I am not seeing any good justification in your description for converting to matrix if you are planning to convert it back to data frame. Memory is going to be inefficiently-used if you do this. --------------------------------------------------------------------------- Jeff Newmiller The ..... ..... Go Live... DCN:<jdnew...@dcn.davis.ca.us> Basics: ##.#. ##.#. Live Go... Live: OO#.. Dead: OO#.. Playing Research Engineer (Solar/Batteries O.O#. #.O#. with /Software/Embedded Controllers) .OO#. .OO#. rocks...1k --------------------------------------------------------------------------- Sent from my phone. Please excuse my brevity.
David Romano <drom...@stanford.edu> wrote: >Hi everyone, > >I have large data frame, say df1, with 165K columns, and all but the >first >four columns of df1 are numeric. I transformed the numeric data and >obtained a matrix, call it data.m, with 165K - 4 columns, and then >tried to >create a second data frame by replacing the numeric columns of df1 by >data.m. I did this in two ways, and both ways instantly used up all >the >available memory, so I was wondering whether there was a better way to >do >this. > >Here's what I tried: > >df2 <- df1 >df2[ ,5:length(df1)] <- data.m > >and > >df2 <- cbind( df1[1:4], data.m) > >Thanks, >David > > [[alternative HTML version deleted]] > >______________________________________________ >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.