Rdo_which {Rdpack} | R Documentation |
Find elements of Rd objects for which a condition is true.
Rdo_which(rdo, fun) Rdo_which_tag_eq(rdo, tag) Rdo_which_tag_in(rdo, tags)
rdo |
an Rd object. |
fun |
a function to evaluate with each element of |
tag |
a character string. |
tags |
a character vector. |
These functions return the indices of the (top level) elements of
rdo
which satisfy a condition.
Rdo_which
finds elements of rdo
for which
the function fun
gives TRUE.
Rdo_which_tag_eq
finds elements with a specific Rd_tag
.
Rdo_which_tag_in
finds elements whose Rd_tag
's are among
the ones specified by tags
.
a vector of positive integers
Georgi N. Boshnakov
Rdo_locate
which searches recursively the Rd object.
## get the help page for topoc seq() rdo_seq <- tools::Rd_db("base")[["seq.Rd"]] ## find location of aliases in the topic ( ind <- Rdo_which_tag_eq(rdo_seq, "\alias") ) ## extract the first alias rdo_seq[[ ind[1] ]] ## Not run: ## extract all aliases rdo_seq[ind] ## End(Not run) ## db_bibtex <- tools::Rd_db("bibtex") ## names(db_bibtex) ## ## Rdo object for read.bib() ## rdo_read.bib <- db_bibtex[["read.bib.Rd"]] ## Rdo_tags(rdo_read.bib) ## ## ## which elements of read.bib are aliases? ## Rdo_which_tag_eq(rdo_read.bib, "\alias") ## rdo_read.bib[[3]] ## ## ## which elements of read.bib contain R code? ## Rdo_which(rdo_read.bib, function(x) any(Rdo_tags(x) == "RCODE") ) ## rdo_read.bib[[5]] ## ## which contain prose? ## Rdo_which(rdo_read.bib, function(x) any(Rdo_tags(x) == "TEXT") )