Hi, The rownames part is not clear as your expected output and input files didn't show them as rownames. ##Suppose you have all the files in a folder ##here I am creating the names of those files files1 <- paste0("sample", rep(1:777, each=29),"chr",1:29,".txt") length(files1) #[1] 22533 lst1 <-? split(files1,as.numeric(gsub(".*chr(\\d+)\\..*","\\1",files1))) ##use list.files() ##in your case, ##not tested lst1 <- split(list.files(pattern="sample\\d+"), as.numeric(gsub(".*chr(\\d+)\\..*","\\1",list.files(pattern="sample\\d+")))) ##in case other files are also in the folder library(plyr) lst2 <- lapply(lst1,function(x) {x1 <-join_all(lapply(x,function(y) read.table(y,header=TRUE,stringsAsFactors=FALSE,sep="")),c("Name","Chr","Position")) }) lapply(seq_along(lst2),function(i) write.table(lst2[[i]],paste0("LRRrawallchr",i,".txt"),row.names=FALSE,quote=FALSE)) ###if you need to create rownames using the first three columns: lapply(seq_along(lst2),function(i) {x1 <- lst2[[i]]; row.names(x1) <- as.character(interaction(x1[,1:3],sep="_")); x2 <- x1[,-(1:3)]; write.table(x2, paste0("LRRrawallchr",i,".txt"), quote=FALSE)}) A.K. I would like to use the `cbind` in a list of files. However each file are splited in a specific chromosome (chr) `(k in 1:29)`, and specific sample `(i in 1:777)`. The files are like: sample1chr1.txt, sample1chr2.txt ... sample1chr29.txt, sample2chr1.txt ... sample777chr29.txt All files have exactly the same rows names (3 first collumns represent my row names). I would like to get a final file to each chr merging to all sample files, with and do not repeat the row names in the final file (the first 3 collumns representing my rows names). I tried this: `#Creating file with row names (3 first collumns) to each Chr { {for(k in 1:29){ ? infile <- paste0("sample1chr",k,".txt") ? outfile <- paste0("LRRrawallchr",k,".txt") ? rows <- read.table(infile, header=TRUE, sep="\t") ? rows <- rows[, -grep("Log.R.Ratio", colnames(rows))] ? write.table(rows, outfile, sep=";")}}` `#Cbind in one file per Chr {? for(i in 1:777) ? for(k in 1:29){ ??? base <- paste0("LRRrawallchr",k,".txt") ??? chr <- read.table(base, header=TRUE, sep=";") ??? infile <- paste0("sample",i,"chr",k,".txt") ??? chr2 <- read.table(infile, header=TRUE, sep="\t") ??? outfile <- paste0("LRRrawallchr",k,".txt") ??? chr2 <- chr2[, -grep("Name", colnames(chr2))] ??? chr2 <- chr2[, -grep("Chr", colnames(chr2))] ??? chr2 <- chr2[, -grep("Position", colnames(chr2))] ??? chr <- cbind(chr, chr2) ??? write.table(chr, outfile, sep=";", row.names=FALSE, col.names=FALSE)} }` Input example (sample1chr1.txt): ?? ???? Name?? Chr Position sample1value ??? BAC-11034 1 128?????????? 0.302 ??? BAC-11044 1 129?????????? -0.56 ??? BAC-11057 1 134?????????? 0.0840 Input example (sample2chr1.txt): ??? Name?? Chr Position? sample2value ??? BAC-11034 1 128?????????? 0.25 ??? BAC-11044 1 129?????????? 0.41 ??? BAC-11057 1 134????????? -0.14 Expected output (LRRrawallchr1): ??? Name?????? Chr Position??? sample1value?? sample2value ??? BAC-11034 1 128??????? 0.302????????? 0.25 ??? BAC-11044 1 129??????? -0.56????????? 0.41 ??? BAC-11057 1 134??????? 0.0840???????? -0.14 I have 22553 diferent .txt files (29 files (one per chr) to each of 777 samples). All 22553 files (sample1chr1.txt, sample1chr2.txt ... sample1chr29.txt, sample2chr1.txt ... sample777chr29.txt) are like above example.? I wanna 29 files like (LRRrawallchr1), one per Chr. The "LRRrawallchr,k," files have to be with 777+3 (800 collumns). The 3 row names and one collumn per sample. Cheers!