[Haskell] Re: 2-D Plots, graphical representation of massive data

[Glynn Clements]

karczma wrote:

> Glynn Clements proposes to: 
> 
> > Zabiyaka, Yuliya
> who wants
> ...
> >> 2) display result of the analysis (pie charts, histograms, plots) 
> > 
> > If you don't need to interact with the display, the simplest solution
> > is to generate graphics files. Personally, I would use PostScript, as
> > I'm reasonably familiar with it and the Ghostscript interpreter is
> > freely available.
> 
> Well, more than often proposing another *language* to process raw data
> might be an overkill.

I wasn't proposing *processing* the data in PostScript.

> I wouldn't dare to suggest that somebody learns PostScript just for
> that.

Nor would I.

> At least it was what I understood from Yuliya
> request for a Matlab 'plugin'... She needs rather a high-level processor
> with all the visualisation goodies, than another language.

To go back to the post to which I was replying, giving a little more
context:

> I get all these information out of Haskell simulator. Therefore I would like
> to be able to do two things in Haskell:
> 1) analyze the data (mean, std dev etc) - that's the easy part and I more or
> less know how to do it in Haskell
> 2) display result of the analysis (pie charts, histograms, plots) 

>From this, I assumed that the intent was to actually do the
statistical processing in Haskell, and that the only outstanding
question was "how do I draw stuff?".

Well, there are lots of ways in which you could draw stuff from
Haskell.

One is to use an in-process graphics library (e.g. GLUT/OpenGL,
wxHaskell, GTK+HS). However, if your Haskell environment doesn't
already include these, it could be highly non-trivial to actually get
to the point where you can use them.

Another is to use the core I/O functions (e.g. writeFile) to generate
files for an external program.

Either approach requires that you learn (or already know) the details
of a graphics library or file format. If you don't already know one, I
don't feel that PostScript would necessarily be any more involved than
e.g. OpenGL or GDK. You don't really have to understand the *language*
as such; there's no reason why you can't treat it as simply data, i.e. 
just write lots of 'show x ++ " " ++ show y ++ " lineto\n"'.

-- 
Glynn Clements <glynn.clements at virgin.net>