>> Why do those lines need any allocations? I thought class<- and attr<- >> were primitives, and hence would modify in place. >> > > .. but only if there is no other reference to the data (i.e. NAMED < 2). If > there are two references, they have to copy, because it would change the > other copy. > Here, however, it already has NAMED=2 because of > > data <- data[keep]
Ah, got it - thanks! > PS: if you are loading any sizable data, the one thing you don't want to do > is to use read.table() ;) Yes ;) Romain and I (mostly Romain) are working on some faster alternatives at https://github.com/romainfrancois/fastread. One surprising finding so far (to me at least), is that when loading a file full of doubles, you pretty quickly get to the point where strtod is the bottleneck. Hadley -- Chief Scientist, RStudio http://had.co.nz/ ______________________________________________ R-devel@r-project.org mailing list https://stat.ethz.ch/mailman/listinfo/r-devel
