Suggestion: Don't do the ifelse stuff below.
See ?switch instead. -- Bert On Sun, Aug 25, 2013 at 11:32 PM, arun <smartpink...@yahoo.com> wrote: > HI, > > It may be better to provide an example dataset using ?dput(). > dput(head(dataset),20) > > Try: > signal3<- ifelse(t.tr=="Pst 24", signal2-17.29, ifelse(t.tr=="Pst 48", > signal2 - 43.93256, etc.....)) > > > A.K. > > ----- Original Message ----- > From: "Fethe, Michael" <mfet...@utk.edu> > To: "r-help@r-project.org" <r-help@r-project.org> > Cc: > Sent: Sunday, August 25, 2013 9:31 PM > Subject: [R] If else loop problem: the condition has length > 1 and only the > first element will be used > > Hi all, > > I'm running an if else loop to normalize my data to a known control. > I have calculated values that need to be subtracted from each treatment > applied. I'm trying this within a for loop with if and else commands to apply > to correct subtraction. This is done as follows: > > > attach(data.2013) > > #Normalize to known control > > for(i in signal2) { > > if(t.tr=="Pst 24") {signal3=(signal2 - 17.29)} > > if(t.tr=="Pst 48") {signal3=(signal2 - 43.93256)} > > if(t.tr=="Pst 72") {signal3=(signal2 - 43.477468)} > > if(t.tr=="Pto 24") {signal3=(signal2 - 29.39875)} > > if(t.tr=="Pto 48") {signal3=(signal2 - 76.796645)} > > if(t.tr=="Pto 72") {signal3=(signal2 - 68.176174)} > > if(t.tr=="Pm 24") {signal3=(signal2 + 0.498333)} > > if(t.tr=="Pm 48") {signal3=(signal2 - 0.200417)} > > if(t.tr=="Pm 72") {signal3=(signal2 - 10.465507)} > > else {signal3=signal2} > > } > > > This code ran once with no problems or warnings. Now it produces a ton of > warnings of > > "the condition has length > 1 and only the first element will be used". > > > Here is str(data.2013) > > > 'data.frame': 4293 obs. of 8 variables: > > $ rep : Factor w/ 4 levels "R1","R2","R3",..: 1 1 1 1 1 1 1 1 1 1 ... > > $ construct: Factor w/ 10 levels "35S","46S","E1",..: 1 1 1 1 1 1 1 1 1 1 ... > > $ time : int 24 24 24 24 24 24 24 24 24 24 ... > > $ treatment: Factor w/ 8 levels "Mock","MockUN",..: 1 1 1 1 1 1 2 2 2 3 ... > > $ sample : int 1 2 3 4 5 6 1 2 3 1 ... > > $ signal : int 733750 665790 659550 676270 682770 600420 676350 652110 > 665350 798850 ... > > $ signal2 : num 734 666 660 676 683 ... > > $ t.tr : Factor w/ 24 levels "Mock 24","Mock 48",..: 1 1 1 1 1 1 4 4 4 7 > ... > > > > I'm really not sure why this ran once and now is giving me errors. > > Can anyone help? I've heard ifelse can be effective when running into this > error. However, this command does not function the way i would like. I need a > specific value subtracted from each treatment/time value. The only value that > should matter for subtracting the correct value is t.tr. > > > > [[alternative HTML version deleted]] > > ______________________________________________ > 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. -- Bert Gunter Genentech Nonclinical Biostatistics Internal Contact Info: Phone: 467-7374 Website: http://pharmadevelopment.roche.com/index/pdb/pdb-functional-groups/pdb-biostatistics/pdb-ncb-home.htm ______________________________________________ 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.