options(...)
getOption(x, default = NULL)
.Optionsname = value.
However, only the ones below are used in base R.Options can also be passed by giving a single unnamed argument which is a named list.
getOption, the current value set for option x, or
NULL if the option is unset.For options(), a list of all set options sorted by name. For
options(name), a list of length one containing the set value,
or NULL if it is unset. For uses setting one or more options,
a list with the previous values of the options changed (returned
invisibly).
add.smooth:TRUE. Could also be set to an integer for specifying how
many (simulated) smooths should be added. This is currently only
used by plot.lm.browserNLdisabled:"n" in the browser.checkPackageLicense:library asks a user to accept any non-standard
license at first use.
check.bounds:FALSE. If
true, a warning is produced whenever a
vector (atomic or list) is extended, by something
like x <- 1:3; x[5] <- 6.CBoundsCheck:.C and .Fortran make copies to check for
array over-runs on the atomic vector arguments. Initially set from value of the environment variable
R_C_BOUNDS_CHECK (set to yes to enable).continue:defaultPackages:c("datasets", "utils", "grDevices", "graphics", "stats",
"methods"). (Set R_DEFAULT_PACKAGES to NULL or
a comma-separated list of package names.) It will not work to set
this in a ‘.Rprofile’ file, as its value is consulted before
that file is read.deparse.cutoff:deparsed.
Default 60.
deparse.max.lines:traceback, browser,
and upon entry to a function whose debugging flag is set.
Initially unset, and only used if set to a positive integer.digits:print.default about values greater than 15.digits.secs:strftime.download.file.extra:download.file.download.file.method:download.file. Currently download methods
"internal", "wininet" (Windows only),
"libcurl", "wget" and "curl" are available.
If not set, method = "auto"
is chosen: see download.file.echo:FALSE, but otherwise
it starts the session as TRUE.encoding:"native.enc". See connections.error:stop as well as by signals and internally detected
errors. If the option is a function, a call to that function,
with no arguments, is generated as the expression. The default
value is NULL: see stop for the behaviour in
that case. The functions dump.frames and
recover provide alternatives that allow post-mortem
debugging. Note that these need to specified as
e.g.\ifelse{latex}{\out{~}}{ } options(error = utils::recover) in startup
files such as ‘.Rprofile’.expressions:Memory. Note too that
you may cause a segfault from overflow of the C stack, and on OSes
where it is possible you may want to increase that. Once the
limit is reached an error is thrown. The current number under
evaluation can be found by calling Cstack_info.keep.source:TRUE, the source code for
functions (newly defined or loaded) is stored internally
allowing comments to be kept in the right places. Retrieve the
source by printing or using deparse(fn, control =
"useSource"). The default is interactive(), i.e., TRUE for
interactive use.keep.source.pkgs:keep.source, used only
when packages are installed. Defaults to FALSE unless the
environment variable R_KEEP_PKG_SOURCE is set to yes.max.print:99999.
print or show methods can make use of
this option, to limit the amount of information that is printed,
to something in the order of (and typically slightly less than)
max.print entries.OutDec:format and as.character but not when
deparsing nor by sprintf nor formatC
(which are sometimes used prior to printing.) Only single-byte characters were supported prior to R 3.2.0.
In R 3.2.1 and earlier, multi- (or zero-) character OutDec
were accepted, but always worked only partially.
pager:file.show.
unix
Defaults to ‘R_HOME/bin/pager’, which is a shell
script running the command-line specified by the environment
variable PAGER whose default is set at configuration,
usually to less.
windows
Defaults to "internal", which uses a pager similar to the
GUI console. Another possibility is "console" to use the
console itself.
Can be a character string or an R function, in which case it
needs to accept the arguments (files, header,
title, delete.file) corresponding to the first four arguments of
file.show.papersize:postscript; set by environment variable
R_PAPERSIZE when R is started: if that is unset or invalid
it defaults to
unix
a value derived from the locale category LC_PAPER, or
if that is unavailable to a default set when R was built.
windows
"a4", or "letter" in US and Canadian locales.
pdfviewer:open.exe, a utility
supplied with R.
printcmd:postscript
for printing; set by environment variable R_PRINTCMD when
R is started. This should be a command that expects either input
to be piped to ‘stdin’ or to be given a single filename
argument. Usually set to "lpr" on a Unix-alike.prompt:" ").rl_word_breaks:Used for the readline-based terminal
interface. Default value " \t\n\"\\'`><=%;,|&{()}"< code="">. This is the set of characters use to break the input line into
tokens for object- and file-name completion. Those who do not use
spaces around operators may prefer
" \t\n\"\\'`><=+-*%;,|&{()}"< code=""> save.defaults, save.image.defaults:-
see
save. scipen:- integer. A penalty to be applied
when deciding to print numeric values in fixed or exponential
notation. Positive values bias towards fixed and negative towards
scientific notation: fixed notation will be preferred unless it is
more than
scipen digits wider. showWarnCalls, showErrorCalls:- a logical.
Should warning and error messages show a summary of the call
stack? By default error calls are shown in non-interactive
sessions.
showNCalls:- integer. Controls how long the sequence
of calls must be (in bytes) before ellipses are used. Defaults to
40 and should be at least 30 and no more than 500.
show.error.locations:- Should source locations of
errors be printed? If set to
TRUE or "top", the
source location that is highest on the stack (the most recent
call) will be printed. "bottom" will print the location
of the earliest call found on the stack. Integer values can select other entries. The value 0
corresponds to "top" and positive values count down the
stack from there. The value -1 corresponds to
"bottom" and negative values count up from there.
show.error.messages:- a logical. Should error messages
be printed? Intended for use with
try or a
user-installed error handler. stringsAsFactors:- The default setting for arguments of
data.frame and read.table. texi2dvi:- used by functions
texi2dvi and texi2pdf in package tools.
unix
Set at startup from the environment variable R_TEXI2DVICMD,
which defaults first to the value of environment variable
TEXI2DVI, and then to a value set when R was installed (the
full path to a texi2dvi script if one was found). If
necessary, that environment variable can be set to "emulation".
timeout:- integer. The timeout for some Internet
operations, in seconds. Default 60 seconds. See
download.file and connections. topLevelEnvironment:- see
topenv and
sys.source. url.method:- character string: the default method for
url. Normally unset, which is equivalent to
"default", which is "internal" except on Windows. useFancyQuotes:- controls the use of
directional quotes in
sQuote, dQuote and in
rendering text help (see Rd2txt in package
tools). Can be TRUE, FALSE, "TeX" or
"UTF-8". verbose:- logical. Should R report extra information
on progress? Set to
TRUE by the command-line option
--verbose. warn:- sets the handling of warning messages. If
warn is negative all warnings are ignored. If warn
is zero (the default) warnings are stored until the top--level
function returns. If 10 or fewer warnings were signalled they
will be printed otherwise a message saying how many were
signalled. An object called last.warning is
created and can be printed through the function
warnings. If warn is one, warnings are
printed as they occur. If warn is two or larger all
warnings are turned into errors. warnPartialMatchArgs:- logical. If true, warns if
partial matching is used in argument matching.
warnPartialMatchAttr:- logical. If true, warns if
partial matching is used in extracting attributes via
attr. warnPartialMatchDollar:- logical. If true, warns if
partial matching is used for extraction by
$. warning.expression:- an R code expression to be called
if a warning is generated, replacing the standard message. If
non-null it is called irrespective of the value of option
warn. warning.length:- sets the truncation limit for error
and warning messages. A non-negative integer, with allowed values
100...8170, default 1000.
nwarnings:- the limit for the number of warnings kept
when
warn = 0, default 50. This will discard messages if
called whilst they are being collected. width:- controls the maximum number of columns on a
line used in printing vectors, matrices and arrays, and when
filling by
cat. Columns are normally the same as characters except in East Asian
languages. You may want to change this if you re-size the window that R is
running in. Valid values are 10...10000 with default normally
80. (The limits on valid values are in file ‘Print.h’ and can be
changed by re-compiling R.) Some R consoles automatically change
the value when they are resized. See the examples on Startup for one way to set this
automatically from the terminal width when R is started.
add.smooth |
TRUE |
check.bounds |
FALSE |
continue |
"+ " |
digits |
7 |
echo |
TRUE |
encoding |
"native.enc" |
error |
NULL |
expressions |
5000 |
keep.source |
interactive() |
keep.source.pkgs |
FALSE |
max.print |
99999 |
OutDec |
"." |
prompt |
"> " |
scipen |
0 |
show.error.messages |
TRUE |
timeout |
60 |
verbose |
FALSE |
warn |
0 |
warning.length |
1000 |
width |
80 |
bitmapType:(Unix-only) character. The default type for the
bitmap devices such as png. Defaults to
"cairo" on systems where that is available, or to
"quartz" on OS X where that is available. device:X11, windows or
quartz) for an interactive session, and pdf
in batch use or if a screen is not available. If set to the name
of a device, the device is looked for first from the global
environment (that is down the usual search path) and then in the
grDevices namespace. The default values in interactive and non-interactive sessions are
configurable via environment variables
R_INTERACTIVE_DEVICE and R_DEFAULT_DEVICE
respectively. The search logic for ‘the normal screen device’ is that
this is windows on Windows, and quartz if available
on OS X (running at the console, and compiled into the build).
Otherwise X11 is used if environment variable DISPLAY
is set.
device.ask.default:devAskNewPage("ask") when a device is opened.locatorBell:locator
and identify be confirmed by a bell? Default TRUE.
Honoured at least on X11 and windows devices.windowsTimeout:(Windows-only) integer vector of length 2
representing two times in milliseconds. These control the
double-buffering of windows devices when that is
enabled: the first is the delay after plotting finishes
(default 100) and the second is the update interval during
continuous plotting (default 500). The values at the time the
device is opened are used.
max.contour.segments:25000 if not set. A limit on the number of
segments in a single contour line in contour or
contourLines.contrasts:contrasts used in
model fitting such as with aov or lm.
A character vector of length two, the first giving the function to
be used with unordered factors and the second the function to be
used with ordered factors. By default the elements are named
c("unordered", "ordered"), but the names are unused.na.action:NA's) for certain situations.show.coef.Pvalues:printCoefmat.show.nls.convergence:nls
convergence messages be printed for successful fits?show.signif.stars:printCoefmat.ts.eps:ts) computations. Default 1e-05.ts.S.compat:log in plot.spec.BioC_mirror:setRepositories,
e.g.\ifelse{latex}{\out{~}}{ } the default "https://bioconductor.org"
or the European mirror
"https://bioconductor.statistik.tu-dortmund.de". Can be set
by chooseBioCmirror.browser:browseURL. This sets the default browser on UNIX or
a non-default browser on Windows. Alternatively, an R function
that is called with a URL as its argument. See
browseURL for further details.ccaddress:create.post (and hencebug.report and
help.request). Can be FALSE or "".citation.bibtex.max:bibentry) in a citation for
which the bibtex version is printed in addition to the text one.de.cellwidth:dataentry.
If this is unset (the default), 0, negative or NA, variable
cell widths are used.demo.ask:ask argument of
demo.editor:edit. Set from the
environment variable EDITOR on UNIX, or if unset
VISUAL or vi.example.ask:ask argument of
example.help.ports:startDynamicHelp.help.search.types:help.search and ??.help.try.all.packages:help.help_type:help, used also as the help type by ?.HTTPUserAgent:NULL, requests will be made without a
user agent header.
The default is R ( ) .install.lock:install.packages? Most useful
for binary installs on OS X and Windows, but can be used in a
startup file for source installs via
R CMD INSTALL. For binary installs, can also be
the character string "pkgloack".internet.info:"internal" and
"libcurl" methods.
Default is 2, for failure causes. Set to 1 or 0 to get more
detailed information (for the "internal" method 0 provides
more information than 1).
install.packages.check.source:install.packages (and indirectly
update.packages) on platforms which support binary
packages. Possible values "yes" and "no", with
unset being equivalent to "yes".install.packages.compile.from.source:install.packages(type = "both") (and indirectly
update.packages) on platforms which
support binary packages. Possible values are "never",
"interactive" (which means ask in interactive use and
"never" in batch use) and "always". The default is
taken from environment variable
R_COMPILE_AND_INSTALL_PACKAGES, with default
"interactive" if unset. However, install.packages
uses "never" unless a make program is found,
consulting the environment variable MAKE.mailer:create.post and hence bug.report and
help.request.menu.graphics:TRUE. Currently applies to
select.list, chooseCRANmirror,
setRepositories and to select from multiple (text)
help files in help.pkgType:install.packages.
windows
Possible values are "win.binary", "source" and
"both" (the default). Some OS X builds use
"mac.binary" and "mac.binary.mavericks".
unix
Possible values are "source" (the default except under a
CRAN OS X build), "mac.binary.",
"mac.binary.mavericks" and "both" (the default for
CRAN OS X builds). Windows uses
"win.binary". ("mac.binary.leopard" and
"mac.binary.universal" are no longer in use.)
Value "binary" is a synonym for the native binary type (if
there is one); "both" is used by
install.packages to choose between source and binary
installs.
repos:update.packages. Defaults to
c(CRAN="@CRAN@"), a value that causes some utilities to
prompt for a CRAN mirror. To avoid this do set the CRAN mirror,
by something like
local({r <- getOption("repos"); r["CRAN"] <- "http://my.local.cran";
options(repos = r)}). Note that you can add more repositories (Bioconductor,
R-Forge, Rforge.net ...)
using setRepositories.
SweaveHooks, SweaveSyntax:Sweave.
unzip:unzip:
the path of the external program unzip or "internal".
unix
Defaults to the value of R_UNZIPCMD, which is set in
‘etc/Renviron’ if an unzip command was found during
configuration.
windows
Defaults to "internal" when the internal unzip code is
used.
useHTTPS:chooseCRANmirror:
are secure mirrors preferred? If not set, TRUE is assumed.mc.cores:2 if it is unset.
dvipscmd:"dvips".options() with no arguments returns a list with the
current values of the options. Note that not all options listed below
are set initially. To access the value of a single option, one should
use, e.g., getOption("width") rather than
options("width") which is a list of length one.
op <- options(); utils::str(op) # op is a named list
getOption("width") == options()$width # the latter needs more memory
options(digits = 15)
pi
# set the editor, and save previous value
old.o <- options(editor = "nedit")
old.o
options(check.bounds = TRUE, warn = 1)
x <- NULL; x[4] <- "yes" # gives a warning
options(digits = 5)
print(1e5)
options(scipen = 3); print(1e5)
options(op) # reset (all) initial options
options("digits")
## Not run: ## set contrast handling to be like S
# options(contrasts = c("contr.helmert", "contr.poly"))
# ## End(Not run)
## Not run: ## on error, terminate the R session with error status 66
# options(error = quote(q("no", status = 66, runLast = FALSE)))
# stop("test it")
# ## End(Not run)
## Not run: ## Set error actions for debugging:
# ## enter browser on error, see ?recover:
# options(error = recover)
# ## allows to call debugger() afterwards, see ?debugger:
# options(error = dump.frames)
# ## A possible setting for non-interactive sessions
# options(error = quote({dump.frames(to.file = TRUE); q()}))
# ## End(Not run)
# Compare the two ways to get an option and use it
# acconting for the possibility it might not be set.
if(as.logical(getOption("performCleanp", TRUE)))
cat("do cleanup\n")
## Not run:
# # a clumsier way of expressing the above w/o the default.
# tmp <- getOption("performCleanup")
# if(is.null(tmp))
# tmp <- TRUE
# if(tmp)
# cat("do cleanup\n")
# ## End(Not run)
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