Hi, >From your example data, dat1<- read.table(text=" id1 id2 value a b 10 c d 11 b a 10 c e 12 ",sep="",header=TRUE,stringsAsFactors=FALSE) #it is easier to get the output you wanted dat1[!duplicated(dat1$value),] # id1 id2 value #1 a b 10 #2 c d 11 #4 c e 12
But, if you have cases like the one below (assuming that all those instances were there is reversed order have the same value) dat2<- read.table(text=" id1 id2 value a b 10 c d 11 b a 10 e c 12 c e 12 ",sep="",header=TRUE,stringsAsFactors=FALSE) dat2[apply(dat2[,-3],1,function(x) {x1<- order(x); x1[1]<x1[2]}),] # id1 id2 value #1 a b 10 #2 c d 11 #5 c e 12 #or you have cases like these: dat3<- read.table(text=" id1 id2 value a b 10 c d 11 b a 10 a b 10 e c 12 c e 12 c d 11 ",sep="",header=TRUE,stringsAsFactors=FALSE) dat3New<-dat3[apply(dat3[,-3],1,function(x) {x1<- order(x); x1[1]<x1[2]}),] dat3New[!duplicated(dat3New$value),] # id1 id2 value #1 a b 10 #2 c d 11 #6 c e 12 A.K. >Hi everybody, > >I was hoping that someone could help me with this problem. I have a table with 3 columns. Some rows contain duplicates where the identifiers in >columns 1 and 2 are in reverse order, but the value associated with the row is the same. > >For example: > >id1 id2 value >a b 10 >c d 11 >b a 10 >c e 12 > >Rows 1 and 3 are duplicates (have the same value). I would like to retain only row 1 and delete row 3. Final table should look like this: > >id1 id2 value >a b 10 >c d 11 >c e 12 > >Thanks in advance for any help provided. > >Vince ______________________________________________ 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.