devNew: Opens a new device
Description
Opens a new device.Usage
devNew(type=getOption("device"), ..., scale=1, aspectRatio=1, par=NULL, label=NULL)Arguments
type
A character string specifying the type of device to be
opened. This string should match the name of an existing device
function. ...
Additional arguments passed to the device function, e.g.
width and height. If not given, the are inferred
from devOptions scale
A numeric scalar factor specifying how much the
width and the height should be rescaled. aspectRatio
A numeric ratio specifying the aspect ratio
of the image. See below. par
An optional named list of graphical settings applied,
that is, passed to par, immediately after
opening the device. label
An optional character string specifying the label of the
opened device. Value
- Returns what the device
function returns.
Width and heights
The default width and height of the generated image is specific to
the type of device used. There is not straightforward programatical
way to infer these defaults; here we use devOptions(), which
in most cases returns the correct defaults.Aspect ratio
The aspect ratio of an image is the height relative to the width.
If argument height is not given (or NULL), it is
calculated as aspectRatio*width as long as they are given.
Likewise, if argument width is not given (or NULL), it is
calculated as width/aspectRatio as long as they are given.
If neither width nor height is given, then width
defaults to devOptions(type)$width.
If both width and height are given, then
aspectRatio is ignored.