Hi,

Sorry to not include a subject last time, or provide more info on yorick:

http://yorick.sourceforge.net/index.php official http://www.maumae.net/yorick/doc/index.php unofficial

It's basically an interpreter geared toward doing numerics, with C-like syntax (but Fortran array indexing) and very elegant multi-D array syntax. It's also quite fast, has a parallel MPI package, and is used at LLNL to steer some big numerical codes where the 'guts' are in C. Also has a graphics package called gist. It's a free, open-source, bare-bones matlab, written by David Munro of LLNL starting in I think the late 1980s.

At the risk of being glib, I find the current science tools in python (numpy, scipy, matplotlib) to be a good beta version of yorick :)

Anyway, my point was there are a lot of standard grid gymnastics, of which numpy's diff() and sum() are examples, which don't seem to be in numpy, like yorick's zcen (zone centering) and pcen (point centering). Rather than everyone write their own, perhaps they could be included? Unless they're in numpy and I can't find where.

Cheers Dave [Strozzi, not Munro]

At 11:19 AM +0200 5/14/09, Sebastian Walter wrote:

On Wed, May 13, 2009 at 10:18 PM, David J Strozzi strozzi2@llnl.gov wrote:

...

Hi,

[You may want to edit the numpy homepage numpy.scipy.org to tell people they must subscribe to post, and adding a link to http:// www. scipy.org/Mailing_Lists]

Many of you probably know of the interpreter yorick by Dave Munro. As a Livermoron, I use it all the time.

Never heard of it... what does it do? By the sound of it, yorick is an interpreted language like Python.

...

There are some built-in functions there, analogous to but above and beyond numpy's sum() and diff(), which are quite useful for common operations on gridded data. Of course one can write their own, but maybe they should be cleanly canonized?

For instance:

x = linspace(0,10,10) y = sin(x)

It is common, say when integrating y(x), to take "point-centered" data and want to zone-center it:

I = sum(zcen(y)*diff(x))

def zcen(x): return 0.5*(x[0:-1]+x[1:])

Besides zcen, yorick has builtins for "point centering", "un-zone centering," etc. Also, due to its slick syntax you can give these things as array "indexes":

x(zcen), y(dif), z(:,sum,:)

Just some thoughts, David Strozzi _______________________________________________ Numpy-discussion mailing list Numpy-discussion@scipy.org http:// mail.scipy.org/mailman/listinfo/numpy-discussion

---

Numpy-discussion mailing list Numpy-discussion@scipy.org http:// mail.scipy.org/mailman/listinfo/numpy-discussion