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From: "Ian St. John" <istjohn@high-sense.com>
Subject: Re: Fortran or Ada?
Date: 1998/10/05
Date: 1998-10-05T00:00:00+00:00	[thread overview]
Message-ID: <3618dc33.0@news.passport.ca> (raw)
In-Reply-To: 6v9s4t$egn$1@ys.ifremer.fr


Michel OLAGNON wrote in message <6v9s4t$egn$1@ys.ifremer.fr>...
>In article <3617AA49.340A5899@icon.fi>, Niklas Holsti <nholsti@icon.fi>
writes:
<snip>
>>
>At the time of writing the software, it might not have been wrong.
>But later on, the launch procedure was changed for Ariane 4, and
>the computation no longer needed. IMHO, not removing unnecessary
>computations that may have side effects IS a "software error".
>
>The designers failed, IMHO, to note that even if hardware might
>be more likely to be wrong than software at time T0, over the whole
>expected service life of the system, it was software that had the highest
>probability to end up wrong.
>


IMHO, well tested software doesn't fail. Hardware does. At least, in the
sense of random errors. Software can have systematic errors, or design
limitations. Random errors and unexpected data indicate hardware problems.

The problem in the Arianne 5 case, were that there was no proper review of
whether the software testing was *valid* for arianne 5. This was a
*management* issue, not a technology issue. If the Arianne 4 had reported
such values ( causing overflow ) it *would* have been a hardware error. This
was taken into the design, and is correct as such.

The software was *correct* for the mission it was designed for ( Arianne
4 ). You cannot expect software re-use without evaluation of the
interface/inputs.

Nor can you design software with the viewpoint that it *might* be used in
the first warp drive spaceship. KISS, and stick to reality.






  reply	other threads:[~1998-10-05  0:00 UTC|newest]

Thread overview: 96+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
     [not found] <36068E73.F0398C54@meca.polymtl.ca>
1998-09-22  0:00 ` Fortran or Ada? Gisle S{lensminde
1998-09-22  0:00   ` Jeff Templon
1998-09-22  0:00     ` Rakesh Malhotra
1998-09-22  0:00     ` dewarr
1998-09-23  0:00       ` Jeff Templon
1998-09-23  0:00         ` Corey Minyard
1998-09-24  0:00           ` Craig Burley
1998-09-25  0:00             ` dewarr
1998-09-25  0:00               ` Jonathan Guthrie
1998-09-26  0:00               ` Craig Burley
1998-09-26  0:00                 ` dewarr
1998-09-26  0:00                   ` Craig Burley
1998-09-26  0:00                   ` Robert B. Love 
1998-09-24  0:00           ` Joel Seidman
1998-09-24  0:00         ` Marc A. Criley
1998-09-24  0:00           ` dewarr
1998-09-24  0:00             ` Robert I. Eachus
1998-09-24  0:00               ` William Clodius
1998-09-25  0:00                 ` dewarr
1998-09-25  0:00               ` dewarr
1998-09-25  0:00                 ` Robert I. Eachus
1998-09-25  0:00                   ` dewarr
1998-09-25  0:00             ` jbs
1998-09-26  0:00               ` dewarr
1998-09-28  0:00                 ` jbs
1998-09-29  0:00                   ` William B. Clodius
1998-09-30  0:00                     ` jbs
1998-09-30  0:00                       ` William Clodius
1998-09-30  0:00                       ` dewarr
1998-09-30  0:00                         ` jbs
1998-09-30  0:00                           ` William Clodius
1998-10-03  0:00                       ` Niklas Holsti
1998-10-03  0:00                         ` Toon Moene
1998-10-03  0:00                           ` Niklas Holsti
1998-10-03  0:00                             ` Toon Moene
1998-10-04  0:00                               ` Niklas Holsti
1998-10-05  0:00                                 ` Michel OLAGNON
1998-10-05  0:00                                   ` Ian St. John [this message]
1998-10-05  0:00                                     ` Richard D Riehle
1998-10-05  0:00                                       ` dewarr
1998-10-05  0:00                                     ` dewarr
1998-10-05  0:00                                       ` Ian St. John
1998-10-06  0:00                                         ` dewarr
1998-10-06  0:00                                           ` James Giles
1998-10-06  0:00                                             ` Mark A Biggar
1998-10-06  0:00                                               ` James Giles
1998-10-07  0:00                                                 ` dewarr
1998-10-07  0:00                                             ` dewarr
1998-10-06  0:00                                           ` Toon Moene
1998-10-06  0:00                                             ` Jonathan Guthrie
1998-10-06  0:00                                           ` Ian St. John
1998-10-08  0:00                                             ` Offtopic Airport Diversion (Was: Fortran or Ada?) Harold Stevens ** PLEASE SEE SIG **
1998-10-08  0:00                                               ` Ian St. John
1998-10-08  0:00                                             ` Fortran or Ada? Gary L. Scott
1998-10-06  0:00                                     ` Michel OLAGNON
1998-10-07  0:00                                       ` Ian St. John
1998-09-29  0:00                   ` Dean F. Sutherland
1998-09-29  0:00                   ` Dean F. Sutherland
1998-09-29  0:00                   ` Dean F. Sutherland
1998-09-29  0:00                   ` Gautier.DeMontmollin
1998-10-02  0:00                   ` Geoff Bull
1998-10-02  0:00                   ` Robert I. Eachus
1998-10-02  0:00                     ` jbs
1998-10-02  0:00                       ` William Clodius
1998-10-03  0:00                         ` jbs
1998-10-03  0:00                           ` Larry Elmore
1998-10-06  0:00                           ` Robert I. Eachus
1998-10-06  0:00                             ` Pat Rogers
1998-09-24  0:00           ` Jeff Templon
1998-09-25  0:00             ` dewarr
1998-09-25  0:00             ` Dale Stanbrough
1998-09-30  0:00               ` Daniel Barker
1998-09-30  0:00                 ` Lawrence Kirby
1998-10-01  0:00                   ` Aaron Crane
1998-10-02  0:00                 ` Fortran or Ada or gobbledygook? Wes Groleau
1998-10-05  0:00                 ` Fortran or Ada? Terry Devine
     [not found]           ` <6udre0$ha1$1@nnrp1.dejane <6utg60$h6l$1@nnrp1.dejanews.com>
1998-10-01  0:00             ` robin_v
1998-09-22  0:00     ` Larry Kilgallen
1998-09-22  0:00     ` Corey Minyard
1998-09-23  0:00     ` Frank Ecke
1998-09-23  0:00   ` bglbv
1998-09-23  0:00     ` Robert I. Eachus
1998-09-24  0:00       ` Richard D Riehle
1998-09-23  0:00 Marin David Condic, 561.796.8997, M/S 731-96
1998-09-23  0:00 ` Gisle S{lensminde
1998-09-24  0:00   ` John McCabe
1998-09-24  0:00     ` Dean F. Sutherland
1998-09-24  0:00     ` Gisle S{lensminde
1998-09-24  0:00 ` Samuel T. Harris
  -- strict thread matches above, loose matches on Subject: below --
1998-09-23  0:00 Marin David Condic, 561.796.8997, M/S 731-96
1998-09-24  0:00 Walt Brainerd
1998-09-25  0:00 ` Robert I. Eachus
1998-09-25  0:00 ` dewarr
1998-10-05  0:00 Robert I. Eachus
1998-10-05  0:00 Condic, Marin D.
1998-10-05  0:00 robin
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