R: Plot Output

renderPlot {shiny}

R Documentation

Plot Output

Description

Renders a reactive plot that is suitable for assigning to an output slot.

Usage

renderPlot(
  expr,
  width = "auto",
  height = "auto",
  res = 72,
  ...,
  alt = NA,
  env = parent.frame(),
  quoted = FALSE,
  execOnResize = FALSE,
  outputArgs = list()
)

Arguments

`expr`	An expression that generates a plot.
`width`, `height`	Height and width can be specified in three ways: `"auto"`, the default, uses the size specified by `plotOutput()` (i.e. the `offsetWidth`/'offsetHeight“ of the HTML element bound to this plot.) An integer, defining the width/height in pixels. A function that returns the width/height in pixels (or `"auto"`). The function is executed in a reactive context so that you can refer to reactive values and expression to make the width/height reactive. When rendering an inline plot, you must provide numeric values (in pixels) to both `width` and `height`.
`res`	Resolution of resulting plot, in pixels per inch. This value is passed to `plotPNG()`. Note that this affects the resolution of PNG rendering in R; it won't change the actual ppi of the browser.
`...`	Arguments to be passed through to `plotPNG()`. These can be used to set the width, height, background color, etc.
`alt`	Alternate text for the HTML `⁠<img>⁠` tag if it cannot be displayed or viewed (i.e., the user uses a screen reader). In addition to a character string, the value may be a reactive expression (or a function referencing reactive values) that returns a character string. If the value is `NA` (the default), then `ggplot2::get_alt_text()` is used to extract alt text from ggplot objects; for other plots, `NA` results in alt text of "Plot object". `NULL` or `""` is not recommended because those should be limited to decorative images.
`env`	The parent environment for the reactive expression. By default, this is the calling environment, the same as when defining an ordinary non-reactive expression. If `expr` is a quosure and `quoted` is `TRUE`, then `env` is ignored.
`quoted`	If it is `TRUE`, then the `quote()`ed value of `expr` will be used when `expr` is evaluated. If `expr` is a quosure and you would like to use its expression as a value for `expr`, then you must set `quoted` to `TRUE`.
`execOnResize`	If `FALSE` (the default), then when a plot is resized, Shiny will replay the plot drawing commands with `grDevices::replayPlot()` instead of re-executing `expr`. This can result in faster plot redrawing, but there may be rare cases where it is undesirable. If you encounter problems when resizing a plot, you can have Shiny re-execute the code on resize by setting this to `TRUE`.
`outputArgs`	A list of arguments to be passed through to the implicit call to `plotOutput()` when `renderPlot` is used in an interactive R Markdown document.

Details

The corresponding HTML output tag should be div or img and have the CSS class name shiny-plot-output.

Interactive plots

With ggplot2 graphics, the code in renderPlot should return a ggplot object; if instead the code prints the ggplot2 object with something like print(p), then the coordinates for interactive graphics will not be properly scaled to the data space.