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filerfor-loopfilenames

How to iterate over file names in a R script?

A very simple R script adds a ascending row index to a textfile "0.txt" and also adds a header "time" to it. After that the data is written to a file "0-edit.txt"

data<-read.table("0.txt", header=TRUE,sep=",",row.names= NULL);
colnames(data)[1] = "time"
write.table(data,quote=FALSE,sep=", ","0-edit.txt");

Assume i have 4 files called 0.txt, 1.txt, 2.txt, ...in the same folder, how can I use a counter (or something else) to iterate over those file names in my script?

Solution 
  • for(i in 0:3) {
  infile <- paste(i,".txt",sep="")
  outfile <- paste(i,"-edit.txt",sep="")

  data <- read.table(infile,header=TRUE,sep=",",row.names=NULL)
  colnames(data)[1] = "time"
  write.table(data,quote=FALSE,sep=", ",outfile)
}