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From: Gerald Kasner <Gerald.Kasner@Physik.Uni-Magdeburg.de>
Subject: Re: Ada->C++ conversion stats?
Date: 2000/03/22
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Hyman Rosen wrote:
> 
> "Robert L. Klungle" <bklungle@gte.net> writes:
> > The C++ version execution time is 3 times slower than the original Ada.
> > Primarily due to the implementation of an Array (Matrix) class as a
> > Class of Vectors-of-Vectors.
> > This was done to keep the matrix type of referencing ([][]). There is no
> > C++ operator to overload of this kind.
> 
> In addition to the B&N book, you should also look at the Blitz++ library.
> It uses the expression template technique to convert concisely written
> matrix operations into the equivalent of hand-optimized loops. It's free.
> See <http://oonumerics.org/blitz/index.html>.

Rather than using blitz or something like that, I would prefer libblas,
which 
is highly tuned and available for various platforms. C bindings should
be available 
at netlib.org.
If the matrix operations are responsible for the slowness, the use of
blas would 
give incredible speedups, even in the Ada version.

-Gerald