From: "Jean-Pierre Rosen" <rosen.adalog@wanadoo.fr>
Subject: Re: Ada for numerics computation (i.e. forget Fortran ?)
Date: 1999/04/26
Date: 1999-04-26T10:10:08+00:00 [thread overview]
Message-ID: <7g1e20$t12$1@wanadoo.fr> (raw)
In-Reply-To: 7fvpl8$mpm@drn.newsguy.com
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
next prev parent reply other threads:[~1999-04-26 0:00 UTC|newest]
Thread overview: 19+ messages / expand[flat|nested] mbox.gz Atom feed top
1999-04-23 0:00 Ada for numerics computation (i.e. forget Fortran ?) Hans N. Beck
1999-04-23 0:00 ` Markus Kuhn
1999-04-24 0:00 ` bglbv
1999-04-25 0:00 ` Edwin Guenthner
1999-04-25 0:00 ` bill
1999-04-25 0:00 ` Edwin Guenthner
1999-04-26 0:00 ` Jean-Pierre Rosen [this message]
1999-04-26 0:00 ` Edwin Guenthner
1999-04-26 0:00 ` Markus Kuhn
1999-04-27 0:00 ` me
1999-04-27 0:00 ` Jean-Pierre Rosen
1999-04-28 0:00 ` Edwin Guenthner
1999-04-28 0:00 ` Jean-Pierre Rosen
1999-04-27 0:00 ` Matthew Heaney
1999-04-27 0:00 ` dennison
1999-04-25 0:00 ` Robert Dewar
1999-04-23 0:00 ` Gautier
1999-04-23 0:00 ` Gautier
1999-04-27 0:00 ` Joachim Schroeer
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