On 17-01-2012, at 11:35, Nerak wrote: > Dear all, > I have a question about the knowing for which row I have the max value of > one of my variables. > I calculated the Rsquared for different columns and made a list to gather > them. I unlisted this list to create a vector with this values. I want to > know for which column I have the max value of Rsquared. > The columns were always named in the same way. They always start with > results4$depth_ following by the number. The numbers are constructed as: > seq(1,10,0.1). But if the R squared values are now in 1 column, I don’t know > for which column they are calculated. So I made a new data frame with both > columns: > R2 <- unlist(LIST) > Cvalue <- c(seq(1,10,0.1)) > results5 <- data.frame(Cvalue,R2) > > # I know I can calculate the max value of Rsquared by this way: > > max(results5$R2) > > # now I want to know to which Cvalue this belongs. I would write it like > this: > results5$Cvalue[which(results5$R2 == "max(results5$R2)")] > # But I always get the solution: > numeric(0)
You haven't provided a reproducible example. So I tried this set.seed(1) x <- round(runif(10),3) x which.max(x) which(x==max(x)) x which(x=="0.945") which(x==max(x)) which(x=="max(x)") x[which(x=="max(x)")] If you run this you will see that the last line results in numeric(0). So; why are you using quotes in the which expression? Is results5$R2 a character string? This should work results5$Cvalue[which(results5$R2 == max(results5$R2))] But this is shorter results5$Cvalue[which.max[results5$R2)] Berend ______________________________________________ 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.
