Writing to a filename that varies depending on a variable in R

Using R in Windows 7

I have a program that creates a big matrix called patients. It also has a variable called filenum. I would like to write the file to a table that varies based on filenum. For instance, if filenum = 1, I'd like it to write out to

"c:\personal\output1"

How can I do this?

I've been pla开发者_JAVA百科ying with paste and a little with gsub, but I can't get this to work

Thanks in advance

Peter

You could do this via lapply(split(), write.table, ...) or the equivalent function from plyr, but it would probably be fastest and cleanest to do this with a for loop. Something like:

for(fnum in unique(patients[,"filenum"])) {
  set <- which(patients[,"filenum"] == fnum)
  write.table(patients[set,], paste("c:/personal/output",fnum,sep=""))
}