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tools (version 3.5.2)

Rdutils: Rd Utilities

Description

Utilities for computing on the information in Rd objects.

Usage

Rd_db(package, dir, lib.loc = NULL)

Arguments

package

a character string naming an installed package.

dir

a character string specifying the path to a package's root source directory. This should contain the subdirectory man with R documentation sources (in Rd format). Only used if package is not given.

lib.loc

a character vector of directory names of R libraries, or NULL. The default value of NULL corresponds to all libraries currently known. The specified library trees are used to search for package.

Details

Rd_db builds a simple database of all Rd objects in a package, as a list of the results of running parse_Rd on the Rd source files in the package and processing platform conditionals.

See Also

parse_Rd

Examples

Run this code
# NOT RUN {
## Build the Rd db for the (installed) base package.
db <- Rd_db("base")

## Keyword metadata per Rd object.
keywords <- lapply(db, tools:::.Rd_get_metadata, "keyword")
## Tabulate the keyword entries.
kw_table <- sort(table(unlist(keywords)))
## The 5 most frequent ones:
rev(kw_table)[1 : 5]
## The "most informative" ones:
kw_table[kw_table == 1]

## Concept metadata per Rd file.
concepts <- lapply(db, tools:::.Rd_get_metadata, "concept")
## How many files already have \concept metadata?
sum(sapply(concepts, length) > 0)
## How many concept entries altogether?
length(unlist(concepts))
# }

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