Do it in chunks of rows. /H On Sat, Jan 17, 2009 at 6:55 AM, Gundala Viswanath <gunda...@gmail.com> wrote: > Hi Hadley, > > I had to do it by line. Because, in practice, I will > manipulate the figures and string before printing it. > > And I can't bind these results into one new object, > because there are literally millions of this lines, and > R object can't handle that in my 4GB Ram memory. > > I tried your suggestion already, I have memory problem > >> x <- cbind(dat$V1, as.character(dat$V2)) > Error: cannot allocate vector of size 4.2 Gb > Execution halted > > - Gundala Viswanath > Jakarta - Indonesia > > > > On Sat, Jan 17, 2009 at 11:39 PM, hadley wickham <h.wick...@gmail.com> wrote: >> On Sat, Jan 17, 2009 at 7:59 AM, gundalav <gunda...@gmail.com> wrote: >>> Dear Jim and all, >>> >>> Allow me to ask your expert opinion. >>> >>> >>> Using the data (16Mb) downloadable from here: >>> >>> http://drop.io/gundalav/asset/test-data-zip >>> >>> >>> It took this long under 1994.070Mhz Cpu Linux, using >>> "write.table" >>> >>>> proc.time() - ptm1 >>> user system elapsed >>> 16581.833 5787.228 21386.064 >>> >>> >>> >>> __MYCODE__ >>> >>> args <- commandArgs(trailingOnly=FALSE) >>> fname <- args[3] >>> dat <- read.delim(fname, header=FALSE); >>> >>> output <- file('output_writetable.txt', 'w') >>> >>> >>> ptm1 <- proc.time() >>> for (i in 1:nrow(dat)) { >>> >>> #cat(dat$V1[i]," ", as.character(dat$V2[i]),"\n", sep="") >>> write.table(cbind(dat$V1[i], as.character(dat$V2[i])), >>> file=output, sep="\t", quote=FALSE, col.names=FALSE, row.names=FALSE) >>> } >>> >>> close(output) >>> proc.time() - ptm1 >>> __END__ >>> >>> Perhaps I misunderstood you. But seems that this is >>> truly slow. Is there a way I can speed it up? >> >> Don't do it line by line! >> >> write.table(dat[, c("V1", "V2")], file='output_writetable.txt', >> sep="\t", quote=FALSE, col.names=FALSE, row.names=FALSE) >> >> Hadley >> >> -- >> http://had.co.nz/ >> > > ______________________________________________ > 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.
