Re: Numerical Computation and Ada95

[dvdeug@x8b4e53cd.dhcp.okstate.edu (David Starner)]

On Wed, 9 May 2001 22:13:31 +0300, N&J <nikogian@hotmail.com> wrote:
> I asked if Ada95 is better that Fortran90/95 and C++ for writing programs
> for numerical computation and the reply was that the Ada language
> specification requires extensive
> run-time checks which slows down the programs. 

There's always the question on whether you want fast programs or 
correct programs. (-: Most Ada compilers offer switches to turn off
run-time checks, so there should be practically no difference 
between the speed of Fortran, C++ and Ada. (In practice, Ada seems
to be slightly slower (10-20%) even with the checks turned off. This
will of course vary widely depending on your program and enviroment.)

> I have noticed that there are too few numerical
> programs in Ada95 for numerical computation is the above fact the real cause
> for this? 

Ada has various stigmas in the programming community and Fortran users
seem to be reluctant to ever give up Fortran. (I have a teacher who
still complains that changes between Fortran 66 and Fortran 77 broke
some code of his. He is also of the Fortran is the universal programming
language mindset.)

> Finally would you suggest someone to use Ada95 for numerical code?

(Donning abestos suit.) Probably not. Fortran and C++ have a variety
of optimized, tested numeric libraries, like Lapack and Blitz, that
are generally missing from Ada. (I'm sure someone will pop up with
some Ada binding to them, or one of the numeric libraries for Ada.
The first tends to be slower than just using the real thing, and if
you're using Lapack, why not just use Fortran? The latter are
neither optimized or heavily bug tested.) Ada does have the
advantage in having a free, highly ported compiler (GNAT), where as
Fortran 90/95 doesn't.

-- 
David Starner - dstarner98@aasaa.ofe.org
Pointless website: http://dvdeug.dhis.org
"I don't care if Bill personally has my name and reads my email and 
laughs at me. In fact, I'd be rather honored." - Joseph_Greg