[R] Memory question
krcabrer at epm.net.co
Thu Jul 14 12:32:11 CEST 2005
Thank you Dr. Spencer Graves for your answer.
What kind of matrices? They come form an image of about 3000x5000, and
I need to generate arround 1024 matrices of the same size, they are not
What function can I use to, once generated one matrix, I could save into
and then use the same space for the following, and so on.
Thank you very much for your help
Spencer Graves wrote:
> What kinds of matrices? There are facilities in the Matrix and
>SparseM packages that might help for sparse matrices. If they are N x k
>where N is large and k is not, can you compute something like the QR
>decomposition and get away with keeping only the R part for most of your
> One could potentially define a class of matrices that are only kept
>in memory only when needed; I think S-Plus may do that. It would take
>a lot of work to make that work generally, but you might be able to
>accomplish what you need with a much smaller effort.
> spencer graves
>Kenneth Roy Cabrera Torres wrote:
>>Hi R users and developers:
>>I want to know how can I save memory in R
>> - saving on disk a matrix.
>> - using again the matrix (changing their values)
>> - saving again the matrix on disk in a different file.
>>The idea is that I have a process that generate several
>>matrices, but if I keep them all in memory it will overflow.
>>How can I save them in different files, so I use the same
>>amount of memory for each processed matrix?
>>Thank you for your help.
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