On 07/02/06 12:39, zhijie zhang wrote: > Dear friends, > i have a dataset like this: > x y z > 1 2 3 > 2 3 1 > 3 2 1 > 1 1 3 > 2 1 2 > 3 2 3 > 2 1 1 > I want to replace x with the following values:1<-a,2<-b,3<-c,4<-d; > replace y with the following values:1<-b,2<-a,3<-c,4<-d; > replace z with the following values:1<-d,2<-c,3<-b,4<-a;
Here's one way. Call your dataset M, and assume it is a data.frame. This method of replacement works best when you are replacing consecutive integers, as you are. Note that X[1] is "a", X[2] is "b" and so on. X <- c("a","b","c","d") Y <- c("b","a","c","d") Z <- c("d","c","b","a") M$x <- X[M$x] M$y <- Y[M$y] M$z <- Z[M$z] > Finally,select two subsets: > 1. if x='a'; > 2.x='a' and y='a'; M[M$x=="a",] M[M$x=="a" & M$y=="a",] The subsets will be rows. I'm not sure that's what you mean. Jon -- Jonathan Baron, Professor of Psychology, University of Pennsylvania Home page: http://www.sas.upenn.edu/~baron ______________________________________________ R-help@stat.math.ethz.ch mailing list https://stat.ethz.ch/mailman/listinfo/r-help PLEASE do read the posting guide! http://www.R-project.org/posting-guide.html