dflplot 0.01

[dsimcha]

== Quote from Philippe Sigaud (philippe.sigaud at gmail.com)'s article
> --0016e6d77e7b9e1ca7048b1bb56b
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> On Sun, Jul 11, 2010 at 13:52, Lars T. Kyllingstad
> <public at kyllingen.nospamnet> wrote:
> > On Sat, 10 Jul 2010 20:51:15 +0000, dsimcha wrote:
> >
> > > BTW, since my attachment didn't actually get attached, I've put up the
> > > latest screenshot, produced from my demo/testing function, at:
> > >
> > >
http://cis.jhu.edu/~dsimcha/dflplot.png<http://cis.jhu.edu/%7Edsimcha/dflplot.png>
> >
> >
> > Wow, I'd say that's looking pretty polished already. :)  I think it's
> > great that you've done this, it brings D another step closer to being a
> > versatile numerics language.  I'm looking forward to the day this becomes
> > available for *NIX too.
> >
> > -Lars
> >
> What's the last plot? Some kind of density plot, maybe a heat map?
> Philippe

Yes, that was just checked in yesterday.  in dflplot it's called a HeatScatter,
and it's a subclass of HeatMap.  It's also known as a 2-d histogram.  It's useful
if you want to visualize a joint distribution between two variables, but you have
a large sample size, so using a scatter plot would produce an overwhelming number
of points.

Each cell is either dark (high probability) or light(low probability).  The "hot"
and "cold" color are customizable.  In this case each sample is distributed
Normal(1, 1) on the y-axis and Normal(-2, 1) + x_i on the x-axis.