Utilities for computing on the information in Rd objects.
a character string naming an installed package.
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
a character vector of directory names of R libraries,
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.
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## 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))