Searches for a working PNG device
Searches for a working PNG device.
On Unix, the png device requires that X11 is available, which it is not
when running batch scripts or running R remotely. In such cases, an
alternative is to use the bitmap() device, which generates an
EPS file and the uses Ghostscript to transform it to a PNG file.
Moreover, if identical looking bitmap and vector graphics (EPS) files
are wanted for the same figures, in practice, bitmap() has
to be used.
By default, this method tests a list of potential graphical devices and
returns the first that successfully creates an image file.
By default, it tries to create a PNG image file via the built-in
png() device.
## Static method (use this): ## System$findGraphicsDevice(devices=list(png), maxCount=100, sleepInterval=0.1, ## findGhostscript=TRUE, ...) ## Don't use the below: ## S3 method for class 'System' findGraphicsDevice(static, devices=list(png), maxCount=100, sleepInterval=0.1, findGhostscript=TRUE, ...)
devices |
|
maxCount |
The maximum number of subsequent tests for the
the existences of |
sleepInterval |
The time in seconds between above subsequent tests. |
findGhostscript |
If |
... |
Not used. |
Henrik Bengtsson
For supported graphical devices, see capabilities().
png,
bitmap() and dev2bitmap.
*findGhostscript().
For more information see System.
fcn <- System$findGraphicsDevice()
if (identical(fcn, png)) {
cat("PNG device found: png()")
} else if (identical(fcn, bitmap)) {
cat("PNG device found: bitmap()")
} else {
cat("PNG device not found.")
}Please choose more modern alternatives, such as Google Chrome or Mozilla Firefox.