[R] graphics backgrounds from gray to white in png()

[ripley@stats.ox.ac.uk]

Why are you using lattice for a single plot?

If you use lattice, you should be using trellis.device(), or at least
setting the lattice parameters *after* you open the device.  You set the 
parameters for a screen device (or whatever you had open before).

On Mon, 10 Mar 2003, Scot W McNary wrote:

> 
> 
> Hi,
> 
> I'm trying to make a png file of a histogram.  I would like a white
> background in the final product but end up producing a gray one, despite
> setting what I think are the correct parameters.  Suggestions for how to
> properly set a white background would be welcome.
> 
> Thanks in advance,
> 
> Scot
> 
> 
> # for non-lattice
> > par("bg"="white")
> > par("bg")
> [1] "white"
> 
> # for lattice
> background<-trellis.par.get("background")
> background$col<-"white"
> trellis.par.set("background",background)
> 
> > trellis.par.get("background")
> $col
> [1] "white"
> 
> # produces gray background in png, but white when plotted in active device
> > png(filename = "c:/windows/temp/test.png", width=480, height=640,
> + pointsize = 10, bg="white")
> > histogram(rnorm(500))
> > dev.off()
> windows
>       2

-- 
Brian D. Ripley,                  ripley at stats.ox.ac.uk
Professor of Applied Statistics,  http://www.stats.ox.ac.uk/~ripley/
University of Oxford,             Tel:  +44 1865 272861 (self)
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