On Thu, Jun 24, 2010 at 1:51 PM, Joshua Wiley <jwiley.ps...@gmail.com> wrote: > Hello Ralf, > > This is a little function that you may find helpful. If the package > is already installed, it just loads it, otherwise it updates the > existing packages and then installs the required package. As in > require(), 'x' does not need to be quoted. > > load.fun <- function(x) { > x <- as.character(substitute(x)) > if(isTRUE(x %in% .packages(all.available=TRUE))) { > eval(parse(text=paste("require(", x, ")", sep=""))) > } else { > update.packages() # recommended before installing so that > dependencies are the latest version > eval(parse(text=paste("install.packages('", x, "')", sep=""))) > } > }
I miscopied the last line; it should be.... ########### load.fun <- function(x) { x <- as.character(substitute(x)) if(isTRUE(x %in% .packages(all.available=TRUE))) { eval(parse(text=paste("require(", x, ")", sep=""))) } else { update.packages() # recommended before installing so that dependencies are the latest version eval(parse(text=paste("install.packages('", x, "')", sep=""))) eval(parse(text=paste("require(", x, ")", sep=""))) } } ########### > > HTH, > > Josh > > On Thu, Jun 24, 2010 at 12:25 PM, Ralf B <ralf.bie...@gmail.com> wrote: >> Hi fans, >> >> is it possible for a script to check if a library has been installed? >> I want to automatically install it if it is missing to avoid scripts >> to crash when running on a new machine... >> >> Ralf >> >> ______________________________________________ >> 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. >> > > > > -- > Joshua Wiley > Ph.D. Student > Health Psychology > University of California, Los Angeles > -- Joshua Wiley Ph.D. Student Health Psychology University of California, Los Angeles ______________________________________________ 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.