> -----Original Message----- > From: [EMAIL PROTECTED] > [mailto:[EMAIL PROTECTED] On Behalf Of Kunzler, Andreas > Sent: Thursday, July 24, 2008 7:45 AM > To: [EMAIL PROTECTED] > Cc: r-help@r-project.org; [EMAIL PROTECTED] > Subject: Re: [R] NAs - NAs are not allowed in subscripted assignments > > Hy Richie, thank you for the quick response. > > Unfortunately my problems hold on. > > Once again: 2 vectors (numeric) including NAs > My intention: I want to replace the values of vector a that > are smaller > than 2 and larger than 3 into NAs only in case vector b equals 1 > > a <- c(rep(seq(1,4),4),NA,NA) > b <- c(rep(seq(1,2),7),NA,NA,1,2) > > data.frame(a,b) > a b > 1 1 1 > 2 2 2 > 3 3 1 > 4 4 2 > 5 1 1 > 6 2 2 > 7 3 1 > 8 4 2 > 9 1 1 > 10 2 2 > 11 3 1 > 12 4 2 > 13 1 1 > 14 2 2 > 15 3 NA > 16 4 NA > 17 NA 1 > 18 NA 2 > > > me <- a[b==1][a[b==1]<2 | a[b==1]>3] > you <- a[a[b==1]<2 | a[b==1]>3] > > There are some differences > > length(me) > [1] 7 > length(you) > [1] 12 > > me > [1] 1 1 1 1 NA NA NA > you > [1] 1 3 1 3 NA NA NA 3 1 3 NA NA > > Your vector is containing the value 3. And in our case this > value would > be replaced by NA. > > I belive that in this case > > a[b==1]<2 | a[b==1]>3 > [1] TRUE FALSE TRUE FALSE TRUE FALSE TRUE NA NA NA > > Would be applied on the FIRST 10 values of a and then will be > repeated. > > Maybe it would be possible to do something like > > a[(a<2 & b==1) | (a>3 & b==1)] > > Is it allowed to construct double indices like > vector[][] ? > > > <<<snip>>>
I played a bit with this and haven't worked out all the nuances of indexing with logical statements, but I think this will do what you want. a[which(a[b==1]<2 | a[b==1]>3)] Hope this is helpful, Dan Daniel J. Nordlund Washington State Department of Social and Health Services Planning, Performance, and Accountability Research and Data Analysis Division Olympia, WA 98504-5204 ______________________________________________ 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.
