From: Jim Lindsey <jlindsey@luc.ac.be> Message-Id: <9806020712.AA26573@alpha.luc.ac.be> Subject: R-beta: bugs and problems To: r-help@stat.math.ethz.ch (r-help) Date: Tue, 2 Jun 1998 09:12:58 +0200 (MET DST) The following are with R0.61.2 under Red Hat 5. If an MS-DOS file with CRs still in place is (accidently) read into R using scan(), an extra zero is added to each line. This can be very embarassing! In manipulating repeated measurements data, I generally require matrices. Unfortunately, matrix factors create a lot of problems. Consider the following simple examples: 1. > x <- as.factor(c("F","N",NA)) > y <- cbind(x,x) > y[,1] Error: length of "levels" vector and number of levels differ > attributes(y)$levels <- NULL > is.factor(y) TRUE > y[,1] F N NA 2. > rbind(NULL,gl(2,1,2)) Error in rbind(NULL,gl(2,1,2)): incompatible factors 3. To obtain the codes of a factor variable, one uses as.numeric(). However, this function destroys the properties of the matrix, turning it into a vector. Factors are very useful, but they are presently a mess for anything except simple applications in lm/glm. Jim -.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.- r-help mailing list -- Read http://www.ci.tuwien.ac.at/~hornik/R/R-FAQ.html Send "info", "help", or "[un]subscribe" (in the "body", not the subject !) To: r-help-request@stat.math.ethz.ch _._._._._._._._._._._._._._._._._._._._._._._._._._._._._._._._._._._._._._._._