zpackages
Listing of Packages
Description
.packages
returns information about package availability.
Usage
.packages(all.available = FALSE, lib.loc = NULL)
Arguments
all.available | logical; if |
lib.loc | a character vector describing the location of R library trees to search through, or |
Details
.packages()
returns the names of the currently attached packages invisibly whereas .packages(all.available = TRUE)
gives (visibly) all packages available in the library location path lib.loc
.
For a package to be regarded as being ‘available’ it must have valid metadata (and hence be an installed package). However, this will report a package as available if the metadata does not match the directory name: use find.package
to confirm that the metadata match or installed.packages
for a much slower but more comprehensive check of ‘available’ packages.
Value
A character vector of package base names, invisible unless all.available = TRUE
.
Note
.packages(all.available = TRUE)
is not a way to find out if a small number of packages are available for use: not only is it expensive when thousands of packages are installed, it is an incomplete test. See the help for find.package
for why require
should be used.
Author(s)
R core; Guido Masarotto for the all.available = TRUE
part of .packages
.
See Also
library
, .libPaths
, installed.packages
.
Examples
(.packages()) # maybe just "base" .packages(all.available = TRUE) # return all available as character vector require(splines) (.packages()) # "splines", too detach("package:splines")
Copyright (©) 1999–2012 R Foundation for Statistical Computing.
Licensed under the GNU General Public License.