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From: "Jean-Pierre Rosen" <rosen.adalog@wanadoo.fr>
Subject: Re: Ada for numerics computation (i.e. forget Fortran ?)
Date: 1999/04/26
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bill@ a �crit dans le message <7fvpl8$mpm@drn.newsguy.com>...
[lot of interesting stuff deleted]

Don't forget also the problem with arrays and dynamic allocation.
Since every object is dynamically allocated, a 100x100 array of
anything but simple types will require 10_000 dynamic allocations.
Since there are NO multi-dimensionnal arrays (only arrays of arrays),
even a 100x100 array of int will require 100 dynamic allocations.

Moreover, the "array of arrays" paradigm has a very unfortunate
consequence: if you clone an array of arrays, only the *first*
dimension gets cloned, i.e. you get a array which is partially cloned,
partially shared. Such a beast has neither a value nor a reference
semantics! And since arrays have no definitions of their own, it is
not possible to redefine a "clone", unless you package your array into
something else.

When I see benchmarks telling that Java is almost as fast as compiled
code, I really wonder if the benchmarks included things like matrix
operations... Does anyone have figures of Java efficiency in this area
?
---------------------------------------------------------
           J-P. Rosen (Rosen.Adalog@wanadoo.fr)
Visit Adalog's web site at http://perso.wanadoo.fr/adalog