[R] automatically calling dev.off()

[axionator]

Yes, it's a different model, but maybe my main problem is that Rserve does
not handle addTaskCallback as in the console (and thus no dev.off() is
called).

On Tue, Sep 1, 2015 at 5:00 PM, Duncan Murdoch <murdoch.duncan at gmail.com>
wrote:

> On 01/09/2015 10:13 AM, axionator wrote:
> > Yes, the user could add something. Here, In about 90% of the time, he
> > won't. So it would be nice to have a dev.off() as default (and some
> > extra handling if more plot commands will follow).
>
> That's a different mental model of how graphics should work, and it's
> not compatible with standard R graphics.  However, it would be pretty
> easy to get this to work with a grid graphics based systems (e.g.
> ggplot2, lattice) since they don't draw anything until you print the
> object:  you'd just need to override the print method.
>
> Duncan Murdoch
>
>
> >
> > On Tue, Sep 1, 2015 at 4:04 PM, Duncan Murdoch <murdoch.duncan at gmail.com
> > <mailto:murdoch.duncan at gmail.com>> wrote:
> >
> >     On 01/09/2015 7:34 AM, axionator wrote:
> >     > Hi,
> >     > is there a way to automatically call dev.off()?
> >     > I use options(device="myfunc") to automatically open a device to
> print to.
> >     > Afterwards, I would like to close it (so that the file is actually
> written).
> >     > I tried to do it via addTaskCallback, but unfortunately, I have to
> use
> >     > Rserve and (for any reason), the callback does not work (in the
> default R
> >     > console on win7 it works, however).
> >     >
> >     > So, the following runs in the R console (but not via Rserve):
> >     >
> >     > mypng <- function(filename = "test.png", ...)
> >     > {
> >     >     times <- function(total = 2, str = "Task") {
> >     >         ctr <- 0
> >     >         function(expr, value, ok, visible) {
> >     >             ctr <<- ctr + 1
> >     >             keep.me <http://keep.me> <- (ctr < total)
> >     >             if (ctr == total) {
> >     >                 cat("ENDPRINT")
> >     >                 dev.off()
> >     >             }
> >     >             keep.me <http://keep.me>
> >     >         }
> >     >     }
> >     >     png(filename, ...)
> >     >     n <- addTaskCallback(times(1))
> >     > }
> >     > options(device="mypng")
> >     > plot(rnorm(333))
> >     >
> >
> >     It wouldn't make sense to call dev.off() after the plot() command,
> >     because the user might be planning to add something to it.  You need
> to
> >     tell R that you are done, and that's what dev.off() is for.
> >
> >     You can call it automatically in a function by using
> >
> >     on.exit(dev.off())
> >
> >     and it should happen automatically at the end of an R session, but it
> >     *shouldn't* happen after every plotting call.
> >
> >     Duncan Murdoch
> >
> >
>
>

	[[alternative HTML version deleted]]