Hi [EMAIL PROTECTED] napsal dne 27.11.2008 11:48:32:
> > Hello! > I will repeat my question :what is there in a numeric(0)? > > In a function, I have several matrices with dimensions 288x1, also matrices > with dimensions > 0x1 (numeric(0)). > But I really do not know in which matrix there are elements or not. > So, these matrices that do not contain anything, if I am saying this > correctly, I would like to make them > matrices with the same dimensions as the first ones but with NA elements and > the ones with elements to remain as they > are. > For this reason, I thought to use the ifelse command. But I have problems > determining the arguments of this ifelse... > I tried to use: > A1 <- ifelse(nrow(A)==0,matrix(rep(NA,288),288,1),A) > > If A is a matrix with elements, then I get a A1 matrix with replicated 288 > times its first element, but I want the > initial A matrix. If A is a matrix with no elements (numeric(0)) then I get > only 1 NA. It is not a work for ifelse but for if. You want to test only one comparison not a vector of values. if(nrow(mat)==0) A1 <- matrix(NA, 288,1) else A1 <- A Regards Petr > > So, how can I test if there are elements in my matrix and if there are to > return itself the matrix and if there are not to get a matrix 288x1 with NAs? > Thank you for your time! > > Ismini > > ______________________________________________ > R-help@r-project.org mailing list > https://stat.ethz.ch/mailman/listinfo/r-help > PLEASE do read the posting guide http://www.R-project.org/posting-guide.html > and provide commented, minimal, self-contained, reproducible code. ______________________________________________ R-help@r-project.org mailing list https://stat.ethz.ch/mailman/listinfo/r-help PLEASE do read the posting guide http://www.R-project.org/posting-guide.html and provide commented, minimal, self-contained, reproducible code.