You are using the connection the wrong way. You need to do something like:
fcon <- file("c:/data/perry/data.csv", open="r") for (iline in 1:slines) { isel <- isel + 1 cline <- readLines(fcon, n=1) ... } close(fcon) BTW, here's how I'd do it (not tested!): strvec <- rep("",slines) selected <- sort(sample(flines, slines)) skip <- c(0, diff(selected) - 1) fcon <- file("c:/data/[erry/data.csv", open="r") for (i in 1:length(skip)) { ## skip to the selected line readLines(fcon, n=skip[i]) strvec[i] <- readLines(fcon, n=1) } close(fcon) HTH, Andy > -----Original Message----- > From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] > Sent: Wednesday, August 27, 2003 7:19 PM > To: [EMAIL PROTECTED] > Subject: [R] Using files as connections > > > I have been trying to read a random sample of lines from a > file into a data frame using readLines(). The help indicates > that readLines() will start from the current line if the > connection is open, but presented with a closed connection it > will open it, start from the beginning, and close it when finished. > > In the code that follows I tried to open the file before > reading but apparently without success, because the result > was repeated copies of the first line: > > flines <- 107165 > slines <- 100 > selected <- sort(sample(flines,slines)) > strvec <- rep("",slines) > file("c:/data/perry/data.csv",open="r") > isel <- 0 > for (iline in 1:slines) { > isel <- isel + 1 > cline <- readLines("c:/data/perry/data.csv",n=1) > if (iline == selected[isel]) strvec[isel] <- cline else > isel <- isel - 1 > } > close("c:/data/perry/data.csv") > sel.flows <- read.table(textConnection(strvec), header=FALSE, sep=",") > > > There was also an error "no applicable method" for close. > > Comments gratefully received. > > Murray Jorgensen > > ______________________________________________ > [EMAIL PROTECTED] mailing list > https://www.stat.math.ethz.ch/mailman/listinfo> /r-help > ------------------------------------------------------------------------------ Notice: This e-mail message, together with any attachments,...{{dropped}} ______________________________________________ [EMAIL PROTECTED] mailing list https://www.stat.math.ethz.ch/mailman/listinfo/r-help