Lisa Wang <lisawang <at> uhnres.utoronto.ca> writes: : : Hi there, : : I'm writing a function which involves a loop. What to write in the "?" : place would allow it skips the "for loop" and goes to "a[i]<-0". : : a<-b[s>3,] : : if (nrow(a)==0) ????????????? : : for (i in 1:nrow(a)){ : a[i]<-1 : } : a[i]<-0
There are a number of errors in the above but I assume your question is how to set up a loop over an index of the rows of a so that the loop executes zero times if a has no rows. Try this: for(i in seq(len=nrow(a))) ... Also, depending on what you want to do, you might consider whether you need a loop in the first place. ______________________________________________ [EMAIL PROTECTED] mailing list https://www.stat.math.ethz.ch/mailman/listinfo/r-help PLEASE do read the posting guide! http://www.R-project.org/posting-guide.html