[R] Huge matrix: allocation works but assignment fails

[Uwe Ligges]

Remi wrote:
> Hello everyone,
> 
> I am working with one big matrix:
> w=matrix(0,18000,18000)
> 
> on a Linux computer with 16Go of RAM.
> 
> I can actually create the matrix, and even access elements:
> w[10,10]
> 0
> 
> but if I try to change one element, it fails:
> w[10,10]=1

In this case your object is copied and you need two times the space for 
your object.

Best,
Uwe Ligges


> Erreur : impossible d'allouer un vecteur de taille 2531250 Ko
> (Failed to allocate a vector of size...)
> 
> What can I do? And, maybe even more important, how can one explains such 
> a behavior?
> 
> Thank you for any help/advice
> 
> Rémi Proville.
> 
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