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"), ignore_repo_cache = FALSE, max_repo_cache_age, quiet = TRUE, ...)
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
a character vector giving the fields to extract from
the ‘PACKAGES’ file(s) in addition to the default ones, or
a character vector or list or
character vector, the base URL(s) of the repositories to use.
logical. If true, the repository cache is never used (see ‘Details’).
any cached values older than this in seconds will be ignored. See ‘Details’.
logical, passed to
allow additional arguments to be passed from callers (which might be
arguments to future versions of this function). Currently these are
all passed to
The list of packages is either copied from a local mirror (specified by a
file:// URI) or downloaded. If downloaded and
ignore_repo_cache is false (the default), the list is cached
for the R session in a per-repository file in
with a name like
The cached values are renewed when found to be too old, with the age
limit controlled via argument
This defaults to the current value of the environment variable
R_AVAILABLE_PACKAGES_CACHE_CONTROL_MAX_AGE, or if unset, to
3600 (one hour).
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.
Exclude packages whose OS requirement is incompatible with this version of R: that is exclude Windows-only packages on a Unix-alike platform and vice versa.
For binary packages, exclude those with compiled code that is not available for the current sub-architecture, e.g. exclude packages only compiled for 32-bit Windows on a 64-bit Windows R.
Only report the latest version where more
than one version is available, and only report the first-named
contriburl) with the latest version if that
is in more than one repository.
Include only packages for which installation can proceed solely based on packages which can be verified as Free or Open Source Software (FOSS, e.g., https://en.wikipedia.org/wiki/FOSS) employing the available license specifications. Thus both the package and any packages that it depends on to load need to be known to be FOSS.
Note that this does depend on the repository supplying license information.
Include only packages for which installation can proceed solely based on packages which are known not to restrict use.
Use CRAN versions in preference to versions
from other repositories (even if these have a higher version
number). This needs to be applied before the default
"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
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.
## Not run: ## Count package licenses db <- available.packages(filters = "duplicates") table(db[,"License"]) ## Use custom filter function to only keep recommended packages ## which do not require compilation available.packages(filters = list( add = TRUE, function (db) db[db[,"Priority"] %in% "recommended" & db[,"NeedsCompilation"] == "no", ] )) ## Restrict install.packages() (etc) to known-to-be-FOSS packages options(available_packages_filters = c("R_version", "OS_type", "subarch", "duplicates", "license/FOSS")) ## or options(available_packages_filters = list(add = TRUE, "license/FOSS")) ## Give priority to released versions on CRAN, rather than development ## versions on R-Forge etc. options(available_packages_filters = c("R_version", "OS_type", "subarch", "CRAN", "duplicates")) ## End(Not run)
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