List Available Packages at CRAN-like Repositories
available.packages returns a matrix of details corresponding to
packages currently available at one or more repositories. The
current list of packages is downloaded over the internet (or copied
from a local mirror).
available.packages(contriburl = contrib.url(repos, type), method, fields = NULL, type = getOption("pkgType"), filters = NULL, repos = getOption("repos"))
- URL(s) of the contrib sections of the repositories. Specify this argument only if your repository mirror is incomplete, e.g., because you burned only the contrib section on a CD.
download method, see
character string, indicate which type of packages: see
type = "both"this will use the source repository.
a character vector giving the fields to extract from
the PACKAGES file(s) in addition to the default ones, or
NULL(default). Unavailable fields result in
a character vector or list or
NULL(default). See Details.
- character vector, the base URL(s) of the repositories to use.
The list of packages is either copied from a local mirror (specified by a
file:// URI) or downloaded. If downloaded, the list is cached
for the R session in a per-repository file in
with a name like
By default, the return value includes only packages whose version and OS requirements are met by the running version of R, and only gives information on the latest versions of packages.
filters can be used to select which of the packages on the
repositories are reported. It is called with its default value
NULL) by functions such as
install.packages: this value
c("R_version", "OS_type", "subarch", "duplicates") if
that is unset or set to
The built-in filters are
- Exclude packages whose R version requirements are not met.
contriburl) with the latest version if that is in more than one repository.
Note that this does depend on the repository supplying license information.
"duplicates"filter, so cannot be used with
add = TRUE.
If all the filters are from this set, then they can be specified as a
character vector; otherwise
filters should be a list with
elements which are character strings, user-defined functions or
add = TRUE (see below).
User-defined filters are functions which take a single argument, a
matrix of the form returned by
return a matrix consisting of a subset of the rows of the argument.
The special filter
add = TRUE appends the other
elements of the filter list to the default filters.
A matrix with one row per package, row names the package names and
column names including
"Repository". Additional columns can be specified using the
fieldsargument.Where provided by the repository, fields
"NeedsCompilation"are reported for use by the filters and package management tools, including
The R Installation and Administration manual for how to set up a repository.