I noted the following R/S differences: *) read.table behaves differently when determining the rownames. If row.names is not given, S+ uses the first nonnumeric field with no duplicates as the row names, whereas R uses 1:n as rownames in this case. *) In S+ it is possible to sum over the lines of a data.frame. The behavior of R might be more accurate in that situation, since a data.frame is a list, but this causes problems, if one wants to use code written for S+ in R. S> aa<-data.frame(matrix(1:4,nrow=3D1)) S> sum(aa) [1] 10 R> aa<-data.frame(matrix(1:4,nrow=3D1)) R> sum(aa) Error in sum(..., na.rm =3D na.rm) : invalid argument type *) The as.vector argument removes the vector names in S+. I do not think that this difference can cause any problems, but I report it just for completeness. R> aa<-1:3 R> names(aa)<-letters[1:3] R> as.vector(aa) a b c=20 1 2 3=20 R> names(as.vector(aa)) [1] "a" "b" "c" S> aa<-1:3 S> names(aa)<-letters[1:3] S> as.vector(aa) [1] 1 2 3 S> names(as.vector(aa)) NULL As a final question. Does anyone know whether there is code for nnls.fit (Linear least-squares fit with coefficients constrained to be nonnegative.) available for R? Thanks, Andreas ************************************************************************ * Andreas Weingessel * ************************************************************************ * Institut f=FCr Statistik * Tel: (+43 1) 58801 4541 * * Technische Universit=E4t Wien * Fax: (+43 1) 504 14 98 * * Wiedner Hauptstr. 8-10/1071 * Andreas.Weingessel@ci.tuwien.ac.at * * A-1040 Wien, Austria * http://www.ci.tuwien.ac.at/~weingessel * ************************************************************************ -.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.- r-devel 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-devel-request@stat.math.ethz.ch _._._._._._._._._._._._._._._._._._._._._._._._._._._._._._._._._._._._._._._._