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.
