'x' is a rank 5 matrix from which you want to create a rank 10 crossproduct! Try the following instead:
x <- array(rnorm(100 * nitems, 3, 3), c(100, nitems)) sigma <- crossprod(x) I hope it helps. Best, Dimitris ---- Dimitris Rizopoulos Ph.D. Student Biostatistical Centre School of Public Health Catholic University of Leuven Address: Kapucijnenvoer 35, Leuven, Belgium Tel: +32/(0)16/336899 Fax: +32/(0)16/337015 Web: http://www.med.kuleuven.be/biostat/ http://www.student.kuleuven.be/~m0390867/dimitris.htm ----- Original Message ----- From: "Marc Bernard" <[EMAIL PROTECTED]> To: <r-help@stat.math.ethz.ch> Sent: Thursday, October 06, 2005 3:11 PM Subject: [R] Singular matrix > Dear All, > > I have written the following programs to find a non-singular > (10*10) covariance matrix. > Here is the program: > > nitems <- 10 > > x <- array(rnorm(5*nitems,3,3), c(5,nitems)) > > sigma <- t(x)%*%x > > inverse <- try(solve(sigma), TRUE) > > > > while(inherits(inverse, "try-error")) > > { > > x <- array(rnorm(5*nitems,3,3), c(5,nitems)) > > sigma <- t(x)%*%x > > inverse <- try(solve(sigma), TRUE) > > } > > > > The loop doesn't stop ... This means that no "non-singular" matrix > was found!!! > > some thing wrong !! > > > > Thanks a lot for any reply > > > > Bernard > > > > > > > > > > --------------------------------- > > > [[alternative HTML version deleted]] > > ______________________________________________ > R-help@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 > Disclaimer: http://www.kuleuven.be/cwis/email_disclaimer.htm ______________________________________________ R-help@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
