This post is a copy and paste of an r-blogger article.
However, it is so useful that I keep it here to remember about the process to save and restore all R packages when updating to a newer version of R.
- Before you upgrade, build a temp file with all of your old packages.
tmp <- installed.packages() installedpkgs <- as.vector(tmp[is.na(tmp[,"Priority"]), 1]) save(installedpkgs, file="installed_old.rda")
Install the new version of R and let it do it’s thing.
Once you’ve got the new version up and running, reload the saved packages and re-install them from CRAN.
tmp <- installed.packages() installedpkgs.new <- as.vector(tmp[is.na(tmp[,"Priority"]), 1]) missing <- setdiff(installedpkgs, installedpkgs.new) install.packages(missing) update.packages()