Plot optimization [Was: Re: [R] Plotting Speed: R vs Octave]

[Matej Cepl]

ripley at stats.ox.ac.uk wrote:
> > I will have to study your code, but it seems to me, that such
> > problem can occur quite often, so that optimization-out of
> > this ... well, I believe, bug ... could help a lot.
> 
> Plotting the points you asked for is not a bug: please read the
> FAQ about BUGS.

I know what bugs are (undocumented features :-), and that is the
reason why I have not filed it as bugreport, but to this list in
so hesitating way as I did.

> It is not often that users are careless enough to plot
> duplicated points many times.

Well, what I tried to say is that I do not think, that this
problem affects only careless users. I believe that pairs is best
exactly on very unprocessed raw data in multiple variables.
However, it may be fair to say, that pairs should be used only
for intial observations (with X11 driver, where I have no
problems with the size and complexity) and it should not be
published in the paper.

> The issue would apply to all drivers, not just postscript().

Actually, not exactly, because in bitmap-based drivers (X11, png,
jpeg) there is optimization done in hard way by the nature of the
bitmap pictures -- previous point just vanishes.

Have a nice day,

	Matej

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