Re: The Ada Scalar, Vector, Matrix and Tensor arithmetic library?

["E. Robert Tisdale" <edwin@netwood.net>]

Pascal Obry wrote:

> David C. Hoos, Sr. <david.c.hoos.sr@ada95.com>
> a �crit dans l'article <82dk7t$5ka$1@birch.prod.itd.earthlink.net>...
> > I would say that an API should liberate its clients' programmers
> > to concentrate on their client application, by presenting a good
> > abstraction of the functionality provided by the library.
> >
> > If that makes the implementation more difficult, then so be it.
> > Even, performance, in my view should play a role secondary to
> > the presentation of a good abstraction, given that today the costs
> > of machine performance continue to plummet, while the cost of
> > software development, and the cost of correcting software errors
> > continue to escalate.
>
> Right, I completely agree. We really want to make any abstraction
> usable for a *human* and just let the compiler do its job.
>
> It cost less today to buy a new fastest machine than to juggle around
> with the code in the hope to gain some percent of performance.
> It takes a lot of time to tune the code
> and it is often a real nightmare to maintain this kind code.

I agree.  But compiler technology isn't as good as it should be yet --
especially for Ada compilers.  It is easy to write numerical codes
that are thousands of times slower than they need to be.
Library developers should decide how much tuning and maintenance
they need to do to make their implementation competitive
with other implementations.
Competition benefits application programmers
only if library developers all support a standard API
and can substitute one implementation for another at any time.

E. Robert Tisdale <edwin@netwood.net>