[R] Large loops in R

[R. Michael Weylandt <michael.weylandt@gmail.com>]

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 axé! :)
> 
> --
> 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 Mediterráneo de Estudios Avanzados(CSIC/UIB)
> Calle Miquel Marques 21, 07190
> Esporles - Islas Baleares - España
> 
> Office phone - +34 971 610 896
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> 
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