apropos {utils} | R Documentation |
Find Objects by (Partial) Name
Description
apropos()
returns a character vector giving the names of
objects in the search list matching (as a regular expression)
what
.
find()
returns where objects of a given name can be found.
Usage
apropos(what, where = FALSE, ignore.case = TRUE,
dot_internals = FALSE, mode = "any")
find(what, mode = "any", numeric = FALSE, simple.words = TRUE)
Arguments
what |
a character string. For |
where , numeric |
logical indicating whether positions in the search list should also be returned. |
ignore.case |
logical indicating if the search should be
case-insensitive, |
dot_internals |
logical indicating if the search result should show
base internal objects, |
mode |
a character string; if not |
simple.words |
logical; if |
Details
If mode != "any"
only those objects which are of mode mode
are considered.
find
is a different user interface for a similar task to
apropos
. By default (simple.words == TRUE
),
only whole names are matched. Unlike apropos
, matching is
always case-sensitive.
Unlike the default behaviour of ls
, names which
begin with a ‘.’ are included, but base ‘internal’ objects
are included only when dot_internals
is true.
Value
For apropos
, a character vector sorted by name. For
where = TRUE
this has names giving the (numerical) positions on
the search path.
For find
, either a character vector of environment names or
(for numeric = TRUE
) a numerical vector of positions on the
search path with names the names of the corresponding environments.
Author(s)
Originally, Kurt Hornik and Martin Maechler (May 1997).
See Also
glob2rx
to convert wildcard patterns to regular expressions.
objects
for listing objects from one place,
help.search
for searching the help system,
search
for the search path.
Examples
require(stats)
## Not run: apropos("lm")
apropos("GLM") # several
apropos("GLM", ignore.case = FALSE) # not one
apropos("lq")
cor <- 1:pi
find("cor") #> ".GlobalEnv" "package:stats"
find("cor", numeric = TRUE) # numbers with these names
find("cor", numeric = TRUE, mode = "function") # only the second one
rm(cor)
## Not run: apropos(".", mode = "list") # includes many datasets
# extraction/replacement methods (need a DOUBLE backslash '\\')
apropos("\\[")
# everything % not diff-able
length(apropos("."))
# those starting with 'pr'
apropos("^pr")
# the 1-letter things
apropos("^.$")
# the 1-2-letter things
apropos("^..?$")
# the 2-to-4 letter things
apropos("^.{2,4}$")
# frequencies of 8-and-more letter things
table(nchar(apropos("^.{8,}$")))