[R] How to capture multiple graph pages to .png ?

[Deepayan Sarkar]

On Mon, Jan 5, 2009 at 4:57 PM, Mike Williamson <this.is.mvw at gmail.com> wrote:
> Greg, others,
>
>    Thanks for the info!  I suspect you are right, Greg.
>
>    The main issue, as Sundar Dorai-Raj (who posts here at times) told me in
> person and you say indirectly below, is that the "levelplot" function
> returns an object and not a graph.  I didn't really know what that *meant*,
> even though I'd read it, until he explained it to me.  In short, it means
> that if you want levelplot to plot as usual, you need to wrap it in a print
> statement (same as you're saying below).  I think this is hidden somewhere
> in the FAQ's, but it still isn't obvious and it'd be great if this were
> added directly in the ?levelplot help menu.

For the record, ?levelplot does say:

Value:

     An object of class '"trellis"'. The 'update' method can be used to
     update components of the object and the 'print' method (usually
     called by default) will plot it on an appropriate plotting device.

and ?Lattice explains this in more detail.

-Deepayan