Opens a new device.
devNew(type=getOption("device"), ..., scale=1, aspectRatio=1, par=NULL, label=NULL)
Returns the device index of the opened device.
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
().
A numeric
scalar factor specifying how much the
width and the height should be rescaled.
A numeric
ratio specifying the aspect ratio
of the image. See below.
An optional named list
of graphical settings applied,
that is, passed to par
, immediately after
opening the device.
An optional character
string specifying the label of the
opened device.
The default width and height of the generated image is specific to
the type of device used. There is not straightforward programmatic
way to infer these defaults; here we use devOptions
(), which
in most cases returns the correct defaults.
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.
Henrik Bengtsson
devDone
() and devOff
().
For simplified generation of image files, see devEval
().