[R] Saving plots as byte streams

[Prof Brian Ripley]

On Fri, 9 Jan 2009, Richard.Cotton at hsl.gov.uk wrote:

> Is it possible to save plots as byte streams?

You mean bitmap plots?  E.g. PDF plots are not even written 
sequentially.

> For example, if I want the
> bytes for a PNG plot, I could use
>
> #Write the plot to a PNG file
> png("test.png")
> plot(1:10)
> dev.off()
>
> #Read the bytes back in from the file
> plotbytes <- readBin("test.png", "raw", n=2000)
>
> Ideally, I'd like to avoid having to bother writing to the file in the
> first place, and simply store the bytes in a variable.  How do I do this?

The bitmap library interfaces which we use write to files, so there is 
no way to do this short of rewriting all the bitmap code.  If there 
had been, they would be writing to connections already.

> Regards,
> Richie.
>
> Mathematical Sciences Unit
> HSL

-- 
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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