Hello, I have a matrix of values that I want to convert to a vector, but remove certain entries in the matrix first, i.e. in the vector I want every value in the matrix that is greater than 1000. I would also like to find out how many values are excluded in the transition from matrix to vector. Could someone tell me how this can be done? Thank you in advance Arun Horne
A matrix is a vector with a dim attribute. The following should do what I understand of you to be asking: sel <- (Mat>1000) Vec <- Mat[sel] n.excl <- length(Mat)-length(Vec) hope this helps. spencer graves Arun Horne wrote:> Hello, > > I have a matrix of values that I want to convert to a vector, but remove > certain entries in the matrix first, i.e. in the vector I want every value > in the matrix that is greater than 1000. I would also like to find out how > many values are excluded in the transition from matrix to vector. Could > someone tell me how this can be done? > > Thank you in advance > Arun Horne > > ______________________________________________ > R-help at stat.math.ethz.ch mailing list > https://www.stat.math.ethz.ch/mailman/listinfo/r-help
On Tue, 1 Jul 2003, Arun Horne wrote:> I have a matrix of values that I want to convert to a vector, but remove > certain entries in the matrix first, i.e. in the vector I want every value > in the matrix that is greater than 1000. I would also like to find out how > many values are excluded in the transition from matrix to vector. Could > someone tell me how this can be done?start with matrix A, and treat it like a vector (which it is) vec <- A[A > 1000] (reads down columns, BTW) excluded <- sum(!(A > 1000)) -- Brian D. Ripley, ripley at stats.ox.ac.uk Professor of Applied Statistics, http://www.stats.ox.ac.uk/~ripley/ University of Oxford, Tel: +44 1865 272861 (self) 1 South Parks Road, +44 1865 272866 (PA) Oxford OX1 3TG, UK Fax: +44 1865 272595