 - Large loops in R

Dear all,

I need to access data from a large matrix (48000 x 48000) and to do it
I am trying to run two loops using "for" command. Surely it is been a
very slow job.

I heard that "for" is not the best option to perform large loops in R,
but I don't really know what would be the best (fast) option. sapply?
vapply? Could anyone help me with this issue, please?

Thank you very much for your attention and for any help!

Best regards,

Charles

-- 
Um ax?! :)

--
Charles Novaes de Santana
http://www.imedea.uib-csic.es/~charles
PhD student - Global Change
Laboratorio Internacional de Cambio Global
Department of Global Change Research
Instituto Mediterr?neo de Estudios Avanzados(CSIC/UIB)
Calle Miquel Marques 21, 07190
Esporles - Islas Baleares - Espa?a

Office phone - +34 971 610 896
Cell phone - +34 660 207 940

On Dec 4, 2012, at 6:47 PM, Charles Novaes de Santana <charles.santana at
gmail.com> wrote:
> Dear all,
> 
> I need to access data from a large matrix (48000 x 48000) and to do it
> I am trying to run two loops using "for" command. Surely it is
been a
> very slow job.
> 
> I heard that "for" is not the best option to perform large loops
in R,
> but I don't really know what would be the best (fast) option. sapply?
> vapply? Could anyone help me with this issue, please?
What exactly are you trying to do? It's likely doable with a few vectorized
operations.

Michael 

> 
> Thank you very much for your attention and for any help!
> 
> Best regards,
> 
> Charles
> 
> -- 
> Um ax?! :)
> 
> --
> Charles Novaes de Santana
> http://www.imedea.uib-csic.es/~charles
> PhD student - Global Change
> Laboratorio Internacional de Cambio Global
> Department of Global Change Research
> Instituto Mediterr?neo de Estudios Avanzados(CSIC/UIB)
> Calle Miquel Marques 21, 07190
> Esporles - Islas Baleares - Espa?a
> 
> Office phone - +34 971 610 896
> Cell phone - +34 660 207 940
> 
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