Run R command from command line

Question

Is there a way to run an R command from the command line? Something like

$ R --run '1+1'
2

or even like

$ Rscript < '1+1'
2

Answer 1

The command line option -e does exactly that.

Rscript.exe -e "1+1"

[1] 2

It is clearly explained in the help which you get if you just run RScript without parameters:

Usage: /path/to/Rscript [--options] [-e expr [-e expr2 ...] | file] [args]

--options accepted are
  --help              Print usage and exit
  --version           Print version and exit
  --verbose           Print information on progress
  --default-packages=list
                      Where 'list' is a comma-separated set
                        of package names, or 'NULL'
or options to R, in addition to --slave --no-restore, such as
  --save              Do save workspace at the end of the session
  --no-environ        Don't read the site and user environment files
  --no-site-file      Don't read the site-wide Rprofile
  --no-init-file      Don't read the user R profile
  --restore           Do restore previously saved objects at startup
  --vanilla           Combine --no-save, --no-restore, --no-site-file
                        --no-init-file and --no-environ

'file' may contain spaces but not shell metacharacters
Expressions (one or more '-e <expr>') may be used *instead* of 'file'
See also  ?Rscript  from within R

Answer 2

You can do it with the R command:

$ R --slave -e '1+1'
[1] 2

From man R:

   --slave
          Make R run as quietly as possible

   -e EXPR
          Execute 'EXPR' and exit