Re: Fortran vs C++ vs. etc (has little to do with realtime anymore)

[pvanesch@vub.ac.be (Vanesch P.)]

Dr. Krishnan Chittur (chitturk@email.uah.edu) wrote:
: Joseph M. O'Leary (NOSPAMjmoleary@earthlink.net) wrote:

: : Jeffrey Templon <templon@studbolt.physast.uga.edu> wrote in article
: : > The fact remains (and will for some time) that many scientific
: : programmers
: : > are scientists FIRST and programmers SECOND.  
: ........
: : > So one of my reasons for Fortran still being around: you can write
: : > a reasonable program which runs reasonably efficiently just by more
: : > or less typing in an expression of a simple algorithm.  Fortran's "mental
: : > model" of the computer is very simple.

: Well said! ... I still have to find an environment that will allow
: me to develop a GUI as simply as I can write Fortran Code to 
: do calculations ... if there is one, please let me know.

I think this is an essential point.  FORTRAN is well-suited to do
calculations and hard-core scientific computation.  But more 
complex structures (a GUI is program-wise a lot more complicated
than a scientific calculation) are not dealt too well with in
fortran I think.  I've seen this in the high-energy community.
Both elements are present there: complex software systems and
hard-core scientific computing.  Well, I've seen quite a mess
in the FORTRAN implementation (rather ad hoc) of the complicated
datastructures that had to be manipulated.  It would have been
much better done (and the tendency now is - finally - to switch
to things like C++) in a language suited for the task.

On the other hand, I've also seen the opposite.  A collegue of mine
wrote a MONSTER program in C++ to do some straightforward matrix
manipulations.  The graphical user interface launches tens and tens
of windows in which one can manipulate parameters, look at graphs etc...
He worked for almost a year on the thing.  He is a computer scientist,
btw, I'm not.  I'm an engineer and physicist.
It takes about 10 minutes to even start up the thing, getting your
X-terminal cluttered with all those windows.
I've done the same thing in F77, but with an ASCII steering file,
in about a month... and guess what ?  my program tackles systems 
he can't even dream of handling in just a few hours (his can't do it,
it just runs out of 1 GB swap space !!) I get a nice ASCII file
with my results. For smaller systems, my program is about 20 times
faster, with less memory, than his, on the same system.

I think every language has its uses.  FORTRAN is old and 
very elementary on the conceptual level.  For most modern
computing applications (graphics, process steering, multi-user
things etc) it is simply too elementary.
But for applications where these elementary concepts are
sufficient (such as scientific computing - which is usually
advanced on the scientific level and very simple on the 
computational level) it allows indeed to write a reasonably simple
program that behaves resonably well by someone who has some
reasonable knowledge of computers but is not a computer scientist, 
without involving a lot of abstract computer-think.

But if the project is too ambitious, and the abstract computer
think is really needed, well... I don't think it is a good idea
to do it in FORTRAN.


cheers,
Patrick.