Hi, You can try either one of these: dat1<-read.table(text=" Ref_Pos Ref_Allele Var_Allele Var_Freq 1 A A 100 2 T G 50 3 G G 100 4 G T 45 5 T C 80 ",sep="",header=TRUE,stringsAsFactors=FALSE)
dat2<-dat1[unlist(lapply(split(dat1[,2:3],1:nrow(dat1[,2:3])),function(x) unlist(gregexpr(x[1],x[2]))!=1),use.names=FALSE),] dat2 # Ref_Pos Ref_Allele Var_Allele Var_Freq #2 2 T G 50 #4 4 G T 45 #5 5 T C 80 #or dat3<-dat1[apply(dat1,1,function(x) x[2]!=x[3]),] dat3 # Ref_Pos Ref_Allele Var_Allele Var_Freq #2 2 T G 50 #4 4 G T 45 #5 5 T C 80 #or dat4<-dat1[dat1[,2]!=dat1[,3],] dat4 # Ref_Pos Ref_Allele Var_Allele Var_Freq #2 2 T G 50 #4 4 G T 45 #5 5 T C 80 identical(dat2,dat3) #[1] TRUE identical(dat2,dat4) #[1] TRUE A.K. ----- Original Message ----- From: JDINIS <jorgemdi...@gmail.com> To: r-help@r-project.org Cc: Sent: Friday, October 26, 2012 10:26 AM Subject: [R] Delete row if two values in a matrix are equal Hi all and thank you for your time. I would like to delete rows from this matrix I call "var" if the character in Ref_Allele is equal to the character in Var_Allele. I have attached a before and after, to help my poor explanation. If someone could provide me with some code, or some guidance I would really appreciate it. Thank you again. "Before" > var Ref_Pos Ref_Allele Var_Allele Var_Freq 1 A A 100 2 T G 50 3 G G 100 4 G T 45 5 T C 80 "After" Ref_Pos Ref_Allele Var_Allele Var_Freq 2 T G 50 4 G T 45 5 T C 80 -- View this message in context: http://r.789695.n4.nabble.com/Delete-row-if-two-values-in-a-matrix-are-equal-tp4647554.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. ______________________________________________ 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.
