Actually n^2 doubles. You could insert as.integer() around the call to round(runif()), to make the matrix have storage mode "integer", but when you call "eigen" you need a matrix of doubles anyway, so you're not really saving space. If your matrices are large and have mostly zeros, you might benefit from the SparseM package or the Matrix package. Reid Huntsinger -----Original Message----- From: r-help-bounces at stat.math.ethz.ch [mailto:r-help-bounces at stat.math.ethz.ch] On Behalf Of Mark Edmondson-Jones Sent: Wednesday, April 13, 2005 9:51 AM To: r-help at stat.math.ethz.ch Subject: [R] Binary Matrices 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. Thanks in advance for any help. Regards, Mark This message has been checked for viruses but the contents of an attachment may still contain software viruses, which could damage your computer system: you are advised to perform your own checks. Email communications with the University of Nottingham may be monitored as permitted by UK legislation. ______________________________________________ R-help at stat.math.ethz.ch mailing list https://stat.ethz.ch/mailman/listinfo/r-help PLEASE do read the posting guide! http://www.R-project.org/posting-guide.html
Binary Matrices
1 message · Huntsinger, Reid