Hi, Not sure I understand your question. Suppose `data1` is your real data, but if the column names are different, change "V21", "V2" by those in the real data. Based on your initial post, the column names seemed to be the same. mean(data1$V21[data1$V2==1|data1$V2==0])
A.K. What values would I substitute by real data. I did everything the way you posted, and I got 3.8 as well. So I'm curious what values I would change to get the mean for the actual data? ----- Original Message ----- From: arun <smartpink...@yahoo.com> To: R help <r-help@r-project.org> Cc: Sent: Thursday, July 11, 2013 9:21 PM Subject: Re: Help with IF command strings HI, Try this: set.seed(485) dat1<- as.data.frame(matrix(sample(0:10,26*10,replace=TRUE),ncol=26)) mean(dat1$V21[dat1$V2==1|dat1$V2==0]) #[1] 3.8 #or with(dat1,mean(V21[V2==1|V2==0])) #[1] 3.8 A.K. I have data in 26 columns, I'm trying to get a mean for column 21 only for the participants that are either 0 or 1 in column 2. One of the commands I tried looked something like this mean(data1$V21, if(V2 = 1)) So basically I need to have the program run a mean (and later other forms of analysis) on participants based on their condition. either 0 or 1. Help is greatly appreciated. Thanks ______________________________________________ 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.
