installed.packages Find Installed Packages

Description

Find (or retrieve) details of all packages installed in the specified libraries.

Usage

installed.packages(lib.loc = NULL, priority = NULL,
                   noCache = FALSE, fields = NULL,
                   subarch = .Platform$r_arch, ...)

Arguments

lib.loc	character vector describing the location of R library trees to search through, or NULL for all known trees (see .libPaths).
priority	character vector or NULL (default). If non-null, used to select packages; "high" is equivalent to c("base", "recommended"). To select all packages without an assigned priority use priority = "NA".
noCache	Do not use cached information, nor cache it.
fields	a character vector giving the fields to extract from each package's DESCRIPTION file in addition to the default ones, or NULL (default). Unavailable fields result in NA values.
subarch	character string or NULL. If non-null and non-empty, used to select packages which are installed for that sub-architecture.
...	allows unused arguments to be passed down from other functions.

Details

installed.packages scans the ‘DESCRIPTION’ files of each package found along lib.loc and returns a matrix of package names, library paths and version numbers.

The information found is cached (by library) for the R session and specified fields argument, and updated only if the top-level library directory has been altered, for example by installing or removing a package. If the cached information becomes confused, it can be avoided by specifying noCache = TRUE.

Value

A matrix with one row per package, row names the package names and column names (currently) "Package", "LibPath", "Version", "Priority", "Depends", "Imports", "LinkingTo", "Suggests", "Enhances", "OS_type", "License" and "Built" (the R version the package was built under). Additional columns can be specified using the fields argument.

Note

This needs to read several files per installed package, which will be slow on Windows and on some network-mounted file systems.

It will be slow when thousands of packages are installed, so do not use it to find out if a named package is installed (use find.package or system.file) nor to find out if a package is usable (call requireNamespace or require and check the return value) nor to find details of a small number of packages (use packageDescription).

See Also

update.packages, install.packages, INSTALL, REMOVE.

Examples

## confine search to .Library for speed
str(ip <- installed.packages(.Library, priority = "high"))
ip[, c(1,3:5)]
plic <- installed.packages(.Library, priority = "high", fields = "License")
## what licenses are there:
table( plic[, "License"] )