Question

Could you suggest me a way for loading packages in R automatically? I mean, I want to start a session in R without needing to use library('package name') several times. Suppose I downloaded all packages I’ll want to use the next time I start R.

Answer 1

Put library(foo) in your .Rprofile file or set R_DEFAULT_PACKAGES: see ?Rprofile …

In particular (because ?Rprofile is long and potentially intimidating):

If you want a different set of packages than the default ones when you
start, insert a call to ‘options’ in the ‘.Rprofile’ or
‘Rprofile.site’ file. For example, ‘options(defaultPackages =
character())’ will attach no extra packages on startup (only the
‘base’ package) (or set ‘R_DEFAULT_PACKAGES=NULL’ as an environment
variable before running R). Using ‘options(defaultPackages = “”)’ or
‘R_DEFAULT_PACKAGES=””’ enforces the R system default.

Since you probably do want all of the default packages loaded, and then extra ones in addition (rather than, say, not loading some of the default packages), you can either put

library("mypackage1")
library("mypackage2")
[etc.]

or using options(defaultPackages=...):

options(defaultPackages=c(getOption("defaultPackages"),
       "mypackage1","mypackage2", ... [etc.]))

in your .Rprofile to append your desired packages to the standard defaults.

edit (copied from comment) re getting this to work in Rstudio:
http://rstudio.org/docs/using/workspaces suggests that Rstudio executes .Rprofile and then “Performs the other actions described in R Startup [ http://stat.ethz.ch/R-manual/R-patched/library/base/html/Startup.html ]” (which is the same as ?Rprofile). It is ambiguous whether it looks at Rprofile.site or not.

edit #2: according to comment below, it does work with a recent version of Rstudio.