| % File src/library/utils/man/demo.Rd |
| % Part of the R package, https://www.R-project.org |
| % Copyright 1995-2012 R Core Team |
| % Distributed under GPL 2 or later |
| |
| \name{demo} |
| \alias{demo} |
| \title{Demonstrations of R Functionality} |
| \description{ |
| \code{demo} is a user-friendly interface to running some demonstration |
| \R scripts. \code{demo()} gives the list of available topics. |
| } |
| \usage{ |
| demo(topic, package = NULL, lib.loc = NULL, |
| character.only = FALSE, verbose = getOption("verbose"), |
| type = c("console", "html"), echo = TRUE, |
| ask = getOption("demo.ask"), |
| encoding = getOption("encoding")) |
| } |
| \arguments{ |
| \item{topic}{the topic which should be demonstrated, given as a |
| \link{name} or literal character string, or a character string, |
| depending on whether \code{character.only} is \code{FALSE} (default) |
| or \code{TRUE}. If omitted, the list of available topics is |
| displayed.} |
| \item{package}{a character vector giving the packages to look into for |
| demos, or \code{NULL}. By default, all packages in the search path |
| are used.} |
| \item{lib.loc}{a character vector of directory names of \R libraries, |
| or \code{NULL}. The default value of \code{NULL} corresponds to all |
| libraries currently known. If the default is used, the loaded |
| packages are searched before the libraries.} |
| \item{character.only}{logical; if \code{TRUE}, use \code{topic} as |
| character string.} |
| \item{verbose}{a logical. If \code{TRUE}, additional diagnostics are |
| printed.} |
| \item{type}{character: whether to show output in the console or a |
| browser (using the dynamic help system). The latter is honored only |
| in interactive sessions and if the \code{\link[knitr]{knitr}} |
| package is installed. Several other arguments are silently ignored |
| in that case, including \code{lib.loc}.} |
| \item{echo}{a logical. If \code{TRUE}, show the \R input when sourcing.} |
| \item{ask}{a logical (or \code{"default"}) indicating if |
| \code{\link{devAskNewPage}(ask = TRUE)} should be called before |
| graphical output happens from the demo code. The value |
| \code{"default"} (the factory-fresh default) means to ask if |
| \code{echo == TRUE} and the graphics device appears to be |
| interactive. This parameter applies both to any currently opened |
| device and to any devices opened by the demo code. If this is |
| evaluated to \code{TRUE} and the session is \link{interactive}, the |
| user is asked to press RETURN to start.} |
| \item{encoding}{See \code{\link{source}}. If the package has a |
| declared encoding, that takes preference.} |
| } |
| \details{ |
| If no topics are given, \code{demo} lists the available demos. For |
| \code{type = "console"}, the corresponding information is returned in |
| an object of class \code{"packageIQR"}. |
| } |
| \seealso{ |
| \code{\link{source}} and \code{\link{devAskNewPage}} which |
| are called by \code{demo}. \code{\link{example}} to run code |
| in the Examples section of help pages. |
| } |
| |
| \examples{ |
| demo() # for attached packages |
| |
| ## All available demos: |
| demo(package = .packages(all.available = TRUE)) |
| |
| \donttest{ |
| ## Display a demo, pausing between pages |
| demo(lm.glm, package = "stats", ask = TRUE) |
| |
| ## Display it without pausing |
| demo(lm.glm, package = "stats", ask = FALSE) |
| } |
| |
| \dontrun{ |
| ch <- "scoping" |
| demo(ch, character = TRUE) |
| } |
| |
| ## Find the location of a demo |
| system.file("demo", "lm.glm.R", package = "stats") |
| } |
| \keyword{documentation} |
| \keyword{utilities} |