> zz <- data.frame(a=c(1,2,3),b=c(4,5,6)) > zz a b 1 1 4 2 2 5 3 3 6 > a <- zz$a > a [1] 1 2 3 > a[2] <- 100 > a [1] 1 100 3 > zz a b 1 1 4 2 2 5 3 3 6 >
clearly a is a _copy_ of its namesake column in zz. when was the copy made? when a was modified? at assignment? is there a way to find out how much memory an object takes? gc() appears not to reclaim all memory after rm() - anyone can confirm? thanks! -- Sam Steingold (http://sds.podval.org/) on Ubuntu 11.10 (oneiric) X 11.0.11004000 http://www.childpsy.net/ http://mideasttruth.com http://americancensorship.org http://www.memritv.org http://jihadwatch.org http://ffii.org C combines the power of assembler with the portability of assembler. ______________________________________________ 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.
