Hello,
Shankar Lanke wrote > > Dear All, > > I have a data sets as shown below A (Patient ID ), B and C are the > Concentration of drug in blood on day 1 and day 4, D is the difference in > conc. To do this in R I have written a code as follows, identified the > number of patients who have more concentration on day 4 . Here I want to > identify specifically the patient ID (is he patient 1 or 2 or 5 and 7), > whose concentration is more. > How to write a code to get the list of A (patient ID whose difference is > more on day 4). > > Data<-(myDf$B-myDf$C) > sum(Data>0) > > A B CD (B-C) 1 14 10 4 2 12 7 5 3 11 15 -4 4 8 3 5 5 1 8 -7 > > I appreciate your help, thank you very much in advance. > > Regards > > [[alternative HTML version deleted]] > > ______________________________________________ > R-help@ 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. > If I understand it correctly, this should do it. x <- read.table(text=" A B C D 1 14 10 4 2 12 7 5 3 11 15 -4 4 8 3 5 5 1 8 -7 ", header=TRUE) which(x$D == max(x$D)) x$A[ which(x$D == max(x$D)) ] Or you can save the values of the which() function and use them when needed. Hope this helps, Rui Barradas -- View this message in context: http://r.789695.n4.nabble.com/Identifying-the-particular-X-or-Y-in-a-sorted-list-tp4605124p4606062.html Sent from the R help mailing list archive at Nabble.com. ______________________________________________ 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.