RE: About coordinated efforts on scientific software.

[JJ Gomez-Cadenas <gomez at ific dot uv dot es>]

Hi again,
I have been looking into Babel
http://www.llnl.gov/CASC/components/babel.html

And it looks as a promising way of generating common interfaces for all
major scientific dialects.

However, I have a number of doubts. Let's see:

1) How much is the overhead to be payed? Very often in numerical
calculations performance is an issue.

2) SIDL, the scientific interface design language in which BABEL is based
has its own arrays and complex numbers. So it does GSL. Does that mean a lot
of copying to and fro, if one wants to stick to Babel types? Or one could
define GSL types, this seems to be easy enough in SIDL.

3) Python internals are based on Numphy which also has its own arrays. Same
question.

4) Is it worth? It depends on how many languages one really needs to glue
together. For C++ only it would clearly be an overkill. Add python and it
starts to be interesting. This two, I am sure are heavily used. Babel also
supports Java and Fortran. That makes it quite interesting, there is a lot
of people out there using FORTRAN still.

I would like that some body else (Alan?, Brian?) takes a look to this Babel
business and bring the discussion on line. I am becoming convinced that it
is a fundamental issue to be answered in order to help GSL to become the
core library for scientific calculations.

Best, JJ

-----Mensaje original-----
De: gsl-discuss-owner@sources.redhat.com
[mailto:gsl-discuss-owner@sources.redhat.com]En nombre de Alan
Aspuru-Guzik
Enviado el: lunes, 21 de octubre de 2002 19:05
Para: gsl-discuss@sources.redhat.com
Asunto: About coordinated efforts on scientific software.



This e-mail is a reply to Cristoph Siopi's email.

Some points:

There is a relevant coordinated effort by the Department of Energy for
creating a common base for scientific software. I actually went to a
workshop for the ACTS Toolkit:
http://acts.nersc.gov/

Which is a collection of software that is released using the GPL licencse
for most cases, and that is well suited for some of the tasks that people
need.  For example, if one needs parallel Matrix and Vector operations, I
recommend to take a look at PetSc. It looks really good.

I have been using GSL, and doing my vector MPI distribution by hand, just
because I did not know that such tools were in such advanced state, and
that they were actually written in C, etc.

Another very, VERY interesting effort, similar to what the GNOME people
wanted to do using CORBA as a glue for their component architecture,
Bonobo, is the Common Components Architecture:
http://www.cca-forum.org/

During the same workshop, I attended a one day tutorial on it, and it
seems very promising. When it becomes more mature, it would be very
interesting for one of us (maybe me) to CCA-ize the GSL, in such a way
that it can be used in conjuction with the tools from ACTS, that are
already starting to be CCAized (like TAO, the Toolkit for Advanced
Optimization).

So there are some people that are indeed looking at the big picture. Maybe
what we need in the volunteer arena is leadership and organization like
the one that started umbrella projects, such as GNOME or KDE, that brought
a lot of people together.

Greetings,
Alan

--

Alan Aspuru-Guzik                    Dios mueve al jugador, y éste, la
pieza.
(510)642-5911 UC Berkeley           ¿Qué Dios detrás de Dios la trama
empieza
(925)422-8739 LLNL                de polvo y tiempo y sueño y
agonías? -Borges