R: Download Packages from CRAN

update.packages {base}

R Documentation

Download Packages from CRAN

Description

These functions can be used to automatically compare the version numbers of installed packages with the newest available version on CRAN and update outdated packages on the fly.

Usage

update.packages(lib.loc = .lib.loc, CRAN = options("CRAN"),
                contriburl = contrib.url(CRAN),
                method = "auto", instlib = NULL,
                ask=TRUE, available=NULL)

installed.packages(lib.loc = .lib.loc)
CRAN.packages(CRAN = options("CRAN"), method = "auto",
              contriburl = contrib.url(CRAN))
old.packages(lib.loc = .lib.loc, CRAN = getOption("CRAN"),
             contriburl = contrib.url(CRAN),
             method = "auto", available = NULL)

download.packages(pkgs, destdir, available = NULL,
                  CRAN = options("CRAN"), method = "auto",
                  contriburl = contrib.url(CRAN))
install.packages(pkgs, lib, available = NULL,
                  CRAN = options("CRAN"), method = "auto",
                  contriburl = contrib.url(CRAN))

Arguments

`lib.loc`	A character vector describing the location of R library trees to search through (and update packages therein).
`CRAN`	The base URL of the CRAN mirror to use, i.e., the URL of a CRAN root such as `"http://www.r-project.org"` (the default) or its Statlib mirror, `"http://lib.stat.cmu.edu/R/CRAN"`.
`contriburl`	URL of the contrib section of CRAN. Use this argument only if your CRAN mirror is incomplete, e.g., because you burned only the contrib section on a CD. Overrides argument `CRAN`.
`method`	Download method, see `download.file`.
`pkgs`	A character vector of the short names of packages whose current versions should be downloaded from `CRAN`.
`destdir`	Directory where downloaded packages are stored.
`available`	List of packages available at CRAN as returned by `CRAN.packages`.
`lib,instlib`	A character string giving the library directory where to install the packages.
`ask`	If `TRUE`, ask before packages are actually downloaded and installed.

Details

installed.packages scans the `DESCRIPTION' files of each package found along lib.loc and returns a list of package names, library paths and version numbers. CRAN.packages returns a similar list, but corresponding to packages currently available in the contrib section of CRAN, the comprehensive R archive network. The current list of packages is downloaded over the internet (or copied from a local CRAN mirror). Both functions use parse.dcf for parsing the description files. old.packages compares the two lists and reports installed packages that have newer versions on CRAN.

download.packages takes a list of package names and a destination directory, downloads the newest versions of the package sources and saves the in destdir. If the list of available packages is not given as argument, it is also directly obtained from CRAN. If CRAN is local, i.e., the URL starts with "file:", then the packages are not downloaded but used directly.

The main function of the bundle is update.packages. First a list of all packages found in lib.loc is created and compared with the packages available on CRAN. Outdated packages are reported and for each outdated package the user can specify if it should be automatically updated. If so, the pre-compiled packages are downloaded from CRAN and installed in the respective library path (or instlib if specified).

install.packages can be used to install new packages, it takes a vector of package names and a destination directory, downloads the packages from CRAN and installs them. If the destination directory is omitted it defaults to the first directory in .lib.loc, with a warning. Argument pkgs can also be a character vector of file names of zip files if CRAN=NULL. The zip files are then unpacked directly.

Note