[R] Binary Matrices

[Uwe Ligges]

Mark Edmondson-Jones wrote:

> I'm wanting to perform analysis (e.g. using eigen()) of binary matrices - i.e. matrices comprising 0s and 1s.
> 
> For example:
> 
> n<-1000
> test.mat<-matrix(round(runif(n^2)),n,n)
> eigen(test.mat,only.values=T)
> 
> Is there a more efficient way of setting up test.mat, as each cell only requires a binary digit?  I imagine R is setting up a structure which could contain n^2 floats.

No. In principle you could use logicals, but that does not help for 
further calculations in eigen().

Uwe Ligges


> Thanks in advance for any help.
> 
> Regards,
> Mark
> 
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